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)