document_title: Big Bang

question_text: which term refers to an assumed rapid expansion of the universe immediately after the big bang

question_tokens: which term refers to an assumed rapid expansion of the universe immediately after the big bang

text: Big Bang

text: Overview

text: A graphical timeline is available atGraphical timeline of the Big Bang

text: The Belgian astronomer and Catholic priest Georges Lemaître proposed on theoretical grounds that the universe is expanding, which was observationally confirmed soon afterwards by Edwin Hubble.[13][14] In 1927 in the Annales de la Société Scientifique de Bruxelles (Annals of the Scientific Society of Brussels) under the title "Un Univers homogène de masse constante et de rayon croissant rendant compte de la vitesse radiale des nébuleuses extragalactiques" ("A homogeneous Universe of constant mass and growing radius accounting for the radial velocity of extragalactic nebulae"),[15] he presented his new idea that the universe is expanding and provided the first observational estimation of what is known as the Hubble constant.[16].What later will be known as the "Big Bang theory" of the origin of the universe, he called his "hypothesis of the primeval atom" or the "Cosmic Egg".[17]

text: American astronomer Edwin Hubble observed that the distances to faraway galaxies were strongly correlated with their redshifts. This was interpreted to mean that all distant galaxies and clusters are receding away from our vantage point with an apparent velocity proportional to their distance: that is, the farther they are, the faster they move away from us, regardless of direction.[18] Assuming the Copernican principle (that the Earth is not the center of the universe), the only remaining interpretation is that all observable regions of the universe are receding from all others. Since we know that the distance between galaxies increases today, it must mean that in the past galaxies were closer together. The continuous expansion of the universe implies that the universe was denser and hotter in the past.

text: Large particle accelerators can replicate the conditions that prevailed after the early moments of the universe, resulting in confirmation and refinement of the details of the Big Bang model. However, these accelerators can only probe so far into high energy regimes. Consequently, the state of the universe in the earliest instants of the Big Bang expansion is still poorly understood and an area of open investigation and speculation.

text: The first subatomic particles to be formed included protons, neutrons, and electrons. Though simple atomic nuclei formed within the first three minutes after the Big Bang, thousands of years passed before the first electrically neutral atoms formed. The majority of atoms produced by the Big Bang were hydrogen, along with helium and traces of lithium. Giant clouds of these primordial elements later coalesced through gravity to form stars and galaxies, and the heavier elements were synthesized either within stars or during supernovae.

text: The Big Bang theory offers a comprehensive explanation for a broad range of observed phenomena, including the abundance of light elements, the CMB, large scale structure, and Hubble's Law.[7] The framework for the Big Bang model relies on Albert Einstein's theory of general relativity and on simplifying assumptions such as homogeneity and isotropy of space. The governing equations were formulated by Alexander Friedmann, and similar solutions were worked on by Willem de Sitter. Since then, astrophysicists have incorporated observational and theoretical additions into the Big Bang model, and its parametrization as the Lambda-CDM model serves as the framework for current investigations of theoretical cosmology. The Lambda-CDM model is the current "standard model" of Big Bang cosmology, consensus is that it is the simplest model that can account for the various measurements and observations relevant to cosmology.

text: Timeline

text: Singularity

text: Extrapolation of the expansion of the universe backwards in time using general relativity yields an infinite density and temperature at a finite time in the past.[19] This singularity indicates that general relativity is not an adequate description of the laws of physics in this regime. Models based on general relativity alone can not extrapolate toward the singularity beyond the end of the Planck epoch.

text: This primordial singularity is itself sometimes called "the Big Bang",[20] but the term can also refer to a more generic early hot, dense phase[21][notes 1] of the universe. In either case, "the Big Bang" as an event is also colloquially referred to as the "birth" of our universe since it represents the point in history where the universe can be verified to have entered into a regime where the laws of physics as we understand them (specifically general relativity and the standard model of particle physics) work. Based on measurements of the expansion using Type Ia supernovae and measurements of temperature fluctuations in the cosmic microwave background, the time that has passed since that event — otherwise known as the "age of the universe" — is 13.799 ± 0.021 billion years.[22] The agreement of independent measurements of this age supports the ΛCDM model that describes in detail the characteristics of the universe.

text: Despite being extremely dense at this time—far denser than is usually required to form a black hole—the universe did not re-collapse into a black hole. This may be explained by considering that commonly-used calculations and limits for gravitational collapse are usually based upon objects of relatively constant size, such as stars, and do not apply to rapidly expanding space such as the Big Bang.

text: Inflation and baryogenesis

text: The earliest phases of the Big Bang are subject to much speculation. In the most common models the universe was filled homogeneously and isotropically with a very high energy density and huge temperatures and pressures and was very rapidly expanding and cooling. Approximately 10−37 seconds into the expansion, a phase transition caused a cosmic inflation, during which the universe grew exponentially during which time density fluctuations that occurred because of the uncertainty principle were amplified into the seeds that would later form the large-scale structure of the universe.[23] After inflation stopped, reheating occurred until the universe obtained the temperatures required for the production of a quark–gluon plasma as well as all other elementary particles.[24] Temperatures were so high that the random motions of particles were at relativistic speeds, and particle–antiparticle pairs of all kinds were being continuously created and destroyed in collisions.[5] At some point, an unknown reaction called baryogenesis violated the conservation of baryon number, leading to a very small excess of quarks and leptons over antiquarks and antileptons—of the order of one part in 30 million. This resulted in the predominance of matter over antimatter in the present universe.[25]

text: Cooling

text: The universe continued to decrease in density and fall in temperature, hence the typical energy of each particle was decreasing. Symmetry breaking phase transitions put the fundamental forces of physics and the parameters of elementary particles into their present form.[26] After about 10−11 seconds, the picture becomes less speculative, since particle energies drop to values that can be attained in particle accelerators. At about 10−6 seconds, quarks and gluons combined to form baryons such as protons and neutrons. The small excess of quarks over antiquarks led to a small excess of baryons over antibaryons. The temperature was now no longer high enough to create new proton–antiproton pairs (similarly for neutrons–antineutrons), so a mass annihilation immediately followed, leaving just one in 1010 of the original protons and neutrons, and none of their antiparticles. A similar process happened at about 1 second for electrons and positrons. After these annihilations, the remaining protons, neutrons and electrons were no longer moving relativistically and the energy density of the universe was dominated by photons (with a minor contribution from neutrinos).

text: A few minutes into the expansion, when the temperature was about a billion (one thousand million) kelvin and the density was about that of air, neutrons combined with protons to form the universe's deuterium and helium nuclei in a process called Big Bang nucleosynthesis.[27] Most protons remained uncombined as hydrogen nuclei.[28]

text: As the universe cooled, the rest mass energy density of matter came to gravitationally dominate that of the photon radiation. After about 379,000 years, the electrons and nuclei combined into atoms (mostly hydrogen); hence the radiation decoupled from matter and continued through space largely unimpeded. This relic radiation is known as the cosmic microwave background radiation.[28] The chemistry of life may have begun shortly after the Big Bang, 13.8 billion years ago, during a habitable epoch when the universe was only 10–17 million years old.[29][30][31]

text: Structure formation

text:
Over a long period of time, the slightly denser regions of the nearly uniformly distributed matter gravitationally attracted nearby matter and thus grew even denser, forming gas clouds, stars, galaxies, and the other astronomical structures observable today.[5] The details of this process depend on the amount and type of matter in the universe. The four possible types of matter are known as cold dark matter, warm dark matter, hot dark matter, and baryonic matter. The best measurements available, from Wilkinson Microwave Anisotropy Probe (WMAP), show that the data is well-fit by a Lambda-CDM model in which dark matter is assumed to be cold (warm dark matter is ruled out by early reionization),[33] and is estimated to make up about 23% of the matter/energy of the universe, while baryonic matter makes up about 4.6%.[34] In an "extended model" which includes hot dark matter in the form of neutrinos, then if the "physical baryon density"

Ω

b

h

2

{\displaystyle \Omega _{\text{b}}h^{2}}

 is estimated at about 0.023 (this is different from the 'baryon density'

Ω

b

{\displaystyle \Omega _{\text{b}}}

 expressed as a fraction of the total matter/energy density, which as noted above is about 0.046), and the corresponding cold dark matter density Ωch2 is about 0.11, the corresponding neutrino density Ωvh2 is estimated to be less than 0.0062.[34]

text: Cosmic acceleration

text: Independent lines of evidence from Type Ia supernovae and the CMB imply that the universe today is dominated by a mysterious form of energy known as dark energy, which apparently permeates all of space. The observations suggest 73% of the total energy density of today's universe is in this form. When the universe was very young, it was likely infused with dark energy, but with less space and everything closer together, gravity predominated, and it was slowly braking the expansion. But eventually, after numerous billion years of expansion, the growing abundance of dark energy caused the expansion of the universe to slowly begin to accelerate.[11]

text: Dark energy in its simplest formulation takes the form of the cosmological constant term in Einstein's field equations of general relativity, but its composition and mechanism are unknown and, more generally, the details of its equation of state and relationship with the Standard Model of particle physics continue to be investigated both through observation and theoretically.[11]

text: All of this cosmic evolution after the inflationary epoch can be rigorously described and modeled by the ΛCDM model of cosmology, which uses the independent frameworks of quantum mechanics and Einstein's General Relativity. There is no well-supported model describing the action prior to 10−15 seconds or so. Apparently a new unified theory of quantum gravitation is needed to break this barrier. Understanding this earliest of eras in the history of the universe is currently one of the greatest unsolved problems in physics.

text: Features of the model

text: The Big Bang theory depends on two major assumptions: the universality of physical laws and the cosmological principle. The cosmological principle states that on large scales the universe is homogeneous and isotropic.

text: These ideas were initially taken as postulates, but today there are efforts to test each of them. For example, the first assumption has been tested by observations showing that largest possible deviation of the fine structure constant over much of the age of the universe is of order 10−5.[35] Also, general relativity has passed stringent tests on the scale of the Solar System and binary stars.[notes 2]

text: If the large-scale universe appears isotropic as viewed from Earth, the cosmological principle can be derived from the simpler Copernican principle, which states that there is no preferred (or special) observer or vantage point. To this end, the cosmological principle has been confirmed to a level of 10−5 via observations of the CMB. The universe has been measured to be homogeneous on the largest scales at the 10% level.[36]

text: Expansion of space

text:
General relativity describes spacetime by a metric, which determines the distances that separate nearby points. The points, which can be galaxies, stars, or other objects, are themselves specified using a coordinate chart or "grid" that is laid down over all spacetime. The cosmological principle implies that the metric should be homogeneous and isotropic on large scales, which uniquely singles out the Friedmann–Lemaître–Robertson–Walker metric (FLRW metric).
This metric contains a scale factor, which describes how the size of the universe changes with time. This enables a convenient choice of a coordinate system to be made, called comoving coordinates. In this coordinate system, the grid expands along with the universe, and objects that are moving only because of the expansion of the universe, remain at fixed points on the grid. While their coordinate distance (comoving distance) remains constant, the physical distance between two such co-moving points expands proportionally with the scale factor of the universe.[37]

text: The Big Bang is not an explosion of matter moving outward to fill an empty universe. Instead, space itself expands with time everywhere and increases the physical distance between two comoving points. In other words, the Big Bang is not an explosion in space, but rather an expansion of space.[5] Because the FLRW metric assumes a uniform distribution of mass and energy, it applies to our universe only on large scales—local concentrations of matter such as our galaxy are gravitationally bound and as such do not experience the large-scale expansion of space.[38]

text: Horizons

text: An important feature of the Big Bang spacetime is the presence of particle horizons. Since the universe has a finite age, and light travels at a finite speed, there may be events in the past whose light has not had time to reach us. This places a limit or a past horizon on the most distant objects that can be observed. Conversely, because space is expanding, and more distant objects are receding ever more quickly, light emitted by us today may never "catch up" to very distant objects. This defines a future horizon, which limits the events in the future that we will be able to influence. The presence of either type of horizon depends on the details of the FLRW model that describes our universe.[39]

text: Our understanding of the universe back to very early times suggests that there is a past horizon, though in practice our view is also limited by the opacity of the universe at early times. So our view cannot extend further backward in time, though the horizon recedes in space. If the expansion of the universe continues to accelerate, there is a future horizon as well.[39]

text: History

text: Etymology

text: English astronomer Fred Hoyle is credited with coining the term "Big Bang" during a 1949 BBC radio broadcast, saying: "These theories were based on the hypothesis that all the matter in the universe was created in one big bang at a particular time in the remote past."[40]

text: It is popularly reported that Hoyle, who favored an alternative "steady state" cosmological model, intended this to be pejorative,[41] but Hoyle explicitly denied this and said it was just a striking image meant to highlight the difference between the two models.[42][43][44]:129

text: Development

text: The Big Bang theory developed from observations of the structure of the universe and from theoretical considerations. In 1912 Vesto Slipher measured the first Doppler shift of a "spiral nebula" (spiral nebula is the obsolete term for spiral galaxies), and soon discovered that almost all such nebulae were receding from Earth. He did not grasp the cosmological implications of this fact, and indeed at the time it was highly controversial whether or not these nebulae were "island universes" outside our Milky Way.[46][47] Ten years later, Alexander Friedmann, a Russian cosmologist and mathematician, derived the Friedmann equations from Albert Einstein's equations of general relativity, showing that the universe might be expanding in contrast to the static universe model advocated by Einstein at that time.[48] In 1924 Edwin Hubble's measurement of the great distance to the nearest spiral nebulae showed that these systems were indeed other galaxies. Independently deriving Friedmann's equations in 1927, Georges Lemaître, a Belgian physicist, proposed that the inferred recession of the nebulae was due to the expansion of the universe.[49]

text: In 1931 Lemaître went further and suggested that the evident expansion of the universe, if projected back in time, meant that the further in the past the smaller the universe was, until at some finite time in the past all the mass of the universe was concentrated into a single point, a "primeval atom" where and when the fabric of time and space came into existence.[50]

text: Starting in 1924, Hubble painstakingly developed a series of distance indicators, the forerunner of the cosmic distance ladder, using the 100-inch (2.5 m) Hooker telescope at Mount Wilson Observatory. This allowed him to estimate distances to galaxies whose redshifts had already been measured, mostly by Slipher. In 1929 Hubble discovered a correlation between distance and recession velocity—now known as Hubble's law.[18][51] Lemaître had already shown that this was expected, given the cosmological principle.[11]

text: In the 1920s and 1930s almost every major cosmologist preferred an eternal steady state universe, and several complained that the beginning of time implied by the Big Bang imported religious concepts into physics; this objection was later repeated by supporters of the steady state theory.[52] This perception was enhanced by the fact that the originator of the Big Bang theory, Georges Lemaître, was a Roman Catholic priest.[53] Arthur Eddington agreed with Aristotle that the universe did not have a beginning in time, viz., that matter is eternal. A beginning in time was "repugnant" to him.[54][55] Lemaître, however, thought that

text: If the world has begun with a single quantum, the notions of space and time would altogether fail to have any meaning at the beginning; they would only begin to have a sensible meaning when the original quantum had been divided into a sufficient number of quanta. If this suggestion is correct, the beginning of the world happened a little before the beginning of space and time.[56]

text: During the 1930s other ideas were proposed as non-standard cosmologies to explain Hubble's observations, including the Milne model,[57] the oscillatory universe (originally suggested by Friedmann, but advocated by Albert Einstein and Richard Tolman)[58] and Fritz Zwicky's tired light hypothesis.[59]

text: After World War II, two distinct possibilities emerged. One was Fred Hoyle's steady state model, whereby new matter would be created as the universe seemed to expand. In this model the universe is roughly the same at any point in time.[60] The other was Lemaître's Big Bang theory, advocated and developed by George Gamow, who introduced big bang nucleosynthesis (BBN)[61] and whose associates, Ralph Alpher and Robert Herman, predicted the CMB.[62] Ironically, it was Hoyle who coined the phrase that came to be applied to Lemaître's theory, referring to it as "this big bang idea" during a BBC Radio broadcast in March 1949.[44][notes 3] For a while, support was split between these two theories. Eventually, the observational evidence, most notably from radio source counts, began to favor Big Bang over Steady State. The discovery and confirmation of the CMB in 1964 secured the Big Bang as the best theory of the origin and evolution of the universe.[64] Much of the current work in cosmology includes understanding how galaxies form in the context of the Big Bang, understanding the physics of the universe at earlier and earlier times, and reconciling observations with the basic theory.

text: In 1968 and 1970 Roger Penrose, Stephen Hawking, and George F. R. Ellis published papers where they showed that mathematical singularities were an inevitable initial condition of general relativistic models of the Big Bang.[65][66] Then, from the 1970s to the 1990s, cosmologists worked on characterizing the features of the Big Bang universe and resolving outstanding problems. In 1981, Alan Guth made a breakthrough in theoretical work on resolving certain outstanding theoretical problems in the Big Bang theory with the introduction of an epoch of rapid expansion in the early universe he called "inflation".[67] Meanwhile, during these decades, two questions in observational cosmology that generated much discussion and disagreement were over the precise values of the Hubble Constant[68] and the matter-density of the universe (before the discovery of dark energy, thought to be the key predictor for the eventual fate of the universe).[69]

text: In the mid-1990s, observations of certain globular clusters appeared to indicate that they were about 15 billion years old, which conflicted with most then-current estimates of the age of the universe (and indeed with the age measured today). This issue was later resolved when new computer simulations, which included the effects of mass loss due to stellar winds, indicated a much younger age for globular clusters.[70] While there still remain some questions as to how accurately the ages of the clusters are measured, globular clusters are of interest to cosmology as some of the oldest objects in the universe.

text: Significant progress in Big Bang cosmology has been made since the late 1990s as a result of advances in telescope technology as well as the analysis of data from satellites such as COBE,[71] the Hubble Space Telescope and WMAP.[72] Cosmologists now have fairly precise and accurate measurements of many of the parameters of the Big Bang model, and have made the unexpected discovery that the expansion of the universe appears to be accelerating.

text: Observational evidence

text:
"[The] big bang picture is too firmly grounded in data from every area to be proved invalid in its general features."
Lawrence Krauss[73]

tag: div

text: The earliest and most direct observational evidence of the validity of the theory are the expansion of the universe according to Hubble's law (as indicated by the redshifts of galaxies), discovery and measurement of the cosmic microwave background and the relative abundances of light elements produced by Big Bang nucleosynthesis. More recent evidence includes observations of galaxy formation and evolution, and the distribution of large-scale cosmic structures,[74] These are sometimes called the "four pillars" of the Big Bang theory.[75]

text: Precise modern models of the Big Bang appeal to various exotic physical phenomena that have not been observed in terrestrial laboratory experiments or incorporated into the Standard Model of particle physics. Of these features, dark matter is currently subjected to the most active laboratory investigations.[76] Remaining issues include the cuspy halo problem and the dwarf galaxy problem of cold dark matter. Dark energy is also an area of intense interest for scientists, but it is not clear whether direct detection of dark energy will be possible.[77] Inflation and baryogenesis remain more speculative features of current Big Bang models. Viable, quantitative explanations for such phenomena are still being sought. These are currently unsolved problems in physics.

text: Hubble's law and the expansion of space

text:
Observations of distant galaxies and quasars show that these objects are redshifted—the light emitted from them has been shifted to longer wavelengths. This can be seen by taking a frequency spectrum of an object and matching the spectroscopic pattern of emission lines or absorption lines corresponding to atoms of the chemical elements interacting with the light. These redshifts are uniformly isotropic, distributed evenly among the observed objects in all directions. If the redshift is interpreted as a Doppler shift, the recessional velocity of the object can be calculated. For some galaxies, it is possible to estimate distances via the cosmic distance ladder. When the recessional velocities are plotted against these distances, a linear relationship known as Hubble's law is observed:[18]

v
=

H

0

D

{\displaystyle v=H_{0}D}

where

text:
v

{\displaystyle v}

 is the recessional velocity of the galaxy or other distant object,

D

{\displaystyle D}

 is the comoving distance to the object, and

H

0

{\displaystyle H_{0}}

 is Hubble's constant, measured to be 7001704000000000000♠70.4+1.3−1.4 km/s/Mpc by the WMAP probe.[34]

text: Hubble's law has two possible explanations. Either we are at the center of an explosion of galaxies—which is untenable given the Copernican principle—or the universe is uniformly expanding everywhere. This universal expansion was predicted from general relativity by Alexander Friedmann in 1922[48] and Georges Lemaître in 1927,[49] well before Hubble made his 1929 analysis and observations, and it remains the cornerstone of the Big Bang theory as developed by Friedmann, Lemaître, Robertson, and Walker.

text: The theory requires the relation v = HD to hold at all times, where D is the comoving distance, v is the recessional velocity, and v, H, and D vary as the universe expands (hence we write H0 to denote the present-day Hubble "constant"). For distances much smaller than the size of the observable universe, the Hubble redshift can be thought of as the Doppler shift corresponding to the recession velocity v. However, the redshift is not a true Doppler shift, but rather the result of the expansion of the universe between the time the light was emitted and the time that it was detected.[78]

text: That space is undergoing metric expansion is shown by direct observational evidence of the Cosmological principle and the Copernican principle, which together with Hubble's law have no other explanation. Astronomical redshifts are extremely isotropic and homogeneous,[18] supporting the Cosmological principle that the universe looks the same in all directions, along with much other evidence. If the redshifts were the result of an explosion from a center distant from us, they would not be so similar in different directions.

text: Measurements of the effects of the cosmic microwave background radiation on the dynamics of distant astrophysical systems in 2000 proved the Copernican principle, that, on a cosmological scale, the Earth is not in a central position.[79] Radiation from the Big Bang was demonstrably warmer at earlier times throughout the universe. Uniform cooling of the CMB over billions of years is explainable only if the universe is experiencing a metric expansion, and excludes the possibility that we are near the unique center of an explosion.

text: Cosmic microwave background radiation

text: In 1964 Arno Penzias and Robert Wilson serendipitously discovered the cosmic background radiation, an omnidirectional signal in the microwave band.[64] Their discovery provided substantial confirmation of the big-bang predictions by Alpher, Herman and Gamow around 1950. Through the 1970s the radiation was found to be approximately consistent with a black body spectrum in all directions; this spectrum has been redshifted by the expansion of the universe, and today corresponds to approximately 2.725 K. This tipped the balance of evidence in favor of the Big Bang model, and Penzias and Wilson were awarded a Nobel Prize in 1978.

text: The surface of last scattering corresponding to emission of the CMB occurs shortly after recombination, the epoch when neutral hydrogen becomes stable. Prior to this, the universe comprised a hot dense photon-baryon plasma sea where photons were quickly scattered from free charged particles. Peaking at around 7013117394272000000♠372±14 kyr,[33] the mean free path for a photon becomes long enough to reach the present day and the universe becomes transparent.

text: In 1989, NASA launched the Cosmic Background Explorer satellite (COBE), which made two major advances: in 1990, high-precision spectrum measurements showed that the CMB frequency spectrum is an almost perfect blackbody with no deviations at a level of 1 part in 104, and measured a residual temperature of 2.726 K (more recent measurements have revised this figure down slightly to 2.7255 K); then in 1992, further COBE measurements discovered tiny fluctuations (anisotropies) in the CMB temperature across the sky, at a level of about one part in 105.[71] John C. Mather and George Smoot were awarded the 2006 Nobel Prize in Physics for their leadership in these results.

text: During the following decade, CMB anisotropies were further investigated by a large number of ground-based and balloon experiments. In 2000–2001 several experiments, most notably BOOMERanG, found the shape of the universe to be spatially almost flat by measuring the typical angular size (the size on the sky) of the anisotropies.[84][85][86]

text: In early 2003, the first results of the Wilkinson Microwave Anisotropy Probe (WMAP) were released, yielding what were at the time the most accurate values for some of the cosmological parameters. The results disproved several specific cosmic inflation models, but are consistent with the inflation theory in general.[72] The Planck space probe was launched in May 2009. Other ground and balloon based cosmic microwave background experiments are ongoing.

text: Abundance of primordial elements

text: Using the Big Bang model it is possible to calculate the concentration of helium-4, helium-3, deuterium, and lithium-7 in the universe as ratios to the amount of ordinary hydrogen.[27] The relative abundances depend on a single parameter, the ratio of photons to baryons. This value can be calculated independently from the detailed structure of CMB fluctuations. The ratios predicted (by mass, not by number) are about 0.25 for 4He/H, about 10−3 for 2H/H, about 10−4 for 3He/H and about 10−9 for 7Li/H.[27]

text: The measured abundances all agree at least roughly with those predicted from a single value of the baryon-to-photon ratio. The agreement is excellent for deuterium, close but formally discrepant for 4He, and off by a factor of two for 7Li; in the latter two cases there are substantial systematic uncertainties. Nonetheless, the general consistency with abundances predicted by Big Bang nucleosynthesis is strong evidence for the Big Bang, as the theory is the only known explanation for the relative abundances of light elements, and it is virtually impossible to "tune" the Big Bang to produce much more or less than 20–30% helium.[87] Indeed, there is no obvious reason outside of the Big Bang that, for example, the young universe (i.e., before star formation, as determined by studying matter supposedly free of stellar nucleosynthesis products) should have more helium than deuterium or more deuterium than 3He, and in constant ratios, too.[88]:182–185

text: Galactic evolution and distribution

text: Detailed observations of the morphology and distribution of galaxies and quasars are in agreement with the current state of the Big Bang theory. A combination of observations and theory suggest that the first quasars and galaxies formed about a billion years after the Big Bang, and since then, larger structures have been forming, such as galaxy clusters and superclusters.[89]

text: Populations of stars have been aging and evolving, so that distant galaxies (which are observed as they were in the early universe) appear very different from nearby galaxies (observed in a more recent state). Moreover, galaxies that formed relatively recently, appear markedly different from galaxies formed at similar distances but shortly after the Big Bang. These observations are strong arguments against the steady-state model. Observations of star formation, galaxy and quasar distributions and larger structures, agree well with Big Bang simulations of the formation of structure in the universe, and are helping to complete details of the theory.[89][90]

text: Primordial gas clouds

text: In 2011, astronomers found what they believe to be pristine clouds of primordial gas by analyzing absorption lines in the spectra of distant quasars. Before this discovery, all other astronomical objects have been observed to contain heavy elements that are formed in stars. These two clouds of gas contain no elements heavier than hydrogen and deuterium.[95][96] Since the clouds of gas have no heavy elements, they likely formed in the first few minutes after the Big Bang, during Big Bang nucleosynthesis.

text: Other lines of evidence

text: The age of the universe as estimated from the Hubble expansion and the CMB is now in good agreement with other estimates using the ages of the oldest stars, both as measured by applying the theory of stellar evolution to globular clusters and through radiometric dating of individual Population II stars.[97]

text: The prediction that the CMB temperature was higher in the past has been experimentally supported by observations of very low temperature absorption lines in gas clouds at high redshift.[98] This prediction also implies that the amplitude of the Sunyaev–Zel'dovich effect in clusters of galaxies does not depend directly on redshift. Observations have found this to be roughly true, but this effect depends on cluster properties that do change with cosmic time, making precise measurements difficult.[99][100]

text: Future observations

text: Future gravitational waves observatories might be able to detect primordial gravitational waves, relics of the early universe, up to less than a second after the Big Bang.[101][102]

text: Problems and related issues in physics

text: As with any theory, a number of mysteries and problems have arisen as a result of the development of the Big Bang theory. Some of these mysteries and problems have been resolved while others are still outstanding. Proposed solutions to some of the problems in the Big Bang model have revealed new mysteries of their own. For example, the horizon problem, the magnetic monopole problem, and the flatness problem are most commonly resolved with inflationary theory, but the details of the inflationary universe are still left unresolved and many, including some founders of the theory, say it has been disproven.[103][104][105][106] What follows are a list of the mysterious aspects of the Big Bang theory still under intense investigation by cosmologists and astrophysicists.

text: Baryon asymmetry

text: It is not yet understood why the universe has more matter than antimatter.[107] It is generally assumed that when the universe was young and very hot it was in statistical equilibrium and contained equal numbers of baryons and antibaryons. However, observations suggest that the universe, including its most distant parts, is made almost entirely of matter. A process called baryogenesis was hypothesized to account for the asymmetry. For baryogenesis to occur, the Sakharov conditions must be satisfied. These require that baryon number is not conserved, that C-symmetry and CP-symmetry are violated and that the universe depart from thermodynamic equilibrium.[108] All these conditions occur in the Standard Model, but the effects are not strong enough to explain the present baryon asymmetry.

text: Dark energy

text: Measurements of the redshift–magnitude relation for type Ia supernovae indicate that the expansion of the universe has been accelerating since the universe was about half its present age. To explain this acceleration, general relativity requires that much of the energy in the universe consists of a component with large negative pressure, dubbed "dark energy".[11]

text: Dark energy, though speculative, solves numerous problems. Measurements of the cosmic microwave background indicate that the universe is very nearly spatially flat, and therefore according to general relativity the universe must have almost exactly the critical density of mass/energy. But the mass density of the universe can be measured from its gravitational clustering, and is found to have only about 30% of the critical density.[11] Since theory suggests that dark energy does not cluster in the usual way it is the best explanation for the "missing" energy density. Dark energy also helps to explain two geometrical measures of the overall curvature of the universe, one using the frequency of gravitational lenses, and the other using the characteristic pattern of the large-scale structure as a cosmic ruler.

text: Negative pressure is believed to be a property of vacuum energy, but the exact nature and existence of dark energy remains one of the great mysteries of the Big Bang. Results from the WMAP team in 2008 are in accordance with a universe that consists of 73% dark energy, 23% dark matter, 4.6% regular matter and less than 1% neutrinos.[34] According to theory, the energy density in matter decreases with the expansion of the universe, but the dark energy density remains constant (or nearly so) as the universe expands. Therefore, matter made up a larger fraction of the total energy of the universe in the past than it does today, but its fractional contribution will fall in the far future as dark energy becomes even more dominant.

text: The dark energy component of the universe has been explained by theorists using a variety of competing theories including Einstein's cosmological constant but also extending to more exotic forms of quintessence or other modified gravity schemes.[109] A cosmological constant problem, sometimes called the "most embarrassing problem in physics", results from the apparent discrepancy between the measured energy density of dark energy, and the one naively predicted from Planck units.[110]

text: Dark matter

text: During the 1970s and the 1980s, various observations showed that there is not sufficient visible matter in the universe to account for the apparent strength of gravitational forces within and between galaxies. This led to the idea that up to 90% of the matter in the universe is dark matter that does not emit light or interact with normal baryonic matter. In addition, the assumption that the universe is mostly normal matter led to predictions that were strongly inconsistent with observations. In particular, the universe today is far more lumpy and contains far less deuterium than can be accounted for without dark matter. While dark matter has always been controversial, it is inferred by various observations: the anisotropies in the CMB, galaxy cluster velocity dispersions, large-scale structure distributions, gravitational lensing studies, and X-ray measurements of galaxy clusters.[111]

text: Indirect evidence for dark matter comes from its gravitational influence on other matter, as no dark matter particles have been observed in laboratories. Many particle physics candidates for dark matter have been proposed, and several projects to detect them directly are underway.[112]

text: Additionally, there are outstanding problems associated with the currently favored cold dark matter model which include the dwarf galaxy problem[113] and the cuspy halo problem.[114] Alternative theories have been proposed that do not require a large amount of undetected matter, but instead modify the laws of gravity established by Newton and Einstein; yet no alternative theory has been as successful as the cold dark matter proposal in explaining all extant observations.[115]

text: Horizon problem

text: The horizon problem results from the premise that information cannot travel faster than light. In a universe of finite age this sets a limit—the particle horizon—on the separation of any two regions of space that are in causal contact.[116] The observed isotropy of the CMB is problematic in this regard: if the universe had been dominated by radiation or matter at all times up to the epoch of last scattering, the particle horizon at that time would correspond to about 2 degrees on the sky. There would then be no mechanism to cause wider regions to have the same temperature.[88]:191–202

text: A resolution to this apparent inconsistency is offered by inflationary theory in which a homogeneous and isotropic scalar energy field dominates the universe at some very early period (before baryogenesis). During inflation, the universe undergoes exponential expansion, and the particle horizon expands much more rapidly than previously assumed, so that regions presently on opposite sides of the observable universe are well inside each other's particle horizon. The observed isotropy of the CMB then follows from the fact that this larger region was in causal contact before the beginning of inflation.[23]:180–186

text: Heisenberg's uncertainty principle predicts that during the inflationary phase there would be quantum thermal fluctuations, which would be magnified to cosmic scale. These fluctuations serve as the seeds of all current structure in the universe.[88]:207 Inflation predicts that the primordial fluctuations are nearly scale invariant and Gaussian, which has been accurately confirmed by measurements of the CMB.[117]:sec 6

text: If inflation occurred, exponential expansion would push large regions of space well beyond our observable horizon.[23]:180–186

text: A related issue to the classic horizon problem arises because in most standard cosmological inflation models, inflation ceases well before electroweak symmetry breaking occurs, so inflation should not be able to prevent large-scale discontinuities in the electroweak vacuum since distant parts of the observable universe were causally separate when the electroweak epoch ended.[118]

text: Magnetic monopoles

text: The magnetic monopole objection was raised in the late 1970s. Grand unified theories predicted topological defects in space that would manifest as magnetic monopoles. These objects would be produced efficiently in the hot early universe, resulting in a density much higher than is consistent with observations, given that no monopoles have been found. This problem is also resolved by cosmic inflation, which removes all point defects from the observable universe, in the same way that it drives the geometry to flatness.[116]

text: Flatness problem

text: The flatness problem (also known as the oldness problem) is an observational problem associated with a Friedmann–Lemaître–Robertson–Walker metric (FLRW).[116] The universe may have positive, negative, or zero spatial curvature depending on its total energy density. Curvature is negative, if its density is less than the critical density; positive, if greater; and zero at the critical density, in which case space is said to be flat.

text: The problem is that any small departure from the critical density grows with time, and yet the universe today remains very close to flat.[notes 4] Given that a natural timescale for departure from flatness might be the Planck time, 10−43 seconds,[5] the fact that the universe has reached neither a heat death nor a Big Crunch after billions of years requires an explanation. For instance, even at the relatively late age of a few minutes (the time of nucleosynthesis), the density of the universe must have been within one part in 1014 of its critical value, or it would not exist as it does today.[119]

text: Cause

text: Gottfried Wilhelm Leibniz wrote: "Why is there something rather than nothing? The sufficient reason [...] is found in a substance which [...] is a necessary being bearing the reason for its existence within itself."[120] Philosopher of physics Dean Rickles[121] has argued that numbers and mathematics (or their underlying laws) may necessarily exist.[122][123] Physics may conclude that time did not exist before 'Big Bang', but 'started' with the Big Bang and hence there might be no 'beginning', 'before' or potentially 'cause' and instead always existed.[124][125] Some also argue that nothing cannot exist or that non-existence might never have been an option.[126][127][128][129] Quantum fluctuations, or other laws of physics that may have existed at the start of the Big Bang could then create the conditions for matter to occur.

text: Ultimate fate of the universe

text: Before observations of dark energy, cosmologists considered two scenarios for the future of the universe. If the mass density of the universe were greater than the critical density, then the universe would reach a maximum size and then begin to collapse. It would become denser and hotter again, ending with a state similar to that in which it started—a Big Crunch.[39]

text: Alternatively, if the density in the universe were equal to or below the critical density, the expansion would slow down but never stop. Star formation would cease with the consumption of interstellar gas in each galaxy; stars would burn out, leaving white dwarfs, neutron stars, and black holes. Very gradually, collisions between these would result in mass accumulating into larger and larger black holes. The average temperature of the universe would asymptotically approach absolute zero—a Big Freeze.[130] Moreover, if the proton were unstable, then baryonic matter would disappear, leaving only radiation and black holes. Eventually, black holes would evaporate by emitting Hawking radiation. The entropy of the universe would increase to the point where no organized form of energy could be extracted from it, a scenario known as heat death.[131]:sec VI.D

text: Modern observations of accelerating expansion imply that more and more of the currently visible universe will pass beyond our event horizon and out of contact with us. The eventual result is not known. The ΛCDM model of the universe contains dark energy in the form of a cosmological constant. This theory suggests that only gravitationally bound systems, such as galaxies, will remain together, and they too will be subject to heat death as the universe expands and cools. Other explanations of dark energy, called phantom energy theories, suggest that ultimately galaxy clusters, stars, planets, atoms, nuclei, and matter itself will be torn apart by the ever-increasing expansion in a so-called Big Rip.[132]

text: Misconceptions

text: The following is a partial list of the popular misconceptions about the Big Bang model:

text: The Big Bang as the origin of the universe: One of the common misconceptions about the Big Bang model is the belief that it was the origin of the universe. However, the Big Bang model does not comment about how the universe came into being. Current conception of the Big Bang model assumes the existence of energy, time, and space, and does not comment about their origin or the cause of the dense and high temperature initial state of the universe.[133]

text: The Big Bang was "small": It is misleading to visualize the Big Bang by comparing its size to everyday objects. When the size of the universe at Big Bang is described, it refers to the size of the observable universe, and not the entire universe.[134]

text: Hubble's law violates the special theory of relativity: Hubble's law predicts that galaxies that are beyond Hubble Distance recede faster than the speed of light. However, special relativity does not apply beyond motion through space. Hubble's law describes velocity that results from expansion of space, rather than through space.[134]

text: Doppler redshift vs cosmological red-shift: Astronomers often refer to the cosmological red-shift as a normal Doppler shift,[134] which is a misconception. Although similar, the cosmological red-shift is not identical to the Doppler redshift. The Doppler redshift is based on special relativity, which does not consider the expansion of space. On the contrary, the cosmological red-shift is based on general relativity, in which the expansion of space is considered. Although they may appear identical for nearby galaxies, it may cause confusion if the behavior of distant galaxies is understood through the Doppler redshift.[134]

text: Speculations

text: While the Big Bang model is well established in cosmology, it is likely to be refined. The Big Bang theory, built upon the equations of classical general relativity, indicates a singularity at the origin of cosmic time; this infinite energy density is regarded as impossible in physics.  Still, it is known that the equations are not applicable before the time when the universe cooled down to the Planck temperature, and this conclusion depends on various assumptions, of which some could never be experimentally verified. (Also see Planck epoch.)

text: One proposed refinement to avoid this would-be singularity is to develop a correct treatment of quantum gravity.[135]

text: It is not known what could have preceded the hot dense state of the early universe or how and why it originated, though speculation abounds in the field of cosmogony.

text: Some proposals, each of which entails untested hypotheses, are:

text:
Models including the Hartle–Hawking no-boundary condition, in which the whole of space-time is finite; the Big Bang does represent the limit of time but without any singularity.[136]
Big Bang lattice model, states that the universe at the moment of the Big Bang consists of an infinite lattice of fermions, which is smeared over the fundamental domain so it has rotational, translational and gauge symmetry. The symmetry is the largest symmetry possible and hence the lowest entropy of any state.[137]
Brane cosmology models, in which inflation is due to the movement of branes in string theory; the pre-Big Bang model; the ekpyrotic model, in which the Big Bang is the result of a collision between branes; and the cyclic model, a variant of the ekpyrotic model in which collisions occur periodically. In the latter model the Big Bang was preceded by a Big Crunch and the universe cycles from one process to the other.[138][139][140][141]
Eternal inflation, in which universal inflation ends locally here and there in a random fashion, each end-point leading to a bubble universe, expanding from its own big bang.[142][143]

text: Proposals in the last two categories, see the Big Bang as an event in either a much larger and older universe or in a multiverse.

text: Religious and philosophical interpretations

text: As a description of the origin of the universe, the Big Bang has significant bearing on religion and philosophy.[144][145] As a result, it has become one of the liveliest areas in the discourse between science and religion.[146] Some believe the Big Bang implies a creator,[147][148] and some see its mention in their holy books,[149] while others argue that Big Bang cosmology makes the notion of a creator superfluous.[145][150]


document_title: List of towns in West Virginia

question_text: cities in west virginia that start with s

root

text: List of towns in West Virginia

text: List of towns in West Virginia, arranged in alphabetical order.

tag: p

text:
Top
0–9
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z

tag: ul

text: A[edit]

text:
Addison (Webster Springs)
Albright
Alderson
Anawalt
Anmoore
Ansted
Athens
Auburn

text: B[edit]

text:
Bancroft
Barrackville
Bath (Berkeley Springs)
Bayard
Belington
Belle
Bethany
Beverly
Blacksville
Bolivar
Bradshaw
Bramwell
Brandonville
Bruceton Mills
Buffalo
Burnsville

text: C[edit]

text:
Cairo
Camden-on-Gauley
Capon Bridge
Carpendale
Cedar Grove
Chapmanville
Charlestown
Chesapeake
Clay
Clendenin
Cowen

text: D[edit]

text:
Danville
Davis
Davy
Delbarton
Durbin

text: E[edit]

text:
East Bank
Eleanor
Elizabeth
Elk Garden
Ellenboro

text: F[edit]

text:
Fairview
Falling Spring
Farmington
Fayetteville
Flatwoods
Flemington
Fort Gay
Franklin
Friendly

text: G[edit]

text:
Gassaway
Gauley Bridge
Gilbert
Glasgow
Glenville
Grant Town
Grantsville
Granville

text: H[edit]

text:
Hambleton
Hamlin
Handley
Harman
Harpers Ferry
Harrisville
Hartford City
Hedgesville
Henderson
Hendricks
Hillsboro
Hundred
Huttonsville

text: I[edit]

text: Iaeger

text: J[edit]

text:
Jane Lew
Junior

text: K[edit]

text:
Kermit
Kimball

text: L[edit]

text:
Leon
Lester
Lost Creek
Lumberport

text: M[edit]

text:
Mabscott
Man
Marlinton
Mason
Masontown
Matewan
Matoaka
Meadow Bridge
Middlebourne
Mill Creek
Milton
Mitchell Heights
Monongah
Montrose
Moorefield

text: N[edit]

text:
New Haven
Newburg
North Hills
Northfork
Nutter Fort

text: O[edit]

text:
Oakvale
Oceana

text: P[edit]

text:
Paw Paw
Pax
Peterstown
Piedmont
Pine Grove
Pineville
Poca
Pratt
Pullman

text: Q[edit]

text: Quinwood

text: R[edit]

text:
Rainelle
Reedsville
Reedy
Rhodell
Ridgeley
Rivesville
Rowlesburg
Rupert

text: S[edit]

text:
Sand Fork
Shepherdstown
Smithfield
Sophia
Star City
Sutton
Sylvester

text: T[edit]

text:
Terra Alta
Thurmond
Triadelphia
Tunnelton

text: U[edit]

text: Union

text: W[edit]

text:
Wardensville
Wayne
West Hamlin
West Liberty
West Logan
West Milford
West Union
White Hall
Whitesville
Winfield
Womelsdorf (Coalton)
Worthington

text: Former towns[edit]

text: These communities were once towns but disincorporated.

text:
Dunlow
East Lynn
Jefferson
Littleton


document_title: Second Temple

question_text: who initiated the rebuilding of the second temple

text: Second Temple

text: Biblical narrative[edit]

text: The accession of Cyrus the Great of the Persian Empire in 559 BCE made the re-establishment of the city of Jerusalem and the rebuilding of the Temple possible.[1][2] According to the closing verses of the second book of Chronicles and the books of Ezra and Nehemiah, when the Jewish exiles returned to Jerusalem following a decree from Cyrus the Great (Ezra 1:1–4, 2 Chron 36:22–23), construction started at the original site of Solomon's Temple. After a relatively brief halt due to opposition from peoples who had filled the vacuum during the Jewish captivity (Ezra 4), work resumed c. 521 BCE under Darius the Great (Ezra 5) and was completed during the sixth year of his reign (c. 516 BCE), with the temple dedication taking place the following year.[citation needed]

text: These events represent the final section in the historical narrative of the Hebrew Bible.[1]

text: The original core of the book of Nehemiah, the first-person memoir, may have been combined with the core of the Book of Ezra around 400 BCE. Further editing probably continued into the Hellenistic era.[3]

text: The book tells how Nehemiah, at the court of the king in Susa, is informed that Jerusalem is without walls and resolves to restore them. The king appoints him as governor of the province Yehud Medinata and he travels to Jerusalem. There he rebuilds the walls, despite the opposition of Israel's enemies, and reforms the community in conformity with the law of Moses. After 12 years in Jerusalem, he returns to Susa but subsequently revisits Jerusalem. He finds that the Israelites have been backsliding and taking non-Jewish wives, and he stays in Jerusalem to enforce the Law.

text: Based on the biblical account, after the return from Babylonian captivity, arrangements were immediately made to reorganize the desolated Yehud Province after the demise of the Kingdom of Judah seventy years earlier. The body of pilgrims, forming a band of 42,360,[4] having completed the long and dreary journey of some four months, from the banks of the Euphrates to Jerusalem, were animated in all their proceedings by a strong religious impulse, and therefore one of their first concerns was to restore their ancient house of worship by rebuilding their destroyed Temple[5] and reinstituting the sacrificial rituals known as the korbanot.

text: On the invitation of Zerubbabel, the governor, who showed them a remarkable example of liberality by contributing personally 1,000 golden darics, besides other gifts, the people poured their gifts into the sacred treasury with great enthusiasm.[6] First they erected and dedicated the altar of God on the exact spot where it had formerly stood, and they then cleared away the charred heaps of debris which occupied the site of the old temple; and in the second month of the second year (535 BCE), amid great public excitement and rejoicing, the foundations of the Second Temple were laid. A wide interest was felt in this great movement, although it was regarded with mixed feelings by the spectators (Haggai 2:3, Zechariah 4:10).[5]

text: The Samaritans made proposals for co-operation in the work. Zerubbabel and the elders, however, declined all such cooperation, feeling that the Jews must build the Temple without help. Immediately evil reports were spread regarding the Jews. According to Ezra 4:5, the Samaritans sought to "frustrate their purpose" and sent messengers to Ecbatana and Susa, with the result that the work was suspended.[5]

text: Seven years later, Cyrus the Great, who allowed the Jews to return to their homeland and rebuild the Temple, died (2 Chronicles 36:22–23) and was succeeded by his son Cambyses. On his death, the "false Smerdis", an impostor, occupied the throne for some seven or eight months, and then Darius became king (522 BCE). In the second year of his rule the work of rebuilding the temple was resumed and carried forward to its completion (Ezra 5:6–6:15), under the stimulus of the earnest counsels and admonitions of the prophets Haggai and Zechariah. It was ready for consecration in the spring of 516 BCE, more than twenty years after the return from captivity. The Temple was completed on the third day of the month Adar, in the sixth year of the reign of Darius, amid great rejoicings on the part of all the people (Ezra 6:15,16), although it was evident that the Jews were no longer an independent people, but were subject to a foreign power. The Book of Haggai includes a prediction that the glory of the second temple would be greater than that of the first (Haggai 2:9).[5]

text: Some of the original artifacts from the Temple of Solomon are not mentioned in the sources after its destruction in 597 BCE, and are presumed lost. The Second Temple lacked the following holy articles:

text:
The Ark of the Covenant[2][5] containing the Tablets of Stone, before which were placed[7] the pot of manna and Aaron's rod[5]
The Urim and Thummim[2][5] (divination objects contained in the Hoshen)
The holy oil[5]
The sacred fire.[2][5]

text: In the Second Temple, the Kodesh Hakodashim (Holy of Holies) was separated by curtains rather than a wall as in the First Temple. Still, as in the Tabernacle, the Second Temple included:

text:
The Menorah (golden lamp) for the Hekhal
The Table of Showbread
The golden altar of incense, with golden censers.[5]

text: According to the Mishnah (Middot iii. 6), the "Foundation Stone" stood where the Ark used to be, and the High Priest put his censer on it on Yom Kippur.[2]

text: The Second Temple also included many of the original vessels of gold that had been taken by the Babylonians but restored by Cyrus the Great.[5][8] According to the Babylonian Talmud (Yoma 22b),[2] however, the Temple lacked the Shekinah, the dwelling or settling divine presence of God, and the Ruach HaKodesh, the Spirit of Holiness, present in the first.

text: Rabbinical literature[edit]

text: Traditional rabbinic literature state that the Second Temple stood for 420 years and based on the 2nd-century work Seder Olam Rabbah, placed construction in 350 BCE (3408 AM), 166 years later than secular estimates, and destruction in 70 CE (3829 AM).[9]

text: Rededication by the Maccabees[edit]

text: Following the conquest of Judea by Alexander the Great, it became part of the Ptolemaic Kingdom of Egypt until 200 BCE, when King Antiochus III the Great of Syria defeated King Ptolemy V Epiphanes of Egypt at the Battle of Paneion.[10] Judea became at that moment part of the Seleucid empire of Syria. When the Second Temple in Jerusalem was looted and its religious services stopped, Judaism was effectively outlawed. In 167 BCE, Antiochus IV Epiphanes ordered an altar to Zeus erected in the Temple. He also banned circumcision and ordered pigs to be sacrificed at the altar of the Temple.[11]

text: Following the Maccabean Revolt against the Seleucid empire, the Second Temple was rededicated and became the religious pillar of the Jewish Hasmonean kingdom, as well as culturally associated with the Jewish holiday of Hanukkah.

text: Hasmonean dynasty and Roman conquest[edit]

text: There is some evidence from archaeology that further changes to the structure of the Temple and its surroundings were made during the Hasmonean rule. Salome Alexandra, the queen of Hasmonean Kingdom appointed her elder son Hyrcanus II as the high priest of Judaea. Her younger son Aristobulus II was determined to have the throne, and as soon as she died he seized the throne. Hyrcanus, who was in line to be the king, agreed to be contented with being the high priest. Antipater, the governor of Idumæa, encouraged Hyrcanus not to give up his throne. Eventually Hyrcanus fled to Aretas III, king of the Nabateans, and returned with an army to take back the throne. He defeated Aristobulus and besieged Jerusalem. The Roman general Pompey, who was in Syria fighting against the Armenians in the Third Mithridatic War, sent his lieutenant to investigate the conflict in Judaea. Both Hyrcanus and Aristobulus appealed to him for support. Pompey was not diligent in making a decision about this which caused Aristobulus to march off. He was pursued by Pompey and surrendered but his followers closed Jerusalem to Pompey's forces. The Romans besieged and took the city in 63 BCE. The priests continued with the religious practices inside the Temple during the siege. The temple was not looted or harmed by the Romans. Pompey himself, perhaps inadvertently, went into the Holy of Holies and the next day ordered the priests to repurify the Temple and resume the religious practices.[12]

text: Herod's Temple[edit]

text: Reconstruction of the temple under Herod began with a massive expansion of the Temple Mount. Religious worship and temple rituals continued during the construction process.[13] When the Roman emperor Caligula planned to place his own statue inside the temple, Herod's grandson Agrippa I was able to intervene and convince him against this.

text: Construction[edit]

text: Herod's Temple was one of the larger construction projects of the 1st century BCE.[14] Josephus records that Herod was interested in perpetuating his name through building projects, that his construction programs were extensive and paid for by heavy taxes, but that his masterpiece was the Temple of Jerusalem.[14]

text: The old temple built by Zerubbabel was replaced by a magnificent edifice. An agreement was made between Herod and the Jewish religious authorities: the sacrificial rituals, called offerings, were to be continued unabated for the entire time of construction, and the Temple itself would be constructed by the priests. Later the Exodus 30:13 sanctuary shekel was reinstituted to support the temple as the temple tax.

text: Platform[edit]

text: Mt. Moriah had a plateau at the northern end, and steeply declined on the southern slope. It was Herod's plan that the entire mountain be turned into a giant square platform. The Temple Mount was originally intended to be 1600 feet wide by 900 feet broad by 9 stories high, with walls up to 16 feet thick, but had never been finished. To complete it, a trench was dug around the mountain, and huge stone "bricks" were laid. Some of these weighed well over 100 tons, the largest measuring 44.6 feet by 11 feet by 16.5 feet and weighing approximately 567 to 628 tons,[15][16] while most were in the range of 2.5 by 3.5 by 15 feet (approximately 28 tons). King Herod had architects from Greece, Rome and Egypt plan the construction. The blocks were presumably quarried by using pickaxes to create channels. Then they hammered in wooden beams and flushed them with water to force them out. Once they were removed, they were carved into precise squares and numbered at the quarry to show where they would be installed. The final carving would have been done by using harder stones to grind or chisel them to create precise joints. They would have been transported using oxen and specialized carts. Since the quarry was uphill from the temple they had gravity on their side but care needed to be taken to control the descent. Final installation would have been done using pulleys or cranes. Roman pulleys and cranes weren't strong enough to lift the blocks alone so they may have used multiple cranes and levers to position them.[17] As the mountainside began to rise, the western side was carved away to a vertical wall and bricks were carved to create a virtual continuation of the brick face, which was continued for a while until the northern slope reached ground level. Part of the Antonian hill to the north of Moriah was annexed to the complex and the area between was filled up with landfill.

text: The project began with the building of giant underground vaults upon which the temple would be built so it could be larger than the small flat area on top of Mount Moriah. Ground level at the time was at least 20 ft. (6m) below the current level, as can be seen by walking the Western Wall tunnels. Legend has it that the construction of the entire complex lasted only three years, but other sources such as Josephus say that it took far longer, although the Temple itself may have taken that long. During a Passover visit by Jesus the Jews replied that it had been under construction for 46 years.[18] It is possible that the complex was only a few years completed when the future Emperor Titus destroyed the Temple in 70 CE.

text: Court of the Gentiles[edit]

text: This area was primarily a bazaar, with vendors selling souvenirs, sacrificial animals, food, as well as currency changers, exchanging Roman for Tyrian money because the Jews were not allowed to coin their own money and they viewed Roman currency as an abomination to the Lord,[19] as also mentioned in the New Testament account of Jesus and the Money Changers when Jerusalem was packed with Jews who had come for Passover, perhaps numbering 300,000 to 400,000 pilgrims.[20][21] Guides that provided tours of the premises were also available. Jewish males had the unique opportunity to be shown inside the temple itself.

text: The priests, in their white linen robes and tubular hats, were everywhere, directing pilgrims and advising them on what kinds of sacrifices were to be performed.

text: Behind them, as they entered the Court of the Gentiles from the south through the Huldah Gates, was the Royal Porch, which contained a marketplace, administrative quarters, and a synagogue. On the upper floors, the great Jewish sages held court, priests and Levites performed various chores, and from there, tourists were able to observe the events. The Royal Porch is widely accepted to be part of Herod's work; however, recent archaeological finds in the Western Wall tunnels suggest that it was built in the first century during the reign of Agripas, as opposed to the first century BCE,[22] while the theory that Herod began the extension and the Royal Porch is based mainly on Josephus's possibly politically motivated claim. During Herod's reign the porch was not yet open to the public)

text: To the east of the court was Solomon's Porch, and to the north, the soreg, the "middle wall of separation",[23] a stone wall separating the public area from the inner sanctuary where only Jews could enter, described as being 3 cubits high by Josephus (Wars 5.5.2 [3b] 6.2.4).

text: Pinnacle[edit]

text: The accounts of Jesus' temptations in Matthew's and Luke's gospels both suggest that the Second Temple had one or more pinnacles (Greek: το πτερυγιον του ιερου):

text: Then he [Satan] brought Him to Jerusalem, set Him on the pinnacle of the temple, and said to Him, "If You are the Son of God, throw Yourself down from here."[24]

text: The Greek word used here is pterugion, which literally means a little wing, or by extension anything like a wing such as a battlement or parapet.[25] The archaeologist Benjamin Mazar thought it referred to the southeast corner of the Temple overlooking the Kidron Valley.[26]

text: Inside the Soreg[edit]

text: According to Josephus, there were ten entrances into the inner courts, four on the south, four on the north, one on the east and one leading east to west from the Court of Women to the court of the Israelites, named the Nicanor Gate.[27] The gates were: On the south side (going from west to east) the Fuel Gate, the Firstling Gate, the Water Gate. On the north side, from west to east, are the Jeconiah Gate, the Offering Gate, the Women's Gate and the Song Gate. On the Eastern side, the Nicanor gate, which is where most Jewish visitors entered. A few pieces of the Soreg have survived to the present day.

text: Within this area was the Court of the Women, open to all Jews, male and female. Even a ritually unclean Cohen could enter to perform various housekeeping duties. There was also a place for lepers (considered ritually unclean), as well as a ritual barbershop for Nazirites. In this, the largest of the temple courts, one could see constant dancing, singing and music.

text: Only men were allowed to enter the Court of the Israelites, where they could observe sacrifices of the high priest in the Court of the Priests. The Court of the Priests was reserved for Levite priests.

text: Temple sanctuary[edit]

text: Between the entrance of the building and the curtain veiling the Holy of Holies were the famous vessels of the temple: the menorah, the incense-burning altar, and various other implements.

text: Pilgrimages[edit]

text: Jews from distant parts of the Roman Empire would arrive by boat at the port of Jaffa (now part of Tel Aviv), where they would join a caravan for the three-day trek to the Holy City and would then find lodgings in one of the many hotels or hostelries. Then they changed some of their money from the profane standard Greek and Roman currency for Jewish and Tyrian money, the latter two considered religious.[28][29] The pilgrims would purchase sacrificial animals, usually a pigeon or a lamb, in preparation for the following day's events.

text: The first thing pilgrims would do would be to approach the public entrance on the south side of the Temple Mount complex. They would check their animals, then visit a mikveh, where they would ritually cleanse and purify themselves. The pilgrims would then retrieve their sacrificial animals, and head to the Huldah gates. After ascending a staircase three stories in height, and passing through the gate, the pilgrims would find themselves in the Court of the Gentiles.

text: Destruction[edit]

text: In 66 CE the Jewish population rebelled against the Roman Empire. Four years later, in 70 CE, Roman legions under Titus retook and destroyed much of Jerusalem and the Second Temple. The Arch of Titus, located in Rome and built to commemorate Titus' victory in Judea, depicts a Roman victory procession with soldiers carrying spoils from the Temple, including the Menorah. According to an inscription on the Colosseum, Emperor Vespasian built the Colosseum with war spoils in 79 CE—possibly from the spoils of the Second Temple.[30]

text: The sects of Judaism that had their base in the Temple dwindled in importance, including the priesthood and the Sadducees.[31]

text: The destruction date according to the Hebrew calendar was the 9th of Av, also known as Tisha B'Av.[32] The Temple itself was located on the site of what today is the Dome of the Rock. The gates let out close to Al-Aqsa Mosque (which came much later).[13] Although Jews continued to inhabit the destroyed city, Emperor Hadrian established a new city called Aelia Capitolina. At the end of the Bar Kokhba revolt in 135 CE, many of the Jewish communities were massacred and Jews were banned from living inside Jerusalem. A pagan Roman temple was set up on the former site of Herod's Temple.[12]

text: Archaeology[edit]

text: In 1871, a hewn stone measuring 60 × 90 cm. and engraved with Greek uncials was discovered near a court on the Temple Mount in Jerusalem and identified by Charles Simon Clermont-Ganneau as being the Temple Warning inscription. The stone inscription outlined the prohibition extended unto those who were not of the Jewish nation to proceed beyond the soreg separating the larger Court of the Gentiles and the inner courts. The inscription read in seven lines:

text:
ΜΗΟΕΝΑΑΛΛΟΓΕΝΗΕΙΣΠΟ
ΡΕΥΕΣΟΑΙΕΝΤΟΣΤΟΥΠΕ
ΡΙΤΟΙΕΡΟΝΤΡΥΦΑΚΤΟΥΚΑΙ
ΠΕΡΙΒΟΛΟΥΟΣΔΑΝΛΗ
ΦΘΗΕΑΥΤΩΙΑΙΤΙΟΣΕΣ
ΤΑΙΔΙΑΤΟΕΞΑΚΟΛΟΥ
ΘΕΙΝΘΑΝΑΤΟΝ

text: Translation: "Let no foreigner enter within the parapet and the partition which surrounds the Temple precincts. Anyone caught [violating] will be held accountable for his ensuing death." Today, the stone is preserved in Istanbul's Museum of Antiquities.

text: In 1936 a fragment of a similar Temple warning inscription was found. After 1967, archaeologists found that the wall extended all the way around the Temple Mount and is part of the city wall near the Lions' Gate. Thus, the Western Wall is not the only remaining part of the Temple Mount. Currently, Robinson's Arch (named after American Edward Robinson) remains as the beginning of an arch that spanned the gap between the top of the platform and the higher ground farther away. This had been used by the priests as an entrance. Commoners had entered through the still-extant, but now plugged, gates on the southern side which led through colonnades to the top of the platform. One of these colonnades is still extant and reachable through the Temple Mount. The Southern wall was designed as a grand entrance. Recent archeological digs have found thousands of mikvehs (ceremonial bathtubs) for the ritual purification of the worshipers, as well as a grand stairway leading to the now blocked entrance. Inside the walls, the platform was supported by a series of vaulted archways, now called Solomon's Stables, which still exist and whose current renovation by the Waqf is extremely controversial. The temple itself was constructed of imported white marble that gleamed in the daylight.

text: On September 25, 2007, Yuval Baruch, archaeologist with the Israeli Antiquities Authority announced the discovery of a quarry compound which may have provided King Herod with the stones to build his Temple on the Temple Mount. Coins, pottery and an iron stake found proved the date of the quarrying to be about 19 BCE. Archaeologist Ehud Netzer confirmed that the large outlines of the stone cuts is evidence that it was a massive public project worked by hundreds of slaves.[33]

text: The Magdala stone is thought to be a representation of the Second Temple carved before its destruction in the year 70.[34]

text:
Magdala Stone

Bar Kokhba tetradracm showing the Jerusalem Temple façade 132–135 CE

Arch of Titus showing spoils of Jerusalem Temple

The upper corner of Herod's temple colonnade with ancient Hebrew inscription

text:
The Warning Inscription found in 1871

A copy of the inscription found in 1871

Fragment of Second Temple Warning

The Trumpeting Place inscription, a stone (2.43 × 1 m) with Hebrew inscription "To the Trumpeting Place" excavated by Benjamin Mazar at the southern foot of the Temple Mount is believed to be a part of the Second Temple.

text: Second Temple Judaism[edit]

text: The period between the construction of the Second Temple in 515 BCE and its destruction by the Romans in 70 CE witnessed major historical upheavals and significant religious changes that would affect most subsequent Abrahamic religions. The origins of the authority of scripture, of the centrality of law and morality in religion, of the synagogue and of apocalyptic expectations for the future all developed in the Judaism of this period.