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==from conclusions section on page 4 of Barrau Linsefors June paper==
V. REBIRTH OF THE UNIVERSE AND TESTS OF THE MODEL
In the far future, huge patches of our universe, with radii larger than the Hubble scale, will be completely empty. They will be pure dS spaces. If the model suggested in this work is correct, these empty spaces will give birth to new universe through the process of spontaneous symmetry breaking described above. When this leads to a contraction, which will inevitably occur, a new universe filled with radiation – and then matter – will appear.
It should be emphasized that time always exists in this model in the sense of a light cone structure. The quantum breaking of the classical symmetry just selects a preferred slicing that corresponds to either a contracting or an expanding solution. We are not suggesting that time is emergent, or that it changes direction.
Is it possible to test this scenario? First, it should be pointed out that no new “theory” is suggested here. We just link together all the consequences of already accepted or assumed models. The two main ingredients of our proposal are the bounce and the cosmological constant. Both can be tested and, in principle, if both are validated the suggest scenario comes somehow automatically.
As far as the bounce in concerned, different observational footprints can be expected, even beyond LQC (see, e.g., [28] and references therein). As far as the interpretation of the acceleration of the Universe by a cosmological constant (or not) is concerned, many experiments are of course devoted to this issue, in particular the LSST telescope and the Euclid satellite.
One step further, this specific scenario of filling the Universe with dS radiation (beyond the bounce and cosmological constant ingredients) can be falsified. Let us consider an example. If our suggestion is correct, one does not expect complex structures in the contracting branch, there is no way to form stars and subsequent black holes. However coalescence of black holes in the contracting phase have been shown to be detectable [29]. If such circles were to be detected, this would disprove our proposal.
...
This simple model builds on the specific properties of dS spaces and bouncing cosmologies to suggest an original new scenario which does not require any assumption about the initial matter content of the Universe. Everything happens because of the cosmological constant and quantum effects. Particle physics enters the game for the details of the dynamics around the bounce, but the main picture just relies on ”vacuum” properties. There are no divergences, no origin of time, and no problem of initial values for the content of the Universe.
==endquote==
http://arxiv.org/abs/1406.3706
Our Universe from the cosmological constant
Aurelien Barrau, Linda Linsefors
(Submitted on 14 Jun 2014)
In this article, we consider a bouncing Universe, as described for example by Loop Quantum Cosmology. If the current acceleration is due to a true cosmological constant, this constant is naturally conserved through the bounce and the Universe should also be in a (contracting) de Sitter phase in the remote past. We investigate here the possibility that the de Sitter temperature in the contracting branch fills the Universe with radiation and causes the bounce and the subsequent inflation and reheating. We also consider the possibility that this gives rise to a cyclic model of the Universe and suggest some possible tests.
5 pages
==my comment, merely to clarify one of their points==
MATTER and/or radiation by its very existence breaks the symmetry of deSitter geometry by selecting a preferred slicing. We already see this sort of thing with the CMB ancient light which selects a preferred foliation in the standard Friedman cosmic model. The "symmetry breaking" here is a GR symmetry breaking rather than the particle physics kind. One is breaking the diffeo invariance/general covariance.
V. REBIRTH OF THE UNIVERSE AND TESTS OF THE MODEL
In the far future, huge patches of our universe, with radii larger than the Hubble scale, will be completely empty. They will be pure dS spaces. If the model suggested in this work is correct, these empty spaces will give birth to new universe through the process of spontaneous symmetry breaking described above. When this leads to a contraction, which will inevitably occur, a new universe filled with radiation – and then matter – will appear.
It should be emphasized that time always exists in this model in the sense of a light cone structure. The quantum breaking of the classical symmetry just selects a preferred slicing that corresponds to either a contracting or an expanding solution. We are not suggesting that time is emergent, or that it changes direction.
Is it possible to test this scenario? First, it should be pointed out that no new “theory” is suggested here. We just link together all the consequences of already accepted or assumed models. The two main ingredients of our proposal are the bounce and the cosmological constant. Both can be tested and, in principle, if both are validated the suggest scenario comes somehow automatically.
As far as the bounce in concerned, different observational footprints can be expected, even beyond LQC (see, e.g., [28] and references therein). As far as the interpretation of the acceleration of the Universe by a cosmological constant (or not) is concerned, many experiments are of course devoted to this issue, in particular the LSST telescope and the Euclid satellite.
One step further, this specific scenario of filling the Universe with dS radiation (beyond the bounce and cosmological constant ingredients) can be falsified. Let us consider an example. If our suggestion is correct, one does not expect complex structures in the contracting branch, there is no way to form stars and subsequent black holes. However coalescence of black holes in the contracting phase have been shown to be detectable [29]. If such circles were to be detected, this would disprove our proposal.
...
This simple model builds on the specific properties of dS spaces and bouncing cosmologies to suggest an original new scenario which does not require any assumption about the initial matter content of the Universe. Everything happens because of the cosmological constant and quantum effects. Particle physics enters the game for the details of the dynamics around the bounce, but the main picture just relies on ”vacuum” properties. There are no divergences, no origin of time, and no problem of initial values for the content of the Universe.
==endquote==
http://arxiv.org/abs/1406.3706
Our Universe from the cosmological constant
Aurelien Barrau, Linda Linsefors
(Submitted on 14 Jun 2014)
In this article, we consider a bouncing Universe, as described for example by Loop Quantum Cosmology. If the current acceleration is due to a true cosmological constant, this constant is naturally conserved through the bounce and the Universe should also be in a (contracting) de Sitter phase in the remote past. We investigate here the possibility that the de Sitter temperature in the contracting branch fills the Universe with radiation and causes the bounce and the subsequent inflation and reheating. We also consider the possibility that this gives rise to a cyclic model of the Universe and suggest some possible tests.
5 pages
==my comment, merely to clarify one of their points==
MATTER and/or radiation by its very existence breaks the symmetry of deSitter geometry by selecting a preferred slicing. We already see this sort of thing with the CMB ancient light which selects a preferred foliation in the standard Friedman cosmic model. The "symmetry breaking" here is a GR symmetry breaking rather than the particle physics kind. One is breaking the diffeo invariance/general covariance.
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