* Astronomy

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: 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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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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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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