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timestamp[s] | authors_parsed
sequence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
0707.3830 | Neven Bilic | Neven Bilic, Branko Guberina, Raul Horvat, Hrvoje Nikolic and Hrvoje
Stefancic | On Cosmological Implications of Gravitational Trace Anomaly | 11 pages, equation (4) corrected, discussions expanded, references
added, results unchanged, to appear in PLB | Phys.Lett.B657:232-237,2007 | 10.1016/j.physletb.2007.09.067 | null | gr-qc astro-ph hep-th | null | We study the infrared effective theory of gravity that stems from the quantum
trace anomaly. Quantum fluctuations of the metric induce running of the
cosmological constant and the Newton constant at cosmological scales. By
imposing the generalized Bianchi identity we obtain a prediction for the scale
dependence of the dark matter and dark energy densities in terms of the
parameters of the underlying conformal theory. For certain values of the model
parameters the dark energy equation of state and the observed spectral index of
the primordial density fluctuations can be simultaneously reproduced.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 14:43:32 GMT"
},
{
"version": "v2",
"created": "Tue, 31 Jul 2007 13:25:49 GMT"
},
{
"version": "v3",
"created": "Mon, 15 Oct 2007 13:11:36 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Bilic",
"Neven",
""
],
[
"Guberina",
"Branko",
""
],
[
"Horvat",
"Raul",
""
],
[
"Nikolic",
"Hrvoje",
""
],
[
"Stefancic",
"Hrvoje",
""
]
] |
0707.3831 | Douglas Galvao | David L. Azevedo, Fernando Sato, Antonio Gomes de Sousa Filho, Douglas
S. Galvao | Cobaltocene Encapsulation Into Single-walled Carbon Nanotubes: A
Molecular Dynamics Investigation | 5 pages, 3 figures | null | null | null | cond-mat.mtrl-sci | null | Recently (PRL 96, 106804 (2006)) it was suggested that cobaltocene(CC)
molecules encapsulated into (7,7) carbon nanotubes (CNT@(7,7)) could be the
basis for new spintronic devices. We show here based on impact molecular
dynamics and DFT calculations that when dynamical aspects are explicitly
considered the CC encapsulation into CNT@(7,7) does not occur, it is prevented
by a dynamic barrier mainly due to van der Waals interactions. Our results show
that CNT@(13,0) having enough axial space for encapsulation but no enough one
to allow freely rotation of the cobaltocene molecule would be a feasible
candidate to such application.
| [
{
"version": "v1",
"created": "Wed, 25 Jul 2007 21:52:58 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Azevedo",
"David L.",
""
],
[
"Sato",
"Fernando",
""
],
[
"Filho",
"Antonio Gomes de Sousa",
""
],
[
"Galvao",
"Douglas S.",
""
]
] |
0707.3832 | Daniel Green | Daniel Green | Reheating Closed String Inflation | 17 pages, v2: fixed typos and added refs, v3: fixed typos, added refs
and title change | Phys.Rev.D76:103504,2007 | 10.1103/PhysRevD.76.103504 | SU-ITP-07/10, SLAC-PUB-12693 | hep-th astro-ph hep-ph | null | Protecting the inflationary potential from quantum corrections typically
requires symmetries that constrain the form of couplings of the inflaton to
other sectors. We will explore how these restrictions affect reheating in
models with UV completions. In particular, we look at how reheating occurs when
inflation is governed by closed strings, using N-flation as an example. We find
that coupling the inflaton preferentially to the Standard Model is difficult,
and hidden sectors are typically reheated. Observational constraints are only
met by a fraction of the models. In some working models, relativistic relics in
the hidden sector provide dark matter candidates with masses that range from
keV to PeV, with lighter masses being preferred.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 18:59:28 GMT"
},
{
"version": "v2",
"created": "Tue, 31 Jul 2007 20:39:39 GMT"
},
{
"version": "v3",
"created": "Tue, 2 Oct 2007 18:10:01 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Green",
"Daniel",
""
]
] |
0707.3833 | Joshua Eisner | J.A. Eisner, L.A. Hillenbrand, R.J. White, J.S. Bloom, R.L. Akeson,
C.H. Blake | Near-Infrared Interferometric, Spectroscopic, and Photometric Monitoring
of T Tauri Inner Disks | 33 pages, 6 figures. Accepted for publication in ApJ | Astrophys.J. 669 (2007) 1072-1084 | 10.1086/521874 | null | astro-ph | null | We present high angular resolution observations with the Keck Interferometer,
high dispersion spectroscopic observations with Keck/NIRSPEC, and near-IR
photometric observations from PAIRITEL of a sample of 11 solar-type T Tauri
stars in 9 systems. We use these observations to probe the circumstellar
material within 1 AU of these young stars, measuring the
circumstellar-to-stellar flux ratios and angular size scales of the 2.2 micron
emission. Our sample spans a range of stellar luminosities and mass accretion
rates, allowing investigation of potential correlations between inner disk
properties and stellar or accretion properties. We suggest that the mechanism
by which the dusty inner disk is truncated may depend on the accretion rate of
the source; in objects with low accretion rates, the stellar magnetospheres may
truncate the disks, while sublimation may truncate dusty disks around sources
with higher accretion rates. We have also included in our sample objects that
are known to be highly variable (based on previous photometric and
spectroscopic observations), and for several sources, we obtained multiple
epochs of spectroscopic and interferometric data, supplemented by near-IR
photometric monitoring, to search for inner disk variability. While
time-variable veilings and accretion rates are observed in some sources, no
strong evidence for inner disk pulsation is found.
| [
{
"version": "v1",
"created": "Wed, 25 Jul 2007 22:19:43 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Eisner",
"J. A.",
""
],
[
"Hillenbrand",
"L. A.",
""
],
[
"White",
"R. J.",
""
],
[
"Bloom",
"J. S.",
""
],
[
"Akeson",
"R. L.",
""
],
[
"Blake",
"C. H.",
""
]
] |
0707.3834 | Dominic Meiser | D. Meiser, Jun Ye, and M. J. Holland | Spin squeezing in optical lattice clocks via lattice-based QND
measurements | Substantially expanded version | null | 10.1088/1367-2630/10/7/073014 | null | quant-ph physics.atom-ph | null | Quantum projection noise will soon limit the best achievable precision of
optical atomic clocks based on lattice-confined neutral atoms. Squeezing the
collective atomic pseudo-spin via measurement of the clock state populations
during Ramsey interrogation suppresses the projection noise. We show here that
the lattice laser field can be used to perform ideal quantum non-demolition
measurements without clock shifts or decoherence and explore the feasibility of
such an approach in theory with the lattice field confined in a ring-resonator.
Detection of the motional sideband due to the atomic vibration in the lattice
wells can yield signal sizes a hundredfold above the projection noise limit.
| [
{
"version": "v1",
"created": "Wed, 25 Jul 2007 22:20:27 GMT"
},
{
"version": "v2",
"created": "Mon, 29 Oct 2007 22:44:15 GMT"
},
{
"version": "v3",
"created": "Thu, 8 May 2008 16:12:57 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Meiser",
"D.",
""
],
[
"Ye",
"Jun",
""
],
[
"Holland",
"M. J.",
""
]
] |
0707.3835 | Michael McCooey | Michael McCooey | Symmetry groups of non-simply-connected four-manifolds | 16 pages. An earlier version erroneously asserted that surfaces fixed
by certain involutions were orientable, and that error invalidated a later
proof. This version discusses the problem and corrects the error | null | null | null | math.GT math.AT | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Let $M$ be a closed, connected, orientable topological four-manifold with
$H_1(M)$ nontrivial and free abelian, $b_2(M)\ne 0, 2$, and $\chi(M)\ne 0$. We
show that if $G$ is a finite group of 2-rank $\le 1$ which admits a
homologically trivial, locally linear, effective action on $M$, then $G$ must
be cyclic.
With additional assumptions to ensure orientability of some components of the
singular set (e.g. if $G$ acts by symplectic symmetries, or preserving a spin
structure), we also rule out $C_2 \times C_2$ actions.
The proofs use equivariant cohomology, localization, and a careful study of
the first cohomology groups of the (potential) singular set.
| [
{
"version": "v1",
"created": "Wed, 25 Jul 2007 22:28:25 GMT"
},
{
"version": "v2",
"created": "Thu, 25 Jul 2013 19:15:18 GMT"
}
] | 2013-07-26T00:00:00 | [
[
"McCooey",
"Michael",
""
]
] |
0707.3836 | Evgeny Plekhanov | Adolfo Avella and Ferdinando Mancini | The charge and spin sectors of the $t$-$t'$ Hubbard model | null | Physica C 408, 284 (2004) | 10.1016/j.physc.2004.02.147 | null | cond-mat.str-el | null | The charge and spin sectors, which are intimately coupled to the fermionic
one, of the $t$-$t'$ Hubbard model have been computed self-consistently within
the two-pole approximation. The relevant unknown correlators appearing in the
causal bosonic propagators have been computed by enforcing the constraints
dictated by the hydrodynamics and the algebra of the composite operators coming
into play. The proposed scheme of approximation extends previous calculations
made for the fermionic sector of the $t$-$t'$ Hubbard model and the bosonic
sector of the Hubbard model, which showed to be very effective to describe the
overdoped region of cuprates (the former) and the magnetic response of their
parent compounds (the latter).
| [
{
"version": "v1",
"created": "Wed, 25 Jul 2007 22:38:56 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Avella",
"Adolfo",
""
],
[
"Mancini",
"Ferdinando",
""
]
] |
0707.3837 | Rapha\"el Rossignol | Michel Benaim, Itai Benjamini and Raphael Rossignol | Effective resistance on random electrical networks | This paper has been withdrawn | null | null | null | math.PR math-ph math.MP | null | This paper has been withdrawn. See v1 still available to understand the
problem: Proposition 2.2 is false. The error in the proof is in claim (3).
Then, the whole paper collapses. We do not have any correction for now. We
apologize to everyone.
| [
{
"version": "v1",
"created": "Wed, 25 Jul 2007 22:44:46 GMT"
},
{
"version": "v2",
"created": "Tue, 31 Jul 2007 19:30:57 GMT"
}
] | 2007-07-31T00:00:00 | [
[
"Benaim",
"Michel",
""
],
[
"Benjamini",
"Itai",
""
],
[
"Rossignol",
"Raphael",
""
]
] |
0707.3838 | Evgeny Plekhanov | Adolfo Avella, Ferdinando Mancini and Evgeny Plekhanov | Ergodicity in Strongly Correlated Systems | null | Condens. Matter Phys. 9, 485 (2006) | null | null | cond-mat.str-el cond-mat.soft | null | We present a concise, but systematic, review of the ergodicity issue in
strongly correlated systems. After giving a brief historical overview, we
analyze the issue within the Green's function formalism by means of the
equations of motion approach. By means of this analysis, we are able to
individuate the primary source of non-ergodic dynamics for a generic operator
and also to give a recipe to compute unknown quantities characterizing such a
behavior within the Composite Operator Method. Finally, we present examples of
non-trivial strongly correlated systems where it is possible to find a
non-ergodic behavior.
| [
{
"version": "v1",
"created": "Wed, 25 Jul 2007 23:02:20 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Avella",
"Adolfo",
""
],
[
"Mancini",
"Ferdinando",
""
],
[
"Plekhanov",
"Evgeny",
""
]
] |
0707.3839 | Evgeny Plekhanov | Ferdinando Mancini | A class of solvable models in Condensed Matter Physics | null | Condens. Matter Phys. 9, 393 (2006) | null | null | cond-mat.str-el | null | In this paper, we show that there is a large class of fermionic systems for
which it is possible to find, for any dimension, a finite closed set of
eigenoperators and eigenvalues of the Hamiltonian. Then, the hierarchy of the
equations of motion closes and analytical expressions for the Green's functions
are obtained in terms of a finite number of parameters, to be self-consistently
determined. Several examples are given. In particular, for these examples it is
shown that in the one-dimensional case it is possible to derive by means of
algebraic constraints a set of equations which allow us to determine the
self-consistent parameters and to obtain a complete exact solution.
| [
{
"version": "v1",
"created": "Wed, 25 Jul 2007 23:06:46 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Mancini",
"Ferdinando",
""
]
] |
0707.3840 | Evgeny Plekhanov | Ferdinando Mancini and Adolfo Avella | Green's Function Formalism for Highly Correlated Systems | null | Condens. Matter Phys. 9, 569 (2006) | null | null | cond-mat.str-el | null | We present the Composite Operator Method (COM) as a modern approach to the
study of strongly correlated electronic systems, based on the equation of
motion and Green's function method. COM uses propagators of composite operators
as building blocks at the basis of approximate calculations and algebra
constrains to fix the representation of Green's functions in order to maintain
the algebraic and symmetry properties.
| [
{
"version": "v1",
"created": "Wed, 25 Jul 2007 23:11:29 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Mancini",
"Ferdinando",
""
],
[
"Avella",
"Adolfo",
""
]
] |
0707.3841 | Mois\'es Mart\'inez-Mares | V. Dominguez-Rocha, C. Zagoya, and M. Martinez-Mares | Poynting's theorem for planes waves at an interface: a scattering matrix
approach | 5 pages, 3 figures, submitted to Am. J. Phys | Am. J. Phys. 76 (7), 621-625 (2008) | 10.1119/1.2870269 | null | physics.class-ph | null | We apply the Poynting theorem to the scattering of monochromatic
electromagnetic planes waves with normal incidence to the interface of two
different media. We write this energy conservation theorem to introduce a
natural definition of the scattering matrix S. For the dielectric-dielectric
interface the balance equation lead us to the energy flux conservation which
express one of the properties of S: it is a unitary matrix. For the
dielectric-conductor interface the scattering matrix is no longer unitary due
to the presence of losses at the conductor. However, the dissipative term
appearing in the Poynting theorem can be interpreted as a single absorbing mode
at the conductor such that a whole S, satisfying flux conservation and
containing this absorbing mode, can be defined. This is a simplest version of a
model introduced in the current literature to describe losses in more complex
systems.
| [
{
"version": "v1",
"created": "Wed, 25 Jul 2007 23:27:07 GMT"
}
] | 2008-10-30T00:00:00 | [
[
"Dominguez-Rocha",
"V.",
""
],
[
"Zagoya",
"C.",
""
],
[
"Martinez-Mares",
"M.",
""
]
] |
0707.3842 | John Toner | John Toner | Quenched Dislocation Enhanced Supersolid Ordering | 5 pages, 2 figures | null | 10.1103/PhysRevLett.100.035302 | null | cond-mat.other cond-mat.stat-mech | null | I show using Landau theory that quenched dislocations can facilitate the
supersolid (SS) to normal solid (NS) transition, making it possible for the
transition to occur even if it does not in a dislocation-free crystal. I make
detailed predictions for the dependence of the SS to NS transition temperature
T_c(L), superfluid density %\rho_S(T, L), and specific heat C(T,L) on
temperature T and dislocation spacing L, all of which can be tested against
experiments. The results should also be applicable to an enormous variety of
other systems, including, e.g., ferromagnets.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 01:20:50 GMT"
},
{
"version": "v2",
"created": "Fri, 27 Jul 2007 18:08:12 GMT"
},
{
"version": "v3",
"created": "Thu, 15 Nov 2007 00:07:53 GMT"
},
{
"version": "v4",
"created": "Thu, 29 Nov 2007 01:04:33 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Toner",
"John",
""
]
] |
0707.3843 | Massimo Tinto | Massimo Tinto, John W. Armstrong, and Frank B. Estabrook | Modulator noise suppression in the LISA Time-Delay Interferometric
combinations | 17 pages, 5 figures. Submitted to: Phys. Rev. D 15 | Class.Quant.Grav.25:015008,2008 | 10.1088/0264-9381/25/1/015008 | null | gr-qc | null | We previously showed how the measurements of some eighteen time series of
relative frequency or phase shifts could be combined (1) to cancel the phase
noise of the lasers, (2) to cancel the Doppler fluctuations due to non-inertial
motions of the six optical benches, and (3) to remove the phase noise of the
onboard reference oscillators required to track the photodetector fringes, all
the while preserving signals from passinggravitational waves. Here we analyze
the effect of the additional noise due to the optical modulators used for
removing the phase fluctuations of the onboard reference oscillators. We use a
recently measured noise spectrum of an individual modulator to quantify the
contribution of modulator noise to the first and second-generation Time-Delay
Interferometric (TDI) combinations as a function of the modulation frequency.
We show that modulator noise can be made smaller than the expected proof-mass
acceleration and optical-path noises if the modulation frequencies are larger
than $\approx 682$ MHz in the case of the unequal-arm Michelson TDI combination
$X_1$, $\approx 1.08$ GHz for the Sagnac TDI combination $\alpha_1$, and
$\approx 706$ MHz for the symmetrical Sagnac TDI combination $\zeta_1$. These
modulation frequencies are substantially smaller than previously estimated and
may lead to less stringent requirements on the LISA's oscillator noise
calibration subsystem.
| [
{
"version": "v1",
"created": "Wed, 25 Jul 2007 23:43:11 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Tinto",
"Massimo",
""
],
[
"Armstrong",
"John W.",
""
],
[
"Estabrook",
"Frank B.",
""
]
] |
0707.3844 | Huey-Wen Lin | Huey-Wen Lin | Nucleon Structure and Hyperon Form factor from Lattice QCD | 11th International Baryons Conference, Seoul, Korea; 18 pages and 11
figures | null | null | JLAB-THY-07-687 | hep-lat | null | In this work, I report the latest lattice QCD calculations of nucleon and
hyperon structure from chiral fermions in 2+1-flavor dynamical simulations. All
calculations are done with a chirally symmetric fermion action, domain-wall
fermions, for valence quarks. % I begin with the latest lattice results on the
nucleon structure, focusing on results from RBC/UKQCD using 2+1-flavor chiral
fermion actions. We find the chiral-extrapolated axial coupling constant at
physical pion mass point to be 1.23(5), consistent with experimental value. The
renormalization constants for the structure functions are obtained from
RI/MOM-scheme non-perturbative renormalization. We find first moments of the
polarized and unpolarized nucleon structure functions at zero transfer momentum
to be 0.133(13) and 0.203(23) respectively, using continuum chiral
extrapolation. These are consistent with the experimental values, unlike
previous calculations which have been 50% larger. We also have a prediction for
the transversity, which we find to be 0.56(4). The twist-3 matrix element is
consistent with zero which agrees with the prediction of the Wandzura-Wilczek
relation.
In the second half of this work, I report an indirect dynamical estimation of
the strangeness proton magnetic moments using mixed actions. With the analysis
of hyperon form factors and using charge symmetry, the strangeness of proton is
found to be $-0.066(26)$, consistent with the Adelaide-JLab Collaboration's
result. The hyperon $\Sigma$ and $\Xi$ axial coupling constants are also
performed for the first time in a lattice calculation, $g_{\Sigma\Sigma}=
0.441(14)$ and $g_{\Xi\Xi} = -0.277(11)$.
| [
{
"version": "v1",
"created": "Wed, 25 Jul 2007 23:51:34 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Lin",
"Huey-Wen",
""
]
] |
0707.3845 | Julia Pevtsova | Jon F. Carlson (University of Georgia), Eric M. Friedlander
(Northwestern), Julia Pevtsova (University of Washington) | Modules of constant Jordan type | 47 pages | null | null | null | math.RT | null | We introduce the class of modules of constant Jordan type for a finite group
scheme $G$ over a field $k$ of characteristic $p > 0$. This class is closed
under taking direct sums, tensor products, duals, Heller shifts and direct
summands, and includes endotrivial modules. It contains all modules in an
Auslander-Reiten component which has at least one module in the class. Highly
non-trivial examples are constructed using cohomological techniques. We offer
conjectures suggesting that there are strong conditions on a partition to be
the Jordan type associated to a module of constant Jordan type.
| [
{
"version": "v1",
"created": "Wed, 25 Jul 2007 23:56:07 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Carlson",
"Jon F.",
"",
"University of Georgia"
],
[
"Friedlander",
"Eric M.",
"",
"Northwestern"
],
[
"Pevtsova",
"Julia",
"",
"University of Washington"
]
] |
0707.3846 | Murray Olsen Dr | M.K. Olsen, A.S. Bradley, S.A. Haine and J.J. Hope | Quantum statistical measurements of an atom laser beam | 4 pages, 2 fugures | Nuclear Physics A, 790, 733c (2007) | 10.1016/j.nuclphysa.2007.03.123 | null | physics.atom-ph physics.optics | null | We describe a scheme, operating in a manner analogous to a reversed Raman
output coupler, for measuring the phase-sensitive quadrature statistics of an
atom laser beam. This scheme allows for the transferral of the atomic field
statistics to an optical field, for which the quantum statistics may then be
measured using the well-developed technology of optical homodyne measurement.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 00:44:52 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Olsen",
"M. K.",
""
],
[
"Bradley",
"A. S.",
""
],
[
"Haine",
"S. A.",
""
],
[
"Hope",
"J. J.",
""
]
] |
0707.3847 | Grzegorz Kowal | Grzegorz Kowal, A. Lazarian | Aspects of Density Fluctuations in Compressible MHD Turbulence | 10 pages, 7 figures, Proceeings for 6th Annual International
Astrophysics Conference, Honolulu, 2007 | AIP Conf.Proc.932:421-430,2007 | 10.1063/1.2778995 | null | astro-ph | null | We study scaling relations of compressible isothermal strongly magnetized
turbulence using numerical simulations with resolution 512$^3$. We find a good
correspondence of our results with the Fleck (1996) model of compressible
hydrodynamic turbulence. In particular, we find that the density-weighted
velocity, i.e. $\boldsymbol{u} \equiv \rho^{1/3} \boldsymbol{v}$, proposed in
Kritsuk et al. (2007) obeys the Kolmogorov scaling, i.e. ${\cal E}_{u}(k)\sim
k^{-5/3}$ for the high Mach number turbulence. Similarly, we find that the
exponents of the third order structure functions for $\boldsymbol{u}$ stay
equal to unity for all Mach numbers studied. The scaling of higher order
correlations obeys the She-L\'{e}v\^{e}que (1994) scalings corresponding to the
two-dimensional dissipative structures, and this result does not change with
the Mach number either. In contrast to velocity $\boldsymbol{v}$ which exhibits
different scaling parallel and perpendicular to the local magnetic field, the
scaling of $\boldsymbol{u}$ is similar in both directions. In addition, we find
that the peaks of density create a hierarchy in which both physical and column
densities decrease with the scale in accordance to the Fleck (1996)
predictions. This hierarchy can be related ubiquitous small ionized and neutral
structures (SINS) in the interstellar gas. We believe that studies of
statistics of the column density peaks can provide both consistency check for
the turbulence velocity studies and insight into supersonic turbulence, when
the velocity information is not available.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 17:14:44 GMT"
}
] | 2009-06-23T00:00:00 | [
[
"Kowal",
"Grzegorz",
""
],
[
"Lazarian",
"A.",
""
]
] |
0707.3848 | Nasir Ganikhodjaev | Nasir Ganikhodjaev, Fatimah Abdul Razak | Correlation Inequalities for Generalized Potts Model: General Griffiths'
Inequalities | 14 pages | null | null | null | math-ph math.MP math.PR | null | In this paper, correlation inequalities which have been considered on Ising
model are extended to q-Potts model. It is considered on generalized Potts
model with interaction of any number of spins. We replace the set of spin
values $F=\{1,2,..., q\}$ by the centered set $F=\{-(q-1)/2,-(q-3)/2,...
,(q-3)/2,(q-1)/2\}$. Let $N$ be the subset of one-dimensional lattice with $n$
vertices, $\g=(\s_1,\s_2,...,\s_n):N \to F^c$ be a configuration where
${(\s_i)}_\g$ is the number which appears as the ith spin (component) in $\g$
and $\s_i$ be a random variable whose value at $\g$ is ${(\s_i)}_\g$. Define
$\s^R=\prod_{i \in R}\s_i$ for any list $R$ where any $i \in R$ implies that $i
\in N$. We first prove that $<\s^R > \ge 0$ then we prove that for any two
lists $R$ and $S$, we have $<\s^R \s^S >- < \s^R > < \s^S > \ge 0$.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 01:10:44 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Ganikhodjaev",
"Nasir",
""
],
[
"Razak",
"Fatimah Abdul",
""
]
] |
0707.3849 | Philipp Gerhold | P. Gerhold, K. Jansen | The phase structure of a chirally invariant lattice Higgs-Yukawa model -
numerical simulations | 14 pages, 11 figures | JHEP0710:001,2007 | 10.1088/1126-6708/2007/10/001 | HU-EP-07/28, DESY 07-108 | hep-lat | null | The phase diagram of a chirally invariant lattice Higgs-Yukawa model is
explored by means of numerical simulations. The results revealing a rich phase
structure are compared to analytical large Nf calculations which we performed
earlier. The analytical and numerical results are in excellent agreement at
large values of Nf. In the opposite case the large Nf computation still gives a
good qualitative description of the phase diagram. In particular we find
numerical evidence for the predicted ferrimagnetic phase at intermediate values
of the Yukawa coupling constant and for the symmetric phase at strong Yukawa
couplings. Emphasis is put on the finite size effects which can hide the
existence of the latter symmetric phase.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 01:31:17 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Gerhold",
"P.",
""
],
[
"Jansen",
"K.",
""
]
] |
0707.3850 | Tako Kotani | Takao Kotani and Mark van Schilfgaarde | Spin wave dispersion based on the quasiparticle self-consistent $GW$
method: NiO, MnO and $\alpha$-MnAs | V2: add another figure for SW life time. Formalism is detailed | J. Phys.: Condens. Matter 20 (2008) 295214 | 10.1088/0953-8984/20/29/295214 | null | cond-mat.mtrl-sci cond-mat.other | null | We present spin wave dispersions in MnO, NiO, and $\alpha$-MnAs based on the
quasiparticle self-consistent $GW$ method (\qsgw), which determines an optimum
quasiparticle picture. For MnO and NiO, \qsgw results are in rather good
agreement with experiments, in contrast to the LDA and LDA+U description. For
$\alpha$-MnAs, we find a collinear ferromagnetic ground state in \qsgw, while
this phase is unstable in the LDA.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 01:57:14 GMT"
},
{
"version": "v2",
"created": "Sat, 5 Apr 2008 21:51:36 GMT"
}
] | 2008-07-08T00:00:00 | [
[
"Kotani",
"Takao",
""
],
[
"van Schilfgaarde",
"Mark",
""
]
] |
0707.3851 | Alexander Koldobsky | A.Koldobsky, H.K\"onig, M.Zymonopoulou | The complex Busemann-Petty problem on sections of convex bodies | 18 pages | null | null | null | math.FA math.MG | null | The complex Busemann-Petty problem asks whether origin symmetric convex
bodies in $\C^n$ with smaller central hyperplane sections necessarily have
smaller volume. We prove that the answer is affirmative if $n\le 3$ and
negative if $n\ge 4.$
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 02:29:58 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Koldobsky",
"A.",
""
],
[
"König",
"H.",
""
],
[
"Zymonopoulou",
"M.",
""
]
] |
0707.3852 | Jerome Le Ny | Jerome Le Ny, Eric Feron | Performance Evaluation of a Multi-Agent Risk-Sensitive Tracking System | 15 pages, 4 figures | null | null | null | math.OC | null | In this paper, we consider a simple linear exponential quadratic Gaussian
(LEQG) tracking problem for a multi-agent system. We study the dynamical
behaviors of the group as we vary the risk-sensitivity parameter, comparing in
particular the risk averse case to the LQG case. Then we consider the evolution
of the performance per agent as the number of agents in the system increases.
We provide some analytical as well as simulation results. In general, more
agents are beneficial only if noisy agent dynamics and/or imperfect
measurements are considered. The critical value of the risk sensitivity
parameter above which the cost becomes infinite increases with the number of
agents. In other words, for a fixed positive value of this parameter, there is
a minimum number of agents above which the cost remains finite.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 02:37:37 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Ny",
"Jerome Le",
""
],
[
"Feron",
"Eric",
""
]
] |
0707.3853 | Adam Rennie | Alan Carey, John Phillips, Adam Rennie | Semifinite spectral triples associated with graph C*-algebras | to appear in `Traces in Geometry, Number Theory and Quantum Fields',
published by Vieweg, eds S. Albeverio, M. Marcolli, | null | null | null | math.OA | null | We review the recent construction of semifinite spectral triples for graph
C^*-algebras. These examples have inspired many other developments and we
review some of these such as the relation between the semifinite index and the
Kasparov product, examples of noncommutative manifolds, and an index theorem in
twisted cyclic theory using a KMS state.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 02:41:55 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Carey",
"Alan",
""
],
[
"Phillips",
"John",
""
],
[
"Rennie",
"Adam",
""
]
] |
0707.3854 | Seung-il Nam | Ki-Seok Choi, Seung-il Nam, Atsushi Hosaka, Hyun-Chul Kim | eta photoproduction and N* resonances | 18 pages, 8 figures | J.Phys.G36:015008,2009 | 10.1088/0954-3899/36/1/015008 | PNU-NTG-07/2007, PNU-NuRI-07/2007, YITP-07-46, RCNP-Th07007,
INHA-NTG-04/2008 | hep-ph | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We investigate the eta photoproduction using the effective Lagrangian
approach at the tree level. We focus on the new nucleon resonance N*(1675),
which was reported by the GRAAL, CB-ELSA and Tohoku LNS, testing its possible
spin and parity states theoretically (J^P=1/2^+-,3/2^+-). In addition, we
include six nucleon resonances, D_13(1520), S_11(1535), S_11(1650), D_15(1675),
P_11(1710), P_13(1720) as well as the possible background contributions. We
calculate various cross sections including beam asymmetries for the neutron and
proton targets. We find noticeable isospin asymmetry in transition amplitudes
for photon and neutron targets. This observation may indicate that the new
resonance can be identified as a non-strangeness member of the baryon
antidecuplet.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 08:51:49 GMT"
},
{
"version": "v2",
"created": "Wed, 12 Mar 2008 05:05:08 GMT"
},
{
"version": "v3",
"created": "Wed, 30 Apr 2008 07:01:22 GMT"
},
{
"version": "v4",
"created": "Wed, 7 Jan 2009 00:55:29 GMT"
}
] | 2009-01-07T00:00:00 | [
[
"Choi",
"Ki-Seok",
""
],
[
"Nam",
"Seung-il",
""
],
[
"Hosaka",
"Atsushi",
""
],
[
"Kim",
"Hyun-Chul",
""
]
] |
0707.3855 | Han-Ying Guo | Han-Ying Guo | Special Relativity and Theory of Gravity via Maximum Symmetry and
Localization -- In Honor of the 80th Birthday of Professor Qikeng Lu | 39 pages. Invited talk at the 2006 International Conference on
Several Complex Variables, June 5 - 9, 2006; Beijing, China | Science in China A, Vol.51 [4] (2008) 568-603 | null | null | gr-qc | null | Like Euclid, Riemann and Lobachevsky geometries on an almost equal footing,
based on the principle of relativity of maximum symmetry proposed by Lu and the
postulate on invariant universal constants, dS/AdS SR can be set up on an
almost equal footing with Einstein's SR. For dS-case, there is a coin-like
relation: A law of inertia in Beltrami atlas with Beltrami time simultaneity
for the PoR on one side. The proper-time simultaneity and a RW-like dS-space
with entropy and an accelerated expanding S^3 fitting the cosmological
principle on another. If our universe is asymptotic to the RW-like dS-space, it
should be slightly closed with an entropy bound. Contrarily, via its asymptotic
behavior, it can fix on Beltrami frames without `an argument in a circle' and
acts as the origin of inertia. There is a triality of conformal extensions of
three kinds of SR and their null physics on the projective boundary of a 5-d
AdS-space. Thus there is a dS-spacetime on the boundary of a vacuum of
supergravity. Gravity should be based on the localized PoR of full maximum
symmetry with a gauge-like dynamics. Thus, this may lead to theory of gravity
of corresponding local maximum symmetry. A simple model of dS-gravity
characterized by a dimensionless constant shows the features. Our universe may
already indicate that the dS SR and the dS-gravity be the foundation of large
scale physics.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 03:43:36 GMT"
},
{
"version": "v2",
"created": "Sat, 15 Mar 2008 08:26:02 GMT"
}
] | 2008-03-15T00:00:00 | [
[
"Guo",
"Han-Ying",
""
]
] |
0707.3856 | Anna Amirdjanova | Anna Amirdjanova, Matthew Linn | Stochastic evolution equations for nonlinear filtering of random fields
in the presence of fractional Brownian sheet observation noise | 24 pages | null | null | null | math.PR | null | The problem of nonlinear filtering of a random field observed in the presence
of a noise, modeled by a persistent fractional Brownian sheet of Hurst index
$(H_1,H_2)$ with $0.5<H_1,H_2<1$, is studied and a suitable version of the
Bayes' formula for the optimal filter is obtained. Two types of spatial
"fractional" analogues of the Duncan-Mortensen-Zakai equation are also derived:
one tracks evolution of the unnormalized optimal filter along an arbitrary
"monotone increasing" (in the sense of partial ordering in $\mathbb{R}^2$)
one-dimensional curve in the plane, while the other describes dynamics of the
filter along the paths that are truly two-dimensional. Although the paper deals
with the two-dimensional parameter space, the presented approach and results
extend to $d$-parameter random fields with arbitrary $d\geq 3$.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 04:11:56 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Amirdjanova",
"Anna",
""
],
[
"Linn",
"Matthew",
""
]
] |
0707.3857 | Qiang-Hua Wang | Bin Cheng, Qiang-Hua Wang and Robert Joynt | Exact solution of a model of qubit dephasing due to telegraph noise | 7 pages, 6 figures, revised and extended | null | 10.1103/PhysRevA.78.022313 | null | quant-ph | null | We present a general and exact formalism for finding the evolution of a
quantum system subject to external telegraph noise. The various qubit
decoherence rates are determined by the eigenvalues of a transfer matrix. The
formalism can be applied to a qubit subject to an arbitrary combination of
dephasing and relaxational telegraph noise, in contrast to existing
non-perturbative methods that treat only one or the other of these limits. We
present 3 applications: 1) We obtain the full qubit dynamics on time scales
short compared with the enviromental correlation times. In the strong coupling
cases this reveals unexpected oscillations and induced magnetization
components; 2) We find in strong coupling case strong violations of the widely
used relation 1/T$_2$ = 1/2T$_1$ + 1/T$_{\phi}$, which is a result of
perturbation theory; 3) We discuss the effects of bang-bang and spin-echo
controls of the qubit dynamics in general settings of the telegraph noises.
%The result shows that these methods are not very effective in %reducing
decoherence arising from a single telegraph noise. Finally, we discuss the
extension of the method to the cases of many telegraph noise sources and
multiple qubits. The method still works when white noise is also present.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 04:38:04 GMT"
},
{
"version": "v2",
"created": "Tue, 13 May 2008 04:37:19 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Cheng",
"Bin",
""
],
[
"Wang",
"Qiang-Hua",
""
],
[
"Joynt",
"Robert",
""
]
] |
0707.3858 | Sachindeo Vaidya | Sachindeo Vaidya | The quantum sinh-Gordon model in noncommutative (1+1) dimensions | 7 pages, 2 figures, LaTex. References added | Phys.Lett.B655:294-297,2007 | 10.1016/j.physletb.2007.08.089 | IISc/CHEP/10/07 | hep-th | null | Using twisted commutation relations we show that the quantum sinh-Gordon
model on noncommutative space is integrable, and compute the exact two-particle
scattering matrix. The model possesses a strong-weak duality, just like its
commutative counterpart.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 05:56:10 GMT"
},
{
"version": "v2",
"created": "Mon, 6 Aug 2007 06:12:38 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Vaidya",
"Sachindeo",
""
]
] |
0707.3859 | Guy F. de T\'eramond | Stanley J. Brodsky and Guy F. de Teramond | Light-Front Dynamics and AdS/QCD Correspondence: The Pion Form Factor in
the Space- and Time-Like Regions | 21 pages, 7 figures. Title adjusted to PRD title. Typo corrected in
Eq (B3) | Phys.Rev.D77:056007,2008 | 10.1103/PhysRevD.77.056007 | SLAC-PUB 12544 | hep-ph hep-th | null | The AdS/CFT correspondence between string theory in AdS space and conformal
field theories in physical space-time leads to an analytic, semi-classical
model for strongly-coupled QCD which has scale invariance and dimensional
counting at short distances and color confinement at large distances. The
AdS/CFT correspondence also provides insights into the inherently
non-perturbative aspects of QCD such as the orbital and radial spectra of
hadrons and the form of hadronic wavefunctions. In particular, we show that
there is an exact correspondence between the fifth-dimensional coordinate of
anti-de Sitter (AdS) space $z$ and a specific light-front impact variable
$\zeta$ which measures the separation of the quark and gluonic constituents
within the hadron in ordinary space-time. This connection allows one to compute
the analytic form of the frame-independent light-front wavefunctions of mesons
and baryons, the fundamental entities which encode hadron properties and which
allow the computation of decay constants, form factors and other exclusive
scattering amplitudes. Relativistic light-front equations in ordinary
space-time are found which reproduce the results obtained using the
fifth-dimensional theory. As specific examples we compute the pion coupling
constant $f_\pi$, the pion charge radius $< r_\pi^2 >$ and examine the
propagation of the electromagnetic current in AdS space, which determines the
space and time-like behavior of the pion form factor and the pole of the $\rho$
meson.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 06:51:40 GMT"
},
{
"version": "v2",
"created": "Sat, 13 Oct 2007 08:43:54 GMT"
},
{
"version": "v3",
"created": "Tue, 11 Mar 2008 02:47:33 GMT"
},
{
"version": "v4",
"created": "Mon, 31 Mar 2008 16:32:40 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Brodsky",
"Stanley J.",
""
],
[
"de Teramond",
"Guy F.",
""
]
] |
0707.3860 | Christophe Leuridan | Jean Brossard, Christophe Leuridan | Cha\^{i}nes de Markov Constructives Index\'{e}es par Z | Published at http://dx.doi.org/10.1214/009117906000000430 in the
Annals of Probability (http://www.imstat.org/aop/) by the Institute of
Mathematical Statistics (http://www.imstat.org) | Annals of Probability 2007, Vol. 35, No. 2, 715-731 | 10.1214/009117906000000430 | IMS-AOP-AOP0174 | math.PR | null | Nous \'{e}tudions les cha\^{{\i}}nes de Markov $(X_n)_{n\in\mathbf{Z}}$
gouvern\'{e}es par une relation de r\'{e}currence de la forme
$X_{n+1}=f(X_n,V_{n+1})$, o\`{u} $(V_n)_{n\in\mathbf{Z}}$ est une suite de
variables al\'{e}atoires ind\'{e}pendantes et de m\^{e}me loi telle pour tout
$n\in \mathbf{Z}$, $V_{n+1}$ est ind\'{e}pendante de la suite
$((X_k,V_k))_{k\le n}$. L'objet de l'article est de donner une condition
n\'{e}cessaire et suffisante pour que les innovations $(V_n)_{n\in\mathbf{Z}}$
d\'{e}terminent compl\`{e}tement la suite $(X_n)_{n\in \mathbf{Z}}$ et de
d\'{e}crire l'information manquante dans le cas contraire.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 06:53:43 GMT"
}
] | 2009-09-29T00:00:00 | [
[
"Brossard",
"Jean",
""
],
[
"Leuridan",
"Christophe",
""
]
] |
0707.3861 | Tatiana Shulman | Tatiana Shulman | The C*-algebras qA\otimes K and S^2A\otimes K are asymptotically
equivalent | 12 pages | J. Operator Theory, Volume 63, Issue 1 (2010), pp. 85-100 | null | null | math.OA math.KT | null | Let $A$ be a separable $C^*$-algebra. We prove that its stabilized second
suspension $S^2A\otimes \mathcal K$ and the $C^*$-algebra $qA\otimes \mathcal
K$ constructed by Cuntz in the framework of his picture of KK-theory are
asymptotically equivalent. This means that there exist asymptotic morphisms
from each to the other whose compositions are homotopic to the identity maps.
This result yields an easy description of the natural transformation from
KK-theory to E-theory. One more corollary is the following. T. Loring ([3])
proved that any asymptotic morphism from $\qC$ to any $C^*$-algebra $B$ is
homotopic to a $\ast$-homomorphism. We prove that the same is true when $\C$ is
replaced by any nuclear $C^*$-algebra $A$ and when $B$ is stable.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 07:06:58 GMT"
},
{
"version": "v2",
"created": "Thu, 10 Jan 2008 08:17:33 GMT"
}
] | 2010-08-09T00:00:00 | [
[
"Shulman",
"Tatiana",
""
]
] |
0707.3862 | Victor H. Moll | Dante Manna and Victor H. Moll | Rational Landen transformations on the real line | 22 pages | null | 10.1090/S0025-5718-07-01954-0 | null | math.CA | null | The rational Landen transformation is a map on the space of coefficients of a
rational integrand that preserves the value of the integral. We provide a
family of these transformations that apply to rational integrands on the whole
line. Given an integer m, these transformations produce a numerical scheme to
evaluate the integral that is of order m.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 12:50:54 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Manna",
"Dante",
""
],
[
"Moll",
"Victor H.",
""
]
] |
0707.3863 | Mikhail Sodin | F. Nazarov, M. Sodin, A. Volberg | The Jancovici - Lebowitz - Manificat law for large fluctuations of
random complex zeroes | 34 pages, 1 figure | Comm. Math. Phys. 284 (2008), no. 3, 833-865 | null | null | math.PR math-ph math.CV math.MP | null | By random complex zeroes we mean the zero set of a random entire function
whose Taylor coefficients are independent complex-valued Gaussian variables,
and the variance of the k-th coefficient is 1/k!. This zero set is distribution
invariant with respect to isometries of the complex plane. We study large
fluctuations of random complex zeroes and show that they obey the asymptotic
law that was discovered some time ago by Jancovici, Lebowitz and Manificat for
charge fluctuations of a Coulomb system of particles.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 07:13:37 GMT"
},
{
"version": "v2",
"created": "Mon, 3 Sep 2007 19:55:30 GMT"
}
] | 2016-12-21T00:00:00 | [
[
"Nazarov",
"F.",
""
],
[
"Sodin",
"M.",
""
],
[
"Volberg",
"A.",
""
]
] |
0707.3864 | Bao-Xi Sun | Chang-Geng Liu and Bao-Xi Sun | The equation of state for the nuclear matter and the properties of the
neutron star | This article is based on Chang-Geng Liu's graduate thesis. 11 pages
and 4 figures | null | null | null | nucl-th | null | The equation of state for the beta stable nuclear matter is calculated
numerically, and then the Tolman-Oppenheimer-Volkov equation for the structure
of the neutron star is solved in the fourth-order Runge-Kutta algorithm. It
shows the mass and radius of the neutron star are functions of the central
density of the neutron star and a maximum mass of 1.932 solar masses with a
corresponding radius of 9.340km is obtained. Considering the equation of state
of the nuclear matter must obey the causality, a new factor c is added in the
nuclear potential energy formula. Therefore, with a new equation of state for
the beta stable nuclear matter when c=0.15, a new maximum mass of 1.440 solar
masses with a radius of 9.765km for the neutron star is obtained. Finally, the
contribution of the cosmological constant to the structure of the neutron star
is discussed, and we find the cosmological constant has minimal or negligible
influence on the properties of the neutron star.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 07:22:46 GMT"
},
{
"version": "v2",
"created": "Tue, 7 Aug 2007 13:37:59 GMT"
}
] | 2007-08-07T00:00:00 | [
[
"Liu",
"Chang-Geng",
""
],
[
"Sun",
"Bao-Xi",
""
]
] |
0707.3865 | Eli Barkai | Adi Rebenshtok, Eli Barkai | Distribution of Time-Averaged Observables for Weak Ergodicity Breaking | 5 pages, 2 figures | Phys. Rev. Letters 99, 210601 (2007) | 10.1103/PhysRevLett.99.210601 | null | cond-mat.stat-mech | null | We find a general formula for the distribution of time-averaged observables
for systems modeled according to the sub-diffusive continuous time random walk.
For Gaussian random walks coupled to a thermal bath we recover ergodicity and
Boltzmann's statistics, while for the anomalous subdiffusive case a weakly
non-ergodic statistical mechanical framework is constructed, which is based on
L\'evy's generalized central limit theorem. As an example we calculate the
distribution of $\bar{X}$: the time average of the position of the particle,
for unbiased and uniformly biased particles, and show that $\bar{X}$ exhibits
large fluctuations compared with the ensemble average $<X>$.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 07:23:49 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Rebenshtok",
"Adi",
""
],
[
"Barkai",
"Eli",
""
]
] |
0707.3866 | A. Deniz Sezer | A. Deniz Sezer | Filtration shrinkage by level-crossings of a diffusion | Published at http://dx.doi.org/10.1214/009117906000000683 in the
Annals of Probability (http://www.imstat.org/aop/) by the Institute of
Mathematical Statistics (http://www.imstat.org) | Annals of Probability 2007, Vol. 35, No. 2, 739-757 | 10.1214/009117906000000683 | IMS-AOP-AOP0188 | math.PR | null | We develop the mathematics of a filtration shrinkage model that has recently
been considered in the credit risk modeling literature. Given a finite
collection of points $x_1<...<x_N$ in $\mathbb{R}$, the region indicator
function $R(x)$ assumes the value $i$ if $x\in(x_{i-1},x_i]$. We take
$\mathbb{F}$ to be the filtration generated by $(R(X_t))_{t\geq0}$, where $X$
is a diffusion with infinitesimal generator $\mathcal{A}$. We prove a
martingale representation theorem for $\mathbb{F}$ in terms of stochastic
integrals with respect to $N$ random measures whose compensators have a simple
form given in terms of certain L\'{e}vy measures $F^{j\pm}_i$, which are
related to the differential equation $\mathcal{A}u=\lambda u$.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 07:25:03 GMT"
}
] | 2009-09-29T00:00:00 | [
[
"Sezer",
"A. Deniz",
""
]
] |
0707.3867 | Hiromitsu Takahashi | Hiromitsu Takahashi, Yasushi Fukazawa, Tsunefumi Mizuno, Ayumi
Hirasawa, Shunji Kitamoto, Keisuke Sudoh, Takayuki Ogita, Aya Kubota, Kazuo
Makishima, Takeshi Itoh, Arvind N. Parmar, Ken Ebisawa, Sachindra Naik,
Tadayasu Dotani, Motohide Kokubun, Kousuke Ohnuki, Tadayuki Takahashi, Tahir
Yaqoob, Lorella Angelini, Yoshihiro Ueda, Kazutaka Yamaoka, Taro Kotani,
Nobuyuki Kawai, Masaaki Namiki, Takayoshi Kohmura, Hitoshi Negoro | Low/Hard State Spectra of GRO J1655-40 Observed with Suzaku | 32 pages, 12 figures; accepted for publication in Publications of the
Astronomical Society of Japan (PASJ) | null | 10.1093/pasj/60.sp1.S69 | null | astro-ph | null | The Galactic black-hole binary GRO J1655$-$40 was observed with Suzaku on
2005 September 22--23, for a net exposure of 35 ks with the X-ray Imaging
Spectrometer (XIS) and 20 ks with the Hard X-ray Detector (HXD). The source was
detected over a broad and continuous energy range of 0.7--300 keV, with an
intensity of $\sim$50 mCrab at 20 keV. At a distance of 3.2 kpc, the 0.7--300
keV luminosity is $ \sim 5.1 \times 10^{36}$ erg s$^{-1}$ ($\sim 0.7$ % of the
Eddington luminosity for a 6 $M_{\odot}$ black hole). The source was in a
typical low/hard state, exhibiting a power-law shaped continuum with a photon
index of $\sim 1.6$. During the observation, the source intensity gradually
decreased by 25% at energies above $\sim 3$ keV, and by 35% below 2 keV. This,
together with the soft X-ray spectra taken with the XIS, suggests the presence
of an independent soft component that can be represented by emission from a
cool ($\sim 0.2$ keV) disk. The hard X-ray spectra obtained with the HXD reveal
a high-energy spectral cutoff, with an e-folding energy of $\sim 200$ keV.
Since the spectral photon index above 10 keV is harder by $\sim 0.4$ than that
observed in the softer energy band, and the e-folding energy is higher than
those of typical reflection humps, the entire 0.7--300 keV spectrum cannot be
reproduced by a single thermal Comptonization model, even considering
reflection effects. Instead, the spectrum (except the soft excess) can be
successfully explained by invoking two thermal-Comptonization components with
different $y$-parameters. In contrast to the high/soft state spectra of this
object in which narrow iron absorption lines are detected with equivalent
widths of 60--100 eV, the present XIS spectra bear no such features beyond an
upper-limit equivalent width of 25 eV.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 07:30:41 GMT"
}
] | 2017-01-18T00:00:00 | [
[
"Takahashi",
"Hiromitsu",
""
],
[
"Fukazawa",
"Yasushi",
""
],
[
"Mizuno",
"Tsunefumi",
""
],
[
"Hirasawa",
"Ayumi",
""
],
[
"Kitamoto",
"Shunji",
""
],
[
"Sudoh",
"Keisuke",
""
],
[
"Ogita",
"Takayuki",
""
],
[
"Kubota",
"Aya",
""
],
[
"Makishima",
"Kazuo",
""
],
[
"Itoh",
"Takeshi",
""
],
[
"Parmar",
"Arvind N.",
""
],
[
"Ebisawa",
"Ken",
""
],
[
"Naik",
"Sachindra",
""
],
[
"Dotani",
"Tadayasu",
""
],
[
"Kokubun",
"Motohide",
""
],
[
"Ohnuki",
"Kousuke",
""
],
[
"Takahashi",
"Tadayuki",
""
],
[
"Yaqoob",
"Tahir",
""
],
[
"Angelini",
"Lorella",
""
],
[
"Ueda",
"Yoshihiro",
""
],
[
"Yamaoka",
"Kazutaka",
""
],
[
"Kotani",
"Taro",
""
],
[
"Kawai",
"Nobuyuki",
""
],
[
"Namiki",
"Masaaki",
""
],
[
"Kohmura",
"Takayoshi",
""
],
[
"Negoro",
"Hitoshi",
""
]
] |
0707.3868 | Mohamad Ali Jafarizadeh | M. A. Jafarizadeh, M. Mirzaee, M. Rezaee | Finite quantum tomography via semidefinite programming | 25 pages | International Journal of Theoretical Physics, Vol. 46, No. 6, June
2007, page 1471 | 10.1007/s10773-006-9287-9 | null | quant-ph | null | Using the the convex semidefinite programming method and superoperator
formalism we obtain the finite quantum tomography of some mixed quantum states
such as: qudit tomography, N-qubit tomography, phase tomography and coherent
spin state tomography, where that obtained results are in agreement with those
of References \cite{schack,Pegg,Barnett,Buzek,Weigert}.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 07:37:12 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Jafarizadeh",
"M. A.",
""
],
[
"Mirzaee",
"M.",
""
],
[
"Rezaee",
"M.",
""
]
] |
0707.3869 | Steffen Mieske | Steffen Mieske, Michael Hilker, Leopoldo Infante, Claudia Mendes de
Oliveira | A flat faint end of the Fornax cluster galaxy luminosity function | 5 pages, 4 figures, to appear in the proceedings of IAU Symposium 244
'Dark galaxies and lost baryons', Cambridge University Press, editors J. I.
Davies & M. D. Disney | null | 10.1017/S1743921307014172 | null | astro-ph | null | We analyse the photometric properties of the early-type Fornax cluster dwarf
galaxy population (M_V>-17 mag), based on a wide field imaging study of the
central cluster area in V and I band-passes with IMACS/Magellan at Las Campanas
Observatory. We create a fiducial sample of ~100 Fornax cluster dwarf
ellipticals (dEs) with -16.6<M_V<-8.8 mag in the following three steps: (1) To
verify cluster membership, we measured I-band surface brightness fluctuations
(SBF) distances to candidate dEs known from previous surveys; (2) We
re-assessed morphological classifications for those candidate dEs that are too
faint for SBF detection; and (3) We searched for new candidate dEs in the
size-luminosity regime close to the resolution limit of previous surveys. The
resulting fiducial dE sample follows a well-defined surface brightness -
magnitude relation, showing that Fornax dEs are about 40% larger than Local
Group dEs. The sample also defines a colour-magnitude relation similar to that
of Local Group dEs. The early-type dwarf galaxy luminosity function in Fornax
has a very flat faint end slope alpha = -1.1 +/- 0.1. We compare the number of
dwarfs per unit mass with those in other environments and find that the Fornax
cluster fits well into a general trend of a lack of high-mass dwarfs in more
massive environments.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 07:38:17 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Mieske",
"Steffen",
""
],
[
"Hilker",
"Michael",
""
],
[
"Infante",
"Leopoldo",
""
],
[
"de Oliveira",
"Claudia Mendes",
""
]
] |
0707.3870 | Sintayehu Tesfa Woldemariam Mr | Sintayehu Tesfa | Spontaneously induced atom-radiation entanglement in an ensemble of
two-level atoms | 7 pages, 3 figures | null | 10.1080/09500340701739571 | null | quant-ph | null | Analysis of the spontaneously induced correlation on atom-radiation
entanglement in an ensemble of two-level atoms initially prepared in the upper
level and placed in a cavity containing a squeezed radiation employing the
method of evaluating the coherent-state propagator is presented. It is found
that the cavity radiation exhibits squeezing which is directly attributed to
the squeezed radiation in the cavity. The intensity of the cavity radiation
increases with the squeeze parameter and interaction time. It is also shown
that substantial degree of entanglement between the atomic states and radiation
mode exits at a particular time that depends on the coupling constant and
squeeze parameter. We come to understand that though the squeezed radiation is
directly accountable for the cavity squeezing, it significantly destroys the
atom-radiation entanglement.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 07:45:28 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Tesfa",
"Sintayehu",
""
]
] |
0707.3871 | Alexey Gavrilov | A. V. Gavrilov | On the Clausius theorem | null | null | null | null | physics.gen-ph | null | We show that for a metastable system there exists a theoretical possibility
of a violation of the Clausius inequality without a violation of the second
law. Possibilities of experimental detection of this hypothetical violation are
pointed out.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 07:53:23 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Gavrilov",
"A. V.",
""
]
] |
0707.3872 | Sagawa Takahiro | Takahiro Sagawa, Masahito Ueda | Accuracy matrix in generalized simultaneous measurement of a qubit
system | null | Phys. Rev. A 77, 012313 (2008) | 10.1103/PhysRevA.77.012313 | null | quant-ph | null | We formulate the accuracy of quantum measurement for a qubit system in terms
of a 3 by 3 matrix. This matrix, which we refer to as the accuracy matrix, can
be calculated from a positive operator-valued measure (POVM) corresponding to
the quantum measurement. Based on the accuracy matrix, we derive new trade-off
relations between the measurement accuracy of two or three noncommuting
observables of a qubit system. These trade-off relations offer a quantitative
information-theoretic representation of Bohr's principle of complementarity.
They can be interpreted as the uncertainty relations between measurement errors
in simultaneous measurements, and also as the trade-off relations between the
measurement error and back-action of measurement. A no-cloning inequality is
derived from the trade-off relations. Furthermore, our formulation and the
obtained results can be applied to analyze quantum state tomography. We also
show that the accuracy matrix is closely related to the maximum-likelihood
estimation and the Fisher information matrix for a finite number of samples;
the accuracy matrix tells us how accurately we can estimate the probability
distributions of observables of an unknown state by quantum measurement.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 07:56:11 GMT"
},
{
"version": "v2",
"created": "Mon, 5 Nov 2007 07:50:15 GMT"
},
{
"version": "v3",
"created": "Thu, 17 Jan 2008 09:03:01 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Sagawa",
"Takahiro",
""
],
[
"Ueda",
"Masahito",
""
]
] |
0707.3873 | Guido Consonni | Guido Consonni, H\'el\`ene Massam | Alternative parametrizations and reference priors for decomposable
discrete graphical models | 31 pages, 2 figures | null | null | null | math.ST stat.TH | null | For a given discrete decomposable graphical model, we identify several
alternative parametrizations, and construct the corresponding reference priors
for suitable groupings of the parameters. Specifically, assuming that the
cliques of the graph are arranged in a perfect order, the parameters we
consider are conditional probabilities of clique-residuals given separators, as
well as generalized log-odds-ratios. We also consider a parametrization
associated to a collection of variables representing a cut for the statistical
model. The reference priors we obtain do not depend on the order of the
groupings, belong to a conjugate family, and are proper.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 09:51:25 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Consonni",
"Guido",
""
],
[
"Massam",
"Hélène",
""
]
] |
0707.3874 | Kevin Stratford | K. Stratford, J.-C. Desplat, P. Stansell, M. E. Cates | Binary fluids under steady shear in three dimensions | 4 pages, 3 figures | null | 10.1103/PhysRevE.76.030501 | null | cond-mat.stat-mech | null | We simulate by lattice Boltzmann the steady shearing of a binary fluid
mixture with full hydrodynamics in three dimensions. Contrary to some
theoretical scenarios, a dynamical steady state is attained with finite
correlation lengths in all three spatial directions. Using large simulations we
obtain at moderately high Reynolds numbers apparent scaling expon ents
comparable to those found by us previously in 2D. However, in 3D there may be a
crossover to different behavior at low Reynolds number: accessing this regime
requires even larger computational resource than used here.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 08:30:28 GMT"
},
{
"version": "v2",
"created": "Fri, 14 Sep 2007 18:06:03 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Stratford",
"K.",
""
],
[
"Desplat",
"J. -C.",
""
],
[
"Stansell",
"P.",
""
],
[
"Cates",
"M. E.",
""
]
] |
0707.3875 | Vittorio Cataudella | G. De Filippis, V. Cataudella, A. S. Mishchenko and N. Nagaosa | Non-local composite spin-lattice polarons in high temperature
superconductors | 5 pages, 4 figures | Phys. Rev. Lett. 99, 146405 (2007) | 10.1103/PhysRevLett.99.146405 | null | cond-mat.str-el cond-mat.supr-con | null | The non-local nature of the polaron formation in t-t'-t"-J model is studied
in large lattices up to 64 sites by developing a new numerical method. We show
that the effect of longer-range hoppings t' and t" is a large anisotropy of the
electron-phonon interaction (EPI) leading to a completely different influence
of EPI on the nodal and antinodal points in agreement with the experiments.
Furthermore, nonlocal EPI preserves polaron's quantum motion, which destroys
the antiferromagnetic order effectively, even at strong coupling regime,
although the quasi-particle weight in angle-resolved-photoemission spectroscopy
is strongly suppressed.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 08:36:46 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"De Filippis",
"G.",
""
],
[
"Cataudella",
"V.",
""
],
[
"Mishchenko",
"A. S.",
""
],
[
"Nagaosa",
"N.",
""
]
] |
0707.3876 | Branko Dragovich | Branko Dragovich | Adeles in Mathematical Physics | 9 pages. Invited talk at the international conference Actual Problems
of Mathematics and Computer Modeling, 18-22 June 2007, Grodno, Belarus. To
appear in the Proceedings | null | null | null | math-ph hep-th math.MP | null | Application of adeles in modern mathematical physics is briefly reviewed. In
particular, some adelic products are presented.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 08:41:29 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Dragovich",
"Branko",
""
]
] |
0707.3877 | Guido Consonni | Guido Consonni, Luca La Rocca | Intrinsic tests for the equality of two correlated proportions | 31 pages, 6 figures | null | null | null | math.ST stat.TH | null | Correlated proportions arise in longitudinal (panel) studies. A typical
example is the ``opinion swing'' problem: ``Has the proportion of people
favoring a politician changed after his recent speech to the nation on TV?''.
Since the same group of individuals is interviewed before and after the speech,
the two proportions are correlated. A natural null hypothesis to be tested is
whether the corresponding population proportions are equal. A standard Bayesian
approach to this problem has already been considered in the literature, based
on a Dirichlet prior for the cell-probabilities of the underlying two-by-two
table under the alternative hypothesis, together with an induced prior under
the null. In lack of specific prior information, a diffuse (e.g. uniform)
distribution may be used. We claim that this approach is not satisfactory,
since in a testing problem one should make sure that the prior under the
alternative be adequately centered around the region specified by the null, in
order to obtain a fair comparison between the two hypotheses. Following an
intrinsic prior methodology, we develop two strategies for the construction of
a collection of objective priors increasingly peaked around the null. We
provide a simple interpretation of their structure in terms of weighted
imaginary sample scenarios. We illustrate our method by means of three
examples, carrying out sensitivity analysis and providing comparison with
existing results.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 08:41:39 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Consonni",
"Guido",
""
],
[
"La Rocca",
"Luca",
""
]
] |
0707.3878 | Joaquim Borges | Joaquim Borges, Cristina Fernandez | Plotkin construction: rank and kernel | null | null | null | null | cs.IT math.IT | null | Given two binary codes of length n, using Plotkin construction we obtain a
code of length 2n. The construction works for linear and nonlinear codes. For
the linear case, it is straightforward to see that the dimension of the final
code is the sum of the dimensions of the starting codes. For nonlinear codes,
the rank and the dimension of the kernel are standard mesures of linearity. In
this report, we prove that both parameters are also the sum of the
corresponding ones of the starting codes.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 08:44:05 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Borges",
"Joaquim",
""
],
[
"Fernandez",
"Cristina",
""
]
] |
0707.3879 | Ingrid Kraus | I. Kraus, J. Cleymans, H. Oeschler, K. Redlich and S. Wheaton | Chemical Equilibrium in Collisions of Small Systems | 9 pages, 8 figures, submitted to Physical Review C | Phys.Rev.C76:064903,2007 | 10.1103/PhysRevC.76.064903 | null | hep-ph | null | The system-size dependence of particle production in heavy-ion collisions at
the top SPS energy is analyzed in terms of the statistical model. A systematic
comparison is made of two suppression mechanisms that quantify strange particle
yields in ultra-relativistic heavy-ion collisions: the canonical model with
strangeness correlation radius determined from the data and the model
formulated in the canonical ensemble using chemical off-equilibrium strangeness
suppression factor. The system-size dependence of the correlation radius and
the thermal parameters are obtained for p-p, C-C, Si-Si and Pb-Pb collisions at
sqrt(s_NN) = 17.3 AGeV. It is shown that on the basis of a consistent set of
data there is no clear difference between the two suppression patterns. In the
present study the strangeness correlation radius was found to exhibit a rather
weak dependence on the system size.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 08:57:17 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Kraus",
"I.",
""
],
[
"Cleymans",
"J.",
""
],
[
"Oeschler",
"H.",
""
],
[
"Redlich",
"K.",
""
],
[
"Wheaton",
"S.",
""
]
] |
0707.3880 | Michel Brune | Christine Guerlin (LKB - Lhomond), Julien Bernu (LKB - Lhomond),
Samuel Del\'eglise (LKB - Lhomond), Cl\'ement Sayrin (LKB - Lhomond),
S\'ebastien Gleyzes (LKB - Lhomond), Stefan Kuhr (LKB - Lhomond), Michel
Brune (LKB - Lhomond), Jean-Michel Raimond (LKB - Lhomond), Serge Haroche
(LKB - Lhomond) | Progressive field-state collapse and quantum non-demolition photon
counting | null | Nature 448, 23 (2007) 889 | 10.1038/nature06057 | null | quant-ph | null | The irreversible evolution of a microscopic system under measurement is a
central feature of quantum theory. From an initial state generally exhibiting
quantum uncertainty in the measured observable, the system is projected into a
state in which this observable becomes precisely known. Its value is random,
with a probability determined by the initial system's state. The evolution
induced by measurement (known as 'state collapse') can be progressive,
accumulating the effects of elementary state changes. Here we report the
observation of such a step-by-step collapse by measuring non-destructively the
photon number of a field stored in a cavity. Atoms behaving as microscopic
clocks cross the cavity successively. By measuring the light-induced
alterations of the clock rate, information is progressively extracted, until
the initially uncertain photon number converges to an integer. The suppression
of the photon number spread is demonstrated by correlations between repeated
measurements. The procedure illustrates all the postulates of quantum
measurement (state collapse, statistical results and repeatability) and should
facilitate studies of non-classical fields trapped in cavities.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 19:03:50 GMT"
}
] | 2008-03-13T00:00:00 | [
[
"Guerlin",
"Christine",
"",
"LKB - Lhomond"
],
[
"Bernu",
"Julien",
"",
"LKB - Lhomond"
],
[
"Deléglise",
"Samuel",
"",
"LKB - Lhomond"
],
[
"Sayrin",
"Clément",
"",
"LKB - Lhomond"
],
[
"Gleyzes",
"Sébastien",
"",
"LKB - Lhomond"
],
[
"Kuhr",
"Stefan",
"",
"LKB - Lhomond"
],
[
"Brune",
"Michel",
"",
"LKB - Lhomond"
],
[
"Raimond",
"Jean-Michel",
"",
"LKB - Lhomond"
],
[
"Haroche",
"Serge",
"",
"LKB - Lhomond"
]
] |
0707.3881 | Cristiana Bertolin | Cristiana Bertolin | Some tensor products | This paper has been withdrawn by the author because it is a section
of the paper "Multilinear morphisms between 1-motives" | null | null | null | math.AG math.NT | null | We define the tensor product of 1-motives with motives of weight 0 and we
construct explicitely the 1-motive underlying the quotient M_1 \otimes M_2 /
W_{-3}(M_1 \otimes M_2).
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 08:58:48 GMT"
},
{
"version": "v2",
"created": "Thu, 22 Jul 2010 12:46:43 GMT"
}
] | 2010-07-23T00:00:00 | [
[
"Bertolin",
"Cristiana",
""
]
] |
0707.3882 | W. Son | Dagomir Kaszlikowski, Wonmin Son, Vlatko Vedral | Dimensionality induced entanglement in macroscopic dimer systems | 4 pages, 2 figures | Phys. Rev. A 76, 054302 (2007) | 10.1103/PhysRevA.76.054302 | null | quant-ph | null | We investigate entanglement properties of mixtures of short-range spin-s
dimer coverings in lattices of arbitrary topology and dimension. We show that
in one spacial dimension nearest neighbour entanglement exists for any spin
$s$. Surprisingly, in higher spatial dimensions there is a threshold value of
spin $s$ below which the nearest neighbour entanglement disappears. The
traditional "classical" limit of large spin value corresponds to the highest
nearest neighbour entanglement that we quantify using the negativity.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 09:02:57 GMT"
}
] | 2008-10-21T00:00:00 | [
[
"Kaszlikowski",
"Dagomir",
""
],
[
"Son",
"Wonmin",
""
],
[
"Vedral",
"Vlatko",
""
]
] |
0707.3883 | I.K. Gopalakrishnan | O. D. Jayakumar, I. K. Gopalakrishnan, A. Vinu, A. Asthana and A. K.
Tyagi | Room temperature Ferromagnetism in Th1-xFexO2-d (x = 0.0, 0.05, 0.10,
0.15, 0.20 and 0.25) nanoparticles | 10 pages, 5 figures | null | null | null | cond-mat.mtrl-sci | null | Nanocrystalline (Th1-xFex)O2-d particles with different Fe concentrations (x
= 0.0, 0.05, 0.10, 0.15, 0.20 and 0.25) have been prepared by a gel combustion
method. Rietveld refinement analyses of X-ray diffraction data revealed the
formation of an impurity free cubic type Th1-xFexO2-d structure up to x = 0.20.
This observation is further confirmed from the detailed studies conducted on 10
at. percent Fe doped ThO2 using high-resolution transmission electron
microscopy (HRTEM) imaging and indexing of the selected-area electron
diffraction (SAED) patterns. DC Magnetization studies as a function field
indicate that they are ferromagnetic with Curie temperature (Tc) well above
room temperature.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 09:07:18 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Jayakumar",
"O. D.",
""
],
[
"Gopalakrishnan",
"I. K.",
""
],
[
"Vinu",
"A.",
""
],
[
"Asthana",
"A.",
""
],
[
"Tyagi",
"A. K.",
""
]
] |
0707.3884 | Philip Smith | P. D. Smith (1), D. Tsiklauri (1), M. S. Ruderman (2) ((1) University
of Salford, England, (2) University of Sheffield, England) | Enhanced phase mixing of Alfv\'en waves propagating in stratified and
divergent coronal structures | Accepted by A&A - 24th September 2007 | A&A 475 3 (2007) 1111-1123 | 10.1051/0004-6361:20078218 | null | astro-ph | null | Corrected analytical solutions describing the enhanced phase mixing of Alfven
waves propagating in divergent stratified coronal structures are presented.
These show that the enhanced phase mixing mechanism can dissipate Alfven waves
at heights less than half that is predicted by the previous analytical
solutions. The enhanced phase mixing of 0.1 Hz harmonic Alfven waves
propagating in strongly divergent, H_b=5 Mm, stratified coronal structures,
H_rho=50 Mm, can fulfill 100% of an active region heating requirement, by
generating viscous heating fluxes of F_H~2100 J /m^2 /s. The Alfven waves in
this configuration are fully dissipated within 20 Mm, which is six times lower
than would occur as a result of standard phase mixing in uniform magnetic
fields. This results in the heating scale height, s_H, being lowered by a
factor of six, to less than half of an active regions density scale height.
Using the corrected analytical solutions it was found that, for a given wave
frequency, the generation of a heating scale height of s_H<=50 Mm, by enhanced
phase mixing in strongly divergent magnetic fields, requires a shear viscosity
eight orders of magnitude lower, than required by standard phase mixing in
uniform magnetic fields. It was also found that the enhanced phase mixing of
observable, 0.01 rads /s Alfven waves, in strongly divergent magnetic fields,
H_b=5 Mm, can generate heating scale heights within a density scale height,
H_rho=50 Mm, using classical Braginskii viscosity. It is therefore not
necessary to invoke anomalous viscosity in corona, if phase mixing takes place
in strongly divergent magnetic fields. This study shows that the importance of
enhanced phase mixing as a mechanism for dissipating Alfven waves in the solar
corona (a stratified and divergent medium), has been seriously underestimated.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 09:23:06 GMT"
},
{
"version": "v2",
"created": "Thu, 22 Nov 2007 08:02:40 GMT"
}
] | 2007-11-22T00:00:00 | [
[
"Smith",
"P. D.",
""
],
[
"Tsiklauri",
"D.",
""
],
[
"Ruderman",
"M. S.",
""
]
] |
0707.3885 | Frank Ferrari | Frank Ferrari (U.L. Bruxelles and Intl. Solvay Inst.) | Microscopic quantum superpotential in N=1 gauge theories | 23 pages, 1 figure; typos corrected, version to appear in JHEP | JHEP0710:065,2007 | 10.1088/1126-6708/2007/10/065 | LPTENS-07/33 | hep-th | null | We consider the N=1 super Yang-Mills theory with gauge group U(N), adjoint
chiral multiplet X and tree-level superpotential Tr W(X). We compute the
quantum effective superpotential W_mic as a function of arbitrary off-shell
boundary conditions at infinity for the scalar field X. This effective
superpotential has a remarkable property: its critical points are in one-to-one
correspondence with the full set of quantum vacua of the theory, providing in
particular a unified picture of solutions with different ranks for the low
energy gauge group. In this sense, W_mic is a good microscopic effective
quantum superpotential for the theory. This property is not shared by other
quantum effective superpotentials commonly used in the literature, like in the
strong coupling approach or the glueball superpotentials. The result of this
paper is a first step in extending Nekrasov's microscopic derivation of the
Seiberg-Witten solution of N=2 super Yang-Mills theories to the realm of N=1
gauge theories.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 09:46:04 GMT"
},
{
"version": "v2",
"created": "Thu, 25 Oct 2007 14:00:58 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Ferrari",
"Frank",
"",
"U.L. Bruxelles and Intl. Solvay Inst."
]
] |
0707.3886 | Ming Yang | Ming Yang | The growth of additive processes | Published at http://dx.doi.org/10.1214/009117906000000593 in the
Annals of Probability (http://www.imstat.org/aop/) by the Institute of
Mathematical Statistics (http://www.imstat.org) | Annals of Probability 2007, Vol. 35, No. 2, 773-805 | 10.1214/009117906000000593 | IMS-AOP-AOP0178 | math.PR | null | Let $X_t$ be any additive process in $\mathbb{R}^d.$ There are finite indices
$\delta_i, \beta_i, i=1,2$ and a function $u$, all of which are defined in
terms of the characteristics of $X_t$, such that
\liminf_{t\to0}u(t)^{-1/\eta}X_t^*= \cases{0, \quad if $\eta>\delta_1$,
\cr\infty, \quad if $\eta<\delta_2$,}
\limsup_{t\to0}u(t)^{-1/\eta}X_t^*= \cases{0, \quad if $\eta>\beta_2$,
\cr\infty, \quad if $\eta<\beta_1$,}\qquad {a.s.},
where $X_t^*=\sup_{0\le s\le t}|X_s|.$ When $X_t$ is a L\'{e}vy process with
$X_0=0$, $\delta_1=\delta_2$, $\beta_1=\beta_2$ and $u(t)=t.$ This is a special
case obtained by Pruitt. When $X_t$ is not a L\'{e}vy process, its
characteristics are complicated functions of $t$. However, there are
interesting conditions under which $u$ becomes sharp to achieve
$\delta_1=\delta_2$, $\beta_1=\beta_2.$
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 09:41:54 GMT"
}
] | 2011-11-10T00:00:00 | [
[
"Yang",
"Ming",
""
]
] |
0707.3887 | Pilar Hernandez | F. Bernardoni, P. Hern\'andez | Finite-size scaling for the left-current correlator with non-degenerate
quark masses | 27 pages, 4 figures | JHEP 0710:033,2007 | 10.1088/1126-6708/2007/10/033 | IFIC/07-34, FTUV-07-0727 | hep-lat | null | We study the volume dependence of the left-current correlator with
non-degenerate quark masses to next-to-leading order in the chiral expansion.
We consider three possible regimes: all quark masses are in the
$\epsilon$-regime, all are in the $p$-regime and a mixed-regime where the
lighest quark masses satisfy $m_v \Sigma V \leq 1$ while the heavier $m_s
\Sigma V \gg 1$. These results can be used to match lattice QCD and the Chiral
Effective Theory in a large but finite box in which the Compton wavelength of
the lightest pions is of the order of the box size. We consider both the full
and partially-quenched results.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 15:30:01 GMT"
}
] | 2010-02-03T00:00:00 | [
[
"Bernardoni",
"F.",
""
],
[
"Hernández",
"P.",
""
]
] |
0707.3888 | Ariel Yadin | Itai Benjamini, Ariel Yadin, Ofer Zeitouni | Maximal Arithmetic Progressions in Random Subsets | Slight errors in the constants corrected | Electronic Communications in Probability 12 (2007), 365-376 | null | null | math.PR math.CO | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Let U(N) denote the maximal length of arithmetic progressions in a random
uniform subset of {0,1}^N. By an application of the Chen-Stein method, we show
that U(N)- 2 log(N)/log(2) converges in law to an extreme type (asymmetric)
distribution. The same result holds for the maximal length W(N) of arithmetic
progressions (mod N). When considered in the natural way on a common
probability space, we observe that U(N)/log(N) converges almost surely to
2/log(2), while W(N)/log(N) does not converge almost surely (and in particular,
limsup W(N)/log(N) is at least 3/log(2)).
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 10:03:28 GMT"
},
{
"version": "v2",
"created": "Mon, 21 May 2012 10:12:30 GMT"
}
] | 2012-05-22T00:00:00 | [
[
"Benjamini",
"Itai",
""
],
[
"Yadin",
"Ariel",
""
],
[
"Zeitouni",
"Ofer",
""
]
] |
0707.3889 | Stephane Toulin | Yves Garrabos (ICMCB), Carole Lecoutre-Chabot (ICMCB), Fabien Palencia
(ICMCB) | Analytic application of the mean crossover function to the description
of the isothermal compressibility of xenon | null | null | null | null | cond-mat.stat-mech | null | We use the mean crossover functions [Garrabos and Bervillier, Phys Rev. E 74,
021113 (2006)] estimated from the bounded results of the Massive
Renormalization scheme applied to the $\Phi_{d}^{4}(n)$ model in three
dimensions ($d=3$) and scalar order parameter ($n=1$) [Bagnuls and Bervillier,
Phys. Rev. E 65, 066132 (2002)], to represent the singular behavior of the
isothermal compressibility of xenon along the critical isochore in the
homogeneous preasymptotic domain. The validity range and the Ising nature of
the crossover description are discussed in terms of a single scale factor whose
value can be analytically estimated beyond the Ising-like preasymptotic domain.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 10:05:11 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Garrabos",
"Yves",
"",
"ICMCB"
],
[
"Lecoutre-Chabot",
"Carole",
"",
"ICMCB"
],
[
"Palencia",
"Fabien",
"",
"ICMCB"
]
] |
0707.3890 | Christophe Texier | M. Ferrier, A. C. H. Rowe, S. Gueron, H. Bouchiat, C. Texier and G.
Montambaux | Geometrical dependence of decoherence by electronic interactions in a
GaAs/GaAlAs square network | LaTeX, 5 pages, 4 eps figures | Phys. Rev. Lett. 100, 146802 (2008) | 10.1103/PhysRevLett.100.146802 | null | cond-mat.mes-hall cond-mat.dis-nn | null | We investigate weak localization in metallic networks etched in a two
dimensional electron gas between $25\:$mK and $750\:$mK when electron-electron
(e-e) interaction is the dominant phase breaking mechanism. We show that, at
the highest temperatures, the contributions arising from trajectories that wind
around the rings and trajectories that do not are governed by two different
length scales. This is achieved by analyzing separately the envelope and the
oscillating part of the magnetoconductance. For $T\gtrsim0.3\:$K we find
$\Lphi^\mathrm{env}\propto{T}^{-1/3}$ for the envelope, and
$\Lphi^\mathrm{osc}\propto{T}^{-1/2}$ for the oscillations, in agreement with
the prediction for a single ring \cite{LudMir04,TexMon05}. This is the first
experimental confirmation of the geometry dependence of decoherence due to e-e
interaction.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 10:12:09 GMT"
},
{
"version": "v2",
"created": "Wed, 9 Apr 2008 15:18:32 GMT"
}
] | 2008-04-09T00:00:00 | [
[
"Ferrier",
"M.",
""
],
[
"Rowe",
"A. C. H.",
""
],
[
"Gueron",
"S.",
""
],
[
"Bouchiat",
"H.",
""
],
[
"Texier",
"C.",
""
],
[
"Montambaux",
"G.",
""
]
] |
0707.3891 | Naoum Karchev Prof. | Vasil Michev and Naoum Karchev | Curie temperature of the two band double exchange model for manganites | 14 pages, 9 figures | Physical Review B 76, 174412 (2008) | 10.1103/PhysRevB.76.174412 | null | cond-mat.str-el | null | We consider two-band double exchange model and calculate the critical
temperature in ferromagnetic regime (Curie temperature). The localized spins
are represented in terms of the Schwinger-bosons, and two spin-singlet Fermion
operators are introduced. In terms of the new Fermi fields the on-site Hund's
interactions are in a diagonal form and one accounts for them exactly.
Integrating out the spin-singlet fermions we derive an effective Heisenberg
type model for a vector which describes the local orientations of the total
magnetization. The transversal fluctuations of the vector are the true magnons
in the theory, which is a base for Curie temperature calculation. The critical
temperature is calculated employing the Schwinger-bosons mean-field theory.
While approximate, this technic of calculation captures the essentials of the
magnon fluctuations in the theory, and for 2D systems one obtains zero Curie
temperature, in accordance with Mermin-Wagner theorem.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 10:15:41 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Michev",
"Vasil",
""
],
[
"Karchev",
"Naoum",
""
]
] |
0707.3892 | Vladimir Nazaikinskii | V. E. Nazaikinskii, A. Yu. Savin, B. Yu. Sternin | On elliptic differential operators with shifts: II. The cohomological
index formula | 9 pages | null | null | null | math.OA math.AP math.KT | null | This paper is a continuation of arXiv:0706.3511, where we obtained a local
index formula for matrix elliptic operators with shifts. Here we establish a
cohomological index formula of Atiyah-Singer type for elliptic differential
operators with shifts acting between section spaces of arbitrary vector
bundles. The key step is the construction of closed graded traces on certain
differential algebras over the symbol algebra for this class of operators.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 10:23:40 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Nazaikinskii",
"V. E.",
""
],
[
"Savin",
"A. Yu.",
""
],
[
"Sternin",
"B. Yu.",
""
]
] |
0707.3893 | Massimo Mannarelli | Massimo Mannarelli and Cristina Manuel | Jet-induced gauge field instabilities in the quark-gluon plasma: A
kinetic theory approach | 13 pages, 6 figures | Phys.Rev.D77:054018,2008 | 10.1103/PhysRevD.77.054018 | null | hep-ph | null | We discuss the properties of the collective modes of a system composed by a
thermalized quark-gluon plasma traversed by a relativistic jet of partons. The
transport equations obeyed by the components of the plasma and of the jet are
studied in the Vlasov approximation. Assuming that the partons in the jet can
be described with a tsunami-like distribution function we derive the
expressions of the dispersion law of the collective modes. Then the behavior of
the unstable gauge modes of the system is analyzed for various values of the
velocity of the jet, of the momentum of the collective modes and of the angle
between these two quantities. We find that the most unstable modes are those
with momentum orthogonal to the velocity of the jet and that these
instabilities appear when the velocity of the jet is higher than a threshold
value, which depends on the plasma and jet frequencies. The results obtained
within the Vlasov approximation are compared with the corresponding results
obtained using a chromohydrodynamical approach.The effect we discuss here
suggests a possible collective mechanism for the description of the jet
quenching phenomena in heavy ion collisions.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 10:35:15 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Mannarelli",
"Massimo",
""
],
[
"Manuel",
"Cristina",
""
]
] |
0707.3894 | Harish Seshadri | Harish Seshadri | Manifolds with nonnegative isotropic curvature | 12 Pages | Communications in Analysis and Geometry 17 (2009), no. 4, 621-635 | null | null | math.DG | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We prove that if $(M^n,g)$, $n \ge 4$, is a compact, orientable, locally
irreducible Riemannian manifold with nonnegative isotropic curvature, then one
of the following possibilities hold:
(i) $M$ admits a metric with positive isotropic curvature
(ii) $(M,g)$ is isometric to a locally symmetric space
(iii) $(M,g)$ is K\"ahler and biholomorphic to $\C P^\frac {n}{2}$.
(iv) $(M,g)$ is quaternionic-K\"ahler.
This is implied by the following result:
Let $(M^{2n},g)$ be a compact, locally irreducible K\"ahler manifold with
nonnegative isotropic curvature. Then either $M$ is biholomorphic to $\C P^n$
or isometric to a compact Hermitian symmetric space. This answers a question of
Micallef and Wang in the affirmative.
The proof is based on the recent work of S. Brendle and R. Schoen on the
Ricci flow.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 10:43:21 GMT"
},
{
"version": "v2",
"created": "Mon, 17 Sep 2007 04:15:21 GMT"
},
{
"version": "v3",
"created": "Wed, 14 May 2008 17:29:35 GMT"
},
{
"version": "v4",
"created": "Fri, 8 Apr 2011 10:50:49 GMT"
}
] | 2011-04-11T00:00:00 | [
[
"Seshadri",
"Harish",
""
]
] |
0707.3895 | Michael Eisermann | Michael Eisermann | Knot colouring polynomials | 24 pages, 6 figures | Pacific Journal of Mathematics 231 (2007), no. 2, 305-336 | null | null | math.GT | null | This article introduces a natural extension of colouring numbers of knots,
called colouring polynomials, and studies their relationship to Yang-Baxter
invariants and quandle 2-cocycle invariants.
For a knot K in the 3-sphere let \pi_K be the fundamental group of the knot
complement, and let (m_K,l_K) be a meridian-longitude pair in \pi_K. Given a
finite group G and an element x in G, we consider the set of representations
\rho from \pi_K to G that map the meridian m_K to x, and define the colouring
polynomial P(K) as the sum over all longitude images \rho(l_K). The resulting
invariant maps knots to the group ring Z[G]. It is multiplicative with respect
to connected sum and equivariant with respect to symmetry operations of knots.
Examples are given to show that colouring polynomials distinguish knots for
which other invariants fail, in particular they can distinguish knots from
their mutants, obverses, inverses, or reverses.
We prove that every quandle 2-cocycle state-sum invariant of knots is a
specialization of some knot colouring polynomial. This provides a complete
topological interpretation of these invariants in terms of the knot group and
its peripheral system. Furthermore, we show that P can be presented as a
Yang-Baxter invariant, i.e. as the trace of some linear braid group
representation. This entails in particular that Yang-Baxter invariants can
detect non-inversible and non-reversible knots.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 11:05:51 GMT"
}
] | 2007-11-20T00:00:00 | [
[
"Eisermann",
"Michael",
""
]
] |
0707.3896 | Dorothy Buck | Dorothy Buck and Erica Flapan | A Topological Characterization Of Knots and Links Arising From
Site-Specific Recombination | 18 pages, 3 tables, 18 figures. See also arXiv:0707.3775v1 for
biological evidence for and applications of the model developed here | null | 10.1088/1751-8113/40/41/008 | null | math.GT | null | We develop a topological model of knots and links arising from a single (or
multiple processive) round(s) of recombination starting with an unknot, unlink,
or (2,m)-torus knot or link substrate. We show that all knotted or linked
products fall into a single family, and prove that the size of this family
grows linearly with the cube of the minimum number of crossings. Additionally,
we prove that the only possible products of an unknot substrate are either
clasp knots and links or (2,m)-torus knots and links. Finally, in the (common)
case of (2,m)-torus knot or link substrates whose products have minimal
crossing number m+1, we prove that the types of products are tightly
prescribed, and use this to examine previously uncharacterized experimental
data.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 10:59:03 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Buck",
"Dorothy",
""
],
[
"Flapan",
"Erica",
""
]
] |
0707.3897 | F. S. Bergeret | F. S. Bergeret, A. Levy Yeyati, A. Martin-Rodero | Josephson effect through a quantum dot array | 9 pages, 8 figures | Phys. Rev. B 76, 174510 (2007) | 10.1103/PhysRevB.76.174510 | null | cond-mat.supr-con cond-mat.str-el | null | We analyze the ground state properties of an array of quantum dots connected
in series between superconducting electrodes. This system is represented by a
finite Hubbard chain coupled at both ends to BCS superconductors. The ground
state is obtained using the Lanczos algorithm within a low energy theory in
which the bulk superconductors are replaced by effective local pairing
potentials. We study the conditions for the inversion of the sign of the
Josephson coupling ($\pi$-junction behavior) as a function of the model
parameters. Results are presented in the form of phase diagrams which provide a
direct overall view of the general trends as the size of the system is
increased, exhibiting a strong even-odd effect. The analysis of the spin-spin
correlation functions and local charges give further insight into the nature of
the ground state and how it is transformed by the presence of superconductivity
in the leads. Finally we study the scaling of the Josephson current with the
system size and relate these results with previous calculations of Josephson
transport through a Luttinger liquid.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 10:49:03 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Bergeret",
"F. S.",
""
],
[
"Yeyati",
"A. Levy",
""
],
[
"Martin-Rodero",
"A.",
""
]
] |
0707.3898 | Andrew R. Wade | Mathew D. Penrose and Andrew R. Wade | Multivariate normal approximation in geometric probability | 23 pages | Journal of Statistical Theory and Practice, Vol. 2 (2008), no. 2,
p. 293-326 | 10.1080/15598608.2008.10411876 | null | math.PR | null | Consider a measure $\mu_\lambda = \sum_x \xi_x \delta_x$ where the sum is
over points $x$ of a Poisson point process of intensity $\lambda$ on a bounded
region in $d$-space, and $\xi_x$ is a functional determined by the Poisson
points near to $x$, i.e. satisfying an exponential stabilization condition,
along with a moments condition (examples include statistics for proximity
graphs, germ-grain models and random sequential deposition models). A known
general result says the $\mu_\lambda$-measures (suitably scaled and centred) of
disjoint sets in $R^d$ are asymptotically independent normals as $\lambda \to
\infty$; here we give an $O(\lambda^{-1/(2d + \epsilon)})$ bound on the rate of
convergence. We illustrate our result with an explicit multivariate central
limit theorem for the nearest-neighbour graph on Poisson points on a finite
collection of disjoint intervals.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 11:10:48 GMT"
}
] | 2013-02-05T00:00:00 | [
[
"Penrose",
"Mathew D.",
""
],
[
"Wade",
"Andrew R.",
""
]
] |
0707.3899 | Daniel Arteaga | Daniel Arteaga | Particle propagation in non-trivial backgrounds: a quantum field theory
approach | 269 pages, 17 figures. PhD thesis, Universitat de Barcelona. One
reference added, minor typos corrected | null | null | null | hep-ph gr-qc hep-th | null | The basic aim of the thesis is the study of the propagation of particles and
quasiparticles in non-trivial backgrounds from the quantum field theory point
of view. By "non-trivial background" we mean either a non-vacuum state in
Minkowski spacetime or an arbitrary state in a curved spacetime. Starting with
the case of a flat spacetime, the basic properties of the particle and
quasiparticle propagation are analyzed using two different methods other than
the conventional mean-field-based techniques: on the one hand, the quantum
state corresponding to the quasiparticle excitation is explicitly constructed;
on the other hand, the spectral representation of the two-point propagators is
analyzed. Both methods lead to the same results: the energy and decay rate of
the quasiparticles are determined by the real and imaginary parts of the
retarded self-energy respectively. These general results are applied to two
particular quantum systems: first, a scalar particle immersed in a thermal
graviton bath; second, a simplified atomic model, seizing the opportunity to
connect with other statistical and first-quantized approaches. In the second
part of the thesis the results are extended to curved spacetime. Working with a
quasilocal quasiparticle concept the flat-spacetime results are recovered. In
cosmology, within the adiabatic approximation, it is possible to go beyond the
flat spacetime results and find additional effects due to the universe
expansion. The cosmologically-induced effects are analyzed, obtaining that
there might be an additional contribution to the particle decay due to the
universe expansion. In the de Sitter case, this additional contribution
coincides with the decay rate in a thermal bath in a flat spacetime at the
corresponding de Sitter temperature.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 11:07:00 GMT"
},
{
"version": "v2",
"created": "Thu, 13 Sep 2007 14:07:07 GMT"
}
] | 2016-09-08T00:00:00 | [
[
"Arteaga",
"Daniel",
""
]
] |
0707.3900 | Evgeny Korotyaev | Andrey Badanin, Jochen Br\"uning, Evgeny Korotyaev | Schr\"odinger operators on armchair nanotubes. II | 17 pages | null | null | null | math.SP math-ph math.MP | null | We consider the Schr\"odinger operator with a periodic potential on quasi-1D
models of armchair single-wall nanotubes. The spectrum of this operator
consists of an absolutely continuous part (intervals separated by gaps) plus an
infinite number of eigenvalues with infinite multiplicity. We describe the
absolutely continuous spectrum of the Schr\"odinger operator: 1) the
multiplicity, 2) endpoints of the gaps, they are given by periodic or
antiperiodic eigenvalues or resonances (branch points of the Lyapunov
function), 3) resonance gaps, where the Lyapunov function is non-real. We
determine the asymptotics of the gaps at high energy.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 11:21:34 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Badanin",
"Andrey",
""
],
[
"Brüning",
"Jochen",
""
],
[
"Korotyaev",
"Evgeny",
""
]
] |
0707.3901 | Bertrand Giraud | B. G. Giraud | Laboratory Density Functionals | 3 pages | null | null | null | nucl-th | null | We compare several definitions of the density of a self-bound system, such as
a nucleus, in relation with its center-of-mass zero-point motion. A trivial
deconvolution relates the internal density to the density defined in the
laboratory frame. This result is useful for the practical definition of density
functionals.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 14:37:15 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Giraud",
"B. G.",
""
]
] |
0707.3902 | Massimo Di Toro | M. Colonna, J. Rizzo, Ph. Chomaz, M. Di Toro | Probing the nuclear EOS with fragment production | 10 pages, 4 figures; Int.Nucl.Phys.Conf., Tokyo June 07, to appear in
Nucl.Phys.A (Elsart) | Nucl.Phys.A805:454-461,2008 | 10.1016/j.nuclphysa.2008.02.266 | null | nucl-th | null | We discuss fragmentation mechanisms and isospin transport occurring in
central collisions between neutron rich systems at Fermi energies. In
particular, isospin effects are analyzed looking at the correlations between
fragment isotopic content and kinematical properties. Simulations are based on
an approximate solution of the Boltzmann-Langevin (BL) equation. An attempt to
solve the complete BL equation, by introducing full fluctuations in phase space
is also discussed.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 11:37:17 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Colonna",
"M.",
""
],
[
"Rizzo",
"J.",
""
],
[
"Chomaz",
"Ph.",
""
],
[
"Di Toro",
"M.",
""
]
] |
0707.3903 | Silvio Capobianco | Silvio Capobianco | Multidimensional cellular automata and generalization of Fekete's lemma | 6 pages, no figures, LaTeX. Improved some explanations; revised
structure; added examples; renamed "hypercubes" into "right polytopes"; added
references to Arratia's paper on EJC, Calude's book, Cook's proof of Rule 110
universality, and arXiv paper 0709.1173 | null | null | null | math.GM math.DS | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Fekete's lemma is a well known combinatorial result on number sequences: we
extend it to functions defined on $d$-tuples of integers. As an application of
the new variant, we show that nonsurjective $d$-dimensional cellular automata
are characterized by loss of arbitrarily much information on finite supports,
at a growth rate greater than that of the support's boundary determined by the
automaton's neighbourhood index.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 11:40:55 GMT"
},
{
"version": "v2",
"created": "Tue, 14 Aug 2007 13:13:11 GMT"
},
{
"version": "v3",
"created": "Tue, 17 Jun 2008 13:51:32 GMT"
}
] | 2008-06-17T00:00:00 | [
[
"Capobianco",
"Silvio",
""
]
] |
0707.3904 | Jasper Kirkby | A. Barczyk, J. Kirkby, L. Malgeri (CERN), J. Berdugo, J. Casaus, C.
Mana, J. Marin, G. Martinez, E. Sanchez, C. Willmott (CIEMAT), C. Casella, M.
Pohl (University of Geneva), K. Deiters, P. Dick, C. Petitjean (PSI) (for the
FAST Collaboration) | Measurement of the Fermi Constant by FAST | 15 pages, 6 figures | Phys.Lett.B663:172-180,2008 | 10.1016/j.physletb.2008.04.006 | null | hep-ex | null | An initial measurement of the lifetime of the positive muon to a precision of
16 parts per million (ppm) has been performed with the FAST detector at the
Paul Scherrer Institute. The result is tau_mu = 2.197083 (32) (15) microsec,
where the first error is statistical and the second is systematic. The muon
lifetime determines the Fermi constant, G_F = 1.166353 (9) x 10^-5 GeV^-2 (8
ppm).
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 11:49:33 GMT"
},
{
"version": "v2",
"created": "Tue, 31 Jul 2007 12:51:41 GMT"
}
] | 2019-08-13T00:00:00 | [
[
"Barczyk",
"A.",
"",
"CERN"
],
[
"Kirkby",
"J.",
"",
"CERN"
],
[
"Malgeri",
"L.",
"",
"CERN"
],
[
"Berdugo",
"J.",
"",
"CIEMAT"
],
[
"Casaus",
"J.",
"",
"CIEMAT"
],
[
"Mana",
"C.",
"",
"CIEMAT"
],
[
"Marin",
"J.",
"",
"CIEMAT"
],
[
"Martinez",
"G.",
"",
"CIEMAT"
],
[
"Sanchez",
"E.",
"",
"CIEMAT"
],
[
"Willmott",
"C.",
"",
"CIEMAT"
],
[
"Casella",
"C.",
"",
"University of Geneva"
],
[
"Pohl",
"M.",
"",
"University of Geneva"
],
[
"Deiters",
"K.",
"",
"PSI"
],
[
"Dick",
"P.",
"",
"PSI"
],
[
"Petitjean",
"C.",
"",
"PSI"
]
] |
0707.3905 | Daphne Stam | D. M. Stam | Spectropolarimetric signatures of Earth-like extrasolar planets | 31 pages text, 17 figures, 1 table Submitted to A&A | null | 10.1051/0004-6361:20078358 | null | astro-ph | null | We present results of numerical simulations of the flux (irradiance), F, and
the degree of polarization (i.e. the ratio of polarized to total flux), P, of
light that is reflected by Earth-like extrasolar planets orbiting solar-type
stars, as functions of the wavelength (from 0.3 to 1.0 micron, with 0.001
micron spectral resolution) and as functions of the planetary phase angle. We
use different surface coverages for our model planets, including vegetation and
a Fresnel reflecting ocean, and clear and cloudy atmospheres. Our
adding-doubling radiative transfer algorithm, which fully includes multiple
scattering and polarization, handles horizontally homogeneous planets only; we
simulate fluxes and polarization of horizontally inhomogeneous planets by
weighting results for homogeneous planets. Like the flux, F, the degree of
polarization, P, of the reflected starlight is shown to depend strongly on the
phase angle, on the composition and structure of the planetary atmosphere, on
the reflective properties of the underlying surface, and on the wavelength, in
particular in wavelength regions with gaseous absorption bands. The sensitivity
of P to a planet's physical properties appears to be different than that of F.
Combining flux with polarization observations thus makes for a strong tool for
characterizing extrasolar planets. The calculated total and polarized fluxes
will be made available through the CDS.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 12:07:44 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Stam",
"D. M.",
""
]
] |
0707.3906 | Zhoujian Cao Dr | Zhoujian Cao, Pengfei Li, Hong Zhang and Gang Hu | Negative phase velocity in nonlinear oscillatory systems --mechanism and
parameter distributions | null | null | 10.1142/S0217979207045360 | null | cond-mat.mtrl-sci | null | Waves propagating inwardly to the wave source are called antiwaves which have
negative phase velocity. In this paper the phenomenon of negative phase
velocity in oscillatory systems is studied on the basis of periodically paced
complex Ginzbug-Laundau equation (CGLE). We figure out a clear physical picture
on the negative phase velocity of these pacing induced waves. This picture
tells us that the competition between the frequency $\omega_{out}$ of the
pacing induced waves with the natural frequency $\omega_{0}$ of the oscillatory
medium is the key point responsible for the emergence of negative phase
velocity and the corresponding antiwaves. $\omega_{out}\omega_{0}>0$ and
$|\omega_{out}|<|\omega_{0}|$ are the criterions for the waves with negative
phase velocity. This criterion is general for one and high dimensional CGLE and
for general oscillatory models. Our understanding of antiwaves predicts that no
antispirals and waves with negative phase velocity can be observed in excitable
media.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 12:11:14 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Cao",
"Zhoujian",
""
],
[
"Li",
"Pengfei",
""
],
[
"Zhang",
"Hong",
""
],
[
"Hu",
"Gang",
""
]
] |
0707.3907 | Benno List | Michael Klasen, Benno List, Stephanie Hansmann-Menzemer and Rainer
Mankel | Summary of the Heavy Flavor Working Group | 17 pages, 3 figures, to appear in the Proceedings of the XV
International Workshop on Deep-Inelastic Scattering and Related Subjectes,
DIS 2007, April 16--20, 2007, Munich, Germany | null | null | LPSC 07-73 | hep-ph | null | During the last year many important results have been achieved in heavy
flavour physics: New measurements of charm and beauty production have been
performed at HERA and the Tevatron. A wealth of new spectroscopy data with
several new, unexpected states in the charmonium and the D_s systems has been
collected and b to d gamma transitions have been established. The oscillation
frequency in the B_s Bbar_s is now measured, and mixing in the D0 D0bar system
has been observed. Theoretical progress in the areas of open heavy flavour
production, quarkonium production and decays, and multiquark spectroscopy has
been presented at this workshop.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 12:12:25 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Klasen",
"Michael",
""
],
[
"List",
"Benno",
""
],
[
"Hansmann-Menzemer",
"Stephanie",
""
],
[
"Mankel",
"Rainer",
""
]
] |
0707.3908 | Roberto Raimondi | Cosimo Gorini, Peter Schwab, Michael Dzierzawa, Roberto Raimondi | Quasiclassical approach and spin-orbit coupling | 3 pages, Submitted to Physica E | null | 10.1016/j.physe.2007.08.006 | null | cond-mat.mes-hall | null | We discuss the quasiclassical Green function method for a two-dimensional
electron gas in the presence of spin-orbit coupling, with emphasis on the
meaning of the $\xi$-integration procedure. As an application of our approach,
we demonstrate how the spin-Hall conductivity, in the presence of spin-flip
scattering, can be easily obtained from the spin-density continuity equation.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 12:12:36 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Gorini",
"Cosimo",
""
],
[
"Schwab",
"Peter",
""
],
[
"Dzierzawa",
"Michael",
""
],
[
"Raimondi",
"Roberto",
""
]
] |
0707.3909 | Evgeny Korotyaev | Andrey Badanin, Jochen Br\"uning, Evgeny Korotyaev, Igor Lobanov | Schr\"odinger operators on armchair nanotubes. I | 17 pages | null | null | null | math-ph math.MP math.SP | null | We consider the Schr\"odinger operator with a periodic potential on quasi-1D
models of armchair single-wall nanotubes. The spectrum of this operator
consists of an absolutely continuous part (intervals separated by gaps) plus an
infinite number of eigenvalues with infinite multiplicity. We describe all
eigenfunctions with the same eigenvalue. We define a Lyapunov function, which
is analytic on some Riemann surface. On each sheet, the Lyapunov function has
the same properties as in the scalar case, but it has branch points, which we
call resonances. In example we show the existence of real and complex
resonances for some specific potentials.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 12:16:50 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Badanin",
"Andrey",
""
],
[
"Brüning",
"Jochen",
""
],
[
"Korotyaev",
"Evgeny",
""
],
[
"Lobanov",
"Igor",
""
]
] |
0707.3910 | Victor H. Moll | George Boros and Victor H. Moll | Landen transformations and the integration of rational functions | 20 pages | Math. Comp. 71, 2002, 649-668 | null | null | math.CA | null | We present a rational version of the classical Landen transformation for
elliptic integrals. This is employed to obtain explicit closed-form expressions
for a large class of integrals of even rational functions and to develop an
algorithm for the numerical integration of these functions.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 12:27:33 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Boros",
"George",
""
],
[
"Moll",
"Victor H.",
""
]
] |
0707.3911 | Victor H. Moll | Dante Manna and Victor H. Moll | A simple example of a new class of Landen transformation | 12 pages | Amer. Math. Monthly 114, 2007, 232-241 | null | null | math.CA | null | The rational Landen transformation is a map on the coefficients of a rational
integrand that preserves the value of the integral. This is the rational analog
of the classical Landen transformations for elliptic integrals that leads to
the arithmetic-geometric mean of Legendre and Gauss. We present the effect of
this transformation in the simplest possible case.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 12:39:19 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Manna",
"Dante",
""
],
[
"Moll",
"Victor H.",
""
]
] |
0707.3912 | Thi Nguyet Trinh | Thi Nguyet Trinh (for the H1 Collaboration) | Search for Excited Leptons at HERA | 4 pages, 3 figures; To appear in the proceedings of 15th
International Workshop on Deep Inelastic Scattering and Related Subjects (DIS
2007), Munich, Germany, 16-20 Apr 2007 | null | null | null | hep-ex | null | Searches for excited electrons and neutrinos have been performed using the
complete HERA I and II data samples collected by the H1 detector at
$\sqrt{s}=320$ GeV corresponding to an integrated luminosity of up to 435
pb$^{-1}$. In absence of a signal, the limits on the ratio of the coupling to
the compositeness scale derived extend the excluded region to higher masses
than has been possible in previous searches.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 13:13:21 GMT"
}
] | 2019-08-14T00:00:00 | [
[
"Trinh",
"Thi Nguyet",
"",
"for the H1 Collaboration"
]
] |
0707.3913 | Marco Lucamarini | M. Lucamarini, J. S. Shaari, M. R. B. Wahiddin | Deterministic Rendering of BB84 for Practical Quantum Cryptography | 9 pages, 2 figures | null | null | null | quant-ph | null | We describe how to modify the BB84 protocol for quantum cryptography in order
to make it deterministic. We study both theoretical and experimental aspects of
this issue, showing that the new scheme is as secure as the old one, more
efficient on small-scale distances, and within the range of current technology.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 12:56:04 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Lucamarini",
"M.",
""
],
[
"Shaari",
"J. S.",
""
],
[
"Wahiddin",
"M. R. B.",
""
]
] |
0707.3914 | Marat Rovinsky | U. Jannsen, M. Rovinsky | Smooth representations and sheaves | 20 pages, final version | null | null | null | math.AG | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | The paper is concerned with `geometrization' of smooth (i.e. with open
stabilizers) representations of the automorphism group of universal domains,
and with the properties of `geometric' representations of such groups. As an
application, we calculate the cohomology groups of several classes of smooth
representations of the automorphism group of an algebraically closed extension
of infinite transcendence degree of an algebraically closed field.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 13:08:19 GMT"
},
{
"version": "v2",
"created": "Thu, 27 Nov 2008 14:27:36 GMT"
},
{
"version": "v3",
"created": "Tue, 7 Apr 2009 16:25:01 GMT"
}
] | 2009-04-07T00:00:00 | [
[
"Jannsen",
"U.",
""
],
[
"Rovinsky",
"M.",
""
]
] |
0707.3915 | Stephane Toulin | Yves Garrabos (ICMCB), Carole Lecoutre-Chabot (ICMCB), Fabien Palencia
(ICMCB), Bernard Le Neindre (LIMHP), Can John Erkey | Master crossover functions for the one-component fluid "subclass" | null | Physical Review E: Statistical, Nonlinear, and Soft Matter Physics
77, 2 (2008) 021116 (26 p.) | 10.1103/PhysRevE.77.021116 | null | cond-mat.stat-mech | null | Introducing three well-defined dimensionless numbers, we establish the link
between the scale dilatation method able to estimate master (i.e. unique)
singular behaviors of the one-component fluid "subclass" and the universal
crossover functions recently estimated [Garrabos and Bervillier, Phys. Rev. E
74, 021113 (2006)] from the bounded results of the massive renormalization
scheme applied to the...
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 13:10:54 GMT"
}
] | 2008-02-18T00:00:00 | [
[
"Garrabos",
"Yves",
"",
"ICMCB"
],
[
"Lecoutre-Chabot",
"Carole",
"",
"ICMCB"
],
[
"Palencia",
"Fabien",
"",
"ICMCB"
],
[
"Neindre",
"Bernard Le",
"",
"LIMHP"
],
[
"Erkey",
"Can John",
""
]
] |
0707.3916 | Leandro Aolita | L. Aolita, K. Kim, J. Benhelm, C. F. Roos, and H. H\"affner | High-fidelity ion-trap quantum computing with hyperfine clock states | 4 pages, 1 figure | Phys. Rev. A 76, 040303(R) 2007 | 10.1103/PhysRevA.76.040303 | null | quant-ph | null | We propose the implementation of a geometric-phase gate on
magnetic-field-insensitive qubits with $\hat{\sigma}^z$-dependent forces for
trapped ion quantum computing. The force is exerted by two laser beams in a
Raman configuration. Qubit-state dependency is achieved by a small frequency
detuning from the virtually-excited state. Ion species with excited states of
long radiative lifetimes are used to reduce the chance of a spontaneous photon
emission to less than 10$^{-8}$ per gate-run. This eliminates the main source
of gate infidelity of previous implementations. With this scheme it seems
possible to reach the fault tolerant threshold.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 13:24:18 GMT"
},
{
"version": "v2",
"created": "Mon, 13 Aug 2007 01:14:02 GMT"
},
{
"version": "v3",
"created": "Mon, 27 Aug 2007 14:56:51 GMT"
},
{
"version": "v4",
"created": "Fri, 19 Oct 2007 15:02:10 GMT"
},
{
"version": "v5",
"created": "Wed, 24 Oct 2007 03:14:10 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Aolita",
"L.",
""
],
[
"Kim",
"K.",
""
],
[
"Benhelm",
"J.",
""
],
[
"Roos",
"C. F.",
""
],
[
"Häffner",
"H.",
""
]
] |
0707.3917 | David Menzies | David Menzies and Natalia Korolkova | Weak Values and Continuous-Variable Entanglement Concentration | 4 pages, 1 figure, Final version to appear in Phys. Rev. A | null | 10.1103/PhysRevA.76.062310 | null | quant-ph | null | We demonstrate a general weak measurement model which allows Gaussian
preserving entanglement concentration of the two mode squeezed vacuum. The
power of this simple and elegant protocol is through the constraints it places
on possible ancilla states and measurement strategies that will allow
entanglement concentration. In particular, it is shown how previously
discovered protocols of this kind emerge as special examples of the general
model described here. Finally, as evidence of its utility, we use it to provide
another novel example of such a protocol.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 13:32:22 GMT"
},
{
"version": "v2",
"created": "Thu, 1 Nov 2007 13:46:36 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Menzies",
"David",
""
],
[
"Korolkova",
"Natalia",
""
]
] |
0707.3918 | Stefano Bellucci | S. Bellucci, F. Carillo and P. Onorato | Spin separation in a T ballistic nanojunction due to
lateral-confinement-induced spin-orbit-coupling | 6 pages, 5 figures, PACS numbers: 72.25.-b, 72.20.My, 73.50.Jt,
accepted for publication in J. Phys. - Cond. Mat | null | 10.1088/0953-8984/19/39/395018 | null | cond-mat.mes-hall | null | We propose a new scheme of spin filtering employing ballistic nanostructures
in two dimensional electron gases (2DEGs). The proposal is essentially based on
the spin-orbit (SO) interaction arising from the lateral confining electric
field. This sets the basic difference with other works employing ballistic
crosses and T junctions with the conventional SO term arising from 2DEG
confinement. We discuss the consequences of this different approach on
magnetotransport properties of the device, showing that the filter can in
principle be used not only to generate a spin polarized current but also to
perform an electric measurement of the spin polarization of a charge current.
We focus on single-channel transport and investigate numerically the spin
polarization of the current.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 13:35:36 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Bellucci",
"S.",
""
],
[
"Carillo",
"F.",
""
],
[
"Onorato",
"P.",
""
]
] |
0707.3919 | Tomas Janssen | Tomas Janssen and Tomislav Prokopec | A graviton propagator for inflation | 23 pages | Class.Quant.Grav.25:055007,2008 | 10.1088/0264-9381/25/5/055007 | ITP-UU-07/37, SPIN-07/25 | gr-qc | null | We construct the scalar and graviton propagator in quasi de Sitter space up
to first order in the slow roll parameter $\epsilon\equiv -\dot{H}/H^2$. After
a rescaling, the propagators are similar to those in de Sitter space with an
$\epsilon$ correction to the effective mass. The limit $\epsilon\to 0$
corresponds to the E(3) vacuum that breaks de Sitter symmetry, but does not
break spatial isotropy and homogeneity. The new propagators allow for a
self-consistent, dynamical study of quantum back-reaction effects during
inflation.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 14:52:36 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Janssen",
"Tomas",
""
],
[
"Prokopec",
"Tomislav",
""
]
] |
0707.3920 | Chris Van Den Broeck | K. G. Arun, Bala R. Iyer, B.S. Sathyaprakash, Siddhartha Sinha, Chris
Van Den Broeck | Higher signal harmonics, LISA's angular resolution, and dark energy | 15 pages, no figures. Final version to appear in Phys. Rev. D | Phys.Rev.D76:104016,2007; Erratum-ibid.D76:129903,2007 | 10.1103/PhysRevD.76.104016 10.1103/PhysRevD.76.129903 | null | astro-ph gr-qc | null | It is generally believed that the angular resolution of the Laser
Interferometer Space Antenna (LISA) for binary supermassive black holes (SMBH)
will not be good enough to identify the host galaxy or galaxy cluster. This
conclusion, based on using only the dominant harmonic of the binary SMBH
signal, changes substantially when higher signal harmonics are included in
assessing the parameter estimation problem. We show that in a subset of the
source parameter space the angular resolution increases by more than a factor
of 10, thereby making it possible for LISA to identify the host galaxy/galaxy
cluster. Thus, LISA's observation of certain binary SMBH coalescence events
could constrain the dark energy equation of state to within a few percent,
comparable to the level expected from other dark energy missions.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 14:47:42 GMT"
},
{
"version": "v2",
"created": "Wed, 24 Oct 2007 14:22:06 GMT"
}
] | 2014-11-18T00:00:00 | [
[
"Arun",
"K. G.",
""
],
[
"Iyer",
"Bala R.",
""
],
[
"Sathyaprakash",
"B. S.",
""
],
[
"Sinha",
"Siddhartha",
""
],
[
"Broeck",
"Chris Van Den",
""
]
] |
0707.3921 | Ikuko Hamamoto | I. Hamamoto and S. Shimoura | Properties of 12Be and 11Be in terms of single-particle motion in
deformed potential | 17 pages, 1 figure | J.Phys.G34:2715-2726,2007 | 10.1088/0954-3899/34/12/015 | null | nucl-th | null | Inspired by the recent measurement of the B(E2;$0_{2}^{+} \to 2_{1}^+$) and
B(E0;$0_{2}^{+} \to 0_{1}^+$) values in $^{12}$Be, we give an interpretation of
available spectroscopic data on both $^{12}$Be and $^{11}$Be, using a simple
model which contains the essential feature of these two nuclei; the presence of
weakly-bound neutron(s) in deformed potentials. The agreement of the calculated
results with observed data is surprisingly good, including well-known strong E1
transitions in both nuclei.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 13:46:36 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Hamamoto",
"I.",
""
],
[
"Shimoura",
"S.",
""
]
] |
0707.3922 | Loriano Bonora | L. Bonora, R. P. Malik | BRST, anti-BRST and gerbes | 11 pages, typo corrected in eq.(3,8,24) | Phys.Lett.B655:75-79,2007 | 10.1016/j.physletb.2007.08.063 | SISSA/49/2007/EP | hep-th | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | We discuss BRST and anti--BRST transformations for an Abelian antisymmetric
gauge field in 4D and find that, in order for them to anticommute, we have to
impose a condition on the auxiliary fields. This condition is similar to the
Curci-Ferrari condition for the 4D non--Abelian 1-form gauge theories and
represents a consistency requirement. We interpret it as a signal that our
Abelian 2-form gauge field theory is based on gerbes. To support this
interpretation we discuss, in particular, the case of the 1-gerbe for our
present field theory and write the relevant equations and symmetry
transformations for 2-gerbes.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 13:55:33 GMT"
},
{
"version": "v2",
"created": "Wed, 29 Aug 2007 12:18:07 GMT"
},
{
"version": "v3",
"created": "Tue, 1 Apr 2008 17:38:36 GMT"
},
{
"version": "v4",
"created": "Mon, 23 Feb 2009 18:06:14 GMT"
}
] | 2009-02-23T00:00:00 | [
[
"Bonora",
"L.",
""
],
[
"Malik",
"R. P.",
""
]
] |
0707.3923 | Stefano Bellucci | S. Bellucci and P. Onorato | Filtering of spin currents based on ballistic ring | 9 pages, 7 figures, PACS numbers: 72.25.-b, 72.20.My, 73.50.Jt,
accepted for publication in J. Phys. - Cond. Mat | null | 10.1088/0953-8984/19/39/395020 | null | cond-mat.mes-hall | null | Quantum interference effects in rings provide suitable means for controlling
spin at mesoscopic scales. Here we apply such a control mechanism to the
spin-dependent transport in a ballistic quasi one dimensional ring patterned in
two dimensional electron gases (2DEGs). The study is essentially based on the
{\it natural} spin-orbit (SO) interactions, one arising from the laterally
confining electric field {($\beta$ term) and the other due to to the
quantum-well potential that confines electrons in the 2DEG (conventional Rashba
SO interaction or $\alpha$ term).} We focus on single-channel transport and
solve analytically the spin polarization of the current. As an important
consequence of the presence of spin splitting, we find the occurrence of spin
dependent current oscillations.
We analyze %the effects of disorder by discussing the transport in the
presence of one non-magnetic obstacle in the ring. We demonstrate that a spin
polarized current can be induced when an unpolarized charge current is injected
in the ring, by focusing on the central role that the presence of the obstacle
plays.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 14:05:35 GMT"
}
] | 2009-11-13T00:00:00 | [
[
"Bellucci",
"S.",
""
],
[
"Onorato",
"P.",
""
]
] |
0707.3924 | Petr Seba | Petr Seba | Parking in the city | null | null | null | null | nlin.AO nlin.CG | null | We show that the spacing distribution between parked cars can be obtained as
a solution of certain linear distributional fixed point equation. The results
are compared with the data measured on the streets of Hradec Kralove. We also
discuss a relation of this results to the random matrix theory.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 14:06:32 GMT"
},
{
"version": "v2",
"created": "Thu, 15 Nov 2007 16:58:13 GMT"
},
{
"version": "v3",
"created": "Thu, 22 Nov 2007 12:58:02 GMT"
}
] | 2007-11-22T00:00:00 | [
[
"Seba",
"Petr",
""
]
] |
0707.3925 | Andries Hekstra | Andries P. Hekstra | Use of a $d$-Constraint During LDPC Decoding in a Bliss Scheme | null | null | null | null | cs.IT math.IT | null | Bliss schemes of a run length limited (RLL) codec in combination with an LDPC
codec, generate LDPC parity bits over a systematic sequence of RLL channel bits
that are inherently redundant as they satisfy e.g. a $d=1$ minimum run length
constraint. That is the subsequences consisting of runs of length $d=1$, viz.
$...010...$ and $...101...$, cannot occur. We propose to use this redundancy
during LDPC decoding in a Bliss scheme by introducing additional $d$-constraint
nodes in the factor graph used by the LDPC decoder. The messages sent from
these new nodes to the variable or codeword bit nodes exert a ``force'' on the
resulting soft-bit vector coming out of the LDPC decoding that give it a
tendency to comply with the $d$-constraints. This way, we can significantly
reduce the probability of decoding error.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 14:08:07 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Hekstra",
"Andries P.",
""
]
] |
0707.3926 | Jennifer Schultens | Jennifer Schultens | Covering spaces and the Kakimizu complex | 16 pages, 10 figures | Journal of Topology 3 (2010) 883--900 | null | null | math.GT | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | In 1992, Osamu Kakimizu defined a complex that has become known as the
Kakimizu complex of a knot. Vertices correspond to isotopy classes of minimal
genus Seifert surfaces of the knot. Higher dimensional simplices correspond to
collections of such classes of Seifert surfaces that admit disjoint
representatives. We show that this complex is simply connected.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 14:10:50 GMT"
},
{
"version": "v2",
"created": "Mon, 30 Jul 2007 13:55:24 GMT"
},
{
"version": "v3",
"created": "Mon, 27 Aug 2007 19:12:25 GMT"
},
{
"version": "v4",
"created": "Wed, 15 Jan 2014 10:34:41 GMT"
}
] | 2014-01-16T00:00:00 | [
[
"Schultens",
"Jennifer",
""
]
] |
0707.3927 | Tarun Kanti Ghosh | Tarun Kanti Ghosh | Dynamic structure factor of Fermi superfluid in the BEC-BCS crossover | To appear in Physical Review A | Physical Review A 76, 033602 (2007) | 10.1103/PhysRevA.76.033602 | null | cond-mat.other | null | We consider cigar shaped Fermi superfluid in the BEC-BCS crossover. Using
polytropic form of equation of state, we derive low energy multibranch bosonic
excitations and the corresponding density fluctuations in three different
regimes along the crossover, namely weak-coupling BCS, unitarity and molecular
BEC regimes. Bragg spectroscopy can be used to probe the multibranch nature of
the low energy bosonic excitations by measuring dynamic structure factor.
Therefore, we calculate dynamic structure factor in those three different
regimes. In the Bragg spectroscopy, an actual observable is momentum imparted
to the superfluid due to the Bragg potential. We also present results of the
momentum imparted to the superfluid due to the Bragg pulses.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 14:12:26 GMT"
}
] | 2007-09-08T00:00:00 | [
[
"Ghosh",
"Tarun Kanti",
""
]
] |
0707.3928 | Jay Rosen | Michael Marcus and Jay Rosen | Asymptotic expansions for functions of the increments of certain
Gaussian processes | null | null | null | null | math.PR | http://arxiv.org/licenses/nonexclusive-distrib/1.0/ | Let $G=\{G(x),x\ge 0\}$ be a mean zero Gaussian process with stationary
increments and set $\sigma^2(|x-y|)= E(G(x)-G(y))^2$. Let $f$ be a function
with $Ef^{2}(\eta)<\ff$, where $\eta=N(0,1)$. When $\sigma^2$ is regularly
varying at zero and \[
\lim_{h\to 0}{h^2\over \sigma^2(h)}= 0\qquad {and}\qquad \lim_{h\to
0}{\sigma^2(h)\over h}= 0
\quad {but} \quad ({d^{2}\over ds^2}\sigma^2(s))^{j_0} \] is locally
integrable for some integer $j_0\ge 1$, and satisfies some additional
regularity conditions, \bea && \int_a^bf(\frac{G(x+h)-G(x)}{\sigma (h)}) dx
\label{abst}\nn &&\qquad = \sum_{j=0}^{j_0} (h/\sigma(h))^{j} {E(H_{j}(\eta)
f(\eta))\over\sqrt {j!}} :(G')^{j}:(I_{[a,b]}) +o({h\over\sigma (h)})^{j_0}\nn
\eea in $L^2$. Here $H_j$ is the $j$-th Hermite polynomial. Also
$:(G')^{j}:(I_{[a,b]})$ is a $j $-th order Wick power Gaussian chaos
constructed from the Gaussian field $ G'(g) $, with covariance \[ E(G'(g)G'(\wt
g)) = \int \int \rho (x-y)g(x)\wt g(y) dx dy\label{3.7bqs}, \] where $
\rho(s)={1/2}{d^{2}\over ds^2}\sigma^2(s)$.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 14:14:18 GMT"
},
{
"version": "v2",
"created": "Thu, 15 Oct 2009 15:44:07 GMT"
}
] | 2009-10-15T00:00:00 | [
[
"Marcus",
"Michael",
""
],
[
"Rosen",
"Jay",
""
]
] |
0707.3929 | Susumu Koretune | Susumu Koretune | The sum rules for the spin dependent structure functions corresponding
to the moment at $n=0$ | 12 pages, 2 figures, Contributed paper to Lepton-Photon 2007 | null | null | null | hep-ph | null | Sum rules for the spin dependent structure functions corresponding to the
moment at $n=0$ derived from the current algebra based on the canonical
quantization on the null-plane are reviewed.
| [
{
"version": "v1",
"created": "Thu, 26 Jul 2007 14:22:38 GMT"
}
] | 2007-07-27T00:00:00 | [
[
"Koretune",
"Susumu",
""
]
] |
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