Institute for Advanced Study Informal Astrophysics Seminar - Title & Abstract Updated

State-of-the-art local and primordial measurements of the Hubble constant (H0) are currently in tension at the 4.4 sigma level. New physics and systematic errors have been invoked as potential explanations. I will discuss two new, independent techniques for measuring H0 from time-domain astronomy that can help distinguish between these and other scenarios. The first is to use time delays from strongly gravitationally lensed supernovae to constrain H0 geometrically. The second is to construct a distance-redshift relation using electromagnetic counterparts to gravitational wave events. I will describe experimental efforts that are currently underway to carry out both of these measurements, namely the Zwicky Transient Facility lensed supernova search and the Dark Energy Camera neutron star merger follow-up program.