Monday, May 25, 2009

The danger with cosmological arguments

I had said it before, but a new article, well, in fact two of them, almost consecutives, in arxiv, commented in the arxiv blog, brings again alive the question.

My point was to state that although cosmology is a legitimate topic, and that it has seen a fructiferous interplay with particle physic(in, for example, the BBN-big bang nucleosynthesis) cosmological observations are subject to many uncertainties. In my opinion that implies that one shouldn't sacrify the coherence and "physic common sense" of a theory it if not match some particular cosmological observation.

In particular I find that the problem of the cosmological constant is not enough reason to go into the landscape/anthropic scenery.

In the article Giant Lens May Be Distorting Echo of the Big Bang, based in the arsiv paper A Heliosheath Model for the Origin of the CMB Quadrupole Moment is stated that the analysis of the data send by the sputnik satellites when the left the solar system reveals that possibly the observed anisotropies in the CMB observed by COBE and WMAP could have an astrophysical origin, in the out shells of the solar system, and they don´t reflect a real cosmological anisotropy. that is certainly very important because the recently launched PLANCK and HERSCHELL satellites are supposed to make a better measure of that polarizations. Supossedly the sensitivity of that measures would allow to tests some models of inflation. But if the measured quantities are of astrophysical origin the utility of the whole busines would change radically.

Today other article claim to have a model for the accelerated cosmological expansion baed on five foreces actin in long ranges (but in not shor ones). Certainly it is not the first, and it will not be the last, article who proposes an alternative to the cosmological constant. For example, as far as I know models based in "quintaessence" are not ruled out. I personally find unnecessary to go into the landscape when it is reasonable to expect better explanations for the observed expansion of the universe. And, well, as the previous article clearly shows it is a good idea to be cautious about the accuracy and veracity of cosmological data.

2 comments:

Kea said...

Some of us, who have been following the Riofrio cosmology for years, know that there is no /\ in cosmology. Check out the papers of Starkman on a reanalysis of WMAP III data with the dodgy astrophysical component removed. The standard picture does not match the data. Let me repeat that in capital letters - the standard cosmology DOES NOT MATCH THE DATA.

Javier said...

Hum, ok, I'll search tehm and I'll give thm a llok.

But what you say I infer that they were already somewhat aware of the astrophysical influence, isn' it?

That sounds interesting. I thought that the arxiv paper i cited was the first to worry about it.