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1

I’m not sure I fully understand the question but I’ll try. The “curious one” says that if the initial condition is picked at random then it should be a state of thermal equilibrium (maximum entropy) since the overwhelming majority of states look equilibrium-like. Now there has to be something wrong with that in the cosmological context. States of thermal ...


0

The problem stemmed from having to deal with how such a vast region of space had such a fine tuned uniformity. Without inflation that same volume could not have maintained the same uniformity once you consider the mean free path between the particles. Thermal equilibrium requires not only a high temperature. It also requires a sufficient density to allow the ...


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The Big Crunch is a prediction of the FLRW metric when the matter/energy density is above the critical value i.e. a closed universe. The FLRW metric gives us the scale factor of the universe as a function of comoving time, and for a closed universe the scale factor increases smoothly with time from zero at the Big Bang, through a maximum and back to zero at ...


6

OK, I found a recent link: Planck versus BICEP2 Despite the new data, the collaboration did not give any insights into the recent controversy surrounding the possible detection of primordial "B-mode" polarization of the CMB by astronomers working on the BICEP2 telescope. If verified, the BICEP2 observation would be "smoking-gun" evidence for the rapid ...


5

In this link, the contradiction is "explained": The tremendous expansion greatly dilutes any initial curvature. Think, for example, of standing on a basketball. It would be obvious that you are standing on a (2-dimensional) curved surface. Now imagine expanding the basketball to the size of the Earth. As you stand on it now, it will appear to be flat ...


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Does this mean that matter/antimatter (say, an electron and a positron) may be created and annihilate each other, This is called vacuum fluctuations as stated by Quantum Field Theory. In this case energy has to be supplied so that the electron positron pair out of the vacuum would materialize. This does happen at laboratory energies in experiments with ...


3

The inflaton certainly interacts with SM fields. During inflation, the energy density of the Universe is dominated by the potential energy of the infaton and the Universe cools. At the end of inflation, the inflaton should decay to ordinary particles (electrons, photons etc.) in a process known as reheating. After reheating, the big bang begins in earnest. ...


0

I think you misinterpreted the quote. Here it is in full: To explain, for example, how the universe could have smoothed itself out to achieve the uniformity of temperature that we observe today in the cosmic background radiation, one finds that in the context of the standard Big Bang theory, it would be necessary for energy and information to be ...


0

The speed of light is constant relative to the fabric of space, but when space itself is expanding, the speed of lighg, as measures by an external obsrver can be larger than c. This is a known fact in general relativity (special relativity doesnt consider such possibility). Update: what has slowed down was the expansion of space itself, with drags the light ...



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