Echos of a bygone Aeon

[ydoaPs]

http://www.bbc.co.uk/news/science-environment-11837869

http://arxiv.org/abs/1011.3706

 

The BBC has an article with a link to unpublished research suggesting that microwave background may hold clues to events that happened prior to our Big Bang. Thoughts?

[louis wu]

Well Penrose has lots of previous in trying to do away with inflation.

2006 penrose paper

I read this 2006 paper when it appeared and thought at the time that he was reaching a bit.

If the evidence he claims to have found is confirmed it will be a remarkable finding, and make the 'axis of evil' look like an insignificant artefact of synchrotron radiation in the Galactic Plane.

[ajb]

Thoughts?

 

This is outside my area of expertise. That said the initial results seem quite clear and interesting. I now await the reply from experts in cosmology and the physics of the early universe. There will be people re-examining Penrose and Gurzadyan's analysis and conclusions.

 

Anything that might shake the lambda CDM model should be fully investigated.

[Martin]

http://arxiv.org/abs/1012.1268

A search for concentric circles in the 7-year WMAP temperature sky maps

I. K. Wehus, H. K. Eriksen

 

http://arxiv.org/abs/1012.1305

No evidence for anomalously low variance circles on the sky

Adam Moss, Douglas Scott, James P. Zibin

 

 

 

Sean Carroll pointed these out. Looks like Penrose circles not confirmed.

http://blogs.discovermagazine.com/cosmicvariance/2010/12/07/penroses-cyclic-cosmology/

[ydoaPs]

Sean Carroll pointed these out. Looks like Penrose circles not confirmed.

http://blogs.discovermagazine.com/cosmicvariance/2010/12/07/penroses-cyclic-cosmology/

That's rather interesting with the abstract of Penrose's paper saying he had indeed found the circles.

 

edit:

The first one said they DID find the circles, yet it somehow doesn't agree with Penrose. What's the deal?

 

The second paper also found the circles.

 

edit2:

What these papers seem to say, despite the title of the second one, is that the circles DO exist, but they are not evidence exclusively of a cyclic cosmology. If that is the case, then this really wouldn't be a problem with the current model considering the background radiation analysis showing large scale euclidean nature of the universe. It seems to me that the cyclic proponents need to account for why our universe is flat. Doesn't a flat universe indicate that the universe is either the last cycle or the only one?

Edited December 7, 2010 by ydoaPs

[louis wu]

That's rather interesting with the abstract of Penrose's paper saying he had indeed found the circles.edit:The first one said they DID find the circles, yet it somehow doesn't agree with Penrose. What's the deal?The second paper also found the circles.edit2:What these papers seem to say, despite the title of the second one, is that the circles DO exist, but they are not evidence exclusively of a cyclic cosmology. If that is the case, then this really wouldn't be a problem with the current model considering the background radiation analysis showing large scale euclidean nature of the universe. It seems to me that the cyclic proponents need to account for why our universe is flat. Doesn't a flat universe indicate that the universe is either the last cycle or the only one?

Is it settled that the universe is now and will forever be euclidean, even considering the actions of dark energy?

In some circles it is a consistent meme that the universe will inevitably approach the parameters of a de Sitter universe. I would struggle to consider a de Sitter universe euclidean.

Edited December 8, 2010 by louis wu

[Martin]

I should have spoken more precisely. As I understand it they found that amount of patterning can occur randomly. As one paper said, to the extent that Penrose found concentric circles you could just as well find triangles or squares. There will always be randomly occurring patterns but it does not mean anything. So the papers contested the claim that the findings were significant.

 

====================================================================

 

I may be mistaken. PENROSE AND GURZADYAN posted a second paper today, answering their critics and maitaining that the observed patterning is significant.

 

 

http://arxiv.org/abs/1012.1486

More on the low variance circles in CMB sky

V.G.Gurzadyan, R.Penrose

2 pages

(Submitted on 7 Dec 2010)

"Two groups [3,4] have confirmed the results of our paper concerning the actual existence of low variance circles in the cosmic microwave background (CMB) sky. They also point out that the effect does not contradict the LCDM model - a matter which is not in dispute. We point out two discrepancies between their treatment and ours, however, one technical, the other having to do with the very understanding of what constitutes a Gaussian random signal. Both groups simulate maps using the CMB power spectrum for LCDM, while we simulate a pure Gaussian sky plus the WMAP's noise, which points out the contradiction with a common statement [3] that 'CMB signal is random noise of Gaussian nature'. For as it was shown in [5], the random component is a minor one in the CMB signal, namely, about 0.2. Accordingly, the circles we saw are a real structure of the CMB sky and they are not of a random Gaussian nature. Although the structures studied certainly cannot contradict the power spectrum, which is well fitted by LCDM model, we particularly emphasize that the low variance circles occur in concentric families, and this key fact cannot be explained as a purely random effect. It is, however a clear prediction of conformal cyclic cosmology."

Edited December 8, 2010 by Martin