Jun 5 – 6, 2025
ETH Zurich
UTC timezone

Gravitational Redshift from Galaxy Clusters -- a Relativistic Approach

Jun 6, 2025, 9:30 AM
15m
Siemens Auditorium (HIT E 51) (ETH Zurich)

Siemens Auditorium (HIT E 51)

ETH Zurich

Wolfgang-Pauli-Strasse 27 HIT Building CH-8093 Zürich
Theory (no GW) Theory (no GW)

Speaker

Enea Di Dio (University of Geneva)

Description

Gravitational redshift is one of Einstein’s first predictions. On cosmological scales, we observe that the light emitted by Bright Central Galaxies at the bottom of a cluster’s gravitational potential is more redshifted than the average member galaxy. A first detection of this signal was made in 2011, but later studies questioned its interpretation, highlighting additional kinematic contributions. In this talk, I will present a fully relativistic derivation of these effects and compare it with previous studies. With a proper theoretical understanding, this effect provides a unique opportunity to test the equivalence principle at Mpc scales.

Author

Enea Di Dio (University of Geneva)

Co-authors

Camille Bonvin Sveva Castello (University of Geneva)

Presentation materials