In the past two years work by Ashtekar and others in Loop cosmology has modified the LQG dynamics. Two postdocs at Portsmouth, one of whom is an Ashtekar PhD, have recently studied the Schwarzschild blackhole using the improved dynamics. They got some new results which seem to point in the direction of a bounce.(adsbygoogle = window.adsbygoogle || []).push({});

http://arxiv.org/abs/0709.2129

Loop Quantum Dynamics of the Schwarzschild Interior

Christian G. Boehmer, Kevin Vandersloot

15 pages, 13 figures

(Submitted on 13 Sep 2007)

"We examine the Schwarzschild interior of a black hole, incorporating quantum gravitational modifications due to loop quantum gravity. We consider an improved loop quantization using techniques that have proven successful in loop quantum cosmology. The central Schwarzschild singularity is resolved and the implications for the fate of an in-falling test particle in the interior region is discussed.The singularity is replaced by a Nariai type Universe.We discuss the resulting conformal diagram, providing a clear geometrical interpretation of the quantum effects.

For some general background here is Andy Hamilton page on Schwarzschild black/white holes

http://casa.colorado.edu/~ajsh/schww.html

One of Hamilton's conformal diagrams resembles one of the conformal diagrams in Böhmer Vandersloot's paper.

Sidenote: if you are a US new QG PhD you pretty much have to go to Canada or Europe to continue career. (string monopolizes postdocs in the US, so no postdoc openings for QG in US). What Kevin did was win a coveted Curie postdoctoral fellowship from the ESF (European Science Foundation) which is normally just for UK and European applicants. He could choose any place in UK or Europe to take the fellowship and he chose Portsmouth.

Portsmouth is strong in QG and Cosmology and also QC phenomenology (testing by observation). Roy Maartens is there and there is a special institute. So Portsmouth is a good place to go and it's not surprising that two postdocs like Böhmer and Vandersloot go there and meet up.

I'm still trying to figure out what Kevin and Christian's new paper concludes about what happens in a black hole. The results, which are suggestive rather than conclusive, overrides the "singularity" which occurs in classical GR. They find two possibilities, both needing further exploration.

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UPDATE TO REPLY TO NEXT POST:

Hi Kurt, thanks for the NewSci link--their article is a general introduction to the "baby universe" topic--and has pictures.

You commented:

That is certainly right and a BOOK has even been written about it called kurt.physics said: ↑This theory of a specific type of universe being connected to a black hole isnt relatively new theory (by relative, im referring to within the last 10 years).The Life of the Cosmos, plus also many scholarly papers.

What is new about Kevin and Christian's work is they do new analysis, use a new QG dynamics, and run a lot of numerical work on the computer. They do not START with the idea that there is a bounce-baby, they start with a leading candidate model---the best currently available to replace GR at singularities IMO---and they SEE if there is a bounce. In fact in one case they do not get it, and in the other case they get the bounce. So they are trying out different versions of a LQG model blackhole to see what actually happens (with that model).

The idea of a bounce-baby is not new (I think John Wheeler proposed it several decades ago) but now we are seeing more progress studying the details.

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# New view of blackhole bounce

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