A Forty Year Journey
Abstract
I try to describe the stepwise progress in proving that massive black holes do exist in the Universe. As compared to forty years ago, measurements have pushed the 'size' of the 4 million solar mass concentration in the Galactic Center downward by almost 10^6, and its density up by 10^18. Looking ahead toward the future, the question is probably no longer whether SgrA* must be a MBH, but rather whether GR is correct on the scales of the event horizon, whether space-time is described by the Kerr metric and whether the 'no hair theorem' holds. Further improvements of the VLT interferometer GRAVITY (to GRAVITY+) and the next generation 25-40m telescopes (the ESO-ELT, the TMT and the GMT) promise further progress. A test of the no hair theorem in the Galactic Center might come from combining the stellar dynamics with EHT measurements of the photon ring of SgrA*.
Cite
@article{arxiv.2102.13000,
title = {A Forty Year Journey},
author = {Reinhard Genzel},
journal= {arXiv preprint arXiv:2102.13000},
year = {2021}
}
Comments
Nobel Lecture, December 8, 2020. 17 pages, 7 figures. Copyright: The Nobel Foundation