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Author Topic:   Did a 5-D black hole brane event horizon make the universe?
RAZD
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From: the other end of the sidewalk
Joined: 03-14-2004


Message 1 of 2 (710235)
11-03-2013 2:00 PM


I came across this article from Banoosh
Goodbye Big Bang, Hello Black Hole? A New Theory Of The Universe’s Creation
Now I find Banoosh to be a resource of questionable trustworthyness (a lot of conspiracy theories for instance) so I looked up their links
quote:
You can read more about their research on this prepublished Arxiv paper. The Arxiv entry does not specify if the paper has been submitted to any peer-reviewed scientific journals for publication.
Source: Nature
The Arvix link is short:
quote:
Out of the White Hole: A Holographic Origin for the Big Bang
Razieh Pourhasan, Niayesh Afshordi, Robert B. Mann
(Submitted on 5 Sep 2013 (v1), last revised 22 Sep 2013 (this version, v2))
While most of the singularities of General Relativity are expected to be safely hidden behind event horizons by the cosmic censorship conjecture, we happen to live in the causal future of the classical big bang singularity, whose resolution constitutes the active field of early universe cosmology. Could the big bang be also hidden behind a causal horizon, making us immune to the decadent impacts of a naked singularity? We describe a braneworld description of cosmology with both 4d induced and 5d bulk gravity (otherwise known as Dvali-Gabadadze-Porati, or DGP model), which exhibits this feature: The universe emerges as a spherical 3-brane out of the formation of a 5d Schwarzschild black hole. In particular, we show that a pressure singularity of the holographic fluid, discovered earlier, happens inside the white hole horizon, and thus need not be real or imply any pathology. Furthermore, we outline a novel mechanism through which any thermal atmosphere for the brane, with comoving temperature of 20% of the 5D Planck mass can induce scale-invariant primordial curvature perturbations on the brane, circumventing the need for a separate process (such as cosmic inflation) to explain current cosmological observations. Finally, we note that 5D space-time is asymptotically flat, and thus potentially allows an S-matrix or (after minor modifications) AdS/CFT description of the cosmological big bang.
Comments: 16 pages, 3 figures
That is just the abstract, but there is a link to download the PDF version -- note this is on the technical side ...
The other link is to the Nature article: Did a hyper-black hole spawn the Universe?
quote:
Big Bang was mirage from collapsing higher-dimensional star, theorists propose.
It could be time to bid the Big Bang bye-bye. Cosmologists have speculated that the Universe formed from the debris ejected when a four-dimensional star collapsed into a black hole a scenario that would help to explain why the cosmos seems to be so uniform in all directions.
In a paper posted last week on the arXiv preprint server(1), Afshordi and his colleagues turn their attention to a proposal(2) made in 2000 by a team including Gia Dvali, a physicist now at the Ludwig Maximilians University in Munich, Germany. In that model, our three-dimensional (3D) Universe is a membrane, or brane, that floats through a ‘bulk universe’ that has four spatial dimensions.
In our Universe, a black hole is bounded by a spherical surface called an event horizon. Whereas in ordinary three-dimensional space it takes a two-dimensional object (a surface) to create a boundary inside a black hole, in the bulk universe the event horizon of a 4D black hole would be a 3D object a shape called a hypersphere. When Afshordi’s team modelled the death of a 4D star, they found that the ejected material would form a 3D brane surrounding that 3D event horizon, and slowly expand.
The picture has some problems, however. Earlier this year, the European Space Agency's Planck space observatory released data that mapped the slight temperature fluctuations in the cosmic microwave background the relic radiation that carries imprints of the Universe’s early moments. The observed patterns matched predictions made by the standard Big Bang model and inflation, but the black-hole model deviates from Planck's observations by about 4%. Hoping to resolve the discrepancy, Afshordi says that his is now refining its model.
Despite the mismatch, Dvali praises the ingenious way in which the team threw out the Big Bang model. The singularity is the most fundamental problem in cosmology and they have rewritten history so that we never encountered it, he says. Whereas the Planck results prove that inflation is correct, they leave open the question of how inflation happened, Dvali adds. The study could help to show how inflation is triggered by the motion of the Universe through a higher-dimensional reality, he says.
And then the "Bulk Universe" is a "bulk brane" around a black hole in a mega-bulk universe ... and it's turtles all the way down ... or you can think of it as a shell game where each universe is a "russian doll" inside another "russian doll" ...
Enjoy

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AdminNosy
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From: Vancouver, BC, Canada
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Message 2 of 2 (710237)
11-03-2013 2:19 PM


Thread Copied to Big Bang and Cosmology Forum
Thread copied to the Did a 5-D black hole brane event horizon make the universe? thread in the Big Bang and Cosmology forum, this copy of the thread has been closed.

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