Alladi Ramakrishnan Hall

Dark Matter decay and cosmological Hubble measurement anomaly

Subinoy Das

IIA, Bengaluru

The Hubble tension between the ΛCDM-model-dependent prediction
of the current expansion rate H0 using Planck data and direct,
model-independent measurements in the local universe from the SH0ES
collaboration disagree at >3.5σ. Moreover, there exists a milder ∼2σ
tension between similar predictions for the amplitude S8 of matter
fluctuations and its measurement in the local universe. As explanations
relying on unresolved systematics have not been found, theorists have
been exploring explanations for these anomalies that modify the
cosmological model, altering early-universe-based predictions for these
parameters. However, new cosmological models that attempt to resolve one
tension often worsen the other. In this talk, I will investigate a
decaying dark matter (DDM) model as a solution to both tensions
simultaneously.