Archive for October 30, 2018

Hawking Points in the CMB Sky?

Posted in Astrohype, Bad Statistics, The Universe and Stuff with tags , on October 30, 2018 by telescoper

As I wait in Cardiff Airport for a flight back to civilization, I thought I’d briefly mention a paper that appeared on the arXiv this summer. The abstract of this paper (by Daniel An, Krzysztof A. Meissner and Roger Penrose) reads as follows:

This paper presents powerful observational evidence of anomalous individual points in the very early universe that appear to be sources of vast amounts of energy, revealed as specific signals found in the CMB sky. Though seemingly problematic for cosmic inflation, the existence of such anomalous points is an implication of conformal cyclic cosmology (CCC), as what could be the Hawking points of the theory, these being the effects of the final Hawking evaporation of supermassive black holes in the aeon prior to ours. Although of extremely low temperature at emission, in CCC this radiation is enormously concentrated by the conformal compression of the entire future of the black hole, resulting in a single point at the crossover into our current aeon, with the emission of vast numbers of particles, whose effects we appear to be seeing as the observed anomalous points. Remarkably, the B-mode location found by BICEP 2 is at one of these anomalous points.

The presence of Roger Penrose in the author list of this paper is no doubt a factor that contributed to the substantial amount of hype surrounding it, but although he is the originator of the Conformal Cyclic Cosmology I suspect he didn’t have anything to do with the data analysis presented in the paper as, great mathematician though he is, data analysis is not his forte.

I have to admit that I am very skeptical of the claims made in this paper – as I was in the previous case of claims of a evidence in favour of the Penrose model. In that case the analysis was flawed because it did not properly calculate the probability of the claimed anomalies in the standard model of cosmology. Moreover, the addition of a reference to BICEP2 at the end of the abstract doesn’t strengthen the case. The detection claimed by BICEP2 was (a) in polarization not in temperature and (b) is now known to be consistent with galactic foregrounds.

I will, however, hold my tongue on these claims, at least for the time being. I have an MSc student at Maynooth who is going to try to reproduce the analysis (which is not trivial, as the description in the paper is extremely vague). Watch this space.