English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We discuss the possibility that dark matter axions form a Bose-Einsteincondensate (BEC) due to the gravitational self-interactions. The formation ofBEC occurs in the condensed regime, where the transition rate between differentmomentum states is large compared to the energy exchanged in the transition.The time evolution of the quantum state occupation number of axions in thecondensed regime is derived based on the in-in formalism. We recover theexpression for the thermalization rate due to self interaction of the axionfield, which was obtained in the other literature. It is also found that theleading order contributions for interactions between axions and other speciesvanish, which implies that the axion BEC does not give any significantmodifications on standard cosmological parameters.

Evolution and thermalization of dark matter axions in the condensed regime