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| versions
list | update_date
timestamp[s] | authors_parsed
sequence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0704.3901 | Stefan Kr\"omer | Stefan Kr\"omer | Existence and symmetry of minimizers for nonconvex radially symmetric
variational problems | 22 pages, submitted to Calculus of Variations and Partial
Differential Equations | null | null | null | math.CA | null | Nonconvex functionals with spherical symmetry are studied. Existence of one
and radial symmetry of all global minimizers is shown with an approach based on
convex relaxation.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 09:12:59 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Krömer",
"Stefan",
""
]
] |
0704.3902 | Yuri Yakubovich | Alexander Gnedin, Yuri Yakubovich | On the number of collisions in $\Lambda$-coalescents | 18 pages | null | null | null | math.PR | null | We examine the total number of collisions $C_n$ in the $\Lambda$-coalescent
process which starts with $n$ particles. A linear growth and a stable limit law
for $C_n$ are shown under the assumption of a power-like behaviour of the
measure $\Lambda$ near 0 with exponent $0<\alpha<1$.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 09:16:35 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Gnedin",
"Alexander",
""
],
[
"Yakubovich",
"Yuri",
""
]
] |
0704.3903 | Koji Chinen | Koji Chinen | An abundance of invariant polynomials satisfying the Riemann hypothesis | 19 pages | null | null | null | math.NT | null | In 1999, Iwan Duursma defined the zeta function for a linear code as a
generating function of its Hamming weight enumerator. It can also be defined
for other homogeneous polynomials not corresponding to existing codes. If the
homogeneous polynomial is invariant under the MacWilliams transform, then its
zeta function satisfies a functional equation and we can formulate an analogue
of the Riemann hypothesis. As far as existing codes are concerned, the Riemann
hypothesis is believed to be closely related to the extremal property.
In this article, we show there are abundant polynomials invariant by the
MacWilliams transform which satisfy the Riemann hypothesis. The proof is
carried out by explicit construction of such polynomials. To prove the Riemann
hypothesis for a certain class of invariant polynomials, we establish an
analogue of the Enestr"om-Kakeya theorem.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 09:17:42 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Chinen",
"Koji",
""
]
] |
0704.3904 | Fabien Mathieu | Anh-Tuan Gai (INRIA Rocquencourt), Dmitry Lebedev (FT R&D), Fabien
Mathieu (FT R&D), Fabien De Montgolfier (LIAFA), Julien Reynier (LIENS),
Laurent Viennot (INRIA Rocquencourt) | Acyclic Preference Systems in P2P Networks | null | null | null | null | cs.DS cs.GT | null | In this work we study preference systems natural for the Peer-to-Peer
paradigm. Most of them fall in three categories: global, symmetric and
complementary. All these systems share an acyclicity property. As a
consequence, they admit a stable (or Pareto efficient) configuration, where no
participant can collaborate with better partners than their current ones. We
analyze the representation of the such preference systems and show that any
acyclic system can be represented with a symmetric mark matrix. This gives a
method to merge acyclic preference systems and retain the acyclicity. We also
consider such properties of the corresponding collaboration graph, as
clustering coefficient and diameter. In particular, studying the example of
preferences based on real latency measurements, we observe that its stable
configuration is a small-world graph.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 09:26:39 GMT"
},
{
"version": "v2",
"created": "Wed, 2 May 2007 13:07:31 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Gai",
"Anh-Tuan",
"",
"INRIA Rocquencourt"
],
[
"Lebedev",
"Dmitry",
"",
"FT R&D"
],
[
"Mathieu",
"Fabien",
"",
"FT R&D"
],
[
"De Montgolfier",
"Fabien",
"",
"LIAFA"
],
[
"Reynier",
"Julien",
"",
"LIENS"
],
[
"Viennot",
"Laurent",
"",
"INRIA Rocquencourt"
]
] |
0704.3905 | Marc Schoenauer | Christian Gagn\'e (INFORMATIQUE WGZ INC.), Mich\`ele Sebag (INRIA
Futurs), Marc Schoenauer (INRIA Futurs), Marco Tomassini (ISI) | Ensemble Learning for Free with Evolutionary Algorithms ? | null | Dans GECCO (2007) | null | null | cs.AI | null | Evolutionary Learning proceeds by evolving a population of classifiers, from
which it generally returns (with some notable exceptions) the single
best-of-run classifier as final result. In the meanwhile, Ensemble Learning,
one of the most efficient approaches in supervised Machine Learning for the
last decade, proceeds by building a population of diverse classifiers. Ensemble
Learning with Evolutionary Computation thus receives increasing attention. The
Evolutionary Ensemble Learning (EEL) approach presented in this paper features
two contributions. First, a new fitness function, inspired by co-evolution and
enforcing the classifier diversity, is presented. Further, a new selection
criterion based on the classification margin is proposed. This criterion is
used to extract the classifier ensemble from the final population only
(Off-line) or incrementally along evolution (On-line). Experiments on a set of
benchmark problems show that Off-line outperforms single-hypothesis
evolutionary learning and state-of-art Boosting and generates smaller
classifier ensembles.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 09:29:22 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Gagné",
"Christian",
"",
"INFORMATIQUE WGZ INC."
],
[
"Sebag",
"Michèle",
"",
"INRIA\n Futurs"
],
[
"Schoenauer",
"Marc",
"",
"INRIA Futurs"
],
[
"Tomassini",
"Marco",
"",
"ISI"
]
] |
0704.3906 | Michael M. Wolf | M.M. Wolf, F. Verstraete, M.B. Hastings, J.I. Cirac | Area laws in quantum systems: mutual information and correlations | 5 pages, 2 figures, published version with appendix | Phys. Rev. Lett. 100, 070502 (2008) | 10.1103/PhysRevLett.100.070502 | null | quant-ph cond-mat.stat-mech | null | The holographic principle states that on a fundamental level the information
content of a region should depend on its surface area rather than on its
volume. This counterintuitive idea which has its roots in the nonextensive
nature of black-hole entropy serves as a guiding principle in the search for
the fundamental laws of Planck-scale physics. In this paper we show that a
similar phenomenon emerges from the established laws of classical and quantum
physics: the information contained in part of a system in thermal equilibrium
obeys an area law. While the maximal information per unit area depends
classically only on the number of microscopic degrees of freedom, it may
diverge as the inverse temperature in quantum systems. A rigorous relation
between area laws and correlations is established and their explicit behavior
is revealed for a large class of quantum many-body states beyond equilibrium
systems.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 09:36:44 GMT"
},
{
"version": "v2",
"created": "Mon, 10 Mar 2008 18:24:31 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Wolf",
"M. M.",
""
],
[
"Verstraete",
"F.",
""
],
[
"Hastings",
"M. B.",
""
],
[
"Cirac",
"J. I.",
""
]
] |
0704.3907 | Lucas Lamata | Lucas Lamata | Developments in entanglement theory and applications to relevant
physical systems | Ph.D. Thesis, April 2007, Universidad Autonoma de Madrid | null | null | null | quant-ph | null | This Thesis is devoted to the analysis of entanglement in relevant physical
systems. Entanglement is the conducting theme of this research, though I do not
dedicate to a single topic, but consider a wide scope of physical situations. I
have followed mainly three lines of research for this Thesis, with a series of
different works each, which are, Entanglement and Relativistic Quantum Theory,
Continuous-variable entanglement, and Multipartite entanglement.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 09:37:41 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Lamata",
"Lucas",
""
]
] |
0704.3908 | Margarita Sharina | M.E. Sharina (SAO RAS), Th.H. Puzia (Herzberg Institute of
Astrophysics), A.S. Krylatyh (Kazan State University) | A globular cluster in the dwarf galaxy Sextans B | 13 pages, 4 figures, 3 tables, Astrophysical Bulletin, accepted | null | 10.1134/S1990341307030029 | null | astro-ph | null | We present spectroscopic observations of a massive globular cluster in the
dwarf irregular galaxy Sextans B, discovered by us on Hubble Space Telescope
Wide Field and Planetary Camera 2 (HST WFPC2) images. Long-slit spectra were
obtained with the SCORPIO spectrograph on the the 6-m telescope at the Special
Astrophysical observatory of the Russian Academy of Sciences. We determine age,
metallicity and alpha-element abundance ratio for the globular cluster to be $
2 \pm 1$ Gyr, $-1.35 \pm 0.25$ dex, and $ 0.1 \pm 0.1$ dex, respectively. Main
photometric and structural parameters of it were determined using our surface
photometry on the HST images. The mass ($\sim 10^5 M \sun$), luminosity and
structural parameters appear to be typical for the globular clusters in our own
Galaxy. Our findings shed a new light on the evolutionary history of Sextans B.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 10:05:55 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Sharina",
"M. E.",
"",
"SAO RAS"
],
[
"Puzia",
"Th. H.",
"",
"Herzberg Institute of\n Astrophysics"
],
[
"Krylatyh",
"A. S.",
"",
"Kazan State University"
]
] |
0704.3909 | Natalia Panikashvili | D0 Collaboration: V. Abazov, et al | Measurement of the Lambda_b lifetime in the exclusive decay Lambda_b to
J/psi Lambda | This version has been accepted for publication in Physical Review
Letters | Phys.Rev.Lett.99:142001,2007 | 10.1103/PhysRevLett.99.142001 | FERMILAB-PUB-07/094-E | hep-ex | null | We have measured the Lambda_b lifetime using the exclusive decay Lambda_b to
J/psi Lambda, based on 1.2 fb-1 of data collected with the D0 detector during
2002-2006. From 171 reconstructed Lambda_b decays, where the J/psi and Lambda
are identified via the decays J/psi to mu+ mu- and Lambda to p pi, we measured
the Lambda_b lifetime to be tau(Lambda_b) = 1.218(+0.130,-0.115)(stat) +/-
0.042(syst)ps. We also measured the B0 lifetime in the decay B0 to J/psi(mu+
mu-)K0_S(pi+ pi-) to be tau(B0) = 1.501(+0.078,-0.074)(stat) +/ -0.050(syst)ps,
yielding a lifetime ratio of tau(Lambda_b)/tau(B0) = 0.811(+0.096,-0.087)(stat)
+/ -0.034(syst). These measurements are consistent with the current world
averages and support the shorter lifetime of the Lambda_b with respect to B
mesons, in contrast to another recent measurement of significant precision.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 09:44:44 GMT"
},
{
"version": "v2",
"created": "Thu, 30 Aug 2007 08:39:17 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"D0 Collaboration",
"",
""
],
[
"Abazov",
"V.",
""
]
] |
0704.3910 | Guillaume Dubus | P. d'Avezac, G. Dubus, B. Giebels | Cascading on extragalactic background light | 5 pages, to be published as a research note in A&A | Astron.Astrophys.469:857-860,2007 | 10.1051/0004-6361:20066712 | null | astro-ph | null | High-energy gamma-rays propagating in the intergalactic medium can interact
with background infrared photons to produce e+e- pairs, resulting in the
absorption of the intrinsic gamma-ray spectrum. TeV observations of the distant
blazar 1ES 1101-232 were thus recently used to put an upper limit on the
infrared extragalactic background light density. The created pairs can
upscatter background photons to high energies, which in turn may pair produce,
thereby initiating a cascade. The pairs diffuse on the extragalactic magnetic
field (EMF) and cascade emission has been suggested as a means for measuring
its intensity. Limits on the IR background and EMF are reconsidered taking into
account cascade emissions. The cascade equations are solved numerically.
Assuming a power-law intrinsic spectrum, the observed 100 MeV - 100 TeV
spectrum is found as a function of the intrinsic spectral index and the
intensity of the EMF. Cascades emit mainly at or below 100 GeV. The observed
TeV spectrum appears softer than for pure absorption when cascade emission is
taken into account. The upper limit on the IR photon background is found to be
robust. Inversely, the intrinsic spectra needed to fit the TeV data are
uncomfortably hard when cascade emission makes a significant contribution to
the observed spectrum. An EMF intensity around 1e-8 nG leads to a
characteristic spectral hump in the GLAST band. Higher EMF intensities divert
the pairs away from the line-of-sight and the cascade contribution to the
spectrum becomes negligible.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 09:55:01 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"d'Avezac",
"P.",
""
],
[
"Dubus",
"G.",
""
],
[
"Giebels",
"B.",
""
]
] |
0704.3911 | Robinson Edward Raja Chandiraraj | C. R. E. Raja | Distal actions and ergodic actions on compact groups | null | null | null | null | math.DS | null | Let $K$ be a compact metrizable group and $\Ga$ be a group of automorphisms
of $K$. We first show that each $\ap \in \Ga$ is distal on $K$ implies $\Ga$
itself is distal on $K$, a local to global correspondence provided $\Ga$ is a
generalized $\ov{FC}$-group or $K$ is a connected finite-dimensional group. We
show that $\Ga$ contains an ergodic automorphism when $\Ga$ is nilpotent and
ergodic on a connected finite-dimensional compact abelian group $K$.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 09:55:50 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Raja",
"C. R. E.",
""
]
] |
0704.3912 | Cinzia Casagrande | C. Casagrande | Quasi elementary contractions of Fano manifolds | Final version, minor changes, to appear in Compositio Mathematica | null | null | null | math.AG | null | Let X be a smooth complex Fano variety. We define and study 'quasi
elementary' contractions of fiber type f: X -> Y. These have the property that
rho(X) is at most rho(Y)+rho(F), where rho is the Picard number and F is a
general fiber of f. In particular any elementary extremal contraction of fiber
type is quasi elementary. We show that if Y has dimension at most 3 and Picard
number at least 4, then Y is smooth and Fano; if moreover rho(Y) is at least 6,
then X is a product. This yields sharp bounds on rho(X) when dim(X)=4 and X has
a quasi elementary contraction, and other applications in higher dimensions.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 10:09:24 GMT"
},
{
"version": "v2",
"created": "Fri, 18 Apr 2008 11:10:39 GMT"
}
] | 2008-04-18T00:00:00 | [
[
"Casagrande",
"C.",
""
]
] |
0704.3913 | Wei-shui Xu | Yi-hong Gao, Jonathan P. Shock, Wei-shui Xu and Ding-fang Zeng | A Note on Chiral Symmetry Breaking from Intersecting Branes | 16 pp, minor changes, to appear PRD | Phys.Rev.D76:046003,2007 | 10.1103/PhysRevD.76.046003 | null | hep-th | null | In this paper, we will consider the chiral symmetry breaking in the
holographic model constructed from the intersecting brane configuration, and
investigate the Nambu-Goldstone bosons associated with this symmetry breaking.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 10:43:35 GMT"
},
{
"version": "v2",
"created": "Tue, 12 Jun 2007 16:55:17 GMT"
},
{
"version": "v3",
"created": "Wed, 1 Aug 2007 12:23:48 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Gao",
"Yi-hong",
""
],
[
"Shock",
"Jonathan P.",
""
],
[
"Xu",
"Wei-shui",
""
],
[
"Zeng",
"Ding-fang",
""
]
] |
0704.3914 | Nigel Glover | S. D. Badger (Saclay, SPhT), E. W. N. Glover (IPPP, Durham U.), Kasper
Risager (Bohr Inst.) | One-loop phi-MHV amplitudes using the unitarity bootstrap | 40 pages, 11 eps figures, JHEP3 class, references added | JHEP 0707:066,2007 | 10.1088/1126-6708/2007/07/066 | IPPP/07/12, SACLAY-SPHT-T07/044 | hep-ph | null | We consider a Higgs boson coupled to gluons via the five-dimensional
effective operator H Tr G_{munu}G^{munu} produced by considering the heavy top
quark limit of the one-loop coupling of Higgs and gluons in the standard model.
We treat H as the real part of a complex field phi that couples to the selfdual
gluon field strengths and compute the one-loop corrections to amplitudes
involving phi, two colour adjacent negative helicity gluons and an arbitrary
number of positive helicity gluons - the so-called phi-MHV amplitudes. We use
four-dimensional unitarity to construct the cut-containing contributions and
the recently developed recursion relations to obtain the rational contribution
for an arbitrary number of external gluons. We solve the recursion relations
and give explicit results for up to four external gluons. These amplitudes are
relevant for Higgs plus jet production via gluon fusion in the limit where the
top quark mass is large compared to all other scales in the problem.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 10:49:31 GMT"
},
{
"version": "v2",
"created": "Mon, 11 Jun 2007 08:26:56 GMT"
},
{
"version": "v3",
"created": "Mon, 2 Jul 2007 21:36:42 GMT"
}
] | 2009-04-21T00:00:00 | [
[
"Badger",
"S. D.",
"",
"Saclay, SPhT"
],
[
"Glover",
"E. W. N.",
"",
"IPPP, Durham U."
],
[
"Risager",
"Kasper",
"",
"Bohr Inst."
]
] |
0704.3915 | Andrea Borch | Andrea Borch, Rainer Spurzem, Jarrod Hurley | NBODY meets stellar population - The HYDE-PARC Project | 21 pages. submitted to A&A | null | null | null | astro-ph | null | N-body simulations give us a rough idea of how the shape of a simulated
object appears in three-dimensional space. From an observational point of view
this may give us a misleading picture. The faint stars may be the most common
stars in the system but the morphological information obtained by observations
of an object may be dominated by the color properties of the bright stars. Due
to dynamical effects, such as energy equipartition, different masses of stars
may populate different regions in the object. Since stars are evolving in mass
the stellar evolution may also influence the dynamics of the system. Hence, if
one is interested in simulating what the morphology will look like through a
telescope, one needs to simulate in addition evolving stars and weight them by
their luminosity. Therefore we need to combine simulations of the dynamical
evolution and a stellar population synthesis at the same time. For the
dynamical evolution part we use a parallel version of a direct N-body code,
NBODY6++. This code also includes stellar evolution. We link the parameters
from this stellar evolution routine to the BaSeL 2.0 stellar library. For
isolated clusters we found results assimilable to standard stellar population
synthesis codes such as the PEGASE code. For clusters in a tidal field we found
that the integrated colors become relatively bluer due to energy equipartition
effects. In the time shortly before dissolution of the cluster the stellar M/L
ratio becomes lower compared to isolated clusters. We compared the results of
our simulations to integrated spectra of galactic globular clusters. For the
cluster NGC 1851 we found good agreement between simulation and observation.
For extragalactic clusters in M81 and M31 we looked at medium band spectral
energy distributions and found for some clusters also a good agreement.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 10:48:37 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Borch",
"Andrea",
""
],
[
"Spurzem",
"Rainer",
""
],
[
"Hurley",
"Jarrod",
""
]
] |
0704.3916 | Outi Elina Maasalo | Outi Elina Maasalo | The Gehring Lemma in Metric Spaces | 16 pages; typos corrected | null | null | null | math.CA math.AP | null | We present a proof for the Gehring lemma in a metric measure space endowed
with a doubling measure. As an application we show the self improving property
of Muckenhoupt weights.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 10:57:09 GMT"
},
{
"version": "v2",
"created": "Fri, 24 Aug 2007 07:58:51 GMT"
},
{
"version": "v3",
"created": "Tue, 15 Jan 2008 12:39:15 GMT"
}
] | 2008-01-15T00:00:00 | [
[
"Maasalo",
"Outi Elina",
""
]
] |
0704.3917 | Maria Vittoria Garzelli | M.V. Garzelli | A fully microscopical simulation of nuclear collisions by a new QMD
model | 5 pages, 7 figures. Talk presented at ND2007, International
Conference on Nuclear Data for Science and Technology, Nice, France, April 22
- 27 2007 | Proceedings of ND2007, International Conference of Nuclear Data
for Science and Technology, editors O. Bersillon, F. Gunsing, E. Bauge, R.
Jacqmin and S. Leray, EDP Sciences (2008), 1129 - 1132 | 10.1051/ndata:07673 | null | nucl-th | null | Nucleon-ion and ion-ion collisions at non relativistic bombarding energies
can be described by means of Monte Carlo approaches, such as those based on the
Quantum Molecular Dynamics (QMD) model. We have developed a QMD code, to
simulate the fast stage of heavy-ion reactions, and we have coupled it to the
de-excitation module available in the FLUKA Monte Carlo transport and
interaction code. The results presented in this work span the projectile
bombarding energy range within 200 - 600 MeV/A, allowing to investigate the
capabilities and limits of our non-relativistic QMD approach.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 11:55:10 GMT"
}
] | 2008-09-14T00:00:00 | [
[
"Garzelli",
"M. V.",
""
]
] |
0704.3918 | Antoine Van Proeyen | Kostas Skenderis, Paul K. Townsend and Antoine Van Proeyen | Domain-wall/Cosmology correspondence in adS/dS supergravity | 21 pages;v2: rewritten to clarify the link with fake supergravity --
main results unchanged; v3: typos corrected, two refs added, JHEP version | JHEP0708:036,2007 | 10.1088/1126-6708/2007/08/036 | DAMTP-2007-40, ITFA-2007-16, KUL-TF-07/09 | hep-th | null | We realize the domain-wall/cosmology correspondence for
(pseudo)supersymmetric domain walls (cosmologies) in the context of
four-dimensional supergravity. The OSp(2|4)-invariant anti-de Sitter (adS)
vacuum of a particular N=2 Maxwell-Einstein supergravity theory is shown to
correspond to the OSp(2^*|2,2)-invariant de Sitter (dS) vacuum of a particular
pseudo-supergravity model, with `twisted' reality conditions on spinors. More
generally, supersymmetric domain walls of the former model correspond to
pseudo-supersymmetric cosmologies of the latter model, with time-dependent
pseudo-Killing spinors that we give explicitly.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 19:58:39 GMT"
},
{
"version": "v2",
"created": "Tue, 26 Jun 2007 10:05:16 GMT"
},
{
"version": "v3",
"created": "Tue, 14 Aug 2007 19:25:01 GMT"
}
] | 2010-02-17T00:00:00 | [
[
"Skenderis",
"Kostas",
""
],
[
"Townsend",
"Paul K.",
""
],
[
"Van Proeyen",
"Antoine",
""
]
] |
0704.3919 | Andria Rogava | Andria Rogava, Grigol Gogoberidze and Stefaan Poedts | On over-reflection and generation of Gravito-Alfven waves in solar-type
stars | 20 pages (preprint format), 4 figures; to appear in The Astrophysical
Journal (August 1, 2007, v664, N2 issue) | Astrophys.J.664:1221-1227,2007 | 10.1086/518824 | null | astro-ph | null | The dynamics of linear perturbations is studied in magnetized plasma shear
flows with a constant shearing rate and with gravity-induced stratification.
The general set of linearized equations is derived and the two-dimensional case
is considered in detail. The Boussinesq approximation is used in order to
examine relatively small-scale perturbations of low-frequency modes:
Gravito-Alfven waves (GAW) and Entropy Mode (EM) perturbations. It is shown
that for flows with arbitrary shearing rate there exists a finite time interval
of non-adiabatic evolution of the perturbations. The non-adiabatic behavior
manifests itself in a twofold way, viz. by the over-reflection of the GAWs and
by the generation of GAWs from EM perturbations. It is shown that these
phenomena act as efficient transformers of the equilibrium flow energy into the
energy of the perturbations for moderate and high shearing rate solar plasma
flows. Efficient generation of GAW by EM takes place for shearing rates about
an order of magnitude smaller than necessary for development of a shear
instability. The latter fact could have important consequences for the problem
of angular momentum redistribution within the Sun and solar-type stars.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 11:38:22 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Rogava",
"Andria",
""
],
[
"Gogoberidze",
"Grigol",
""
],
[
"Poedts",
"Stefaan",
""
]
] |
0704.3920 | Seong Chan Park | Seong Chan Park (Seoul National University) | Orbifold GUT inflation | 12 pages, 6 figures, JCAP accepted version | JCAP0711:001,2007 | 10.1088/1475-7516/2007/11/001 | null | hep-th astro-ph gr-qc hep-ph | null | We consider a scenario of cosmological inflation coming from a grand unified
theory in higher dimensional orbifold. Flatness of the potential is
automatically guaranteed in this orbifold setup thanks to the nonlocality of
the Wilson line on higher dimensions and the local quantum gravitational
corrections are exponentially suppressed. The spectral index of scalar
perturbation (n_s =0.92 - 0.97) and a significant production of gravitational
waves are predicted (r= T/S= 0.01 - 0.12) in the perturbative regime of gauge
interaction, (1/g_4 = (5-20) X 2 pi R Mpl) where the size of compactification
is constrained (R Mpl = 20- 45) by the measurement of scalar power spectrum
(Delta_R = 5 X 10^-5).
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 12:17:25 GMT"
},
{
"version": "v2",
"created": "Wed, 17 Oct 2007 16:53:47 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Park",
"Seong Chan",
"",
"Seoul National University"
]
] |
0704.3921 | Li Ma | Li Ma, Lin Zhao | Sharp thresholds of blow-up and global existence for the coupled
nonlinear Schrodinger system | 21 pages | null | 10.1063/1.2939238 | null | math.AP math.DG | null | In this paper, we establish two new types of invariant sets for the coupled
nonlinear Schrodinger system on $\mathbb{R}^n$, and derive two sharp thresholds
of blow-up and global existence for its solution. Some analogous results for
the nonlinear Schrodinger system posed on the hyperbolic space $\mathbb{H}^n$
and on the standard 2-sphere $\mathbb{S}^2$ are also presented. Our arguments
and constructions are improvements of some previous works on this direction. At
the end, we give some heuristic analysis about the strong instability of the
solitary waves.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 12:03:03 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Ma",
"Li",
""
],
[
"Zhao",
"Lin",
""
]
] |
0704.3922 | Nicolas Fournier | Nicolas Fournier | Smoothness of the law of some one-dimensional jumping S.D.E.s with
non-constant rate of jump | null | null | null | null | math.PR | null | We consider a one-dimensional jumping Markov process $\{X^x_t\}_{t \geq 0}$,
solving a Poisson-driven stochastic differential equation. We prove that the
law of $X^x_t$ admits a smooth density for $t>0$, under some regularity and
non-degeneracy assumptions on the coefficients of the S.D.E. To our knowledge,
our result is the first one including the important case of a non-constant rate
of jump. The main difficulty is that in such a case, the map $x \mapsto X^x_t$
is not smooth. This seems to make impossible the use of Malliavin calculus
techniques. To overcome this problem, we introduce a new method, in which the
propagation of the smoothness of the density is obtained by analytic arguments.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 12:05:21 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Fournier",
"Nicolas",
""
]
] |
0704.3923 | Prabuddha Sanyal | Prabuddha Sanyal, Subhra Sen Gupta, Nandan Pakhira, H. R.
Krishnamurthy, D. D. Sarma and T. V. Ramakrishnan | Unusual doping and temperature dependence of photoemission spectra from
manganites | 5 pages, 3 figures | null | 10.1209/0295-5075/82/47010 | null | cond-mat.str-el cond-mat.mtrl-sci | null | A recent, major, puzzle in the core-level photoemission spectra of doped
manganites is the observation of a 1-2 eV wide shoulder with intensity varying
with temperature T as the square of the magnetization over a T scale of order
200K, an order of magnitude less than electronic energies. This is addressed
and resolved here, by extending a recently proposed two electron fluid l-b
model for these systems to include core-hole effects. The shoulder arises from
a rapid redistribution of e_g electron density, as a function of T, between the
highly localized (l) and band-like (b) states. Furthermore, our theory leads to
a correspondence between spectral changes due to increasing doping and
decreasing T, as experimentally observed.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:05:20 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Sanyal",
"Prabuddha",
""
],
[
"Gupta",
"Subhra Sen",
""
],
[
"Pakhira",
"Nandan",
""
],
[
"Krishnamurthy",
"H. R.",
""
],
[
"Sarma",
"D. D.",
""
],
[
"Ramakrishnan",
"T. V.",
""
]
] |
0704.3924 | Lukasz Andrzej Glinka | B.M. Barbashov, L.A. Glinka, V.N. Pervushin, A.F. Zakharov | Higgs effect in Conformal Cosmology & Supernova Data | 8 pages, talk on Tenth European Meeting From the Planck Scale to the
Electroweak Scale Warsaw, Poland, June 9 - 13, 2007 PLANCK'07 | null | null | null | hep-ph | null | The formulation of the Higgs effect is studied in the
Glashow--Weinberg--Salam Standard Model, where the constant part of the Higgs
potential is identified with the zeroth mode of the Higgs field. In this model,
the Coleman--Weinberg effective potential obtained from the vacuum--vacuum
transition amplitude is equal to unity at the extremum. This extremum
immediately removes tremendous vacuum cosmological density and predicts mass of
Higgs field. In this model, the kinetic energy density of the Higgs field and
any scalar field can be treated as the rigid state origin that explains
Supernova data in the conformal cosmology without the $\Lambda$ term.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 12:47:49 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Barbashov",
"B. M.",
""
],
[
"Glinka",
"L. A.",
""
],
[
"Pervushin",
"V. N.",
""
],
[
"Zakharov",
"A. F.",
""
]
] |
0704.3925 | Peter Kalberla MW | P.M.W. Kalberla, L. Dedes, J. Kerp, U. Haud | Dark matter in the Milky Way, II. the HI gas distribution as a tracer of
the gravitational potential | 19 pages, 21 figures, accepted for publication by A&A | null | 10.1051/0004-6361:20066362 | null | astro-ph | null | Context. Gas within a galaxy is forced to establish pressure balance against
gravitational forces. The shape of an unperturbed gaseous disk can be used to
constrain dark matter models. Aims. We derive the 3-D HI volume density
distribution for the Milky Way out to a galactocentric radius of 40 kpc and a
height of 20 kpc to constrain the Galactic mass distribution. Methods. We used
the Leiden/Argentine/Bonn all sky 21-cm line survey. The transformation from
brightness temperatures to densities depends on the rotation curve. We explored
several models, reflecting different dark matter distributions. Each of these
models was set up to solve the combined Poisson-Boltzmann equation in a
self-consistent way and optimized to reproduce the observed flaring. Results.
Besides a massive extended halo of M ~ 1.8 10^{12} Msun, we find a
self-gravitating dark matter disk with M=2 to 3 10^{11} Msun, including a dark
matter ring at 13 < R < 18.5 kpc with M = 2.2 to 2.8 10^{10} Msun. The
existence of the ring was previously postulated from EGRET data and coincides
with a giant stellar structure that surrounds the Galaxy. The resulting Milky
Way rotation curve is flat up to R~27 kpc and slowly decreases outwards. The
\hi gas layer is strongly flaring. The HWHM scale height is 60 pc at R = 4 kpc
and increases to ~2700$ pc at R=40 kpc. Spiral arms cause a noticeable imprint
on the gravitational field, at least out to R = 30 kpc. Conclusions. Our mass
model supports previous proposals that the giant stellar ring structure is due
to a merging dwarf galaxy. The fact that the majority of the dark matter in the
Milky Way for $R \la 40$ kpc can be successfully modeled by a self-gravitating
isothermal disk raises the question of whether this massive disk may have been
caused by similar merger events in the past.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 12:18:53 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Kalberla",
"P. M. W.",
""
],
[
"Dedes",
"L.",
""
],
[
"Kerp",
"J.",
""
],
[
"Haud",
"U.",
""
]
] |
0704.3926 | Wenhua Hai | Wenhua Hai, Guishu Chong, Jianwen Song | Stabilities of one-dimensional stationary states of Bose-Einstein
condensates | 12 pages | Phys. Lett. A372, 2558 (2008) | 10.1016/j.physleta.2007.12.029 | null | quant-ph | null | We explore the dynamical stabilities of a quasi-one dimensional (1D)
Bose-Einstein condensate (BEC) consisting of fixed $N$ atoms with
time-independent external potential. For the stationary states with zero flow
density the general solution of the perturbed time evolution equation is
constructed, and the stability criterions concerning the initial conditions and
system parameters are established. Taking the lattice potential case as an
example, the stability and instability regions on the parameter space are
found. The results suggest a method for selecting experimental parameters and
adjusting initial conditions to suppress the instabilities.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 12:23:24 GMT"
},
{
"version": "v2",
"created": "Wed, 16 Apr 2008 08:18:37 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Hai",
"Wenhua",
""
],
[
"Chong",
"Guishu",
""
],
[
"Song",
"Jianwen",
""
]
] |
0704.3927 | D. N. Basu | P. Roy Chowdhury, D.N. Basu, C. Samanta | Alpha decay chains from element 113 | 3 pages | Phys.Rev.C75:047306,2007 | 10.1103/PhysRevC.75.047306 | null | nucl-th nucl-ex | null | Theoretical estimates of $\alpha$-decay half lives of several nuclei in the
decay from element 113 are presented. Calculations in a WKB framework using
DDM3Y interaction and experimental Q-values are in good agreement with the
experimental data. Half life calculations are found to be quite sensitive to
the Q-values and angular momenta transfers. Calculated decay lifetime
decreases, owing to more penetrability as well as thinner barrier, as Q-value
increases. Deviations to this predominant behaviour observed in some recent
experimental data may be attributed to non zero spin-parities in some cases.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:47:01 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Chowdhury",
"P. Roy",
""
],
[
"Basu",
"D. N.",
""
],
[
"Samanta",
"C.",
""
]
] |
0704.3928 | Ian Appelbaum | Biqin Huang (1), Douwe J. Monsma (2), and Ian Appelbaum (1) ((1)
University of Delaware, (2) Cambridge NanoTech Inc.) | Spin lifetime in silicon in the presence of parasitic electronic effects | null | J. Appl. Phys. 102, 013901 (2007) | 10.1063/1.2750411 | null | cond-mat.mtrl-sci cond-mat.other | null | A hybrid ferromagnet/semiconductor device is used to determine a lower bound
on the spin lifetime for conduction electrons in silicon. We use spin
precession to self-consistently measure the drift velocity vs. drift field of
spin-polarized electrons and use this electronic control to change the transit
time between electron injection and detection. A measurement of normalized
magnetocurrent as a function of drift velocity is used with a simple
exponential-decay model to argue that the lifetime obtained (~2 ns) is
artificially lowered by electronic effects and is likely orders of magnitude
higher.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:21:02 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Huang",
"Biqin",
""
],
[
"Monsma",
"Douwe J.",
""
],
[
"Appelbaum",
"Ian",
""
]
] |
0704.3929 | Hideki Maekawa | Hideki Maekawa, Kohsuke Tsubakihara, Hiroshi Matsumiya, Akira Ohnishi | Cascade hypernuclear production spectra at J-PARC | 6 pages, 7 figures | null | null | null | nucl-th | null | We predict cascade hypernuclear production spectra expected in the
forthcoming J-PARC experiment. In the Green's function method of the distorted
wave impulse wave approximation with the local optimal Fermi averaging
t-matrix, we can describe the Xi production spectra in the continuum and bound
state region reasonably well. Predictions to the high resonlution spectra at
J-PARC suggest hat we should observe Xi bound state peak structure in (K-,K+)
spectra in light nuclear targets such as 12C and 27Al.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 12:35:00 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Maekawa",
"Hideki",
""
],
[
"Tsubakihara",
"Kohsuke",
""
],
[
"Matsumiya",
"Hiroshi",
""
],
[
"Ohnishi",
"Akira",
""
]
] |
0704.3930 | Ferenc Gl\"uck | J. Bonn, K. Eitel, F. Gl\"uck, D. Sevilla-Sanchez and N. Titov | The KATRIN sensitivity to the neutrino mass and to right-handed currents
in beta decay | 4 pages, 2 figures, 12 references | Phys.Lett.B703:310-312,2011 | 10.1016/j.physletb.2011.08.005 | null | hep-ph | null | The aim of the KArlsruhe TRItium Neutrino experiment KATRIN is the
determination of the absolute neutrino mass scale down to 0.2 eV, with
essentially smaller model dependence than from cosmology and neutrinoless
double beta decay. For this purpose, the integral electron energy spectrum is
measured close to the endpoint of molecular tritium beta decay. The endpoint,
together with the neutrino mass, should be fitted from the KATRIN data as a
free parameter. The right-handed couplings change the electron energy spectrum
close to the endpoint, therefore they have some effect also to the precise
neutrino mass determination. The statistical calculations show that, using the
endpoint as a free parameter, the unaccounted right-handed couplings
constrained by many beta decay experiments can change the fitted neutrino mass
value, relative to the true neutrino mass, by not larger than about 5-10 %.
Using, incorrectly, the endpoint as a fixed input parameter, the above change
of the neutrino mass can be much larger, order of 100 %, and for some cases it
can happen that for large true neutrino mass value the fitted neutrino mass
squared is negative. Publications using fixed endpoint and presenting large
right-handed coupling effects to the neutrino mass determination are not
relevant for the KATRIN experiment.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 12:53:21 GMT"
}
] | 2011-09-07T00:00:00 | [
[
"Bonn",
"J.",
""
],
[
"Eitel",
"K.",
""
],
[
"Glück",
"F.",
""
],
[
"Sevilla-Sanchez",
"D.",
""
],
[
"Titov",
"N.",
""
]
] |
0704.3931 | Martin Lange | Roland Axelsson, Martin Lange, and Rafal Somla | The Complexity of Model Checking Higher-Order Fixpoint Logic | 33 pages, 2 figures, to be published in Logical Methods in Computer
Science | Logical Methods in Computer Science, Volume 3, Issue 2 (June 29,
2007) lmcs:754 | 10.2168/LMCS-3(2:7)2007 | null | cs.LO | null | Higher-Order Fixpoint Logic (HFL) is a hybrid of the simply typed
\lambda-calculus and the modal \lambda-calculus. This makes it a highly
expressive temporal logic that is capable of expressing various interesting
correctness properties of programs that are not expressible in the modal
\lambda-calculus.
This paper provides complexity results for its model checking problem. In
particular we consider those fragments of HFL built by using only types of
bounded order k and arity m. We establish k-fold exponential time completeness
for model checking each such fragment. For the upper bound we use fixpoint
elimination to obtain reachability games that are singly-exponential in the
size of the formula and k-fold exponential in the size of the underlying
transition system. These games can be solved in deterministic linear time. As a
simple consequence, we obtain an exponential time upper bound on the expression
complexity of each such fragment.
The lower bound is established by a reduction from the word problem for
alternating (k-1)-fold exponential space bounded Turing Machines. Since there
are fixed machines of that type whose word problems are already hard with
respect to k-fold exponential time, we obtain, as a corollary, k-fold
exponential time completeness for the data complexity of our fragments of HFL,
provided m exceeds 3. This also yields a hierarchy result in expressive power.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:09:20 GMT"
},
{
"version": "v2",
"created": "Fri, 29 Jun 2007 12:15:42 GMT"
}
] | 2015-07-01T00:00:00 | [
[
"Axelsson",
"Roland",
""
],
[
"Lange",
"Martin",
""
],
[
"Somla",
"Rafal",
""
]
] |
0704.3932 | Oscar Esquivel | O. Esquivel and B. Fuchs | Dynamical friction force exerted on spherical bodies | 5 pages, 2 figures, accepted in MNRAS | Mon.Not.Roy.Astron.Soc.378:1191-1195,2007 | 10.1111/j.1365-2966.2007.11870.x | null | astro-ph | null | We present a rigorous calculation of the dynamical friction force exerted on
a spherical massive perturber moving through an infinite homogenous system of
field stars. By calculating the shape and mass of the polarization cloud
induced by the perturber in the background system, which decelerates the motion
of the perturber, we recover Chandrasekhar's drag force law with a modified
Coulomb logarithm. As concrete examples we calculate the drag force exerted on
a Plummer sphere or a sphere with the density distribution of a Hernquist
profile. It is shown that the shape of the perturber affects only the exact
form of the Coulomb logarithm. The latter converges on small scales, because
encounters of the test and field stars with impact parameters less than the
size of the massive perturber become inefficient. We confirm this way earlier
results based on the impulse approximation of small angle scatterings.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:08:45 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Esquivel",
"O.",
""
],
[
"Fuchs",
"B.",
""
]
] |
0704.3933 | Stijn Bruers Mr | Stijn Bruers | Testing entropy production hypotheses in non-linear steady states | null | null | null | null | physics.chem-ph | null | In the last few decades, some hypotheses for entropy production (EP)
principles have been forwarded as possible candidates for organizational
principles in non-linear non- equilibrium systems. Two important hypotheses
will be studied: the maximum entropy production (MaxEP) principle that claims
that the selected steady state has the highest EP, and the gradient response
principle that claims that the EP of the selected steady state (maximally)
increases when the external thermodynamic driving force increases. We will
formulate these hypotheses more rigorously and present a simple chemical
reaction model to test these hypotheses. With the help of this model, we will
clearly demonstrate that there are different MaxEP hypotheses being discussed
in the literature and we will look at some parts in the literature where these
differences are not always clarified. Furthermore, our chemical model will be a
general counter example to all of these MaxEP and gradient response hypotheses.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:15:09 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bruers",
"Stijn",
""
]
] |
0704.3934 | Sascha Bornhauser | Sascha Bornhauser and Manuel Drees | Signals of Very High Energy Neutralinos in Future Cosmic Ray Detectors | 14 pages, 2 figures | Phys.Lett.B650:407-415,2007 | 10.1016/j.physletb.2007.05.048 | null | hep-ph | null | ``Top--down'' models explain the observation of ultra high energy cosmic rays
(UHECR; $E \gsim 5 \cdot 10^{19}$ eV) through the decay of very massive,
long--lived ``$X$ particles''. If superparticles with masses near a TeV exist,
$X$ decays also lead to a significant flux of very energetic neutralinos,
assumed to be the (stable or long--lived) lightest superparticles. There is a
range of energies where neutrinos get absorbed in the Earth, but neutralinos
can still traverse it. These neutralinos could in principle be detected. We
calculate the detection rate in planned experiments such as OWL and EUSO. For
bino--like neutralinos, which have been considered previously, we find
detection rates below 1 event per Teraton of target and year in all cases;
often the rates are much smaller. In contrast, if the neutralino is
higgsino--like, more than ten events per year per Teraton might be observed, if
the mass of the $X$ particle is near its lower bound of $\sim 10^{12}$ GeV.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:20:04 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Bornhauser",
"Sascha",
""
],
[
"Drees",
"Manuel",
""
]
] |
0704.3935 | Martin R. Bridson | Martin R Bridson, James Howie, Charles F Miller III, Hamish Short | Subgroups of direct products of limit groups | 20 pages, no figures. Final version. Accepted by the Annals of
Mathematics | null | null | null | math.GR math.GT | null | If $G_1,...,G_n$ are limit groups and $S\subset G_1\times...\times G_n$ is of
type $\FP_n(\mathbb Q)$ then $S$ contains a subgroup of finite index that is
itself a direct product of at most $n$ limit groups. This settles a question of
Sela.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:29:38 GMT"
},
{
"version": "v2",
"created": "Tue, 6 Nov 2007 22:51:24 GMT"
}
] | 2007-11-07T00:00:00 | [
[
"Bridson",
"Martin R",
""
],
[
"Howie",
"James",
""
],
[
"Miller",
"Charles F",
"III"
],
[
"Short",
"Hamish",
""
]
] |
0704.3936 | Leonardo Fernandez-Jambrina | L. Fernandez-Jambrina | Hidden past of dark energy cosmological models | 6 pages, 1 figure, RevTeX4, new references and comments added | Phys.Lett.B656:9-14,2007 | 10.1016/j.physletb.2007.08.091 | null | gr-qc astro-ph hep-th | null | In this paper we analyse the possibility of having homogeneous isotropic
cosmological models with observers reaching $t=\infty$ in finite proper time.
It is shown that just observationally-suggested dark energy models with
$w\in(-5/3,-1)$ show this feature and that they are endowed with an exotic
curvature singularity. Furthermore, it is shown that non-accelerated observers
in these models may experience a duration of the universe as short as desired
by increasing their linear momentum. A subdivision of phantom models in two
families according to this behavior is suggested.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:30:04 GMT"
},
{
"version": "v2",
"created": "Thu, 3 May 2007 10:08:42 GMT"
},
{
"version": "v3",
"created": "Thu, 27 Sep 2007 17:05:12 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Fernandez-Jambrina",
"L.",
""
]
] |
0704.3937 | Athanasios Batakis | Athanasios Batakis, Benoit Testud | Multifractal Analysis of inhomogeneous Bernoulli products | 17 pages | null | null | null | math.MG math.DS | null | We are interested to the multifractal analysis of inhomogeneous Bernoulli
products which are also known as coin tossing measures. We give conditions
ensuring the validity of the multifractal formalism for such measures. On
another hand, we show that these measures can have a dense set of phase
transitions.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:30:27 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Batakis",
"Athanasios",
""
],
[
"Testud",
"Benoit",
""
]
] |
0704.3938 | Kevin J. Resch | K.J. Resch, P. Puvanathasan, J.S. Lundeen, M.W. Mitchell, and K.
Bizheva | Classical dispersion-cancellation interferometry | 4 pages, 3 figures | Optics Express 15, 8797 (2007). | 10.1364/OE.15.008797 | null | quant-ph physics.optics | null | Even-order dispersion cancellation, an effect previously identified with
frequency-entangled photons, is demonstrated experimentally for the first time
with a linear, classical interferometer. A combination of a broad bandwidth
laser and a high resolution spectrometer was used to measure the intensity
correlations between anti-correlated optical frequencies. Only 14% broadening
of the correlation signal is observed when significant material dispersion,
enough to broaden the regular interferogram by 4250%, is introduced into one
arm of the interferometer.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:32:37 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Resch",
"K. J.",
""
],
[
"Puvanathasan",
"P.",
""
],
[
"Lundeen",
"J. S.",
""
],
[
"Mitchell",
"M. W.",
""
],
[
"Bizheva",
"K.",
""
]
] |
0704.3939 | H. W. Braden | H.W. Braden and V.Z. Enolski | Monopoles, Curves and Ramanujan | Rewritten version of math-ph/0601040 | null | null | null | math-ph math.MP | null | We develop the Ercolani-Sinha construction of SU(2) monopoles and make this
effective for (a five parameter family of centred) charge 3 monopoles. In
particular we show how to solve the transcendental constraints arising on the
spectral curve. For a class of symmetric curves the transcendental constraints
become a number theoretic problem and a recently proven identity of Ramanujan
provides a solution.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:33:37 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Braden",
"H. W.",
""
],
[
"Enolski",
"V. Z.",
""
]
] |
0704.3940 | Ryan Budney | Ryan Budney, Alexandra Mozgova | An obstruction to a knot being deform-spun via Alexander polynomials | 6 Pages, 1 Figure. to appear in Proceedings of the AMS | Proc. Amer. Math. Soc. 137 (2009), 3547-3552. | null | null | math.GT | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We show that if a co-dimension two knot is deform-spun from a
lower-dimensional co-dimension 2 knot, there are constraints on the Alexander
polynomials. In particular this shows, for all n, that not all co-dimension 2
knots in S^n are deform-spun from knots in S^{n-1}.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:34:57 GMT"
},
{
"version": "v2",
"created": "Mon, 16 Feb 2009 18:52:46 GMT"
}
] | 2009-08-11T00:00:00 | [
[
"Budney",
"Ryan",
""
],
[
"Mozgova",
"Alexandra",
""
]
] |
0704.3941 | Nicola Menci | A. Cavaliere (1), N. Menci (2) ((1) Dip. Fisica Universita' di Roma
''Tor Vergata'', (2) INAF - Osservatorio Astronomico di Roma) | Bimodal AGNs in Bimodal Galaxies | 7 pages, accepted for publication in the Astrophysical Journal | Astrophys.J.664:47-52,2007 | 10.1086/518879 | Report-no: OAR/07/110 | astro-ph | null | By their star content, the galaxies split out into a red and a blue
population; their color index peaked around u-r=2.5 or u-r=1, respectively,
quantifies the ratio of the blue stars newly formed from cold galactic gas, to
the redder ones left over by past generations. On the other hand, upon
accreting substantial gas amounts the central massive black holes energize
active galactic nuclei (AGNs); here we investigate whether these show a
similar, and possibly related, bimodal partition as for current accretion
activity relative to the past. To this aim we use an updated semianalytic
model; based on Monte Carlo simulations, this follows with a large statistics
the galaxy assemblage, the star generations and the black hole accretions in
the cosmological framework over the redshift span from z=10 to z=0. We test our
simulations for yielding in close detail the observed split of galaxies into a
red, early and a blue, late population. We find that the black hole accretion
activities likewise give rise to two source populations: early, bright quasars
and later, dimmer AGNs. We predict for their Eddington parameter $\lambda_E$ --
the ratio of the current to the past black hole accretions -- a bimodal
distribution; the two branches sit now under $\lambda_E \approx 0.01$ (mainly
contributed by low-luminosity AGNs) and around $\lambda_E \approx 0.3-1$. These
not only mark out the two populations of AGNs, but also will turn out to
correlate strongly with the red or blue color of their host galaxies.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:45:31 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Cavaliere",
"A.",
""
],
[
"Menci",
"N.",
""
]
] |
0704.3942 | Pramod Joag | Ali Saif M. Hassan and Pramod S. Joag | Separability Criterion for multipartite quantum states based on the
Bloch representation of density matrices | 23 pages no figures comments are welcome | Quantum Information and Computation, vol. 8, No. 8&9 (2008)
0773-0790 | null | null | quant-ph | null | We give a new separability criterion, a necessary condition for separability
of $N$-partite quantum states. The criterion is based on the Bloch
representation of a $N$-partite quantum state and makes use of multilinear
algebra, in particular, the matrization of tensors. Our criterion applies to
{\it arbitrary} $N$-partite quantum states in
$\mathcal{H}=\mathcal{H}^{d_1}\otimes \mathcal{H}^{d_2} \otimes ... \otimes
\mathcal{H}^{d_N}.$ The criterion can test whether a $N$-partite state is
entangled and can be applied to different partitions of the $N$-partite system.
We provide examples that show the ability of this criterion to detect
entanglement. We show that this criterion can detect bound entangled states. We
prove a sufficiency condition for separability of a 3-partite state,
straightforwardly generalizable to the case $N > 3,$ under certain condition.
We also give a necessary and sufficient condition for separability of a class
of $N$-qubit states which includes $N$-qubit PPT states.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 13:59:29 GMT"
},
{
"version": "v2",
"created": "Mon, 7 May 2007 15:44:02 GMT"
},
{
"version": "v3",
"created": "Wed, 27 Jun 2007 10:14:22 GMT"
},
{
"version": "v4",
"created": "Mon, 16 Jul 2007 10:44:50 GMT"
},
{
"version": "v5",
"created": "Sun, 13 Apr 2008 13:17:23 GMT"
}
] | 2008-07-17T00:00:00 | [
[
"Hassan",
"Ali Saif M.",
""
],
[
"Joag",
"Pramod S.",
""
]
] |
0704.3943 | Jan Olzem | Jan Olzem | Signatures of SUSY Dark Matter at the LHC and in the Spectra of Cosmic
Rays | PhD thesis, RWTH Aachen 2007, 117 pages, 67 figures; the full
resolution version (9.2M pdf) is available from
http://darwin.bth.rwth-aachen.de/opus3/volltexte/2007/1842/pdf/Olzem_Jan.pdf | null | null | null | astro-ph | null | This thesis discusses the search for supersymmetry at the future Large Hadron
Collider (LHC) and the ongoing construction of one of the four large LHC
experiments, the Compact Muon Solenoid (CMS), and focuses on the detection of
signals from the annihilation of supersymmetric dark matter in the spectra of
cosmic rays.
Measurements of cosmic ray antiparticles, such as positrons, can impose
strong constraints on the nature of new physics beyond the Standard Model.
However, cosmic ray positron measurements are experimentally very challenging
due to the vast proton background. A novel approach of positron identification
with the space-borne AMS-01 experiment, namely through the detection of
bremsstrahlung conversion in a silicon microstrip detector, is introduced.
Bremsstrahlung from protons is suppressed by a factor of more than 3*10^6 with
respect to positrons. The results of the positron measurement show that the
bremsstrahlung approach extends the sensitivity range of AMS-01 to positron
momenta up to 50 GeV/c, which is far beyond the original scope of the
experiment. At momenta above 8 GeV/c there is indication for a positron
overabundance with respect to model predictions for purely secondary positron
production. Therefore, the AMS-01 data lend further weight to the hints of a
positron overabundance seen in the data from earlier experiments.
The positron fraction measurements from the most recent experiments are
combined with the results of this analysis, giving the most precise positron
fraction data yet available.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:02:34 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Olzem",
"Jan",
""
]
] |
0704.3944 | Lars Fuhrmann | L. Fuhrmann, J. A. Zensus, T. P. Krichbaum, E. Angelakis, A. C. S.
Readhead | Simultaneous Radio to (Sub-) mm-Monitoring of Variability and Spectral
Shape Evolution of potential GLAST Blazars | 3 pages, to appear in the Proceedings of the First GLAST Symposium,
Stanford University, February 2007 | AIP Conf.Proc.921:249-251,2007 | 10.1063/1.2757314 | null | astro-ph | null | The Large Area Telescope (LAT) instrument onboard GLAST offers a tremendous
opportunity for future blazar studies. In order to fully benefit from its
capabilities and to maximize the scientific return from the LAT, it is of great
importance to conduct dedicated multi-frequency monitoring campaigns that will
result comprehensive observations. Consequently, we initiated an effort to
conduct a GLAST-dedicated, quasi-simultaneous, broad-band flux-density (and
polarization) monitoring of potential GLAST blazars with the Effelsberg and
OVRO radio telescopes (11cm to 7mm wavelength). Here, we present a short
overview of these activities which will complement the multi-wavelengths
activities of the GLAST/LAT collaboration towards the 'low-energy' radio bands.
Further we will give a brief outlook including the extension of this
coordinated campaign towards higher frequencies and future scientific aims.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:09:36 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Fuhrmann",
"L.",
""
],
[
"Zensus",
"J. A.",
""
],
[
"Krichbaum",
"T. P.",
""
],
[
"Angelakis",
"E.",
""
],
[
"Readhead",
"A. C. S.",
""
]
] |
0704.3945 | Jean-Baptiste Masson | Jean-Baptiste Masson (LOB), Guilhem Gallot (LOB) | Extra energy coupling through subwavelength hole arrays via stochastic
resonance | 12 pages | null | null | null | cond-mat.other physics.optics | null | Interaction between metal surface waves and periodic geometry of
subwavelength structures is at the core of the recent but crucial renewal of
interest in plasmonics. One of the most intriguing points is the observation of
abnormal strong transmission through these periodic structures, which can
exceed by orders of magnitude the classical transmission given by the filling
factor of the plate. The actual paradigm is that this abnormal transmission
arises from the periodicity, and then that such high transmission should
disappear in random geometries. Here, we show that extra energy can be coupled
through the subwavelength structure by adding a controlled quantity of noise to
the position of the apertures. This result can be modelled in the statistical
framework of stochastic resonance. The evolution of the coupled energy with
respect to noise gives access to the extra energy coupled at the surface of the
subwavelength array.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:17:51 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Masson",
"Jean-Baptiste",
"",
"LOB"
],
[
"Gallot",
"Guilhem",
"",
"LOB"
]
] |
0704.3946 | Harald Kittang | Bj{\o}rn Ian Dundas and Harald {\O}yen Kittang | Excision for K-theory of connective ring spectra | 11 pages | null | null | null | math.KT | null | We extend Geisser and Hesselholt's result on ``bi-relative K-theory'' from
discrete rings to connective ring spectra. That is, if $\mathcal A$ is a
homotopy cartesian $n$-cube of ring spectra (satisfying connectivity
hypotheses), then the $(n+1)$-cube induced by the cyclotomic trace $$K(\mathcal
A)\to TC(\mathcal A)$$ is homotopy cartesian after profinite completion. In
other words, the fiber of the profinitely completed cyclotomic trace satisfies
excision.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:20:56 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Dundas",
"Bjørn Ian",
""
],
[
"Kittang",
"Harald Øyen",
""
]
] |
0704.3947 | Ross Springell | R Springell, S W Zochowski, R C C Ward, M R Wells, S D Brown, L
Bouchenoire, F Wilhelm, S Langridge, W G Stirling and G H Lander | A study of uranium-based multilayers: I. Fabrication and structural
characterisation | 18 pages, 7 figures, submitted to J. Phys.: Condens. Matter | null | null | null | cond-mat.mtrl-sci cond-mat.other | null | This paper addresses the structural characterisation of a series of U/Fe,
U/Co and U/Gd multilayers. X-ray reflectivity has been employed to investigate
the layer thickness and roughness parameters along the growth direction and
high-angle diffraction measurements have been used to determine the crystal
structure and orientation of the layers. For the case of uranium/transition
metal systems, the interfaces are diffuse and the transition metals are present
in a polycrystalline form of their common bulk phases with a preferred
orientation along the closest packed planes; Fe, bcc (110) and Co, hcp (001),
respectively. The uranium is present in a poorly crystalline orthorhombic,
alpha-U state. In contrast, the U/Gd multilayers have sharp interfaces with
negligible intermixing of atomic species, and have a roughness, which is
strongly dependent on the gadolinium layer thickness. Diffraction spectra
indicate a high degree of crystallinity in both U and Gd layers with
intensities consistent with the growth of a novel hcp U phase, stabilised by
the hcp gadolinium layers.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:23:22 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Springell",
"R",
""
],
[
"Zochowski",
"S W",
""
],
[
"Ward",
"R C C",
""
],
[
"Wells",
"M R",
""
],
[
"Brown",
"S D",
""
],
[
"Bouchenoire",
"L",
""
],
[
"Wilhelm",
"F",
""
],
[
"Langridge",
"S",
""
],
[
"Stirling",
"W G",
""
],
[
"Lander",
"G H",
""
]
] |
0704.3948 | Alexey Mazur K | Alexey K. Mazur | The Worm-Like Chain Theory And Bending Of Short DNA | 4 pages, 3 figures, to appear in PRL | Phys. Rev. Lett. 98, 218102, 2007. | 10.1103/PhysRevLett.98.218102 | null | q-bio.BM cond-mat.soft physics.bio-ph | null | The probability distributions for bending angles in double helical DNA
obtained in all-atom molecular dynamics simulations are compared with
theoretical predictions. The computed distributions remarkably agree with the
worm-like chain theory for double helices of one helical turn and longer, and
qualitatively differ from predictions of the semi-elastic chain model. The
computed data exhibit only small anomalies in the apparent flexibility of short
DNA and cannot account for the recently reported AFM data (Wiggins et al,
Nature nanotechnology 1, 137 (2006)). It is possible that the current atomistic
DNA models miss some essential mechanisms of DNA bending on intermediate length
scales. Analysis of bent DNA structures reveals, however, that the bending
motion is structurally heterogeneous and directionally anisotropic on the
intermediate length scales where the experimental anomalies were detected.
These effects are essential for interpretation of the experimental data and
they also can be responsible for the apparent discrepancy.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:24:59 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Mazur",
"Alexey K.",
""
]
] |
0704.3949 | Ian Appelbaum | Biqin Huang (1), Lai Zhao (1), Douwe J. Monsma (2), Ian Appelbaum (1)
((1) University of Delaware, (2) Cambridge NanoTech Inc.) | 35% magnetocurrent with spin transport through Si | null | Appl. Phys. Lett. 91, 052501 (2007) | 10.1063/1.2767198 | null | cond-mat.mtrl-sci cond-mat.other | null | Efficient injection of spin-polarized electrons into the conduction band of
silicon is limited by the formation of a silicide at the ferromagnetic metal
(FM)/silicon interface. In the present work, this "magnetically-dead" silicide
(where strong spin-scattering significantly reduces injected spin polarization)
is eliminated by moving the FM in the spin injector from the tunnel junction
base anode to the emitter cathode and away from the silicon surface. This
results in over an order-of-magnitude increase in spin injection efficiency,
from a previously-reported magnetocurrent ratio of ~2% to ~35% and an estimated
spin polarization in Si from ~1% to at least ~15%. The injector tunnel-junction
bias dependence of this spin transport signal is also measured, demonstrating
the importance of low bias voltage to preserve high injected spin polarization.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:31:01 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Huang",
"Biqin",
"",
"University of Delaware"
],
[
"Zhao",
"Lai",
"",
"University of Delaware"
],
[
"Monsma",
"Douwe J.",
"",
"Cambridge NanoTech Inc"
],
[
"Appelbaum",
"Ian",
"",
"University of Delaware"
]
] |
0704.3950 | Mu-Lin Yan | Wei Huang, Wang Xu, Mu-Lin Yan | Backward Compton Scattering and QED with Noncommutative Plane in the
Strong Uniform Magnetic Field | 13 pages, 5 figures | Chinese Physics C 2008 32 (05): 342-347 | 10.1088/1674-1137/32/5/003 | USTC-ICTS-07-08 | hep-ph cond-mat.mes-hall | null | In the strong uniform magnetic field, the noncommutative plane (NCP) caused
by the lowest Landau level (LLL) effect, and QED with NCP (QED-NCP) are
studied. Being similar to the condensed matter theory of quantum Hall effect,
an effective filling factor $f(B)$ is introduced to character the possibility
that the electrons stay on the LLL. The analytic and numerical results of the
differential cross section for the process of backward Compton scattering in
the accelerator with unpolarized or polarized initial photons are calculated.
The existing data of BL38B2 in Spring-8 have been analyzed roughly and compared
with the numerical predictions primitively. We propose a precise measurement of
the differential cross sections of backward Compton scattering in a strong
perpendicular magnetic field, which may lead to reveal the effects of QED-NCP.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:34:09 GMT"
},
{
"version": "v2",
"created": "Wed, 14 May 2008 15:41:44 GMT"
}
] | 2012-05-22T00:00:00 | [
[
"Huang",
"Wei",
""
],
[
"Xu",
"Wang",
""
],
[
"Yan",
"Mu-Lin",
""
]
] |
0704.3951 | G. Griffith Elder | Nigel P. Byott and G. Griffith Elder | On the necessity of new ramification breaks | null | null | null | null | math.NT | null | Ramification invariants are necessary, but not in general sufficient, to
determine the Galois module structure of ideals in local number field
extensions. This insufficiency is associated with elementary abelian
extensions, where one can define a refined ramification filtration -- one with
more ramification breaks [JNTB 17 (2005)]. The first refined break number comes
from the usual ramification filtration and is therefore necessary. Here we
study the second refined break number.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:36:16 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Byott",
"Nigel P.",
""
],
[
"Elder",
"G. Griffith",
""
]
] |
0704.3952 | Peter Grabner | Gregory Derfel, Peter J. Grabner, Fritz Vogl | Complex asymptotics of Poincar\'e functions and properties of Julia sets | Final version accepted for publication in Math. Proc. Camb. Philos.
Soc | Mathematical Proceedings of the Cambridge Philosophical Society
2008 | 10.1017/S0305004108001564 | null | math.CV math.DS | null | The asymptotic behaviour of the solutions of Poincar\'e's functional equation
$f(\lambda z)=p(f(z))$ ($\lambda>1$) for $p$ a real polynomial of degree
$\geq2$ is studied in angular regions of the complex plain. The constancy of
an occurring periodic function is characterised in terms of geometric
properties of the Julia set of $p$. For real Julia sets we give inequalities
for multipliers of Pommerenke-Levin-Yoccoz type. The distribution of zeros of
$f$ is related to the harmonic measure on the Julia set of $p$.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:41:57 GMT"
},
{
"version": "v2",
"created": "Fri, 23 Nov 2007 10:09:08 GMT"
}
] | 2020-07-27T00:00:00 | [
[
"Derfel",
"Gregory",
""
],
[
"Grabner",
"Peter J.",
""
],
[
"Vogl",
"Fritz",
""
]
] |
0704.3953 | Pierre-Henri Chavanis | P.H. Chavanis | Kinetic theory of two dimensional point vortices from a BBGKY-like
hierarchy | null | Physica A, 387, 1123 (2008) | 10.1016/j.physa.2007.10.022 | null | cond-mat.stat-mech | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Starting from the Liouville equation, we derive the exact hierarchy of
equations satisfied by the reduced distribution functions of the single species
point vortex gas in two dimensions. Considering an expansion of the solution in
powers of 1/N in a proper thermodynamic limit $N\to +\infty$, and neglecting
some collective effects, we derive a kinetic equation satisfied by the smooth
vorticity field which is valid at order $O(1/N)$. This equation was obtained
previously [P.H. Chavanis, Phys. Rev. E, 64, 026309 (2001)] from a more
abstract projection operator formalism. If we consider axisymmetric flows and
make a markovian approximation, we obtain a simpler kinetic equation which can
be studied in great detail. We discuss the properties of these kinetic
equations in regard to the $H$-theorem and the convergence (or not) towards the
statistical equilibrium state. We also study the growth of correlations by
explicitly calculating the time evolution of the two-body correlation function
in the linear regime. In a second part of the paper, we consider the relaxation
of a test vortex in a bath of field vortices and obtain the Fokker-Planck
equation by directly calculating the second (diffusion) and first (drift)
moments of the increment of position of the test vortex. A specificity of our
approach is to obtain general equations, with a clear physical meaning, that
are valid for flows that are not necessarily axisymmetric and that take into
account non-Markovian effects. A limitations of our approach, however, is that
it ignores collective effects.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:45:03 GMT"
},
{
"version": "v2",
"created": "Thu, 19 Jun 2008 08:53:17 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Chavanis",
"P. H.",
""
]
] |
0704.3954 | Pamela Morehouse | G. Bonvicini, et al, CLEO Collaboration | Dalitz Plot Analysis of the D+ --> pi- pi+ pi+ Decay | 31 pages postscript,also available through
http://www.lns.cornell.edu/public/CLNS/2007/ | Phys.Rev.D76:012001,2007 | 10.1103/PhysRevD.76.012001 | CLNS 07/1993, CLEO 07-3 | hep-ex | null | Using 281 pb^{-1} of data recorded by the CLEO-c detector in e^+e^-
collisions at the psi(3770), corresponding to 0.78 million D^+D^- pairs, we
investigate the substructure of the decay D^+ to pi^- pi^+ pi^+ using the
Dalitz plot technique. We find that our data are consistent with the following
intermediate states: rho(770)pi^+, f_2(1270)pi^+, f_0(1370)pi^+, f_0(1500)pi^+,
f_0(980) pi^+, and sigma pi^+. We confirm large S wave contributions at low pi
pi mass. We set upper limits on contributions of other possible intermediate
states. We consider three models of the pi pi S wave and find that all of them
adequately describe our data.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:57:30 GMT"
},
{
"version": "v2",
"created": "Thu, 5 Jul 2007 13:12:26 GMT"
}
] | 2010-04-08T00:00:00 | [
[
"Bonvicini",
"G.",
""
],
[
"Collaboration",
"CLEO",
""
]
] |
0704.3955 | Claude Dion | P. Sjolund, S. J. H. Petra, C. M. Dion, H. Hagman, S. Jonsell, and A.
Kastberg | Characterisation of a three-dimensional Brownian motor in optical
lattices | 8 pages, 14 figures | Eur. Phys. J. D 44, 381 (2007) | 10.1140/epjd/e2007-00233-3 | null | physics.atom-ph | null | We present here a detailed study of the behaviour of a three dimensional
Brownian motor based on cold atoms in a double optical lattice [P. Sjolund et
al., Phys. Rev. Lett. 96, 190602 (2006)]. This includes both experiments and
numerical simulations of a Brownian particle. The potentials used are spatially
and temporally symmetric, but combined spatiotemporal symmetry is broken by
phase shifts and asymmetric transfer rates between potentials. The diffusion of
atoms in the optical lattices is rectified and controlled both in direction and
speed along three dimensions. We explore a large range of experimental
parameters, where irradiances and detunings of the optical lattice lights are
varied within the dissipative regime. Induced drift velocities in the order of
one atomic recoil velocity have been achieved.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 14:58:08 GMT"
}
] | 2007-09-18T00:00:00 | [
[
"Sjolund",
"P.",
""
],
[
"Petra",
"S. J. H.",
""
],
[
"Dion",
"C. M.",
""
],
[
"Hagman",
"H.",
""
],
[
"Jonsell",
"S.",
""
],
[
"Kastberg",
"A.",
""
]
] |
0704.3956 | Gordon Petrie | G.J.D. Petrie, J.W.S. Blokland and R. Keppens | Magnetohydrostatic solar prominences in near-potential coronal magnetic
fields | To appear in ApJ August 2007 | Astrophys.J.665:830-845,2007 | 10.1086/519276 | null | astro-ph | null | We present numerical magnetohydrostatic solutions describing the
gravitationally stratified, bulk equilibrium of cool, dense prominence plasma
embedded in a near-potential coronal field. These solutions are calculated
using the FINESSE magnetohydrodynamics equilibrium solver and describe the
morphologies of magnetic field distributions in and around prominences and the
cool prominence plasma that these fields support. The equilibrium condition for
this class of problem is usually different in distinct subdomains, separated by
free boundaries, across which solutions are matched by suitable continuity or
jump conditions describing force balance. We employ our precise finite element
elliptic solver to calculate solutions not accessible by previous analytical
techniques with temperature or entropy prescribed as free functions of the
magnetic flux function, including a range of values of the polytropic index,
temperature variations mainly across magnetic field lines and photospheric
field profiles sheared close to the polarity inversion line. Out of the many
examples computed here, perhaps the most noteworthy is one which reproduces
precisely the three-part structure often encountered in observations: a cool
dense prominence within a cavity/flux rope embedded in a hot corona. The
stability properties of these new equilibria, which may be relevant to solar
eruptions, can be determined in the form of a full resistive MHD spectrum using
a companion hyperbolic stability solver.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 15:00:03 GMT"
}
] | 2019-08-19T00:00:00 | [
[
"Petrie",
"G. J. D.",
""
],
[
"Blokland",
"J. W. S.",
""
],
[
"Keppens",
"R.",
""
]
] |
0704.3957 | Vasily Ogryzko V | Vasily Ogryzko | Erwin Schroedinger, Francis Crick and epigenetic stability | New and improved version of the essay, now published in the online
journal 'Biology Direct'. Contains more expanded discussion on entanglement.
18 pages, 2 figures. The file includes open reviews by E.Koonin, V.Vedral and
E.Karsenti | Biol Direct. 2008 Apr 17;3(1):15 | null | null | physics.gen-ph q-bio.MN | null | Schroedinger's book 'What is Life?' is widely credited for having played a
crucial role in development of molecular and cellular biology. My essay
revisits the issues raised by this book from the modern perspective of
epigenetics and systems biology. I contrast two classes of potential mechanisms
of epigenetic stability: 'epigenetic templating' and 'systems biology'
approaches, and consider them from the point of view expressed by Schroedinger.
I also discuss how quantum entanglement, a nonclassical feature of quantum
mechanics, can help to address the 'problem of small numbers' that lead
Schroedinger to promote the idea of molecular code-script for explanation of
stability of biological order.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 17:35:02 GMT"
},
{
"version": "v2",
"created": "Wed, 28 May 2008 12:16:59 GMT"
}
] | 2008-05-30T00:00:00 | [
[
"Ogryzko",
"Vasily",
""
]
] |
0704.3958 | Brian Rodriguez | Sergei V. Kalinin, Brian J. Rodriguez, Stephen Jesse, Katyayani Seal,
Roger Proksch, Sophia Hohlbauch, Irene Revenko, Gary Lee Thompson, Alexey A.
Vertegel | Towards local electromechanical probing of cellular and biomolecular
systems in a liquid environment | 37 pages (including refs), 8 figures | 2007 Nanotechnology 18 424020 (10pp) | 10.1088/0957-4484/18/42/424020 | null | cond-mat.other cond-mat.soft | null | Electromechanical coupling is ubiquitous in biological systems with examples
ranging from simple piezoelectricity in calcified and connective tissues to
voltage-gated ion channels, energy storage in mitochondria, and
electromechanical activity in cardiac myocytes and outer hair cell stereocilia.
Piezoresponse force microscopy (PFM) has originally emerged as a technique to
study electromechanical phenomena in ferroelectric materials, and in recent
years, has been employed to study a broad range of non-ferroelectric polar
materials, including piezoelectric biomaterials. At the same time, the
technique has been extended from ambient to liquid imaging on model
ferroelectric systems. Here, we present results on local electromechanical
probing of several model cellular and biomolecular systems, including insulin
and lysozyme amyloid fibrils, breast adenocarcinoma cells, and
bacteriorhodopsin in a liquid environment. The specific features of SPM
operation in liquid are delineated and bottlenecks on the route towards
nanometer-resolution electromechanical imaging of biological systems are
identified.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 15:20:18 GMT"
}
] | 2008-03-13T00:00:00 | [
[
"Kalinin",
"Sergei V.",
""
],
[
"Rodriguez",
"Brian J.",
""
],
[
"Jesse",
"Stephen",
""
],
[
"Seal",
"Katyayani",
""
],
[
"Proksch",
"Roger",
""
],
[
"Hohlbauch",
"Sophia",
""
],
[
"Revenko",
"Irene",
""
],
[
"Thompson",
"Gary Lee",
""
],
[
"Vertegel",
"Alexey A.",
""
]
] |
0704.3959 | Eric Charron | Naceur Gaaloul (PPM, LSAMA), Amine Jaouadi (PPM, LSAMA), Mourad
Telmini (LSAMA), Laurence Pruvost (LAC), Eric Charron (PPM) | Optical Devices for Cold Atoms and Bose-Einstein Condensates | Proceedings of the International Spectroscopy Conference ISC-2007,
Sousse, Tunisia | AIP Conference Proceedings 935 (2007) 10 | 10.1063/1.2795399 | null | quant-ph | null | The manipulation of cold atoms with optical fields is a very promising
technique for a variety of applications ranging from laser cooling and trapping
to coherent atom transport and matter wave interferometry. Optical fields have
also been proposed as interesting tools for quantum information processing with
cold atoms. In this paper, we present a theoretical study of the dynamics of a
cold 87Rb atomic cloud falling in the gravity field in the presence of two
crossing dipole guides. The cloud is either deflected or split between the two
branches of this guide. We explore the possibilities of optimization of this
device and present preliminary results obtained in the case of zero-temperature
dilute Bose-Einstein condensates.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 15:16:47 GMT"
},
{
"version": "v2",
"created": "Mon, 11 Jun 2007 15:33:06 GMT"
}
] | 2007-09-24T00:00:00 | [
[
"Gaaloul",
"Naceur",
"",
"PPM, LSAMA"
],
[
"Jaouadi",
"Amine",
"",
"PPM, LSAMA"
],
[
"Telmini",
"Mourad",
"",
"LSAMA"
],
[
"Pruvost",
"Laurence",
"",
"LAC"
],
[
"Charron",
"Eric",
"",
"PPM"
]
] |
0704.3960 | Justyn Maund | J. Craig Wheeler, Justyn R. Maund and Shizuka Akiyama | Supernova Asymmetries | 8 pages, 3 figures, to be published in the proceedings of the
conference "Supernova 1987A: 20 Years After" Aspen, 2007 | AIP Conf.Proc.937:349-356,2007 | 10.1063/1.2803590 | null | astro-ph | null | All core collapse supernovae are strongly aspherical. The "Bochum event,"
with velocity components displaced symmetrically about the principal H$\alpha$
line, strongly suggests that SN 1987A was a bi-polar rather than a uni-polar
explosion. While there is a general tendency to display a single prominant axis
in images and spectropolarimetry, there is also growing evidence for frequent
departures from axisymmetry. There are various mechanisms that might contribute
to large scale departures from spherical symmetry: jet-induced processes, the
spherical shock accretion instability (SASI) and associated phenomena, and
non-axisymmetric instabilities (NAXI). The MRI gives inevitable production of
large toroidal magnetic fields. In sum: no $\Omega$ without B. The role of
magnetic fields, non-axisymmetric instabilities, and of the de-leptonization
phase are discussed.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 15:19:17 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Wheeler",
"J. Craig",
""
],
[
"Maund",
"Justyn R.",
""
],
[
"Akiyama",
"Shizuka",
""
]
] |
0704.3961 | Pablo Arrighi | Pablo Arrighi, Renan Fargetton, Zizhu Wang | Intrinsically universal one-dimensional quantum cellular automata in two
flavours | 27 pages, revtex, 23 figures. V3: The results of V1-V2 are better
explained and formalized, and a novel result about intrinsic universality
with only finite initial configurations is given | V1-V2: DCM 2007, Poland. V3: Fudam. Informaticae journal | null | null | quant-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We give a one-dimensional quantum cellular automaton (QCA) capable of
simulating all others. By this we mean that the initial configuration and the
local transition rule of any one-dimensional QCA can be encoded within the
initial configuration of the universal QCA. Several steps of the universal QCA
will then correspond to one step of the simulated QCA. The simulation preserves
the topology in the sense that each cell of the simulated QCA is encoded as a
group of adjacent cells in the universal QCA. The encoding is linear and hence
does not carry any of the cost of the computation. We do this in two flavours:
a weak one which requires an infinite but periodic initial configuration and a
strong one which needs only a finite initial configuration. KEYWORDS: Quantum
cellular automata, Intrinsic universality, Quantum computation.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 15:22:05 GMT"
},
{
"version": "v2",
"created": "Tue, 1 May 2007 14:50:57 GMT"
},
{
"version": "v3",
"created": "Wed, 10 Dec 2008 15:09:29 GMT"
}
] | 2008-12-10T00:00:00 | [
[
"Arrighi",
"Pablo",
""
],
[
"Fargetton",
"Renan",
""
],
[
"Wang",
"Zizhu",
""
]
] |
0704.3962 | Christine Noot-Huyghe | Christine Noot-Huyghe (IRMA) | Un th\'eor\`eme de Beilinson-Bernstein pour les D-modules
arithm\'etiques | 22 pages; Preprint (29/04/2007) | null | null | null | math.AG | null | One proves a Beilinson-Bernstein theorem in the context of arithmetic
D-modules introduced by Berthelot, for flag varieties. This generalizes in the
arithmetic context previous results of Brylinski-Kashiwara and
Beilinson-Bernstein in the complex case.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 15:29:18 GMT"
},
{
"version": "v2",
"created": "Fri, 25 May 2007 12:04:45 GMT"
}
] | 2007-06-13T00:00:00 | [
[
"Noot-Huyghe",
"Christine",
"",
"IRMA"
]
] |
0704.3963 | Andreas Mueller | Andreas Mueller and Bernd Aschenbach | Non-monotonic orbital velocity profiles around rapidly rotating
Kerr-(anti-)de Sitter black holes | 9 pages, 4 figures, accepted for Class. Quant. Grav | Class.Quant.Grav.24:2637-2644,2007 | 10.1088/0264-9381/24/10/009 | null | gr-qc astro-ph | null | It has been recently demonstrated that the orbital velocity profile around
Kerr black holes in the equatorial plane as observed in the locally
non-rotating frame exhibits a non-monotonic radial behaviour. We show here that
this unexpected minimum-maximum feature of the orbital velocity remains if the
Kerr vacuum is generalized to the Kerr-de Sitter or Kerr-anti-de Sitter metric.
This is a new general relativity effect in Kerr spacetimes with non-vanishing
cosmological constant. Assuming that the profile of the orbital velocity is
known, this effect constrains the spacetime parameters.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 15:32:14 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Mueller",
"Andreas",
""
],
[
"Aschenbach",
"Bernd",
""
]
] |
0704.3964 | Fernando Martinez-Vidal | F. Martinez-Vidal (On behalf of the BaBar Collaboration) | Measurement of the CKM angle gammma with B-+ ->D^(*)[K0s pi- pi+]K^(*)-+
decays in BaBar | Proceedings of the 4th International Workshop on the CKM Unitarity
Triangle (CKM'06), 12-16 December, 2006, Nagoya (Japan) | null | null | null | hep-ex | null | We report on the measurement of the Cabibbo-Kobayashi-Maskawa angle gamma
through a Dalitz analysis of neutral D decays to K0s pi- pi+ in the processes
B-+ -> D^(*) K-+ and B-+ -> D K^*-+, D^* -> D pi0, D gamma, with the Babar
detector at the SLAC PEP-II e^+ e^- asymmetric-energy collider.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 15:59:02 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Martinez-Vidal",
"F.",
"",
"On behalf of the BaBar Collaboration"
]
] |
0704.3965 | Servio Perez | S.T. Perez-Merchancano, G. E. Marques, and L.E. Bolivar-Marinez | Optical Transitions in New Trends Organic Materials | 4 pages, 5 figures, references. Submitted to the Microelectronic
Journal | null | null | null | cond-mat.other | null | The PTCDA (3,4,9,10-Perylene-tetracarboxylic dianhydride) and the NTCDA
(1,4,5,8-Naphtalenetetracarboxylic dianhydride) are aromatic, stable, planar
and highly symmetric with unusual electrical properties. The PTCDA is a
semiconductor organic crystalline of particular interest due to its excellent
properties and electronic potential that are used in optoelectronic devices and
the NTCDA it is monoclinic and its space group is similar to that of the PTCDA.
Recently, alternate layers of PTCDA and NTCDA were growth forming multiple
structures of quantum wells showing a new class of materials with new optic
lineal properties. Some have assured that their big utilities would be centered
in the construction of diodes and of possible guides of waves. We have carried
out calculations semi-empirical of the electronic structures and of optic
properties of the PTCDA and of the NTCDA that show us that they are structures
highly orderly polymeric, semiconductors in a negative load state (charge
state= -2)
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 16:29:41 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Perez-Merchancano",
"S. T.",
""
],
[
"Marques",
"G. E.",
""
],
[
"Bolivar-Marinez",
"L. E.",
""
]
] |
0704.3966 | Gary Goldstein | Gary R. Goldstein | Dick Dalitz: Examples of His Contributions to Particle Physics | 14 pages, 9 figures, for Proceedings ISSP Erice 2006 | null | 10.1142/9789812832467_0017 | null | physics.hist-ph hep-ph nucl-th | null | Dick Dalitz produced lasting contributions to particle physics for 50 years.
Along with Dalitz pairs, Dalitz plots and CDD poles, he did major work in
parity violation, hyperon resonance identification, the quark model, and
hypernuclei. These topics will be summarized, with some emphasis on the
author's collaboration with Dalitz on quark spin and fragmentation
correlations, and, particularly, the work on the identification of the top
quark and its mass. Short biographical information is interspersed. This paper
is based on a presentation at the International School of Subnuclear Physics,
Erice 2006.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 16:02:16 GMT"
}
] | 2017-08-23T00:00:00 | [
[
"Goldstein",
"Gary R.",
""
]
] |
0704.3967 | Michael Potthoff | A. Fleszar, M. Potthoff, W. Hanke | Electronic structure of zinc-blende MnTe within the GW approximation | 9 pages, accepted for publication in pssc (special issue on II-VI
semiconductors) | null | 10.1002/pssc.200775407 | null | cond-mat.str-el | null | Using the local spin-density approximation (LSDA) and the (non
self-consistent) GW approach, the (quasi-particle) band structure is calculated
for MnTe in zinc-blende geometry. Different parameters characterizing the
electronic structure are computed for an antiferromagnetic and the
ferromagnetic phase and compared with the experiment. The strong Hubbard-type
repulsion on the Mn-3d orbitals and the p-d hybridization are seen to be
responsible for substantial defects found in the LSDA picture. It is discussed
to which extent these can be improved upon by means of the GW approach.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 16:20:27 GMT"
}
] | 2015-05-13T00:00:00 | [
[
"Fleszar",
"A.",
""
],
[
"Potthoff",
"M.",
""
],
[
"Hanke",
"W.",
""
]
] |
0704.3968 | Andrzej Czarnecki | A. Czarnecki, W. J. Marciano, and A. Sirlin | Electroweak Radiative Corrections to Muon Capture | 6 pages | Phys.Rev.Lett.99:032003,2007 | 10.1103/PhysRevLett.99.032003 | null | hep-ph | null | Electroweak radiative corrections to muon capture on nuclei are computed and
found to be sizable. They enhance the capture rates for hydrogen and helium by
2.8% and 3.0% respectively. As a result, the value of the induced pseudoscalar
coupling, g_P^exp, extracted from a recent hydrogen 1S singlet capture
experiment is increased by about 21% to g_P^exp = 7.3 +/- 1.2 and brought into
good agreement with the prediction of chiral perturbation theory,
g_P^theory=8.2 +/- 0.2. Implications for helium capture rate predictions are
also discussed.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 16:25:46 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Czarnecki",
"A.",
""
],
[
"Marciano",
"W. J.",
""
],
[
"Sirlin",
"A.",
""
]
] |
0704.3969 | Jean-Claude Belfiore | Sheng Yang and Jean-Claude Belfiore | Diversity of MIMO Multihop Relay Channels - Part I: Amplify-and-Forward | 37 pages, 15 figures. submitted to IEEE Transactions on Information
Theory | null | null | null | cs.IT math.IT | null | In this two-part paper, we consider the multiantenna multihop relay channels
in which the source signal arrives at the destination through N independent
relaying hops in series. The main concern of this work is to design relaying
strategies that utilize efficiently the relays in such a way that the diversity
is maximized. In part I, we focus on the amplify-and-forward (AF) strategy with
which the relays simply scale the received signal and retransmit it. More
specifically, we characterize the diversity-multiplexing tradeoff (DMT) of the
AF scheme in a general multihop channel with arbitrary number of antennas and
arbitrary number of hops. The DMT is in closed-form expression as a function of
the number of antennas at each node. First, we provide some basic results on
the DMT of the general Rayleigh product channels. It turns out that these
results have very simple and intuitive interpretation. Then, the results are
applied to the AF multihop channels which is shown to be equivalent to the
Rayleigh product channel, in the DMT sense. Finally, the project-and-forward
(PF) scheme, a variant of the AF scheme, is proposed. We show that the PF
scheme has the same DMT as the AF scheme, while the PF can have significant
power gain over the AF scheme in some cases. In part II, we will derive the
upper bound on the diversity of the multihop channels and show that it can be
achieved by partitioning the multihop channel into AF subchannels.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 16:28:51 GMT"
}
] | 2007-07-13T00:00:00 | [
[
"Yang",
"Sheng",
""
],
[
"Belfiore",
"Jean-Claude",
""
]
] |
0704.3970 | Ross Springell | R Springell, S W Zochowski, R C C Ward, M R Wells, S D Brown, L
Bouchenoire, F Wilhelm, S Langridge, W G Stirling and G H Lander | A study of uranium-based multilayers: II. Magnetic properties | 18 pages, 8 figures, submitted to J. Phys.: Condens. Matter | null | 10.1088/0953-8984/20/21/215230 | null | cond-mat.mtrl-sci cond-mat.other | null | SQUID magnetometry and polarised neutron reflectivity measurements have been
employed to characterise the magnetic properties of U/Fe, U/Co and U/Gd
multilayers. The field dependence of the magnetisation was measured at 10K in
magnetic fields from -70kOe to 70kOe. A temperature dependent study of the
magnetisation evolution was undertaken for a selection of U/Gd samples. PNR was
carried out in a field of 4.4kOe for U/Fe and U/Co samples (at room
temperature) and for U/Gd samples (at 10K). Magnetic 'dead' layers of about 15
Angstrom were observed for U/Fe and U/Co samples, consistent with a picture of
interdiffused interfaces. A large reduction in the magnetic moment, constant
over a wide range of Gd layer thicknesses, was found for the U/Gd system (about
4 Bohr magnetons compared with 7.63 for the bulk metal). This could be
understood on the basis of a pinning of Gd moments arising from a column-like
growth mechanism of the Gd layers. A study of the effective anisotropy suggests
that perpendicular magnetic anisotropy could occur in multilayers consisting of
thick U and thin Gd layers. A reduction in the Curie temperature was observed
as a function of Gd layer thickness, consistent with a finite-size scaling
behaviour.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 16:51:44 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Springell",
"R",
""
],
[
"Zochowski",
"S W",
""
],
[
"Ward",
"R C C",
""
],
[
"Wells",
"M R",
""
],
[
"Brown",
"S D",
""
],
[
"Bouchenoire",
"L",
""
],
[
"Wilhelm",
"F",
""
],
[
"Langridge",
"S",
""
],
[
"Stirling",
"W G",
""
],
[
"Lander",
"G H",
""
]
] |
0704.3971 | Tobias Kipp | Ch. Strelow, C. M. Schultz, H. Rehberg, H. Welsch, Ch. Heyn, D.
Heitmann and T. Kipp | Three-Dimensionally Confined Optical Modes in Quantum Well Microtube
Ring Resonators | 5 pages, 4 figures | null | 10.1103/PhysRevB.76.045303 | null | cond-mat.other | null | We report on microtube ring resonators with quantum wells embedded as an
optically active material. Optical modes are observed over a broad energy
range. Their properties strongly depend on the exact geometry of the microtube
along its axis. In particular we observe (i) preferential emission of light on
the inside edge of the microtube and (ii) confinement of light also in
direction of the tube axis by an axially varying geometry which is explained in
an expanded waveguide model.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 16:31:31 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Strelow",
"Ch.",
""
],
[
"Schultz",
"C. M.",
""
],
[
"Rehberg",
"H.",
""
],
[
"Welsch",
"H.",
""
],
[
"Heyn",
"Ch.",
""
],
[
"Heitmann",
"D.",
""
],
[
"Kipp",
"T.",
""
]
] |
0704.3972 | Servio Perez | P.J. Salazar-Valencia, L.E. Bolivar-Marinez, and S.T.
Perez-Merchancano | Electronic Emition Properties of Bi Layer Novel Organic Semiconductor
Systems | 4 pages, 2 figures, 1 table, references. Submitted to the
Microelectronic Journal | null | null | null | cond-mat.mes-hall | null | The perylene-3,4,9,10-tetracarboxylic-dianhydride (PTCDA) and
1,4,5,8-naphthalene-tetracaboxylic-dianhydride (NTCDA) are planar pi-stacking
organic molecules that have been shown to be excellent model compounds for
studying the growth and optoelectronic properties of organic semiconductor thin
films, particularly organic diodes. Some observations have shown that this
molecules, particularly PTCDA a brick-like shaped molecule easily forms
well-ordered films on various substrates due to its unique crystal structure
which is characterized by flat lying molecules In this work we will explore
some energetic and optical characteristics such as heats of formation, optic
GAP energies, electronic transitions and others of novel tow layer systems of
alternate layers of PTCDA and NTCDA by means of the semiempirical methods
Parametric Model 3 (PM3) and Zerner's Intermediate Neglect of Differential
Overlap (ZINDO/S) in Configuration Interaction mode.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 16:35:54 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Salazar-Valencia",
"P. J.",
""
],
[
"Bolivar-Marinez",
"L. E.",
""
],
[
"Perez-Merchancano",
"S. T.",
""
]
] |
0704.3973 | Alexei Yu. Karlovich | Alexei Yu. Karlovich | Semi-Fredholm singular integral operators with piecewise continuous
coefficients on weighted variable Lebesgue spaces are Fredholm | 16 pages | null | null | null | math.FA | null | Suppose $\Gamma$ is a Carleson Jordan curve with logarithmic whirl points,
$\varrho$ is a Khvedelidze weight, $p:\Gamma\to(1,\infty)$ is a continuous
function satisfying $|p(\tau)-p(t)|\le -\mathrm{const}/\log|\tau-t|$ for
$|\tau-t|\le 1/2$, and $L^{p(\cdot)}(\Gamma,\varrho)$ is a weighted generalized
Lebesgue space with variable exponent. We prove that all semi-Fredholm
operators in the algebra of singular integral operators with $N\times N$ matrix
piecewise continuous coefficients are Fredholm on
$L_N^{p(\cdot)}(\Gamma,\varrho)$.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 16:40:26 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Karlovich",
"Alexei Yu.",
""
]
] |
0704.3974 | Servio Perez | Julian A. Zu\~niga, O.L. Hernandez-Rosero, and S.T. Perez-Merchancano | Rectangular Potential Barrier Affected by External Fields, Hydrostatic
Pressure and Impurities | 3 pages, 3 figures. Submitted to the Microelectronic Journal | null | null | null | cond-mat.mes-hall | null | In this work the influence of the electric and magnetic fields over a
tunneling particle in a rectangular potential barrier is shown, we have taken
into account the presence of an impurity at the barrier center and the effects
of a hydrostatic pressure parallel to the barrier height considering the
BenDaniel-Duke boundary conditions. Given that the particle is moving inside a
GaAs-AlxGa1-xAs-GaAs heterostructures it is evident a change in the
transmission coefficient due to the impurity concentration and the presence of
the hydrostatic pressure. The potential due to the presence of the impurity is
approximate with a second degree polynomial function that resolves the
discontinuity generated by heavily modifying the transmission coefficient.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 16:49:24 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Zuñiga",
"Julian A.",
""
],
[
"Hernandez-Rosero",
"O. L.",
""
],
[
"Perez-Merchancano",
"S. T.",
""
]
] |
0704.3975 | Audrey Cottet | Audrey Cottet | Spectroscopy and critical temperature of diffusive
superconducting/ferromagnetic hybrid structures with spin-active interfaces | 12 pages, 6 figures, to be published in Phys. Rev. B | Phys. Rev. B 76, 224505 (2007) | 10.1103/PhysRevB.76.224505 | null | cond-mat.supr-con | null | The description of the proximity effect in superconducting/ferromagnetic
heterostructures requires to use spin-dependent boundary conditions. Such
boundary conditions must take into account the spin dependence of the phase
shifts acquired by electrons upon scattering on the boundaries of ferromagnets.
The present article shows that this property can strongly affect the critical
temperature and the energy dependence of the density of states of diffusive
heterostructures. These effects should allow a better caracterisation of
diffusive superconductor/ferromagnet interfaces.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 16:50:52 GMT"
},
{
"version": "v2",
"created": "Tue, 17 Jul 2007 10:05:13 GMT"
},
{
"version": "v3",
"created": "Mon, 12 Nov 2007 20:46:17 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Cottet",
"Audrey",
""
]
] |
0704.3976 | Dirk Hofmann | Maria Manuel Clementino (University of Coimbra) and Dirk Hofmann
(University of Aveiro) | Lawvere completeness in Topology | null | null | null | null | math.CT math.GN | null | It is known since 1973 that Lawvere's notion of (Cauchy-)complete enriched
category is meaningful for metric spaces: it captures exactly Cauchy-complete
metric spaces. In this paper we introduce the corresponding notion of Lawvere
completeness for $(\mathbb{T},\mathsf{V})$-categories and show that it has an
interesting meaning for topological spaces and quasi-uniform spaces: for the
former ones means weak sobriety while for the latter means Cauchy completeness.
Further, we show that $\mathsf{V}$ has a canonical
$(\mathbb{T},\mathsf{V})$-category structure which plays a key role: it is
Lawvere-complete under reasonable conditions on the setting; permits us to
define a Yoneda embedding in the realm of $(\mathbb{T},\mathsf{V})$-categories.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 16:52:30 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Clementino",
"Maria Manuel",
"",
"University of Coimbra"
],
[
"Hofmann",
"Dirk",
"",
"University of Aveiro"
]
] |
0704.3977 | Servio Perez | M.M. Falla Sol\'orzano, L.E. Bolivar-Marinez, and S.T.
Perez-Merchancano | Electronic Properties of Eumelanin Monomers and Dimmers | 4 pages, 2 figures, 2 tables. Submitted to the Microelectronic
Journal | null | null | null | cond-mat.mes-hall | null | The melanin is a group of biological pigments commonly found in living
beings, it can be classified in three groups: eumelanin human beings,
pheomelanins in animals, and allomelanins in the vegetal kingdom. There is a
special interest in the eumelanin because this biopolymer exhibits the typical
properties of a semiconductor. Eumelanin is also responsible of the main
cellular photoprotection mechanisms in the human beings. The exact structural
pattern of eumelanin is not completely known yet, the planar molecules 5,
6-indolquinine and its reduced forms semiquinone and hydroquinone outline the
greater part of the biological pigment. In this work the structural, electronic
and optical properties of monomers in various charged states (0, -1) and
dimmers of eumelanin in vacuum, are found for the neutral state of charge, by
means of the Semiempirical methods MNDO, AM1, PM3 and ZINDO/S-CI
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 16:53:40 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Solórzano",
"M. M. Falla",
""
],
[
"Bolivar-Marinez",
"L. E.",
""
],
[
"Perez-Merchancano",
"S. T.",
""
]
] |
0704.3978 | Jose W. F. Valle | V. B. Semikoz and J. W. F. Valle | Lepton asymmetries and the growth of cosmological seed magnetic fields | 4 pages, no figures, final published version available online at
http://www.iop.org/EJ/abstract/1029-8479/2008/03/067 | JHEP 0803:067,2008 | 10.1088/1126-6708/2008/03/067 | IFIC/07-19 | hep-ph astro-ph | null | Primordial cosmological hypermagnetic fields polarize the early
Universe plasma prior to the electroweak phase transition (EWPT).
As a result of the long range parity violating gauge interaction present in
the Standard Model their magnitude gets amplified, opening a new, perturbative
way, of accounting for the observed intergalactic magnetic fields.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 17:45:58 GMT"
},
{
"version": "v2",
"created": "Fri, 28 Mar 2008 12:04:50 GMT"
}
] | 2009-09-17T00:00:00 | [
[
"Semikoz",
"V. B.",
""
],
[
"Valle",
"J. W. F.",
""
]
] |
0704.3979 | Javier Trujillo Bueno | Luca Belluzzi, Javier Trujillo Bueno and Egidio Landi Degl'Innocenti | The Magnetic Sensitivity of the Ba II D1 and D2 Lines of the Fraunhofer
Spectrum | 40 pages, 1 table and 19 figures. Accepted for publication in The
Astrophysical Journal (ApJ) | Astrophys.J.666:588-608,2007 | 10.1086/519078 | null | astro-ph | null | The physical interpretation of the spectral line polarization produced by the
joint action of the Hanle and Zeeman effects offers a unique opportunity to
obtain empirical information about hidden aspects of solar and stellar
magnetism. To this end, it is important to achieve a complete understanding of
the sensitivity of the emergent spectral line polarization to the presence of a
magnetic field. Here we present a detailed theoretical investigation on the
role of resonance scattering and magnetic fields on the polarization signals of
the Ba II D1 and D2 lines of the Fraunhofer spectrum, respectively at 4934 \AA\
and 4554 \AA. We adopt a three-level model of Ba II, and we take into account
the hyperfine structure that is shown by the $^{135}$Ba and $^{137}$Ba
isotopes. Despite of their relatively small abundance (18%), the contribution
coming from these two isotopes is indeed fundamental for the interpretation of
the polarization signals observed in these lines. We consider an optically thin
slab model, through which we can investigate in a rigorous way the essential
physical mechanisms involved (resonance polarization, Zeeman, Paschen-Back and
Hanle effects), avoiding complications due to radiative transfer effects. We
assume the slab to be illuminated from below by the photospheric solar
continuum radiation field, and we investigate the radiation scattered at 90
degrees, both in the absence and in the presence of magnetic fields,
deterministic and microturbulent. We show in particular the existence of a
differential magnetic sensitivity of the three-peak Q/I profile that is
observed in the D2 line in quiet regions close to the solar limb, which is of
great interest for magnetic field diagnostics.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 19:09:26 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Belluzzi",
"Luca",
""
],
[
"Bueno",
"Javier Trujillo",
""
],
[
"Degl'Innocenti",
"Egidio Landi",
""
]
] |
0704.3980 | Ivan Penkov | Ivan Penkov, Gregg Zuckerman | A construction of generalized Harish-Chandra modules for locally
reductive Lie algebras | null | null | null | null | math.RT | null | We study cohomological induction for a pair $(\frak g,\frak k)$, $\frak g$
being an infinite dimensional locally reductive Lie algebra and $\frak k
\subset\frak g$ being of the form $\frak k_0 + C_\gg(\frak k_0)$, where $\frak
k_0\subset\frak g$ is a finite dimensional reductive in $\frak g$ subalgebra
and $C_{\gg} (\frak k_0)$ is the centralizer of $\frak k_0$ in $\frak g$. We
prove a general non-vanishing and $\frak k$-finiteness theorem for the output.
This yields in particular simple $(\frak g,\frak k)$-modules of finite type
over $\frak k$ which are analogs of the fundamental series of generalized
Harish-Chandra modules constructed in \cite{PZ1} and \cite{PZ2}. We study
explicit versions of the construction when $\frak g$ is a root-reductive or
diagonal locally simple Lie algebra.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 17:13:09 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Penkov",
"Ivan",
""
],
[
"Zuckerman",
"Gregg",
""
]
] |
0704.3981 | Stephen West | Ben Gripaios and Stephen M. West | Anomaly Holography | 26 pages, references added | Nucl.Phys.B789:362-381,2008 | 10.1016/j.nuclphysb.2007.08.008 | OUTP-0705P | hep-ph hep-th | null | We consider, in the effective field theory context, anomalies of gauge field
theories on a slice of a five-dimensional, Anti-de Sitter geometry and their
four-dimensional, holographic duals. A consistent effective field theory
description can always be found, notwithstanding the presence of the anomalies
and without modifying the degrees of freedom of the theory. If anomalies do not
vanish, the d=4 theory contains additional pseudoscalar states, which are
either present in the low-energy theory as physical, light states, or are eaten
by (would-be massless) gauge bosons. We show that the pseudoscalars ensure that
global anomalies of the four-dimensional dual satisfy the 't Hooft matching
condition and comment on the relevance for warped models of electroweak
symmetry breaking.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 17:22:35 GMT"
},
{
"version": "v2",
"created": "Thu, 14 Feb 2008 10:46:30 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Gripaios",
"Ben",
""
],
[
"West",
"Stephen M.",
""
]
] |
0704.3982 | Hanfei Yan | Hanfei Yan, Jorg Maser, Albert Macrander, Qun Shen, Stefan Vogt, Brian
Stephenson and Hyon Chol Kang | Takagi-Taupin Description of X-ray Dynamical Diffraction from
Diffractive Optics with Large Numerical Aperture | 18 pages, 12 figures | null | 10.1103/PhysRevB.76.115438 | null | physics.optics physics.class-ph | null | We present a formalism of x-ray dynamical diffraction from volume diffractive
optics with large numerical aperture and high aspect ratio, in an analogy to
the Takagi-Taupin equations for strained single crystals. We derive a set of
basic equations for dynamical diffraction from volume diffractive optics, which
enable us to study the focusing property of these optics with various grating
profiles. We study volume diffractive optics that satisfy the Bragg condition
to various degrees, namely flat, tilted and wedged geometries, and derive the
curved geometries required for ultimate focusing. We show that the curved
geometries satisfy the Bragg condition everywhere and phase requirement for
point focusing, and effectively focus hard x-rays to a scale close to the
wavelength.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 17:25:35 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Yan",
"Hanfei",
""
],
[
"Maser",
"Jorg",
""
],
[
"Macrander",
"Albert",
""
],
[
"Shen",
"Qun",
""
],
[
"Vogt",
"Stefan",
""
],
[
"Stephenson",
"Brian",
""
],
[
"Kang",
"Hyon Chol",
""
]
] |
0704.3983 | Julien Barre | Julien Barre | Retrieving information from a noisy "knowledge network" | 10 pages, 4 figures. Writing of the last section improved; version
accepted in JSTAT | null | 10.1088/1742-5468/2007/08/P08015 | null | cond-mat.stat-mech cond-mat.dis-nn | null | We address the problem of retrieving information from a noisy version of the
``knowledge networks'' introduced by Maslov and Zhang. We map this problem onto
a disordered statistical mechanics model, which opens the door to many
analytical and numerical approaches. We give the replica symmetric solution,
compare with numerical simulations, and finally discuss an application to real
datas from the United States Senate.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 17:27:01 GMT"
},
{
"version": "v2",
"created": "Thu, 5 Jul 2007 07:35:06 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Barre",
"Julien",
""
]
] |
0704.3984 | Boris Krippa | Boris Krippa | Exact renormalisation group flow for ultracold Fermi gases in unitary
limit | 11 pages, Revtex, misprints corrected, references and comments added | J.Phys.A42:465002,2009 | 10.1088/1751-8113/42/46/465002 | null | cond-mat.supr-con nucl-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We study the exact renormalisation group flow for ultracold Fermi-gases in
unitary regime. We introduce a pairing field to describe the formation of the
Cooper pairs, and take a simple ansatz for the effective action. Set of
approximate flow equations for the effective couplings including boson and
fermionic fluctuations is derived. At some value of the running scale, the
system undergoes a phase transition to a gapped phase. The values of the energy
density, chemical potential, pairing gap and the corresponding proportionality
constants relating the interacting and non-interacting Fermi gases are
calculated. Standard mean field results are recovered if we omit the boson
loops.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 17:40:35 GMT"
},
{
"version": "v2",
"created": "Tue, 1 May 2007 16:17:39 GMT"
},
{
"version": "v3",
"created": "Tue, 8 May 2007 15:55:05 GMT"
},
{
"version": "v4",
"created": "Thu, 18 Dec 2008 16:25:38 GMT"
}
] | 2009-11-05T00:00:00 | [
[
"Krippa",
"Boris",
""
]
] |
0704.3985 | Ioannis Bakas | I. Bakas, C. Sourdis | Dirichlet sigma models and mean curvature flow | 77 pages, 21 figures | JHEP 0706:057,2007 | 10.1088/1126-6708/2007/06/057 | null | hep-th math-ph math.DG math.MP | null | The mean curvature flow describes the parabolic deformation of embedded
branes in Riemannian geometry driven by their extrinsic mean curvature vector,
which is typically associated to surface tension forces. It is the gradient
flow of the area functional, and, as such, it is naturally identified with the
boundary renormalization group equation of Dirichlet sigma models away from
conformality, to lowest order in perturbation theory. D-branes appear as fixed
points of this flow having conformally invariant boundary conditions. Simple
running solutions include the paper-clip and the hair-pin (or grim-reaper)
models on the plane, as well as scaling solutions associated to rational (p, q)
closed curves and the decay of two intersecting lines. Stability analysis is
performed in several cases while searching for transitions among different
brane configurations. The combination of Ricci with the mean curvature flow is
examined in detail together with several explicit examples of deforming curves
on curved backgrounds. Some general aspects of the mean curvature flow in
higher dimensional ambient spaces are also discussed and obtain consistent
truncations to lower dimensional systems. Selected physical applications are
mentioned in the text, including tachyon condensation in open string theory and
the resistive diffusion of force-free fields in magneto-hydrodynamics.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 17:48:53 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Bakas",
"I.",
""
],
[
"Sourdis",
"C.",
""
]
] |
0704.3986 | Sergiu Vacaru I. | Sergiu I. Vacaru | Parametric Nonholonomic Frame Transforms and Exact Solutions in Gravity | a latex 2e [11pt] variant corresponding to proofs for IJMMP, 54 pages | Int.J.Geom.Meth.Mod.Phys.04:1285-1334,2008 | 10.1142/S0219887807002570 | null | gr-qc hep-th math-ph math.DG math.MP | null | A generalized geometric method is developed for constructing exact solutions
of gravitational field equations in Einstein theory and generalizations. First,
we apply the formalism of nonholonomic frame deformations (formally considered
for nonholonomic manifolds and Finsler spaces) when the gravitational field
equations transform into systems of nonlinear partial differential equations
which can be integrated in general form. The new classes of solutions are
defined by generic off-diagonal metrics depending on integration functions on
one, two and three (or three and four) variables if we consider four (or five)
dimensional spacetimes. Second, we use a general scheme when one (two)
parameter families of exact solutions are defined by any source-free solutions
of Einstein's equations with one (two) Killing vector field(s). A successive
iteration procedure results in new classes of solutions characterized by an
infinite number of parameters for a non-Abelian group involving arbitrary
functions on one variable. Five classes of exact off-diagonal solutions are
constructed in vacuum Einstein and in string gravity describing solitonic
pp-wave interactions. We explore possible physical consequences of such
solutions derived from primary Schwarzschild or pp-wave metrics.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 17:49:57 GMT"
},
{
"version": "v2",
"created": "Tue, 1 May 2007 21:29:55 GMT"
},
{
"version": "v3",
"created": "Mon, 24 Sep 2007 20:32:45 GMT"
},
{
"version": "v4",
"created": "Mon, 19 Nov 2007 18:07:55 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Vacaru",
"Sergiu I.",
""
]
] |
0704.3987 | Ana Firan | Ana Firan and Ryszard Stroynowski | Internal conversions in Higgs decays to two photons | one .tex file and two .eps figures | Phys.Rev.D76:057301,2007 | 10.1103/PhysRevD.76.057301 | null | hep-ph | null | We evaluate the partial widths for internal conversions in the Higgs decays
to two photons. For the Higgs masses of interest at LHC in the range of 100-150
GeV, the conversions to pairs of fermions represent significant fraction of
Higgs decays.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 18:03:27 GMT"
},
{
"version": "v2",
"created": "Wed, 18 Jul 2007 22:26:10 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Firan",
"Ana",
""
],
[
"Stroynowski",
"Ryszard",
""
]
] |
0704.3988 | Nathanial P. Brown | Nathanial P. Brown and Andrew S. Toms | Three Applications of the Cuntz Semigroup | 10 pages | null | null | null | math.OA | null | Building on work of Elliott and coworkers, we present three applications of
the Cuntz semigroup: (i) for many simple C$^*$-algebras, the Thomsen semigroup
is recovered functorially from the Elliott invariant, and this yields a new
proof of Elliott's classification theorem for simple, unital AI algebras; (ii)
for the algebras in (i), classification of their Hilbert modules is similar to
the von Neumann algebra context; (iii) for the algebras in (i), approximate
unitary equivalence of self-adjoint operators is characterised in terms of the
Elliott invariant.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 18:03:28 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Brown",
"Nathanial P.",
""
],
[
"Toms",
"Andrew S.",
""
]
] |
0704.3989 | Michael Robinson | Michael Robinson | Instability of an equilibrium of a partial differential equation | 12 pages | null | null | null | math.AP math.DS | null | A nonlinear parabolic differential equation with a quadratic nonlinearity is
presented which has at least one equilibrium. The linearization about this
equilibrium is asymptotically stable, but by using a technique inspired by H.
Fujita, we show that the equilibrium is unstable in the nonlinear setting. The
perturbations used have the property that they are small in every $L^p$ norm,
yet they result in solutions which fail to be global.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 18:21:26 GMT"
},
{
"version": "v2",
"created": "Sun, 9 Sep 2007 23:10:03 GMT"
}
] | 2007-09-10T00:00:00 | [
[
"Robinson",
"Michael",
""
]
] |
0704.3990 | Elie Raphael | Alexei Chepelianskii (LPCT, LPS), Fr\'ed\'eric Chevy (LKB - Lhomond),
Elie Raphael (LPCT) | On capillary-gravity waves generated by a slow moving object | null | null | 10.1103/PhysRevLett.100.074504 | null | physics.class-ph | null | We investigate theoretically and experimentally the capillary-gravity waves
created by a small object moving steadily at the water-air interface along a
circular trajectory. It is well established that, for straight uniform motion,
no steady waves appear at velocities below the minimum phase velocity $c_{min}
= 23 \rm{cm \cdot s}^{-1}$. We show theoretically that no such velocity
threshold exists for a steady circular motion, for which, even at small
velocities, a finite wave drag is experienced by the object. This wave drag
originates from the emission of a spiral-like wave pattern. Our results are in
good agreement with direct experimental observations of the wave pattern
created by a circularly moving needle in contact with water. Our study leads to
new insights into the problem of animal locomotion at the water-air interface.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 18:24:09 GMT"
},
{
"version": "v2",
"created": "Tue, 1 Jan 2008 16:30:10 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Chepelianskii",
"Alexei",
"",
"LPCT, LPS"
],
[
"Chevy",
"Frédéric",
"",
"LKB - Lhomond"
],
[
"Raphael",
"Elie",
"",
"LPCT"
]
] |
0704.3991 | Alan Kogut | A. Kogut, J. Dunkley, C. L. Bennett, O. Dor\'e, B. Gold, M. Halpern,
G. Hinshaw, N. Jarosik, E. Komatsu, M. R. Nolta, N. Odegard, L. Page, D. N.
Spergel, G. S. Tucker, J. L. Weiland, E. Wollack, E. L. Wright | Three-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations:
Foreground Polarization | 9 pages with 8 figures. For higher quality figures, see the version
posted at http://lambda.gsfc.nasa.gov/product/map/dr2/map_bibliography.cfm | Astrophys.J.665:355-362,2007 | 10.1086/519754 | null | astro-ph | null | We present a full-sky model of polarized Galactic microwave emission based on
three years of observations by the Wilkinson Microwave Anisotropy Probe (WMAP)
at frequencies from 23 to 94 GHz. The model compares maps of the Stokes Q and U
components from each of the 5 WMAP frequency bands in order to separate
synchrotron from dust emission, taking into account the spatial and frequency
dependence of the synchrotron and dust components. This simple two-component
model of the interstellar medium accounts for at least 97% of the polarized
emission in the WMAP maps of the microwave sky. Synchrotron emission dominates
the polarized foregrounds at frequencies below 50 GHz, and is comparable to the
dust contribution at 65 GHz. The spectral index of the synchrotron component,
derived solely from polarization data, is -3.2 averaged over the full sky, with
a modestly flatter index on the Galactic plane. The synchrotron emission has
mean polarization fraction 2--4% in the Galactic plane and rising to over 20%
at high latitude, with prominent features such as the North Galactic Spur more
polarized than the diffuse component. Thermal dust emission has polarization
fraction 1% near the Galactic center, rising to 6% at the anti-center. Diffuse
emission from high-latitude dust is also polarized with mean fractional
polarization 0.036 +/- 0.011.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 18:38:26 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Kogut",
"A.",
""
],
[
"Dunkley",
"J.",
""
],
[
"Bennett",
"C. L.",
""
],
[
"Doré",
"O.",
""
],
[
"Gold",
"B.",
""
],
[
"Halpern",
"M.",
""
],
[
"Hinshaw",
"G.",
""
],
[
"Jarosik",
"N.",
""
],
[
"Komatsu",
"E.",
""
],
[
"Nolta",
"M. R.",
""
],
[
"Odegard",
"N.",
""
],
[
"Page",
"L.",
""
],
[
"Spergel",
"D. N.",
""
],
[
"Tucker",
"G. S.",
""
],
[
"Weiland",
"J. L.",
""
],
[
"Wollack",
"E.",
""
],
[
"Wright",
"E. L.",
""
]
] |
0704.3992 | Birbrair Lev | Lev Birbrair, Dirk Siersma | Metric Properties of Conflict Sets | 8 pages | null | null | null | math.MG math.AG | null | In this paper we show that the tangent cone of a conflict set in $R^n$ is a
linear affine cone over a conflict set of smaller dimension and has dimension
$n-1$. Moreover we give an example where the conflict sets is not normally
embedded and not locally bi-Lipschitz equivalent to the corresponding tangent
cone.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 18:41:43 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Birbrair",
"Lev",
""
],
[
"Siersma",
"Dirk",
""
]
] |
0704.3993 | Sergey Fedosov | S. N. Fedosov, A. E. Sergeeva, A. F. Butenko | Depolarization Currents in Fresh and Aged Corona Poled P(VDF-TFE) Films | 5 pages, 2 figures | null | null | null | cond-mat.mtrl-sci | null | Using short circuit and open circuit modifications of the thermally
stimulated depolarization current technique, relaxation currents have been
measured in corona poled copolymer of vinylidene fluoride with
tetrafluoroethylene in samples stored after poling for either 1 day, or 16
month. Two well structured peaks observed in aged samples were attributed to
relaxation of electret and ferroelectric components of the remnant
polarization. In fresh samples the two components were mixed forming one broad
peak. Relaxation of the space charge caused inversion of the current in the
open circuit mode both in fresh and in aged samples. Space charge peaks
extracted from the total current by appropriate calculations have shown that
the trapped charges were more stable than the polarization. It was suggested
that both the electret and the ferroelectric components of the remnant
polarization were accompanied by either space, or surface charges.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 19:16:57 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Fedosov",
"S. N.",
""
],
[
"Sergeeva",
"A. E.",
""
],
[
"Butenko",
"A. F.",
""
]
] |
0704.3994 | Dawei Chen | Dawei Chen | Covers of Elliptic Curves and the Lower Bound for Slopes of Effective
Divisors on $\bar{\mathcal M}_{g}$ | 41 pages, 19 figures | null | null | null | math.AG math.CO math.GT | null | Consider genus $g$ curves that admit degree $d$ covers to elliptic curves
only branched at one point with a fixed ramification type. The locus of such
covers forms a one parameter family $Y$ that naturally maps into the moduli
space of stable genus $g$ curves $\bar{\mathcal M}_{g}$. We study the geometry
of $Y$, and produce a combinatorial method by which to investigate its slope,
irreducible components, genus and orbifold points. As a by-product of our
approach, we find some equalities from classical number theory. Moreover, a
correspondence between our method and the viewpoint of square-tiled surfaces is
established. We also use our results to study the lower bound for slopes of
effective divisors on $\bar{\mathcal M}_{g}$.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 18:43:14 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Chen",
"Dawei",
""
]
] |
0704.3995 | Masahico Saito | Kheira Ameur, Masahico Saito | Polynomial cocycles of Alexander quandles and applications | null | null | null | null | math.GT | null | Cocycles are constructed by polynomial expressions for Alexander quandles. As
applications, non-triviality of some quandle homology groups are proved, and
quandle cocycle invariants of knots are studied. In particular, for an infinite
family of quandles, the non-triviality of quandle homology groups is proved for
all odd dimensions.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 18:47:03 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Ameur",
"Kheira",
""
],
[
"Saito",
"Masahico",
""
]
] |
0704.3996 | Po-Shan Leang | Peter Arnold and Po-Shan Leang | Lessons from Non-Abelian Plasma Instabilities in Two Spatial Dimensions | 15 pages, 10 figures | Phys.Rev.D76:065012,2007 | 10.1103/PhysRevD.76.065012 | null | hep-ph nucl-th | null | Plasma instabilities can play a fundamental role in quark-gluon plasma
equilibration in the high energy (weak coupling) limit. Early simulations of
the evolution of plasma instabilities in non-abelian gauge theory, performed in
one spatial dimension, found behavior qualitatively similar to traditional QED
plasmas. Later simulations of the fully three-dimensional theory found
different behavior, unlike traditional QED plasmas. To shed light on the origin
of this difference, we study the intermediate case of two spatial dimensions.
Depending on how the "two-dimensional'' theory is formulated, we can obtain
either behavior.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 19:00:21 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Arnold",
"Peter",
""
],
[
"Leang",
"Po-Shan",
""
]
] |
0704.3997 | Gennadiy Burlak | G.N. Burlak, A.B. Klimov | The solitons redistribution in Bose-Einstein condensate in quasiperiodic
optical lattice | 16 pages, 6 figures | null | 10.1016/j.physleta.2007.05.012 | null | nlin.PS | null | We numerically study the dynamical excitations in Bose-Einstein condensate
(BEC) placed in periodic and quasi-periodic 2D optical lattice (OL). In case of
the repulsive mean-field interaction the BEC quantum tunnelling leads to a
progressive soliton's splitting and generating of secondary solitons, which
migrate to closest trapping potential minima. A nontrivial soliton dynamics
appears when a series of pi-pulses (phase kicks) are applied to the optical
lattice. Such sudden perturbation produces a dynamic redistribution of the
secondary solitons, leading to a formation of an artificial solitonic
superlattice. Different geometries of OL are analyzed.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 19:03:32 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Burlak",
"G. N.",
""
],
[
"Klimov",
"A. B.",
""
]
] |
0704.3998 | Arnold W. Miller | Arnold W. Miller | Long Borel Hierarchies | null | null | null | null | math.LO | null | We show that it is relatively consistent with ZF that the Borel hierarchy on
the reals has length $\omega_2$. This implies that $\omega_1$ has countable
cofinality, so the axiom of choice fails very badly in our model. A similar
argument produces models of ZF in which the Borel hierarchy has length any
given limit ordinal less than $\omega_2$, e.g., $\omega$ or
$\omega_1+\omega_1$.
Latex2e: 24 pages plus 8 page appendix Latest version at:
www.math.wisc.edu/~miller
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 19:06:50 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Miller",
"Arnold W.",
""
]
] |
0704.3999 | Julius Kuti | Chuan Liu | Strongly Interacting Higgs Sector Without Technicolor | 156 pages, 25 figures, Ph.D. Thesis (1994) | null | null | null | hep-ph | null | Several years ago, we proposed a modification of the Standard Model, in which
the Higgs sector was stabilized by the addition of higher derivative operators,
similar to Lee-Wick Electrodynamics. We studied this theory extensively, both
using continuum Hamiltonian and path integral methods. We also reported
detailed lattice studies of the higher derivative Higgs sector. In view of some
recent revived interest in our original idea, we are providing here our
extensive notes from the time period on this topic. The key results were
already published in our papers at that time. The many additional details that
we make available here were previously available only in Chuan Liu's UCSD Ph.D.
thesis (1994). Very recently, our idea has been revived by other groups. In
view of the renewed interest, and to perhaps correct some misconceptions in the
literature, we are here making our original extensive notes available to the
wider community.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 19:07:26 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Liu",
"Chuan",
""
]
] |
0704.4000 | Erhan Iltan | E. O. Iltan | Radiative lepton flavor violating decays in the Randall Sundrum
background with localized leptons | 23 pages, 10 figures, 2 tables | Int.J.Mod.Phys.A23:1055-1073,2008 | 10.1142/S0217751X08039748 | null | hep-ph | null | We study the radiative lepton flavor violating l_i -> l_j\gamma decays in the
two Higgs doublet model, respecting the Randall Sundrum scenario and estimate
the contributions of the KK modes of left (right) handed charged lepton
doublets (singlets) on the branching ratios. We observe that the branching
ratios are sensitive to the contributions of the charged lepton KK modes.
| [
{
"version": "v1",
"created": "Mon, 30 Apr 2007 19:32:07 GMT"
},
{
"version": "v2",
"created": "Mon, 25 Feb 2008 12:24:06 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Iltan",
"E. O.",
""
]
] |
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