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Conformal Cyclic Cosmology

  1. Jul 16, 2013 #1
    Hey everyone,

    I wanted to share this new interview I found with Roger Penrose wherein he discusses his theory of conformal cyclic cosmology:


    I was wondering, are you convinced by his theory? I find it intriguing but I'm skeptical of the notion of information loss, or "transcending" the second law.
  2. jcsd
  3. Jul 17, 2013 #2
    My impression is that Penrose has not convinced the community of his model.

    I would hazard a guess that most will say they haven't paid any attention to it at all, those that have think its at best a neat idea but not convincing enough. Certainly the initial empirical evidence he presented was not bought by the community, it was totally shot down in fact.
    However since then K Meisner et al who are bit more respected in the field I believe did have some positive things to say about CCC, even agreeing there is evidence for it in WMAP data. I dont know if they still think that after PLanck .

    One of the biggest assumption in the theory is that all matter decays to radiation, but proton decay for example is ruled out for about 10^33 years. Of course with 10^100 years for black hole decay I guess Penrsoe has a lot of time to play with. But he still has to assume something like the Higgs field itself decays, However he doesnt have to assume extra dimensions or supersymmetry or even any novel quantum gravity affects.
  4. Jul 17, 2013 #3
    I also think i should add that there many proposals for a pre big bang scenario and CCC is one of them. But in my opinion there are only two models that have attracted a significantly wider community of researchers. One is loop quantum cosmology and the other is eternal inflation. both of these have many researchers around the world publishing a lot of papers every year.
    Of course that doesn't mean either of these models are correct or that CCC is wrong, but if you want to know what has attracted researchers and what has not in terms of these sorts of scenarios that's my take. I wonder if others agree?
  5. Jul 18, 2013 #4


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    This idea has been severely tainted by an exceedingly bad paper published about it a few years ago, where Penrose and Gurzadyan misunderstood the basic statistics of the CMB, and used that misunderstanding in an attempt to claim evidence for their idea.

    As it stands, however, it's a pie-in-the-sky idea with no supporting evidence for it, and nearly all such ideas are wrong.
  6. Jul 23, 2013 #5
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