A Instability of Cosmology with Quantum Corrections

David Miller
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A good year ago, quantum corrections have been proposed to the very early Universe. It was concluded that these quantum corrections contain a precise estimation for the cosmological constant and the so-called radiation term. The authors even have interpreted the latter as evading the big-bang singularity and determining an infinite age of the Universe. This was mentioned in science and social media for instance http://phys.org/news/2015-02-big-quantum-equation-universe.html

This proposal was sharply criticized in http://arxiv.org/pdf/1505.03070.pdf

Instead of struggling with the correctness of the given approach and to retry to rederive the mathematical equations as partly done in http://arxiv.org/pdf/1505.03070.pdf, Tawfik et al. wanted to check the so-called "perturbative instability", which based is on whether or not any added perturbation alters at a later time. The universe we live in and the one described by such world approach is apparently stable despite its accelerated expansion. Thus the claimed world model should absolve the
"stability check", http://arxiv.org/pdf/1603.03032.pdf and Physical Review D
https://journals.aps.org/prd/abstract/10.1103/PhysRevD.93.063526 show that the "Cosmology with quantum equation" is simply unstable.
 
Thanks Admin! I ll reword the post
 
The recent paper by Tawfik et al. entitled with "Perturbative Instability of Cosmology from Quantum Potential" https://journals.aps.org/prd/abstract/10.1103/PhysRevD.93.063526 shows that Ali and Das, "Cosmology from quantum potential," http://arxiv.org/abs/1404.3093 which was commented in https://www.physicsforums.com/threads/ali-and-das-cosmology-from-quantum-potential.797183/ describes an unstable Universe. The perturbative instability is nicely written in Tawfik et al.'s paper.

I'm not a quite familiar specialist on such "instabilities checks", but from a brief inspection it looks to me that the recent paper simply revises the earlier one. Should we now ignore "Cosmology from quantum potential," http://arxiv.org/abs/1404.3093?

Is this impression correct?
 
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Hi, I’m pretty new to cosmology and I’m trying to get my head around the Big Bang and the potential infinite extent of the universe as a whole. There’s lots of misleading info out there but this forum and a few others have helped me and I just wanted to check I have the right idea. The Big Bang was the creation of space and time. At this instant t=0 space was infinite in size but the scale factor was zero. I’m picturing it (hopefully correctly) like an excel spreadsheet with infinite...
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