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/

Zendy Plus

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

Zendy Tools

Zendy Open

The semiclassical approximation has frequently been used to describe theinitial stage of particle production, often called preheating, which occursafter the inflationary epoch in chaotic models of inflation. During this phasebackreaction effects from the produced particles on the inflaton field aresignificant, and one might be concerned about the validity of the semiclassicalapproximation, even though large backreaction effects are allowed if theinflaton field is coupled to a large number of quantum fields. A criterion ispresented for the validity of the semiclassical approximation in this case andthe question of whether this criterion is satisfied during preheating isaddressed.

Validity of the semiclassical approximation during the preheating phase of chaotic inflation