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 investigate models that suggest that the vacuum energy decays into colddark matter (CDM) and into a homogeneous distribution of a thermalized cosmicmicrowave background (CMB), which is characteristic of an adiabatic vacuumenergy decay into photons. We show that the density fluctuation spectrumobtained from the CMB and galaxy distribution data agreement put strong limitson the rate of decay of the vacuum energy. A vacuum energy decaying into CDMincreases its total density \rho, diluting (\delta \rho/\rho)^2. The observedtemperature fluctuations of the CMB photons (\delta T/T)^2 are approximatelyproportional to CDM density fluctuations (\delta \rho/\rho)^2. In both case,when evaluating (\delta \rho/\rho)^2 at the recombination era, its presentmeasured value must be increased by a factor F. Since the (\delta \rho/\rho)^2derived from the CMB and galaxy distribution data agree to \sim 10%, themaximum value for F is F_{\rm max}\aprox 1.1. Our results indicate that therate of the decay of the vacuum energy into CDM and CMB photons are extremelysmall.Comment: to be published by Brazilian J. Physics Proceedings of 100 Years of  Relativity, International Conference on Classical and Quantum Aspects of  Gravity and Cosmology, Sao Paulo, August 22-24, 200

Strong limits on the possible decay of the vacuum energy into CDM or CMB photons