MPIfR/AIfA Main Colloquium, Speaker: Prof. Dr. Tessa Baker

/MPIfR/AIfA Main Colloquium, Speaker: Prof. Dr. Tessa Baker

MPIfR/AIfA Main Colloquium, Speaker: Prof. Dr. Tessa Baker

Event Details

Max Planck Institute for Radio Astronomy/Argelander Institute for Astronomy Main Colloquium

Titel: Cosmology with Gravitational Wave Sirens

Speaker: Prof. Dr. Tessa Baker, University of Portsmouth

The first eight years of direct gravitational wave detection have had a huge impact not only on astrophysics, but also on cosmology and fundamental physics. Central to these developments have been Sirens, gravitational wave sources for which we can measure both distances and redshifts. The most spectacular kind of sirens are multimessenger events like the binary neutron star merger GW170817, with both gravitational wave and electromagnetic counterparts. However, these represent only a tiny fraction of all gravitational wave events. So are all the other gravitational wave events useless, from a cosmology perspective? In this talk I’ll introduce the alternative Dark Sirens method, which enables us to extract cosmology from regular, non-counterpart gravitational wave events. I’ll explain how this technique can be used to obtain an independent measurement of the Hubble constant, and also to test the laws of gravity operating on the largest scales. I’ll describe some subtleties that require careful handling, (hopefully!) convince you that we can overcome them, and show the latest results obtained from gravitational wave detections to date.