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RE: Big Bang
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A simple way of perceiving Particles is that they are products of FIELDS.
For every particle there is a corresponding field. It is `Probabilities` in the field, that carry energy and momentum from one place to another, that we call particles. This connection between particles and fields is called the Standard Model

Particles were found to have discrete levels of energy (quantised), the amounts were always `whole numbers`. An electron, for example, has 1.5 bits of energy! Hence particles are also called quantum. The study of particles and their fields is often called quantum physics.
Physicists hypothesise a series of particles, like the Higgs particles, which create scalar fields. The standard model cannot alone explain the mass of particles.



The following particles were created by the big bang, some are hypothesised. Lightweight particles (leptons):
half integral spins (1/2, 3/2,)

· Neutrino
· Electron
· Muon
· "Tau Heavy particles (hadrons):
· Quark Spin 1/2
· Proton and neutron:

Particles made of 3 quarks: 3 quarks, 1/2 integral spin
· Mesons made of quark and antiquark: integral spin
Gauge bosons (force carrying particles, between the leptons) would have been created: These have integral spin (0,1,2)

· Photon
· Strong
· Gravity.
· Weak nuclear
· Higgs
some other strange objects may have been produced,
· Magnetic Monopoles
· Cosmic Strings
· WIMPs

   
   

Particles and
antiparticles would have been created together. Antiparticles are the same as particles except they have the opposite electric charge. More matter was produced than antimatter; about one out of every billion particles of matter survives today!
The Higgs Particle is responsible for spontaneous symmetry breaking. Interaction of Higgs with all other particles leads to them acquiring MASS. GUTs predict that energies in excess of 10^5J are needed

Time = 10-43 seconds; Temp = 1032 The Planck epoch, During which all four fundamental forces were unified and "particles" as we known them could not have existed

At this time Gravity and the Strong Force are at the same scale. 1/R2is extremely large (R is very, very small)This is the time when our conventional physics breaks-down:· Particle can be created from the gravitational field
· One particle can have all the energy of the Universe
· Particle is same size as the Universe
·Even if we had the mathematical tools, could we understand this this physics?At the wall of the cosmos bubble, Supersymmetry was broken, making the bubble grow. Just inside this wall Higgs particles were releasing their energy as they decayed. So the bubble was gradually filled with energy. As bubbles of the "true vacuum" (with a nonzero Higgs field) percolate and grow, baryogenesis can occur at or near the bubble walls. Each cosmos would have had its own bang
Cosmic strings are supermassive relics of the early universe that were form at phase transitions. Other relic objects known as topological defects can also form at such transitions, including monopoles, textures and domain walls.
Guts unify the strong and electroweakquarks and antiquarks; leptons and antileptons; each can be transformed into each other

Time = 10-11 seconds; Temp = 3x1015 The GUT epoch,
When gravity had decoupled but the other three forces remained unified. The small excess of matter that makes up the universe today must have been created during this epoch,
At this time Gravity and the Strong force now have separated but the Weak force and the Electrostatic force still have the same magnitude.
When the symmetry is broken, forces are decoupled (a phase transition) in a specific manner so that the forces have now separate characteristic. This defines the physics of our Universe.

Simple Equations





-- Edited by Blobrana at 13:09, 2007-10-29

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BigBang
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An international team of astronomers from Spain and the UK have discovered what they claim is a texture - remnant from the Big Bang - and which they say, could provide a dramatic new insight into how the universe evolved following the Big Bang.
Textures are defects in the structure of the vacuum left over from the hot early universe.

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Title: On the Onset of Inflation in Loop Quantum Cosmology
Authors: Cristiano Germani (SISSA), William Nelson (KCL London), Mairi Sakellariadou (KCL London)
(Version v2)

Using a Liouville measure, similar to the one proposed recently by Gibbons and Turok, we investigate the probability that single-field inflation with a polynomial potential can last long enough to solve the shortcomings of the standard hot big bang model, within the semiclassical regime of loop quantum cosmology. We conclude that, for such a class of inflationary models and for natural values of the loop quantum cosmology parameters, a successful inflationary scenario is highly improbable.

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"I AM a heretic," Cristiano Germani announced to an audience of cosmologists last month. Few would disagree, as he is proposing a radical alternative to standard cosmology: a universe with no big bang creation moment, and no rapid inflation. Rather than a big bang, he suggests a slingshot.

Germani's alternative, unveiled at a cosmology conference at the University of Sussex, UK, last month, is based on a string-theory model in which the three visible dimensions of space are confined to the surface of a membrane, or brane, floating in a 10-dimensional space. The extra dimensions are wrapped up into a complex shape known as a Calabi-Yau space. The forces and particles in our 3D world are shadows of the motion of branes and strings in the Calabi-Yau space.
The problem with the simplest versions of this model is that the Calabi-Yau space is unstable, constantly vibrating and changing size.
Each wobble of the surface creates unwanted particles and extra forces in the universe - none of which have ever been observed. Attempts by string theorists to stabilise the space always warp it, forcing strange spikes and throats to pop out, Germani says. This warping, he believes, is the key to explaining the evolution of our universe.

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Title: Wave function of the Universe in the early stage of its evolution
Authors: Sergei P. Maydanyuk

In quantum cosmological models, constructed in the Friedmann-Robertson-Walker metrics, a nucleation of Universe with its further extension is described as a tunnelling transition (or leaving out) of wave through effective barrier between regions with small and large values of scale factor a at nonzero (or zero) energy. An approach for description of tunnelling with leaving outside consists in construction of wave function under choice of needed boundary condition. There are different ways for definition of the boundary condition that leads to different estimations of barrier penetrability and duration of the Universe nucleation. In given paper, with a purpose to describe a process of leaving of the wave from the tunnelling region outside accurately as possible, to construct the total wave function on the basis of its two partial solutions unambiguously, the tunnelling boundary condition (the total wave function must represent only the wave outgoing outside) is used at point of the wave leaving from the barrier outside, where the following definition for the wave is introduced: the wave is represented by such wave function, module of which is changed minimally under variation of scale factor a. A new method of direct (non-semiclassical) calculation of the total stationary wave function of the Universe is constructed, behaviour of this wave function in the tunnelling region, near point of leaving from the barrier outside and in the asymptotic region is analysed, a barrier penetrability is estimated. The following property has been observed: Period of oscillation of the wave function in the above-barrier region decreases uniformly with increasing of a. It has been proposed to use the oscillation period as a characteristics for estimation of dynamics of the Universe extension.

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Title: Emergence of Fluctuations from a Tachyonic Big Bang
Authors: Robert H. Brandenberger, Andrew R. Frey, Sugumi Kanno
(Version v2)

It has recently been speculated that the end state of a collapsing universe is a tachyonic big crunch. The time reversal of this process would be the emergence of an expanding universe from a tachyonic big bang. In this framework, we study the emergence of cosmological fluctuations. In particular, we compare the amplitude of the perturbations at the end of the tachyon phase with what would be obtained assuming the usual vacuum initial conditions. We find that cosmological fluctuations emerge in a thermal state. We comment on the relation to the trans-Planckian problem of inflationary cosmology.

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We all know the story, delivered in grade school textbooks across the country, of how the universe began. The Big Bang. Fourteen billion years ago. Space and time and everything, exploding into being in a flash, and still exploding as celestial bodies race apart across the cosmos.
Well, maybe so. But the Big Bang theory has taken its lumps in recent years.
Now, renegade physicists are making a new case. That it didn't all start in an instant. That there is no beginning, and no end. And those are fighting words in the halls of science.
This hour On Point: the big rumble over the Big Bang.

With:
·    Neil Turok, professor of mathematical physics at Cambridge University. He is the co-author of the new book, "Endless Universe: Beyond the Big Bang."
·    Alan Guth, professor of physics at the Massachusetts Institute of Technology. He is the author of "The Inflationary Universe: The Quest for a New Theory of Cosmic Origins."
·    Janna Levin, professor of physics and astronomy at Barnard College. She is the author of "How the Universe Got Its Spots: Diary of a Finite Time in a Finite Space."


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A leading expert on the Big Bang theory of creation has said he admires people who believe in God and has not ruled out His existence himself.
Dr Brian Cox, who was the science adviser for Danny Boyle's latest movie Sunshine, was speaking yesterday while in the capital to give a talk at the Edinburgh International Science Festival.
The renowned scientist, whose unique career path once led him to play keyboards for Nineties pop group D:Ream, also revealed the main character in Boyle's sci-fi blockbuster was loosely based on him.

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Cheng Chin will make a vacuum chamber in his laboratory the coldest place in Chicago in order to simulate the impossibly hot conditions that followed the big bang during the earliest moments of the universe.

"It turns out that matter at ultralow and ultrahigh temperatures might have something in common" -  Cheng Chin , an Assistant Professor in Physics at the University of Chicago.

Chin’s strategy for probing the formative moments of the early universe may also help boost the capability of quantum computers. The work is supported by a 2006 Packard Fellowship for Science and Engineering. As one of 20 new Fellows of the David and Lucile Packard Foundation, Chin will receive an unrestricted research grant of $625,000 over five years.
Astrophysicists believe that moments after the big bang, subatomic particles were spread evenly throughout a uniform environment that pervaded the universe.

"After billions of years, our universe is now far from uniform, with all kinds of complex structure: galaxies, planet systems, you and me. What is the origin of these complexities and when and how did they develop?" - Cheng Chin.

One scenario, called quantum fluctuation, describes a random process. Chin likened it to throwing beans on the floor. Any pattern that forms will arise entirely by chance. The alternative theory depends on what scientists call the Kibble-Zurek mechanism in which matter undergoes a quantum phase transition.
In the physics of everyday life, a phase transition occurs when snow flakes form out of cooling water vapour on a winter day. In the quantum world of subatomic particles, matter undergoes more exotic phase transitions under ultracold or ultrahot conditions. According to the laws of quantum physics, these transitions display a universal behavior regardless of whether they occur at absolute zero or under big-bang conditions of many billions of degrees.
Physicists are unable to recreate the big bang on Earth, but they can watch how uniformly distributed atoms develop patterns in an ultracold vacuum chamber. In his laboratory at the Gordon Center for Integrative Science, Chin will cool the atoms in a two-foot cylindrical vacuum chamber to billionths of a degree above absolute zero—minus 459.67 degrees Fahrenheit.
The cooled atoms will become a superfluid, an exotic state of matter that differs dramatically from the solids, liquids and gases that dominate everyday life. As the most uniform medium that technology can produce, the ultracold atoms in this superfluid will simulate how evenly distributed matter forms patterns under extreme conditions.
If the Kibble-Zurek process was operating after the big bang, voids and clumps of matter formed as the universe expanded and cooled over millions and billions of years, leading to the formation of galaxies interspersed by vast, nearly empty expanses of intergalactic space.

"Cosmological structures formed in this way will have predictable properties and are not fully random" -  Cheng Chin.

Chin controls the atoms in his experimental chamber by trapping them in the crossing pattern of infrared laser beams. These optical lattices hold ultracold atoms fast, like eggs in an egg crate, Chin said. In the second phase of his research program, Chin will attempt to develop these optical lattices to store and transmit information between large numbers of atoms.
In the world of computation, smaller is better. Quantum computers, if fully developed, would be far more powerful than conventional computers because they would use atoms instead of transistors as their basic components.

"There are many more tricks we can play on these atoms than on eggs or on any tangible object" - Chin Cheng Chin.

These tricks, or “quantum operations,” as scientists call them, could make it possible to tackle tasks with quantum computers that would otherwise prove impossible.
In particular, optical lattices can provide a way of maintaining a state of quantum coherence. In this state, all atoms are moving, spinning and tipping in perfect synchronicity.

"Think about setting a bunch of eggs to spin in sync. It is not an easy task! Quantum computation demands a very high degree of quantum coherence. Decoherence is essentially the No. 1 mechanism that limits the lifetime and the performance of a quantum computer. When quantum coherence is lost, you can only press the reset button and restart the computer"

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Background information:
In the inflationary theory, matter, antimatter, and photons were produced by the energy of the false vacuum, which was released following the phase transition. All of these particles consist of positive energy. This energy, however, is exactly balanced by the negative gravitational energy of everything pulling on everything else. In other words, the total energy of the universe is zero! It is remarkable that the universe consists of essentially nothing, but (fortunately for us) in positive and negative parts. You can easily see that gravity is associated with negative energy: If you drop a ball from rest (defined to be a state of zero energy), it gains energy of motion (kinetic energy) as it falls. But this gain is exactly balanced by a larger negative gravitational energy as it comes closer to Earth’s centre, so the sum of the two energies remains zero.
The idea of a zero-energy universe, together with inflation, suggests that all one needs is just a tiny bit of energy to get the whole thing started (that is, a tiny volume of energy in which inflation can begin). The universe then experiences inflationary expansion, but without creating net energy.

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Howard Smith is a senior astrophysicist at the Harvard-Smithsonian Center for Astrophysics, and author of "Let There Be Light: Modern Cosmology and Kabbalah, a New Conversation Between Science and Religion."
This was a remarkable year for astronomers studying the birth of the universe. Today we know with some certainty how the universe was created. The "big bang" theory captures the essentials: About 13.73 billion years ago, the cosmos we know was an infinitesimal speck. It exploded, expanded, and is now about 46 billion light-years in size.

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