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If we are to believe zellers store locator the great mathematician and physicist Roger Penrose, and astrophysicist and cosmologist Vahe G. Gurzadyan, the WMAP data on the CMB contain traces of before Big Bang, predicted by a cyclic cosmological model.
The new idea of Roger Penrose is called cyclic zellers store locator cosmology consistent (CCC) and is crazy enough to be exact, according to the well-known expression of Niels Bohr. Sir Penrose zellers store locator is not a stranger. It has profoundly zellers store locator contributed to the revival of general relativity in the 1960s and 1970s, making use of the concepts and methods of algebraic geometry and differential topology. We owe him the first singularity theorem concerning the physics of black holes. But it is also famous for another singularity theorem in relativistic cosmology that one, demonstrated in collaboration with Stephen Hawking. zellers store locator
This theorem shows that if we remain within the classical framework of the equations describing the geometry of space-time, an initial cosmological singularity should indeed be present at the beginning zellers store locator of the history of our observable universe. This singularity is a real beginning for space and time and therefore makes meaningless the idea of a Big Bang before under the laws of classical physics.
Penrose zellers store locator is not a grand master of the physical zellers store locator space-time. It is obviously attacked the formidable problem of merging concepts and equations of quantum physics with that and those of relativistic physics. It has proposed that its twistor theory (twistors in English) zellers store locator and of spin networks. The first has been extensively applied to string theory within the / CFT correspondence AdS recent years. The second, meanwhile, is at the base of loop quantum gravity (LQG).
Recall that these two theories are serious candidates for quantum zellers store locator theory of gravitation, which is essential to be able, perhaps, to answer questions like: "What was there before the Big Bang? "Or" How the universe and space-time were they born? ". Entropy, a problem in cosmology
However, Penrose does not hide that he does not believe much in string theory with extra spatial dimensions. He is not satisfied with either of what is becoming the standard model of cosmology, namely zellers store locator the theory zellers store locator of inflation. She actually passed several tests victoriously zellers store locator through measurements performed by WMAP CMB but is not yet proven. This theory of inflation was introduced in the early 1980s by theorists such as Alan Guth and Andrei Linde, to solve problems and puzzles in the context of relativistic cosmology based on high energy zellers store locator physics.
Sir Roger has always found misleading the solutions provided by the theory of inflation, zellers store locator in part because it did not solve the problem of very particular initial state of the universe in conjunction with the second principle of thermodynamics.
The status of the second law of thermodynamics in relativistic zellers store locator cosmology is old and can be traced back to the work of Father Lemaitre and especially those of Richard Tolman. Through the reflections zellers store locator of John Wheeler and ideas of Bekenstein, this status will be at the root of the discovery by Stephen zellers store locator Hawking evaporation zellers store locator of black holes and the famous Bekenstein-Hawking formula giving the entropy of a black hole .
Tolman was concerned during the 1930s universe Friedmann model in which a closed universe cyclically passed through phases of contraction zellers store locator and expansion, and for all eternity, without beginning or end.
This strange reminiscence of Hindu cosmology does not however take into account zellers store locator the second zellers store locator law of thermodynamics, wishing that the entropy is increasing in a closed system. According to calculations Tolman, each beginning of a new cycle of the universe had yet to be accompanied by an increase in the entropy of the matter and radiation it contained. However, the entropy of the universe is finite and actually quite low, it did not fit with the notion of eternal cycles.
We now know that our universe is accelerated because of its content dark energy expansion. It seems that its geometry is very close to being flat, that is to say that we are unable to determine whether we are in a closed finite universe or in a universe of infinite size but already growing. In all cases, zellers store locator if the dark energy is well described by a cosmological constant or a field of q
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