On a possible nonequilibrium imprint in the cosmic background at low frequencies

Journal
Date Issued
2020
Author(s)
Marco Baiesi
•
•
Livia Conti
•
Gianmaria Falasco
•
Christian Maes
•
Lamberto Rondoni
•
Tiziana Trombetti
DOI
Abstract
The cosmic background radiation has been observed to deviate from the Planck law expected from a blackbody at $\sim$ 2.7 K at frequencies below $\sim 3$ GHz. We discuss the abundance of the low-energy photons from the perspective of nonequilibrium statistical mechanics. We propose a mechanism of stochastic frequency-diffusion, the counterpart to stochastic acceleration for charged particles in a turbulent plasma, to modify the standard Kompaneets equation. The resulting violation of the Einstein relation allows to take advantage of low-frequency localization and finally leads to photon cooling. The new equation predicts a frequency distribution in agreement with the absolute temperature measurements of the cosmic background radiation down to about 20 MHz, for which we offer here an updated compilation. In that sense, the so called 'space roar' we observe today is interpreted as a nonequilibrium echo of the early universe, and of nonequilibrium conditions in the primordial plasma more specifically.
Volume
2
Issue
1
Uri
Url
Issn Identifier
2643-1564
Ads BibCode
2020PhRvR...2a3210B
Rights
open.access
File(s)
Loading...
Thumbnail Image
Name

PhysRevResearch.2.049001.pdf

Description
Erratum - auxiliary information
Size

244.96 KB

Format

Adobe PDF

Checksum (MD5)

a0b51e5876da6aea93c36e60b4ebe27f

Loading...
Thumbnail Image
Name

1908.08876_postprint_including_erratum.pdf

Description
postprint
Size

745.78 KB

Format

Adobe PDF

Checksum (MD5)

e5bd5c04df0786bfe1d93e882587ffdd