Masses, host galaxies, and origins of supermassive black holes

Supermassive black holes (SMBHs) are ubiquitously found at the centers of massive galaxies near and far, and
likely played pivotal roles in shaping the evolution of their host galaxies. Yet, the origins of SMBHs remain a
mystery. Recent studies have made significant progress towards a coherent story of SMBH formation since
Cosmic Dawn. In this talk, I will discuss efforts to reliably measure the masses of distant active SMBHs with
light echoes, and to probe their co-evolution with host galaxies at high redshift. Then I will turn the spotlight to
the intriguing high-z population of “little red dots” recently unveiled by JWST, which may represent a
promising pathway to forging billion-solar-mass SMBHs in the early Universe. I will end with an advertisement
of the upcoming Roman eXtreme Deep Field public survey that reaches similar depths as the Hubble UDF/XDF
but with an area 140x larger.