Chaeropus, known as the pig-footed bandicoots, is a genus of small marsupials that became extinct during the 20th century. They were the only members of the family Chaeropodidae in order Peramelemorphia (bandicoots and bilbies), with unusually thin legs, yet were able to move rapidly. Two recognised species inhabited dense vegetation on the arid and semiarid plains of Australia. The genus' distribution range was later reduced to an inland desert region, where it was last recorded in the 1950s; it is now presumed extinct.

Taxonomy
The genus was proposed by William Ogilby in a presentation to the Linnean Society of London of a new species tentatively assigned to a genus of bandicoots, the long-nosed Perameles, and was forwarded to John Gould, then at Sydney, for a more detailed examination. Ogilby submitted a drawing by collector Major Mitchell, who also supplied extensive remarks on the animal's form and habits, and identified the unusual pig-like toes of the forelimbs as the basis for a new genus.
The collection of the specimen was made at the interior of New South Wales by Mitchell, on the banks of the Murray River.

The genus name Chaeropus combines terms from Ancient Greek for "pig" and "foot", a reference to the unique characteristic of the forelimbs noted by the describing author. The specific epithet ecaudatus refers to the absence of a tail, which the single specimen happened to be missing, leading to the unfortunate suggestion by the name that the marsupial did not possess them.

The recognised synonymy of the genus was published by Theodore S. Palmer in 1904.
A nomenclatural synonym, Chœropus [Choeropus] Waterhouse, G.R. 1841, was published several years after Ogilby as an unjustified emendation; Waterhouse gives the spelling proposed by Ogilby in the same work.
Oldfield Thomas noted the inappropriate epithet ecaudatus in 1888, substituting the name Chœropus castanotis proposed by John Edward Gray as the type of the genus, but this was suppressed as a synonym by Palmer.

The vernacular description, pig-footed bandicoot, was given by Ogilby in his first description, a name ascribed by Mitchell's party.
Europeans settlers reported the species as resembling "small antelopes", a simile that was reported by Bernard Woodward as persisting until their disappearance around 1900. The names recorded from the Noongar language are  and .
According to Indigenous Australian trackers, the pig-footed bandicoot was known as landwang and tubaija  in their culture.

Classification
This genus was previously placed in the family Peramelidae, along with the bilbies, as the subfamily Chaeropodinae by McKenna and Bell (1997). However, its form is quite distinct, and recent molecular evidence supports this distinction. It is believed to be the sister group of the rest of the Peramelemorphia, and has been assigned to its own family, the Chaeropodidae. The divergence of Chaeropus from other members of the Peramelemorphia is estimated to be in the Mid-Late Oligocene, around 26.7 Mya (21.9–31.3 confidence interval).

Until 2019, both species were grouped under C. ecaudatus as the pig-footed bandicoot; however, a 2019 study split the genus into two species - the northern pig-footed bandicoot (C. yirratji) and the southern pig-footed bandicoot (C. ecaudatus). In 2016, a fossil species C. baynesi was described from Late Pliocene to Early Pleistocene (2.47–2.92 Mya) of south-west New South Wales.

The arrangement within the Marsupialia, with the treatment proposed in the 2019 revision,  may be summarised as:

 Peramelemorphia
Thylacomyidae (Macrotis, the bilbies)
Chaeropodidae
Chaeropus
Chaeropus ecaudatus
Chaeropus ecaudatus ecaudatus
Chaeropus ecaudatus occidentalis
Chaeropus yirratji
Peramelidae (extant genera known as bandicoots)

Description

A genus of Peramelemorphia order of marsupials, allied by a monophyletic family, and regarded as exceptional in their morphology. The direct evidence of the two species is limited to 29 specimens remaining at museums in Australia and overseas.
Their superficial appearance resembled the native bandicoots or rat kangaroos, although very small and dainty, and comparable to the size of a young rabbit or kitten.

The feet of forelimbs resemble those of the genus Sus and the hind legs seen as similar to a horse.
The species had a body size of  and a  tail. In form, they were almost bilby-like on first sight, having long, slender limbs, large, pointed ears, and a long tail. On closer examination, however, it became apparent that the pig-footed bandicoots were very unusual for marsupials. The forefeet had two functional toes with hooves, similar to the cloven hoof of a pig or deer; this is possibly due to juveniles being deposited in the pouch through external stalks, thus relieving them of using the forelimbs while as joeys. The hind feet had an enlarged fourth toe with a heavy claw shaped like a tiny horse's hoof, with the other toes being vestigial; only the fused second and third toes were useful, and that not for locomotion, but grooming.

They had broad heads, and a long yet slender snout. Their fur was coarse and straight, but not spiny. In color, they varied from grizzled grey through fawn to orange-brown, and the belly and underparts were white with the fur on the ears being of chestnut color.

The genus had five pairs of upper and three pairs of lower incisor teeth; tooth shape differed between the two species. The females of the genus had eight nipples and the opening of the pouch was faced backwards, not forwards as is the case with kangaroos.

Depictions of the species include a lithograph by Henry C. Richter in John Gould's Mammals of Australia, published in the mid-19th century.
An unpublished illustration by Richter, under the direction of Gould, was discovered in the archives of Knowsley Hall, at one time home to a great patron of natural history, the Earl of Derby.
The species C. ecaudatus was selected by Peter Schouten and Tim Flannery for a series of paintings illustrating the known information on the species' appearance and habits, published in a book surveying the modern extinctions of animals.
Another reconstruction of the genus was produced by Schouten to illustrate the species C. yirratji.

Distribution and habitat
The two species were native to western New South Wales and Victoria, the southern part of the Northern Territory and South Australia and Western Australia. Chaeropus ecaudatus populated semiarid southern regions of southern Australia, extending to southwest Australia, while C. yirratji populated sandy environments extending from Western Australia to the deserts in central Australia. They inhabited a wide range of habitat types, from grassy woodland and grassland plains to the spinifex country and arid flats of central Australia. Despite its wide range, the genus had a sparse distribution and was never abundant.

The number of complete specimens found in museum collections is 29. Historical records of collections in central and western Australia, where it was sometimes locally common, begin with a specimen obtained at the Peron Peninsula during the Uranie expedition led by Louis de Freycinet in 1818. John Gilbert recorded his observations at dense stands of Casuarina seedlings (Allocasuarina species) at the interior of the southwest, beyond Northam, but did not appear in the Avon valley, inland from the new colony at Perth, at new settlements near Toodyay, York, and the Wongan Hills area. On his second collecting expedition in the southwest he recorded the species at King George Sound, on the southern coast of Western Australia.
The species was not recorded in the lists produced by the Austin Expedition of 1854, although W. A. Sanford was informed of a frequently seen animal, described as the "chestnut-eared hog's-foot", which Ludwig Glauert suggests was too common to merit notice in Austin's published report. Despite actively searching and collecting information on this animal, the species was not recorded by John Tunney, George Masters, or Guy Shortridge in their extensive surveys of western regions during the subsequent decades.
The last record of Chaeropus in the Southwest Australian region was in 1898, at Youndegin, consistent with the disappearance of species in a critical weight range that succumbed to Australia's mammalian faunal collapse (1875–1925).

Archaeological evidence of the genus shows a greater range during Holocene and the earlier Pleistocene epoch. Specimens were uncovered in the first examination of fossil deposits at Mammoth Cave (Western Australia), at the beginning of the twentieth century, and great extension of the known range to eastern Queensland at two sites examined a century later.
The appearance in the fossil fauna of eastern Queensland sites demonstrates the replacement of rainforest communities with the open grassy habitat favoured by this genus during the later Pleistocene.
A survey of mammal fauna in the northeast of South Australia uncovered a fragment in an owl pellet buried beneath sediments.

Explorer Samuel Albert White was shown the tracks of the animal in 1921 and gained information on its habitat, being found on stony tablelands or at sand dunes in central Australia, and was able to capture one with the assistance of a local Aboriginal woman and her dogs.
The increasing rarity of the animal had it included on a list of prohibited exports, either live or skin, issued by the federal government in 1921.

Extinction

According to Indigenous Australian oral tradition, pig-footed bandicoots were rare even before the arrival of Europeans on the continent, and were in a serious decline even as it first came to scientific notice in the middle years of the 19th century. Two specimens of pig-footed bandicoots were obtained by local people in 1857 for Gerard Krefft, who accompanied the Blandowski Expedition. In trying to communicate the species he sought, Krefft showed a drawing to his collectors that showed the absence of a tail; the first specimens he was supplied were bandicoots with the tails removed. Despite the trouble taken in gaining living specimens, Krefft recorded his observations with an apology for eating one of them. Only a handful of specimens was collected through the second part of the 19th century, mostly from northwestern Victoria, but also from arid country in South Australia, Western Australia, and the Northern Territory. By the start of the 20th century, they had become extinct in Victoria and the south-west of Western Australia. The last certain specimen was collected in 1901.  By 1945, C. ecaudatus was extinct, having vanished from South Australia, and C. yirratji was reported to be limited to "a slight foothold in central Australia". Nevertheless, Aboriginal people report that C. yirratji survived as late as the 1950s in the Gibson Desert and the Great Sandy Desert of Western Australia.

The cause of the extinction remains uncertain; neither of the two most destructive introduced exterminator species, the fox and the rabbit, had yet arrived in south-west Western Australia when the pig-footed bandicoots disappeared from that area. Feral cats were already common, which may offer an explanation; perhaps more likely, the decline was caused by a double habitat change. Firstly, the end of many thousands of years of Aboriginal burning, which being confined to a patchwork of small areas at any one time, had ensured both fresh new growth in the recently burnt areas and adjacent older growth for shelter and as a base for recolonisation. Australia's Aboriginal population had declined by around 90% during the 19th century, largely because of the introduction of European diseases, and the remaining Aborigines were often no longer permitted to carry on their traditional land-management and hunting practices. Secondly, following on the heels of the near-extermination of the Aborigines, came the introduction of vast numbers of sheep and cattle, leading to significant changes in soil structure, plant growth, and food availability.

The species was included in historical modelling of a disease outbreak, a theorised epizootic that was the primary cause of mammalian declines, to which the populations of Chaeropus would seem to have been highly susceptible. The sudden demise of these marsupials was noted by Hal Colebatch, writing in 1929 that the disappearance was not the result of direct actions of settlers, but an unexplained consequence of a natural event.
The apparent resilience of some mammals at Kellerberrin, which reappeared after a localised collapse, did not include this genus.
When modelled as a primary factor in their demise, which has no discernible secondary factors, the population had no immunity to the hypothetical epizootic.

An ethnographic survey of Aboriginal informants from central Australia in 1988 found the animal has not been seen in southern regions for around 70 years, but had persisted in the central desert regions until 30–50 years earlier.

Behaviour and ecology

Few naturalists had the opportunity to observe and document the behaviour of the two species, with one of the few existing accounts suggesting that it moved "like a broken-down hack in a canter, apparently dragging the hind quarters after it".
This is contradicted by the Aboriginal people of central Australia, who knew it well and reported that if disturbed, it was capable of running with considerable speed by breaking into a smooth, galloping sprint.

Chaeropus species moved with a distinctive gait, exaggerated by their proportionally long and slender limbs that resemble a large grazing mammal like the African antelope. Each forelimb had two functional toes and the rear limb ending in a hoof-like toe, with an apparent advantage when used to quickly evade a perceived threat.
They were solitary, nocturnal animals that would sleep in their shelter during the day and emerge in the evening to feed, using their keen sense of smell to find food. Depending on the habitat, pig-footed bandicoots used a variety of shelters to hide from predators and for sleeping. John Gilbert found a nest site near Northam, Western Australia, that he described as greatly resembling those made by quenda and marl, but with more leaves. In wooded areas and grasslands, these ranged from hollow logs to nests made out of grass, while in arid, treeless country, this animal dug short, straight burrows with a nest at the end.

From surviving eyewitness reports and analyses of gut contents, dentition, and gut structure of museum specimens,  pig-footed bandicoots apparently were the most herbivorous of the peramelemorphs; analysis based on dental morphology and tooth wear are consistent with a predominately plant-based diet. Captive specimens were fond of meat, and Aborigines reported that they ate grasshoppers, ants, and termites, the bulk of their diet was almost certainly leaves, roots, and grasses. In captivity, they drank "a good deal of water".

Tim Flannery suggests that breeding occurred between May and June and that twins may have been the norm for this species. From the size of its pouch and comparison with other marsupials of this size, pig-footed bandicoots likely did not carry more than four young per litter.
Correspondence to Ludwig Glauert, reporting its disappearance some decades earlier, suggested that the animal was extremely delicate and would die if caught and mishandled.

References

Extinct mammals of Australia
Peramelemorphs
Extinct marsupials
Mammal extinctions since 1500
Marsupial genera
Taxa named by William Ogilby

Chaeropus


Candidplatz is an U-Bahn station in Munich on the U1 line of the Munich U-Bahn system. The station is named for the Flemish mannerist painter Peter Candid, who entered employ in Munich in 1586, producing notable artworks for the Munich Residenz. The station is notable for the decorative scheme applied to the outer walls, which evoke a rainbow.

See also
List of Munich U-Bahn stations

References

Munich U-Bahn stations
Railway stations in Germany opened in 1997

Candidplatz station


The epicenter (), epicentre, or epicentrum in seismology is the point on the Earth's surface directly above a hypocenter or focus, the point where an earthquake or an underground explosion originates.

Determination

The primary purpose of a seismometer is to locate the initiating points of earthquake epicenters. The secondary purpose, of determining the 'size' or magnitude must be calculated after the precise location is known.

The earliest seismographs were designed to give a sense of the direction of the first motions from an earthquake. The Chinese frog seismograph would have dropped its ball in the general compass direction of the earthquake, assuming a strong positive pulse.  We now know that first motions can be in almost any direction depending on the type of initiating rupture (focal mechanism).

The first refinement that allowed a more precise determination of the location was the use of a time scale. Instead of merely noting, or recording, the absolute motions of a pendulum, the displacements were plotted on a moving graph, driven by a clock mechanism. This was the first seismogram, which allowed precise timing of the first ground motion, and an accurate plot of subsequent motions.

From the first seismograms, as seen in the figure, it was noticed that the trace was divided into two major portions. The first seismic wave to arrive was the P-wave, followed closely by the S-wave. Knowing the relative 'velocities of propagation', it was a simple matter to calculate the distance of the earthquake.

One seismograph would give the distance, but that could be plotted as a circle, with an infinite number of possibilities. Two seismographs would give two intersecting circles, with two possible locations. Only with a third seismograph would there be a precise location.

Modern earthquake location still requires a minimum of three seismometers. Most likely, there are many, forming a seismic array. The emphasis is on precision since much can be learned about the fault mechanics and seismic hazard, if the locations can be determined to be within a kilometer or two, for small earthquakes. For this, computer programs use an iterative process, involving a 'guess and correction' algorithm. As well, a very good model of the local crustal velocity structure is required: seismic velocities vary with the local geology. For P-waves, the relation between velocity and bulk density of the medium has been quantified in Gardner's relation.

Surface damage
Before the instrumental period of earthquake observation, the epicenter was thought to be the location where the greatest damage occurred, but the subsurface fault rupture may be long and spread surface damage across the entire rupture zone. As an example, in the magnitude 7.9 Denali earthquake of 2002 in Alaska, the epicenter was at the western end of the rupture, but the greatest damage was about  away at the eastern end. Focal depths of earthquakes occurring in continental crust mostly range from . Continental earthquakes below  are rare whereas in subduction zone earthquakes can originate at depths deeper than .

Epicentral distance

During an earthquake, seismic waves propagates in all directions from the hypocenter. Seismic shadowing occurs on the opposite side of the Earth from the earthquake epicenter because the planet's liquid outer core refracts the longitudinal or compressional (P-waves) while it absorbs the transverse or shear waves (S-waves).  Outside the seismic shadow zone, both types of wave can be detected but, because of their different velocities and paths through the Earth, they arrive at different times. By measuring the time difference on any seismograph and the distance on a travel-time graph on which the P-wave and S-wave have the same separation, geologists can calculate the distance to the quake's epicenter. This distance is called the epicentral distance, commonly measured in ° (degrees) and denoted as Δ (delta) in seismology. The Láska's empirical rule provides an approximation of epicentral distance in the range of 2 000 − 10 000 km.

Once distances from the epicenter have been calculated from at least three seismographic measuring stations, the point can be located, using trilateration.

Epicentral distance is also used in calculating seismic magnitudes as developed by Richter and Gutenberg.

Fault rupture

The point at which fault slipping begins is referred to as the focus of the earthquake. The fault rupture begins at the focus and then expands along the fault surface. The rupture stops where the stresses become insufficient to continue breaking the fault (because the rocks are stronger) or where the rupture enters ductile material. The magnitude of an earthquake is related to the total area of its fault rupture. Most earthquakes are small, with rupture dimensions less than the depth of the focus so the rupture doesn't break the surface, but in high magnitude, destructive earthquakes, surface breaks are common. Fault ruptures in large earthquakes can extend for more than . When a fault ruptures unilaterally (with the epicenter at or near the end of the fault break) the waves are stronger in one direction along the fault.

Macroseismic epicenter
The macroseismic epicenter is the best estimate of the location of the epicenter derived without instrumental data. This may be estimated using intensity data, information about foreshocks and aftershocks, knowledge of local fault systems or extrapolations from data regarding similar earthquakes. For historical earthquakes that have not been instrumentally recorded, only a macroseismic epicenter can be given.

Etymology
The word is derived from the Neo-Latin noun epicentrum, the latinisation of the ancient Greek adjective ἐπίκεντρος (), "occupying a cardinal point, situated on a centre", from ἐπί (epi) "on, upon, at" and κέντρον (kentron) "centre". The term was coined by the Irish seismologist Robert Mallet.

It is also used to mean "center of activity", as in "Travel is restricted in the Chinese province thought to be the epicentre of the SARS outbreak." Garner's Modern American Usage gives several examples of use in which "epicenter" is used to mean "center". Garner also refers to a William Safire article in which Safire quotes a geophysicist as attributing the use of the term to "spurious erudition on the part of writers combined with scientific illiteracy on the part of copy editors". Garner has speculated that these misuses may just be "metaphorical descriptions of focal points of unstable and potentially destructive environments."

References

Seismology
Geometric centers
Geographic position

Epicenter


Atla (1886) is a fantasy novel by Ann Eliza Smith. It is a tale about the discovery of the Atlantis civilization by the Phoenicians.

Plot
As the story opens, the fierce, barbaric empire of Atlantis is ruled by King Kron. His brother Thalok is high priest of the bloody state cult, which demands human sacrifices, hearts torn out in Aztec fashion. Kron's wife has given birth to a daughter, who is called Astera and at this same time a beautiful blond woman is shipwrecked on the Atlantean coast. She dies after giving birth to a girl who grows up as the bosom companion to Astera. King Kron names the orphaned child Atla.

When the young women are about twenty years old, Prince Herekla of Cacara in Phoenicia invents the magnetic compass. Herekla derives the basic idea from Chinese merchants. King Kron recognizes the power of Phoenicia, and is willing to betroth his daughter to Herekla. Herekla comes to Atlantis to accept his bride. Love, however, does not honor contracts, for Herekla and Atla fall in love. Astera, in turn, falls in love with Zemar, the virtuous son of the vile, ruthless priest Thalok.

Thalok, who has long lusted for the throne and the gorgeous blond Atla, murders Kron, usurps the crown, and is about to start his persecutions. But as the four lovers flee Atlantis in various ways (agreeing to meet at the island of Surchi), Atlantis sinks beneath the sea. Thalok, in pursuit of the refugees, is killed by a poisonous serpent, the pet of an amorous sorceress-lover he had discarded.

The lovers now pair off. Zemar and Astera go to found a new Atlantis in the west, presumably Central America, while Herekla and Atla make their way to Phoenicia. As a Magian explains, when moral virtue is dead, physical changes take place, with catastrophe the result. This is why Atlantis sank.

1886 American novels
1886 fantasy novels
American fantasy novels
Novels set in Atlantis
Harper & Brothers books
Phoenicia in fiction
Novels about cults
Fiction about human sacrifice

Atla: A Story of the Lost Island


In physical cosmology and astronomy, dark energy is an unknown form of energy that affects the universe on the largest scales. Its primary effect is to drive the accelerating expansion of the universe. Assuming that the lambda-CDM model of cosmology is correct, dark energy is the dominant component of the universe, contributing 68% of the total energy in the present-day observable universe while dark matter and ordinary (baryonic) matter contribute 26% and 5%, respectively, and other components such as neutrinos and photons are nearly negligible. Dark energy's density is very low:  (≈), much less than the density of ordinary matter or dark matter within galaxies. However, it dominates the universe's mass–energy content because it is uniform across space.

The first observational evidence for dark energy's existence came from measurements of supernovae. Type 1A supernovae have constant luminosity, which means they can be used as accurate distance measures. Comparing this distance to the redshift (which measures the speed at which the supernova is receding) shows that the universe's expansion is accelerating. Prior to this observation, scientists thought that the gravitational attraction of matter and energy in the universe would cause the universe's expansion to slow over time. Since the discovery of accelerating expansion, several independent lines of evidence have been discovered that support the existence of dark energy.

The exact nature of dark energy remains a mystery, and explanations abound. The main candidates are a cosmological constant (representing a constant energy density filling space homogeneously) and scalar fields (dynamic quantities having energy densities that vary in time and space) such as quintessence or moduli. A cosmological constant would remain constant across time and space, while scalar fields can vary. Yet other possibilities are interacting dark energy, an observational effect, and cosmological coupling (see the Theories of Dark Energy section).

History of discovery and previous speculation

Einstein's cosmological constant
The "cosmological constant" is a constant term that can be added to Einstein field equations of general relativity. If considered as a "source term" in the field equation, it can be viewed as equivalent to the mass of empty space (which conceptually could be either positive or negative), or "vacuum energy".

The cosmological constant was first proposed by Einstein as a mechanism to obtain a solution to the gravitational field equation that would lead to a static universe, effectively using dark energy to balance gravity. Einstein gave the cosmological constant the symbol Λ (capital lambda). Einstein stated that the cosmological constant required that 'empty space takes the role of gravitating negative masses which are distributed all over the interstellar space'.

The mechanism was an example of fine-tuning, and it was later realized that Einstein's static universe would not be stable: local inhomogeneities would ultimately lead to either the runaway expansion or contraction of the universe. The equilibrium is unstable: if the universe expands slightly, then the expansion releases vacuum energy, which causes yet more expansion. Likewise, a universe which contracts slightly will continue contracting. According to Einstein, "empty space" can possess its own energy. Because this energy is a property of space itself, it would not be diluted as space expands. As more space comes into existence, more of this energy-of-space would appear, thereby causing accelerated expansion. These sorts of disturbances are inevitable, due to the uneven distribution of matter throughout the universe. Further, observations made by Edwin Hubble in 1929 showed that the universe appears to be expanding and is not static. Einstein reportedly referred to his failure to predict the idea of a dynamic universe, in contrast to a static universe, as his greatest blunder.

Inflationary dark energy
Alan Guth and Alexei Starobinsky proposed in 1980 that a negative pressure field, similar in concept to dark energy, could drive cosmic inflation in the very early universe. Inflation postulates that some repulsive force, qualitatively similar to dark energy, resulted in an enormous and exponential expansion of the universe slightly after the Big Bang. Such expansion is an essential feature of most current models of the Big Bang. However, inflation must have occurred at a much higher (negative) energy density than the dark energy we observe today, and inflation is thought to have completely ended when the universe was just a fraction of a second old. It is unclear what relation, if any, exists between dark energy and inflation. Even after inflationary models became accepted, the cosmological constant was thought to be irrelevant to the current universe.

Nearly all inflation models predict that the total (matter+energy) density of the universe should be very close to the critical density. During the 1980s, most cosmological research focused on models with critical density in matter only, usually 95% cold dark matter (CDM) and 5% ordinary matter (baryons). These models were found to be successful at forming realistic galaxies and clusters, but some problems appeared in the late 1980s: in particular, the model required a value for the Hubble constant lower than preferred by observations, and the model under-predicted observations of large-scale galaxy clustering. These difficulties became stronger after the discovery of anisotropy in the cosmic microwave background by the COBE spacecraft in 1992, and several modified CDM models came under active study through the mid-1990s: these included the Lambda-CDM model and a mixed cold/hot dark matter model. The first direct evidence for dark energy came from supernova observations in 1998 of accelerated expansion in Riess et al. and in Perlmutter et al., and the Lambda-CDM model then became the leading model. Soon after, dark energy was supported by independent observations: in 2000, the BOOMERanG and Maxima cosmic microwave background experiments observed the first acoustic peak in the cosmic microwave background, showing that the total (matter+energy) density is close to 100% of critical density. Then in 2001, the 2dF Galaxy Redshift Survey gave strong evidence that the matter density is around 30% of critical. The large difference between these two supports a smooth component of dark energy making up the difference. Much more precise measurements from WMAP in 2003–2010 have continued to support the standard model and give more accurate measurements of the key parameters.

The term "dark energy", echoing Fritz Zwicky's "dark matter" from the 1930s, was coined by Michael Turner in 1998.

Change in expansion over time

High-precision measurements of the expansion of the universe are required to understand how the expansion rate changes over time and space. In general relativity, the evolution of the expansion rate is estimated from the curvature of the universe and the cosmological equation of state (the relationship between temperature, pressure, and combined matter, energy, and vacuum energy density for any region of space). Measuring the equation of state for dark energy is one of the biggest efforts in observational cosmology today. Adding the cosmological constant to cosmology's standard FLRW metric leads to the Lambda-CDM model, which has been referred to as the "standard model of cosmology" because of its precise agreement with observations.

As of 2013, the Lambda-CDM model is consistent with a series of increasingly rigorous cosmological observations, including the Planck spacecraft and the Supernova Legacy Survey. First results from the SNLS reveal that the average behavior (i.e., equation of state) of dark energy behaves like Einstein's cosmological constant to a precision of 10%. Recent results from the Hubble Space Telescope Higher-Z Team indicate that dark energy has been present for at least 9 billion years and during the period preceding cosmic acceleration.

Nature
The nature of dark energy is more hypothetical than that of dark matter, and many things about it remain in the realm of speculation. Dark energy is thought to be very homogeneous and not dense, and is not known to interact through any of the fundamental forces other than gravity. Since it is rarefied and un-massive—roughly 10−27 kg/m3—it is unlikely to be detectable in laboratory experiments. The reason dark energy can have such a profound effect on the universe, making up 68% of universal density in spite of being so dilute, is that it is believed to uniformly fill otherwise empty space.

The vacuum energy, that is, the particle-antiparticle pairs generated and mutually annihilated within a time frame in accord with Heisenberg's uncertainty principle in the energy-time formulation, has been often invoked as the main contribution to dark energy. The mass–energy equivalence postulated by general relativity implies that the vacuum energy should exert a gravitational force. Hence, the vacuum energy is expected to contribute to the cosmological constant, which in turn impinges on the accelerated expansion of the universe. However, the cosmological constant problem asserts that there is a huge disagreement between the observed values of vacuum energy density and the theoretical large value of zero-point energy obtained by quantum field theory; the problem remains unresolved.

Independently of its actual nature, dark energy would need to have a strong negative pressure to explain the observed acceleration of the expansion of the universe. According to general relativity, the pressure within a substance contributes to its gravitational attraction for other objects just as its mass density does. This happens because the physical quantity that causes matter to generate gravitational effects is the stress–energy tensor, which contains both the energy (or matter) density of a substance and its pressure. In the Friedmann–Lemaître–Robertson–Walker metric, it can be shown that a strong constant negative pressure (i.e., tension) in all the universe causes an acceleration in the expansion if the universe is already expanding, or a deceleration in contraction if the universe is already contracting. This accelerating expansion effect is sometimes labeled "gravitational repulsion".

Technical definition

In standard cosmology, there are three components of the universe: matter, radiation, and dark energy. Matter is anything whose energy density scales with the inverse cube of the scale factor, i.e., , while radiation is anything which scales to the inverse fourth power of the scale factor (). This can be understood intuitively: for an ordinary particle in a cube-shaped box, doubling the length of an edge of the box decreases the density (and hence energy density) by a factor of eight (23). For radiation, the decrease in energy density is greater, because an increase in spatial distance also causes a redshift.

The final component is dark energy: it is an intrinsic property of space and has a constant energy density, regardless of the dimensions of the volume under consideration (). Thus, unlike ordinary matter, it is not diluted by the expansion of space.

Evidence of existence
The evidence for dark energy is indirect but comes from three independent sources:
 Distance measurements and their relation to redshift, which suggest the universe has expanded more in the latter half of its life.
 The theoretical need for a type of additional energy that is not matter or dark matter to form the observationally flat universe (absence of any detectable global curvature).
 Measures of large-scale wave patterns of mass density in the universe.

Supernovae

In 1998, the High-Z Supernova Search Team published observations of Type Ia ("one-A") supernovae. In 1999, the Supernova Cosmology Project followed by suggesting that the expansion of the universe is accelerating. The 2011 Nobel Prize in Physics was awarded to Saul Perlmutter, Brian P. Schmidt, and Adam G. Riess for their leadership in the discovery.

Since then, these observations have been corroborated by several independent sources. Measurements of the cosmic microwave background, gravitational lensing, and the large-scale structure of the cosmos, as well as improved measurements of supernovae, have been consistent with the Lambda-CDM model. Some people argue that the only indications for the existence of dark energy are observations of distance measurements and their associated redshifts. Cosmic microwave background anisotropies and baryon acoustic oscillations serve only to demonstrate that distances to a given redshift are larger than would be expected from a "dusty" Friedmann–Lemaître universe and the local measured Hubble constant.

Supernovae are useful for cosmology because they are excellent standard candles across cosmological distances. They allow researchers to measure the expansion history of the universe by looking at the relationship between the distance to an object and its redshift, which gives how fast it is receding from us. The relationship is roughly linear, according to Hubble's law. It is relatively easy to measure redshift, but finding the distance to an object is more difficult. Usually, astronomers use standard candles: objects for which the intrinsic brightness, or absolute magnitude, is known. This allows the object's distance to be measured from its actual observed brightness, or apparent magnitude. Type Ia supernovae are the best-known standard candles across cosmological distances because of their extreme and consistent luminosity.

Recent observations of supernovae are consistent with a universe made up 71.3% of dark energy and 27.4% of a combination of dark matter and baryonic matter.

Large-scale structure
The theory of large-scale structure, which governs the formation of structures in the universe (stars, quasars, galaxies and galaxy groups and clusters), also suggests that the density of matter in the universe is only 30% of the critical density.

A 2011 survey, the WiggleZ galaxy survey of more than 200,000 galaxies, provided further evidence towards the existence of dark energy, although the exact physics behind it remains unknown. The WiggleZ survey from the Australian Astronomical Observatory scanned the galaxies to determine their redshift. Then, by exploiting the fact that baryon acoustic oscillations have left voids regularly of ≈150 Mpc diameter, surrounded by the galaxies, the voids were used as standard rulers to estimate distances to galaxies as far as 2,000 Mpc (redshift 0.6), allowing for accurate estimate of the speeds of galaxies from their redshift and distance. The data confirmed cosmic acceleration up to half of the age of the universe (7 billion years) and constrain its inhomogeneity to 1 part in 10. This provides a confirmation to cosmic acceleration independent of supernovae.

Cosmic microwave background

The existence of dark energy, in whatever form, is needed to reconcile the measured geometry of space with the total amount of matter in the universe. Measurements of cosmic microwave background anisotropies indicate that the universe is close to flat. For the shape of the universe to be flat, the mass–energy density of the universe must be equal to the critical density. The total amount of matter in the universe (including baryons and dark matter), as measured from the cosmic microwave background spectrum, accounts for only about 30% of the critical density. This implies the existence of an additional form of energy to account for the remaining 70%. The Wilkinson Microwave Anisotropy Probe (WMAP) spacecraft seven-year analysis estimated a universe made up of 72.8% dark energy, 22.7% dark matter, and 4.5% ordinary matter.
Work done in 2013 based on the Planck spacecraft observations of the cosmic microwave background gave a more accurate estimate of 68.3% dark energy, 26.8% dark matter, and 4.9% ordinary matter.

Late-time integrated Sachs–Wolfe effect
Accelerated cosmic expansion causes gravitational potential wells and hills to flatten as photons pass through them, producing cold spots and hot spots on the cosmic microwave background aligned with vast supervoids and superclusters. This so-called late-time Integrated Sachs–Wolfe effect (ISW) is a direct signal of dark energy in a flat universe. It was reported at high significance in 2008 by Ho et al. and Giannantonio et al.

Observational Hubble constant data
A new approach to test evidence of dark energy through observational Hubble constant data (OHD), also known as cosmic chronometers, has gained significant attention in recent years.

The Hubble constant, H(z), is measured as a function of cosmological redshift. OHD directly tracks the expansion history of the universe by taking passively evolving early-type galaxies as "cosmic chronometers". From this point, this approach provides standard clocks in the universe. The core of this idea is the measurement of the differential age evolution as a function of redshift of these cosmic chronometers. Thus, it provides a direct estimate of the Hubble parameter

The reliance on a differential quantity,  brings more information and is appealing for computation: It can minimize many common issues and systematic effects. Analyses of supernovae and baryon acoustic oscillations (BAO) are based on integrals of the Hubble parameter, whereas  measures it directly. For these reasons, this method has been widely used to examine the accelerated cosmic expansion and study properties of dark energy.

Theories of dark energy
Dark energy's status as a hypothetical force with unknown properties makes it an active target of research. The problem is attacked from a variety of angles, such as modifying the prevailing theory of gravity (general relativity), attempting to pin down the properties of dark energy, and finding alternative ways to explain the observational data.

Cosmological constant

The simplest explanation for dark energy is that it is an intrinsic, fundamental energy of space. This is the cosmological constant, usually represented by the Greek letter  (Lambda, hence the name Lambda-CDM model). Since energy and mass are related according to the equation  Einstein's theory of general relativity predicts that this energy will have a gravitational effect. It is sometimes called a vacuum energy because it is the energy density of empty space – a vacuum.

A major outstanding problem is that the same quantum field theories predict a huge cosmological constant, about 120 orders of magnitude too large. This would need to be almost, but not exactly, cancelled by an equally large term of the opposite sign.

Some supersymmetric theories require a cosmological constant that is exactly zero. Also, it is unknown if there is a metastable vacuum state in string theory with a positive cosmological constant, and it has been conjectured by Ulf Danielsson et al. that no such state exists. This conjecture would not rule out other models of dark energy, such as quintessence, that could be compatible with string theory.

Quintessence

In quintessence models of dark energy, the observed acceleration of the scale factor is caused by the potential energy of a dynamical field, referred to as quintessence field. Quintessence differs from the cosmological constant in that it can vary in space and time. In order for it not to clump and form structure like matter, the field must be very light so that it has a large Compton wavelength. In the simplest scenarios, the quintessence field has a canonical kinetic term, is minimally coupled to gravity, and does not feature higher order operations in its Lagrangian.

No evidence of quintessence is yet available, nor has it been ruled out. It generally predicts a slightly slower acceleration of the expansion of the universe than the cosmological constant. Some scientists think that the best evidence for quintessence would come from violations of Einstein's equivalence principle and variation of the fundamental constants in space or time. Scalar fields are predicted by the Standard Model of particle physics and string theory, but an analogous problem to the cosmological constant problem (or the problem of constructing models of cosmological inflation) occurs: renormalization theory predicts that scalar fields should acquire large masses.

The coincidence problem asks why the acceleration of the Universe began when it did. If acceleration began earlier in the universe, structures such as galaxies would never have had time to form, and life, at least as we know it, would never have had a chance to exist. Proponents of the anthropic principle view this as support for their arguments. However, many models of quintessence have a so-called "tracker" behavior, which solves this problem. In these models, the quintessence field has a density which closely tracks (but is less than) the radiation density until matter–radiation equality, which triggers quintessence to start behaving as dark energy, eventually dominating the universe. This naturally sets the low energy scale of the dark energy.

In 2004, when scientists fit the evolution of dark energy with the cosmological data, they found that the equation of state had possibly crossed the cosmological constant boundary (w = −1) from above to below. A no-go theorem has been proved that this scenario requires models with at least two types of quintessence. This scenario is the so-called Quintom scenario.

Some special cases of quintessence are phantom energy, in which the energy density of quintessence actually increases with time, and k-essence (short for kinetic quintessence) which has a non-standard form of kinetic energy such as a negative kinetic energy. They can have unusual properties: phantom energy, for example, can cause a Big Rip.

A group of researchers argued in 2021 that observations of the Hubble tension may imply that only quintessence models with a nonzero coupling constant are viable.

Interacting dark energy
This class of theories attempts to come up with an all-encompassing theory of both dark matter and dark energy as a single phenomenon that modifies the laws of gravity at various scales. This could, for example, treat dark energy and dark matter as different facets of the same unknown substance, or postulate that cold dark matter decays into dark energy. Another class of theories that unifies dark matter and dark energy are suggested to be covariant theories of modified gravities. These theories alter the dynamics of spacetime such that the modified dynamics stems to what have been assigned to the presence of dark energy and dark matter. Dark energy could in principle interact not only with the rest of the dark sector, but also with ordinary matter. However, cosmology alone is not sufficient to effectively constrain the strength of the coupling between dark energy and baryons, so that other indirect techniques or laboratory searches have to be adopted. It was briefly theorized in the early 2020s that excess observed in the XENON1T detector in Italy may have been caused by a chameleon model of dark energy, but further experiments disproved this possibility.

Variable dark energy models
The density of dark energy might have varied in time during the history of the universe. Modern observational data allows us to estimate the present density of dark energy. Using baryon acoustic oscillations, it is possible to investigate the effect of dark energy in the history of the Universe, and constrain parameters of the equation of state of dark energy. To that end, several models have been proposed. One of the most popular models is the Chevallier–Polarski–Linder model (CPL). Some other common models are (Barboza & Alcaniz. 2008), (Jassal et al. 2005), (Wetterich. 2004), and (Oztas et al. 2018).

Observational skepticism
Some alternatives to dark energy, such as inhomogeneous cosmology, aim to explain the observational data by a more refined use of established theories. In this scenario, dark energy doesn't actually exist, and is merely a measurement artifact. For example, if we are located in an emptier-than-average region of space, the observed cosmic expansion rate could be mistaken for a variation in time, or acceleration. A different approach uses a cosmological extension of the equivalence principle to show how space might appear to be expanding more rapidly in the voids surrounding our local cluster. While weak, such effects considered cumulatively over billions of years could become significant, creating the illusion of cosmic acceleration, and making it appear as if we live in a Hubble bubble. Yet other possibilities are that the accelerated expansion of the universe is an illusion caused by the relative motion of us to the rest of the universe, or that the statistical methods employed were flawed. A laboratory direct detection attempt failed to detect any force associated with dark energy.

Observational skepticism explanations of dark energy have generally not gained much traction among cosmologists. For example, a paper that suggested the anisotropy of the local Universe has been misrepresented as dark energy was quickly countered by another paper claiming errors in the original paper. Another study questioning the essential assumption that the luminosity of Type Ia supernovae does not vary with stellar population age was also swiftly rebutted by other cosmologists.

As a general relativistic effect due to black holes
This theory was formulated by University of Hawaiʻi at Mānoa researchers in February 2023. The idea is that if one requires the Kerr metric (which describes rotating black holes) to asymptote to the Friedmann-Robertson-Walker metric (which describes the isotropic and homogeneous universe that is the basic assumption of modern cosmology), then one finds that black holes gain mass as the universe expands. The rate is measured to be , where a is the scale factor. This particular rate means that the energy density of black holes remain constant over time, mimicking dark energy (see Dark_energy#Technical_definition). The theory is called "cosmological coupling" because the black holes couple to a cosmological requirement. Other astrophysicists are skeptical, with a variety of papers claiming that the theory fails to explain other observations.

Other mechanism driving acceleration

Modified gravity

The evidence for dark energy is heavily dependent on the theory of general relativity. Therefore, it is conceivable that a modification to general relativity also eliminates the need for dark energy. There are many such theories, and research is ongoing. The measurement of the speed of gravity in the first gravitational wave measured by non-gravitational means (GW170817) ruled out many modified gravity theories as explanations to dark energy.

Astrophysicist Ethan Siegel states that, while such alternatives gain mainstream press coverage, almost all professional astrophysicists are confident that dark energy exists, and that none of the competing theories successfully explain observations to the same level of precision as standard dark energy.

Implications for the fate of the universe
Cosmologists estimate that the acceleration began roughly 5 billion years ago. Before that, it is thought that the expansion was decelerating, due to the attractive influence of matter. The density of dark matter in an expanding universe decreases more quickly than dark energy, and eventually the dark energy dominates. Specifically, when the volume of the universe doubles, the density of dark matter is halved, but the density of dark energy is nearly unchanged (it is exactly constant in the case of a cosmological constant).

Projections into the future can differ radically for different models of dark energy. For a cosmological constant, or any other model that predicts that the acceleration will continue indefinitely, the ultimate result will be that galaxies outside the Local Group will have a line-of-sight velocity that continually increases with time, eventually far exceeding the speed of light. This is not a violation of special relativity because the notion of "velocity" used here is different from that of velocity in a local inertial frame of reference, which is still constrained to be less than the speed of light for any massive object (see Uses of the proper distance for a discussion of the subtleties of defining any notion of relative velocity in cosmology). Because the Hubble parameter is decreasing with time, there can actually be cases where a galaxy that is receding from us faster than light does manage to emit a signal which reaches us eventually.

However, because of the accelerating expansion, it is projected that most galaxies will eventually cross a type of cosmological event horizon where any light they emit past that point will never be able to reach us at any time in the infinite future because the light never reaches a point where its "peculiar velocity" toward us exceeds the expansion velocity away from us (these two notions of velocity are also discussed in Uses of the proper distance). Assuming the dark energy is constant (a cosmological constant), the current distance to this cosmological event horizon is about 16 billion light years, meaning that a signal from an event happening at present would eventually be able to reach us in the future if the event were less than 16 billion light years away, but the signal would never reach us if the event were more than 16 billion light years away.

As galaxies approach the point of crossing this cosmological event horizon, the light from them will become more and more redshifted, to the point where the wavelength becomes too large to detect in practice and the galaxies appear to vanish completely (see Future of an expanding universe). Planet Earth, the Milky Way, and the Local Group of galaxies of which the Milky Way is a part, would all remain virtually undisturbed as the rest of the universe recedes and disappears from view. In this scenario, the Local Group would ultimately suffer heat death, just as was hypothesized for the flat, matter-dominated universe before measurements of cosmic acceleration.

There are other, more speculative ideas about the future of the universe. The phantom energy model of dark energy results in divergent expansion, which would imply that the effective force of dark energy continues growing until it dominates all other forces in the universe. Under this scenario, dark energy would ultimately tear apart all gravitationally bound structures, including galaxies and solar systems, and eventually overcome the electrical and nuclear forces to tear apart atoms themselves, ending the universe in a "Big Rip". On the other hand, dark energy might dissipate with time or even become attractive. Such uncertainties leave open the possibility of gravity eventually prevailing and lead to a universe that contracts in on itself in a "Big Crunch", or that there may even be a dark energy cycle, which implies a cyclic model of the universe in which every iteration (Big Bang then eventually a Big Crunch) takes about a trillion (1012) years. While none of these are supported by observations, they are not ruled out.

In philosophy of science
The astrophysicist David Merritt identifies dark energy as an example of an "auxiliary hypothesis", an ad hoc postulate that is added to a theory in response to observations that falsify it. He argues that the dark energy hypothesis is a conventionalist hypothesis, that is, a hypothesis that adds no empirical content and hence is unfalsifiable in the sense defined by Karl Popper. However, his opinion doesn't seem to be consensus and is at odds with the history of cosmology.

See also

 Conformal gravity
 Dark Energy Spectroscopic Instrument
 Dark matter
 De Sitter invariant special relativity
 Illustris project
 Inhomogeneous cosmology
 Joint Dark Energy Mission
 Negative mass
 Quintessence: The Search for Missing Mass in the Universe
 Dark Energy Survey
 Quantum vacuum state

Notes

References

External links
 Euclid ESA Satellite, a mission to map the geometry of the dark universe
 "Surveying the dark side"

1998 neologisms
Dark concepts in astrophysics
Energy (physics)
Physical cosmology
Concepts in astronomy
Unsolved problems in astronomy
Unsolved problems in physics

Dark energy


(, ), which means , is the motto of the monarch of the United Kingdom. It appears on a scroll beneath the shield of the version of the coat of arms of the United Kingdom. The motto is said to have first been used by Richard I (1157–1199) as a battle cry and presumed to be a reference to his French ancestry (indeed he spoke French and Occitan but knew only basic English) and the concept of the divine right of the monarch to govern. It was adopted as the royal motto of England by King Henry V (1386–1422) with the phrase "and my right" referring to his claim by descent to the French crown.

Language
The motto is French for "God and my right", meaning that the king is "" ("King of England by the grace of God"). It is used to imply that the monarch of a nation has a God-given (divine) right to rule.

It was not unusual for the royal coat of arms of the Kingdom of England to have a French rather than English motto, given that Norman French was the primary language of the English Royal Court and ruling class following the rule of William the Conqueror of Normandy and later the Plantagenets. Another Old French phrase also appears in the full achievement of the Royal Arms: the motto of the Order of the Garter,  ("Shamed be the one who thinks ill of it"), appears on a representation of a garter behind the shield. Modern French spelling has changed  to , but the motto has not been updated.

Other translations
 has been translated in several ways, including "God and my right", "God and my right hand", "God and my lawful right", and "God and my right shall me defend".

The literal translation of  is "God and my right". However, Kearsley's Complete Peerage, published in 1799, translates it to mean "God and my right hand" (in standard French that would be , not ). The Kearsley volume appeared during publication of the 1st edition (1796–1808) of the German , which emphasised the raising of the "right hand" during installations and coronations of German Kings.

Diderot's  lists the motto as , which Susan Emanuel translated as "God is my right".

Use as royal motto

 has generally been used as the motto of English monarchs, and later by British monarchs, since being adopted by Henry V. It was first used as a battle cry by King Richard I in 1198 at the Battle of Gisors, when he defeated the forces of Philip II of France and after he made it his motto. Medieval Europeans did not believe that victory necessarily went to the side with the better army, but (as they also viewed personal trial by combat) to the side that God viewed with favour. Hence Richard wrote after his victory "It is not us who have done it but God and our right through us". So after his victories on the crusades "Richard was speaking what he believed to be the truth when he told the Holy Roman Emperor: 'I am born of a rank which recognises no superior but God.

Alternatively, the Royal Arms may depict a monarch's personal motto. For example, Elizabeth I and Queen Anne's often displayed ; Latin for "Always the same", and James I's depicted , Latin for "Blessed are the peacemakers".

Current usages

 has been adopted along with the rest of the Royal Coat of Arms by The Times as part of its masthead. When it incorporated the Coat of Arms in 1875, half the newspapers in London were also doing so. Since 1982 the paper abandoned the use of the current Royal Coat of Arms and returned to using the Hanoverian coat of arms of 1785.

Versions of the Coat of Arms, with the motto, is used by various newspapers, including Melbourne's The Age in Australia, Christchurch's The Press in New Zealand, the UK's Daily Mail, and Canada's Victoria Times Colonist. It is also used in Hardwick Hall in England on the fireplace of The High Great Chamber, also known as the Presence Chamber, though there it reads , God is my right. instead creating an additional 'ES' monogram. The extra E and S are a superimposition on the original E. This was added at a later date after the original writing was put up; to deface the Royal Arms would have been very dangerous, hence it was added later.

It is also found on the official belt buckle of the Jamaica Constabulary Force; the front page of a British passport; the rank slide of a warrant officer in the British and other Commonwealth armed forces; the arms of the Supreme Court of Victoria and Supreme Court of New South Wales; and the crests of Hawthorn Rowing Club in Melbourne, Australia, Nottingham Law School, and Sherborne School.

The coined phrase was also used by Michael Jackson at his Neverland Ranch's front gates. The crest on the main gates carried the Royal Coat of Arms of the United Kingdom, along with the phrase at the bottom.

The motto was formerly included in a scroll on the Western Australia Police Force coat of arms, before being replaced with "Protect and Serve" when the organisation changed its name from Western Australia Police Force to Western Australia Police Service.

It is the motto of Queen Elizabeth's School, Barnet.

It is the motto of the Royal Grammar School, Guildford, England.
It is the motto of several, but not all, schools within the King Edward VI School Foundation, Birmingham, England including:

 Fee Paying:      King Edward's School
 Selective:          King Edward VI Aston School,  King Edward VI Camp Hill School for Girls,  King Edward VI Five Ways School,  King Edward VI Handsworth School for Girls

It is also found on the Old Customs House in Sydney, Australia. The Royal Coat of Arms is intricately carved in sandstone, located above the main entry pediment.

Variants

The Hearts of Oak, a revolutionary New York militia commanded by Alexander Hamilton, wore badges of red tin hearts on their jackets with the words "God and Our Right".

The phrase was the inspiration for a joke motto by The Beatles, Duit on Mon Dei ("Do it on Monday") and Harry Nilsson's 1975 album Duit on Mon Dei.

Prince Philip, Duke of Edinburgh, as consort of the British monarch, used a similar motto: "God Is My Help".

Henry Hudson in 1612 used the wording  (God is my right).

Other people considered the phrase  (God is my right) means he was direct sovereign and not vassal of any other king.

Another example of  is inscribed under the royal coat of arms on the over mantle of the High Great Chamber in Hardwick Hall, Derbyshire.

See also
 , the motto of the British monarch for use in Scotland
Nemo me impune lacessit, the motto of Scotland
 , the motto of the Prince of Wales

 List of national mottos

References

French words and phrases
British monarchy
National mottos
National symbols of the United Kingdom

Dieu et mon droit


Husayn ibn Hamdan ibn Hamdun ibn al-Harith al-Taghlibi () was an early member of the Hamdanid family, who distinguished himself as a general for the Abbasid Caliphate and played a major role in the Hamdanids' rise to power among the Arab tribes in the Jazira.

Husayn entered caliphal service in 895, and through his co-operation with the caliphal government, he established himself and his family as the leader of the Arabs and Kurds of the Jazira, leading his troops to successful campaigns against the Qarmatians, Dulafids and Tulunids over the next few years. As one of the most distinguished generals of the Abbasid Caliphate, he rose in power and influence until 908, when he was one of the leading conspirators in the abortive coup against Caliph al-Muqtadir. Although the coup failed and Husayn was forced to flee the capital, he soon secured a pardon and served as governor in Jibal, where he again distinguished himself in military operations in south-central Iran. In ca. 911, he was appointed governor in Mosul, where he remained until rising in revolt in 914/5, for reasons that are unclear. Defeated and captured in 916, he was imprisoned in Baghdad, where he was executed in 918. Through his influence, the family rose to high offices, beginning a long period during which Mosul and the entire Jazira were ruled by the Hamdanids. His nephews, Nasir al-Dawla and Sayf al-Dawla, went on to establish autonomous emirates in Mosul and Aleppo respectively.

Biography

Origin and early career

Husayn was a son of the Hamdanid family's patriarch, Hamdan ibn Hamdun. His family belonged to the Banu Taghlib tribe, established in the Jazira since before the Muslim conquests. In a pattern repeated across the Abbasid Caliphate, the Taghlibi leaders took advantage of the collapse of central caliphal authority during the decade-long Anarchy at Samarra  (861–870) to assert increasing control over their particular area, centred on Mosul. Hamdan established himself among the leading tribal leaders during this time, and led the resistance against caliphal attempts to restore direct control, even allying with the Kharijite rebels in the 880s. Finally, in 895 Caliph al-Mu'tadid launched a determined attack to recover the Jazira. Hamdan fled before the Caliph's advance and was captured after a long pursuit and thrown in prison.

Husayn, however, who had been entrusted with the fortress of Ardumusht on the left bank of the Tigris, chose to surrender it instead, and offered his services to the Caliph. He managed to capture the Kharijite leader Harun al-Shari, thereby bringing an end to the Kharijite revolt in the Jazira. In exchange he secured not only a pardon for his father, but also the lifting of a tribute that the Taghlib had been forced to pay, and the right to form a regiment of 500 Taghlibi cavalry at government expense. This was a major success, laying the groundwork for his own and his family's ascent to power. In the words of the Islamic scholar Hugh N. Kennedy, to the caliph he offered a group of experienced warriors under his own skilled and loyal leadership; to the Taghlib, and other people in the Jazira, he offered the prospect of salaries and booty; and to his own family military command and the opportunity of acquiring wealth in government services. It was in fact not as an independent tribal leader, but rather as an intermediary between government and the Arabs and Kurds of the Jazira that al-Husayn made the family fortune.

In Abbasid service

Husayn led his Taghlibi regiment with distinction over the next few years. He fought against the Dulafid Bakr ibn Abd al-Aziz ibn Ahmad ibn Abi Dulaf in the Jibal in 896. After 903 he played a decisive role in the campaigns of Muhammad ibn Sulayman al-Katib against the Qarmatians of the Syrian desert, where his experienced cavalry was crucial in countering the highly mobile Qarmatians. In 903 he participated in Muhammad's major victory over the Qarmatian leader al-Husayn ibn Zikrawayh, better known by his laqab of "Sahib al-Shama",  near Hama. The Qarmatian leaders fled to the desert, but were soon captured, and brought in triumph to Baghdad. Husayn then participated as commander of the vanguard in Muhammad's 904–905 campaign that ended the Tulunid dynasty and restored Syria and Egypt to direct caliphal control. Muhammad ibn Sulayman reportedly offered him the governorship of Egypt, but Husayn refused, preferring to return to Baghdad with the enormous booty he had collected.

On his return from Egypt, in 905–906, Husayn was sent against the Banu Kalb of Syria, who had risen in revolt at the instigation of the Qarmatians. Although he drove them into the desert, the Kalbis filled up the wells as they retreated, and he was unable to follow them. As a result, the rebels were able to reach the Lower Euphrates, where they defeated another Abbasid force at al-Qadisiyya and raided the hajj caravan of the Mecca pilgrims (late 906). In the end, the forces of the central government defeated the Qarmatians and drove them to flight. On their retreat back to Syria along the Euphrates, they were attacked and annihilated by Husayn in March/April 907. Although these victories did not entirely remove the Qarmatian threat—the Qarmatians based in Bahrayn continued to remain active and raided lower Iraq—they signalled the near-eradication of the sect from Syria. Husayn then subdued the remaining Kalbi rebels between the Euphrates and Aleppo, and in 907–908 confronted and drove back into Syria the Banu Tamim who had invaded the Jazira seeking pillage, defeating them near Khunasira.

By 908, this distinguished service had established Husayn as "one of the leading generals" (Kennedy) in the Caliphate, and enabled him to advance his own brothers to positions of power: they received various offices, the most important of which was the award of the governorship of Mosul to Husayn's brother Abu'l-Hayja Abdallah in 905. In December 908, Husayn became involved in a palace plot to depose the new Caliph, al-Muqtadir, in favour of the older Ibn al-Mu'tazz. Along with two others, on 17 December 908 he attacked and killed the vizier al-Abbas ibn al-Hasan al-Jarjara'i, who had endorsed al-Muqtadir's accession. The conspirators then sought to kill the young caliph as well, but the latter had barricaded himself in the Hasani Palace. Ibn al-Mu'tazz was proclaimed as caliph, and Husayn went to the palace to persuade al-Muqtadir to surrender. However, the unexpected resistance of the palace servants under the chamberlains Sawsan, Mu'nis al-Fahl and Mu'nis al-Khadim, and the plotters' indecision, doomed the coup. Al-Muqtadir prevailed, and Husayn fled from Baghdad to Mosul and to Balad. He then spent some time wandering with his followers across the Jazira. The caliph sent Husayn's own brother, Abu'l-Hayja Abdallah, to pursue him, but Husayn managed to surprise and defeat him. This success encouraged him to contact the new vizier, Ali ibn al-Furat, through the mediation of his brother Ibrahim. Although he had been a leading figure in the conspiracy, and most of the other participants in the coup were executed or imprisoned, Husayn succeeded in receiving a pardon. He was not welcomed back to Baghdad, however, but appointed governor of Qumm and Kashan in the Jibal.

As governor, he aided Mu'nis al-Khadim in his campaign against the Saffarid al-Layth ibn Ali in Sijistan and Fars, and later against the former Saffarid general and rebel Subkara and his lieutenant al-Qattal. The Abbasid forces under Mu'nis al-Khadim succeeded in suppressing the rebellion by 910/1, with al-Qattal being captured by Husayn in person, according to a celebratory poem by the later Hamdanid poet Abu Firas.

Abu Firas further reports that Husayn was offered the governorship of Fars, but refused, and returned to Baghdad. Ibn al-Furat, who probably still mistrusted his intentions, promptly dispatched him to the governorship of the Diyar Rabi'a, the province encompassing the eastern Jazira, including Mosul. From this post, Husayn led a raiding campaign against the Byzantine Empire in 913/4. Soon after, however, an open rift developed between Husayn and the vizier Ali ibn Isa al-Jarrah. The reason is unclear, but revolved around the finances of Husayn's province. In 914/5 he rose in open rebellion, assembling a force of 30,000 Arabs and Kurds in the Jazira, a testament to his influence there. He managed to defeat a caliphal army sent against him, but when confronted by the redoubtable Mu'nis al-Khadim, recalled from Egypt, he was defeated and captured in February 916 while trying to flee north into Armenia. He was brought to Baghdad, where he was publicly paraded across the city in ritual humiliation, riding a camel and wearing a cap of shame. He was put into prison, and executed in October/November 918 on the caliph's orders.

The reason for Husayn's execution is unclear. The historian of the Hamdanid dynasty, Marius Canard, suggested that it may have been due to his involvement in a Shi'a-inspired conspiracy, possibly connected to the dismissal of Ibn al-Furat from his second vizierate during the same period, or with the rebellion of the autonomous governor of Adharbayjan, Yusuf ibn Abi'l-Saj, whom al-Muqtadir may have suspected of ties with the imprisoned Husayn. As Canard writes, "in any case the caliph must have feared that if Husayn were released he would once again start a revolt, either through a desire for independence or as a Shi'i. In order to avoid attempts by those (probably numerous) who desired his release to secure it by force, the caliph preferred to take a measure which put a stop to all intrigue".

Despite Husayn's rebellion and execution, the Hamdanid family continued to prosper: his brothers were soon released from captivity, and Abdallah rose to prominence by aligning himself with Mu'nis al-Khadim and sharing in the ups and downs of the court politics in Baghdad. It was Abdallah's two sons, however, al-Hasan and Ali, better known by their honorific titles Nasir al-Dawla and Sayf al-Dawla, who established the family as the ruling dynasty in the semi-independent emirates of Mosul (until 978) and Aleppo (until 1002) respectively.

Character and assessment
According to Canard, Husayn "stands out more clearly than the supreme commander Mu'nis or any other military leaders" of the period for his ability and valour, as well as for his restive and ambitious spirit. He was also singled out in being of Arab descent, an unusual case among the Caliphate's senior leaders of the period. Canard assesses him as unusually open-minded, and attuned to the ideological turmoil and ferment in the Muslim world of his time, as indicated by his contact with the Sufi mystic al-Hallaj, who dedicated a work on politics to Husayn. Indeed, according to Canard, Husayn's espousal of Shi'ism, and his participation in the abortive coup of 908, can best be seen in light of a desire—typical of Shi'a sympathisers—for a renewal of the Caliphate and the establishment of an "ideal Muslim government", something which the corrupt and decadent Abbasids were no longer capable of. Finally, although it fell to his brother to found the actual Hamdanid dynasty, it was Husayn who first gave his family a taste of power and glory, for which he was later celebrated in the poetry of Abu Firas.

References

Bibliography

9th-century births
918 deaths
9th-century people from the Abbasid Caliphate
10th-century people from the Abbasid Caliphate
10th-century executions by the Abbasid Caliphate
Abbasid governors of Jibal
Abbasid governors of Mosul
Abbasid people of the Arab–Byzantine wars
Executed military personnel
Generals of the Abbasid Caliphate
Husayn
Iraqi Shia Muslims
Rebels from the Abbasid Caliphate
9th-century Arab people
10th-century Arab people

Husayn ibn Hamdan


Templet is a mountain north of Sassenfjorden, at the south side of Bünsow Land at Spitsbergen, Svalbard. Its height is 766 metre. The name Templet stems from its resemblance to a ruined Gothic cathedral, consisting of eroded horizontal layers of shales, silicates and limestones.

The mountain lies within the Sassen – Bünsow Land National Park, and is regarded as a tourist attraction.

References

Mountains of Spitsbergen

Templet (Svalbard)


Suede (pronounced  ) is a kind of leather with a soft and fuzzy finish. It is often used for making jackets, shoes, fabrics, bags, furniture, and more. The word "suede" originally comes from French and means "gloves from Sweden."

Suede leather is crafted from the underside of animal skin, which is smoother and more flexible than the top layer. However, it's not as tough or long-lasting. This material is great for making things feel soft and comfortable.

Production
Suede leather is created from the softer underside of animal skin. It's mainly made from lamb skin, although goat, calf, and deerskin are also used. Sometimes, even thick cow and deer hides are turned into suede, but they end up having a more rugged, shaggy texture because of the fibers in them.

In popular culture
Suede, with its unique qualities, has made appearances in various forms of entertainment:
 In the TV show Seinfeld, there's an episode called The Jacket where the character Jerry ruins his expensive suede jacket when he goes out in the snow.
 The famous early rock-n-roll song Blue Suede Shoes was written by Carl Perkins and later covered by Elvis Presley.
 The musician Weird Al Yankovic created a song called King of Suede.
 The term "Suedehead" is used to describe a subculture, and it's also the title of a song by English singer/songwriter Morrissey.

References

Natural materials

Suede


Bruce Alaric Barry (24 October 193420 April 2017 (6 May 2017 is also mentioned as a death date in one source)) was an Australian stage, television and film actor, and singer.

Early life and career
Bruce Barry was born the son of a teacher in Gympie, Queensland, and grew up in Charters Towers. Having started his career as a radio announcer in Queensland and northern New South Wales, Barry ventured into singing at Gold Coast nightclubs and then to acting with the Young Elizabethans, a Sydney-based theatre troupe.  His first role was the title role in Henry V. In his three years there, he performed throughout Australia on various regional tours.

He then combined his singing and acting skills in stage musicals such as Funny Girl (with Jill Perryman), A Little Night Music (with Taina Elg), Irma La Douce, Annie Get Your Gun, Lola Montez, 1776, Hello, Dolly!, and Promises, Promises.  He also acted in straight theatre such as Noël Coward's Private Lives (with Susannah York).

He then became a familiar face on Australian television screens, in such shows as Bellbird, The Spoiler, The Mavis Bramston Show, Skyways, The Flying Doctors, Glenview High, The Restless Years, Possession, and Division 4.

For three years from 1980 he worked in musical theatre in London, in such shows as The Biograph Girl, Marilyn! the Musical [based on the life of Marilyn Monroe, at the Adelphi Theatre; Bruce sang the role of Arthur Miller], H.M.S. Pinafore, and a long-running West End revival of Oklahoma!. He also toured the UK with Evita, appearing with Rula Lenska and others at Leeds and in other UK cities.

While living in London, Bruce Barry presented "An Evening with Bruce Barry", followed by a reception, at the Australian High Commission in Aldwych, London, under the auspices of the Australian Cultural Attache.

Personal life
Bruce Barry was married and divorced twice, and was survived by two children. He died in 2017 in Sydney from complications of dementia.

Filmography

Film
 Ned Kelly (1970) as George King
 Libido (1973) as David
 ABBA: The Movie (1977) as Radio Station Manager
 Patrick (1978) as Dr Brian Wright
 The Umbrella Woman (aka The Good Wife) (1987) as Archie

Television
 Bellbird as Michael Foley
 The Spoiler (1972)  as Jim Carver
 The Mavis Bramston Show
 Skyways as Douglas Stewart
 Division 4
 The Flying Doctors (1987-88)
 Glenview High
 The Restless Years as Miles Dunstan
 Possession (1985) as David Macarthur

References

1934 births
2017 deaths
Australian radio presenters
Australian male stage actors
Australian male musical theatre actors
Australian male soap opera actors
Australian male film actors
20th-century Australian male singers

Bruce Barry (actor)