* Astronomy

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RE: Big Bang

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Listening to the Big Bang - in high fidelity

A decade ago, spurred by a question for a fifth-grade science project, University of Washington physicist John Cramer devised an audio recreation of the Big Bang that started our universe nearly 14 billion years ago.
Now, armed with more sophisticated data from a satellite mission observing the cosmic microwave background - a faint glow in the universe that acts as sort of a fossilised fingerprint of the Big Bang - Cramer has produced new recordings that fill in higher frequencies to create a fuller and richer sound.
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The first fractions of a second after the Big Bang

Scientists are about to release new pictures of the "oldest light" in the Universe compiled by Europe's Planck satellite. The images will give us unprecedented insights into the origins and evolution of the cosmos.
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CSIRO telescope takes temperature of Universe

Astronomers using a CSIRO radio telescope have taken the Universe's temperature, and have found that it has cooled down just the way the Big Bang theory predicts.
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Title: A fully quantum model of Big Bang
Authors: Sergei P. Maydanyuk, Antonino Del Popolo, Vladislav S. Olkhovskyans

In the paper the closed Friedmann-Robertson-Walker model with quantisation in the presence of the positive cosmological constant and radiation is studied. For analysis of tunnelling probability for birth of an asymptotically deSitter, inflationary Universe as a function of the radiation energy a new definition of a "free" wave propagating inside strong fields is proposed. On such a basis, tunnelling boundary condition is corrected, penetrability and reflection concerning to the barrier are calculated in fully quantum stationary approach. For the first time non-zero interference between the incident and reflected waves has been taken into account which turns out to play important role inside cosmological potentials and could be explained by non-locality of barriers in quantum mechanics. Inside whole region of energy of radiation the tunnelling probability for the birth of the inflationary Universe is found to be close to its value obtained in semiclassical approach. The reflection from the barrier is determined for the first time (which is essentially differs on 1 at the energy of radiation close to the barrier height). The proposed method could be easily generalized on the cosmological models with the barriers of arbitrary shape, that has been demonstrated for the FRW-model with included Chaplygin gas. Result is stable for variations of the studied barriers, accuracy are found to be 11--18 digits for all coefficients and energies below the barrier height.

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Big Bang theory challenged by big chill

The start of the Universe should be modelled not as a Big Bang but more like water freezing into ice, according to a team of theoretical physicists at the University of Melbourne and RMIT University.
They have suggested that by investigating the cracks and crevices common to all crystals - including ice - our understanding of the nature of the Universe could be revolutionised.
Lead researcher on the project, James Quach said current theorising is the latest in a long quest by humans to understand the origins and nature of the Universe.
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This is recording of a lecture by Sir Roger Penrose held at the Isaac Newton Institute for Mathematical Sciences on the 7th November 2005.

Sir Roger Penrose (born 8 August 1931; OM, FRS), is an English mathematical physicist, recreational mathematician, philosopher and Emeritus Rouse Ball Professor of Mathematics at the Mathematical Institute of the University of Oxford, as well as Emeritus Fellow of Wadham College.

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The Big Bang: Origins of our Universe

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'A Universe From Nothing' by Lawrence Krauss, AAI 2009

Lawrence Krauss gives a talk on our current picture of the universe, how it will end, and how it could have come from nothing. Krauss is the author of many best-selling books on Physics and Cosmology, including "The Physics of Star Trek."

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Title: Expanding universe as a classical solution in the Lorentzian matrix model for nonperturbative superstring theory
Authors: Sang-Woo Kim, Jun Nishimura, Asato Tsuchiya

Recently we have shown by Monte Carlo simulation that expanding (3+1)-dimensional universe appears dynamically from a Lorentzian matrix model for type IIB superstring theory in (9+1)-dimensions. The mechanism for the spontaneous breaking of rotational symmetry relies crucially on the noncommutative nature of the space. Here we study the classical equations of motion as a complementary approach. In particular, we find a unique class of SO(3) symmetric solutions, which exhibits the time-dependence compatible with the expanding universe. The space-space noncommutativity is exactly zero, whereas the space-time noncommutativity becomes significant only towards the end of the expansion. We interpret the Monte Carlo results and the classical solution as describing the behaviour of the model at earlier time and at later time, respectively.

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