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The entropy of supersymmetric black holes in string theory compactifications can be related to that of a D- or M-brane system, which in many cases can be further reduced to a two-dimensional conformal field theory (2d CFT). For black holes in M-theory, this relation involves a decoupling limit where the black hole mass diverges. We suggest that moving away from this limit corresponds to a specific irrelevant perturbation of the 2d CFT, namely the supersymmetric completion of the Tar{T} deformation. We demonstrate that the black hole mass matches precisely with the Tar{T} deformed energy levels, upon identifying the Tar{T} deformation parameter with the inverse of the leading term of the black hole mass. We discuss various implications of this novel realization of the Tar{T} deformation, including a Hagedorn temperature for wrapped M5-branes, and potential change of degeneracies in the deformed theory.

Supermassive black holes are thought to be one of the fundamental ingredients in galaxy evolution, yet due to the difficulty of direct observation, basic questions such as the origin and growth of these black holes remain unanswered. A promising explanation for the origin of supermassive black holes is the direct collapse hypothesis, where massive gas clouds in the early universe contract to form supermassive stars which then collapse to black holes and become the seeds for observed supermassive black holes. This scenario is difficult to probe observationally because of the extreme distances involved, but one possibility is the general relativistic supernova of a supermassive star, an event which is luminous enough to be observed at high redshift. I will present numerical models of the evolution, instability and explosion of supermassive stars and discuss prospects for direct and indirect observation with current and future telescopes. I will then describe another recent paper where we attempt to elucidate correlations between active galactic nuclei and the morphology of the host galaxy using a variational autoencoder, a technique from generative modeling. We identify a correlation between host galaxy morphology and AGN activity and thus demonstrate the potential for similar techniques to be applied to larger datasets from future telescopes.

TBA

Fall date to be determined

Multi-messenger astrophysics has emerged as a rapidly growing field of research in the last decade, providing unique new insights into the properties of high-energy astrophysical sources. Such insights have been made possible by the complementary information carried by photons, cosmic rays, neutrinos, and gravitational waves about the astrophysical environments and processes in which they are produced. In this talk, I will review recent results in the search for the origin of high-energy neutrinos and ultra-high-energy cosmic rays and the possible role of active galactic nuclei, gamma-ray bursts, and tidal-disruption events as cosmic-ray accelerators based on the latest observations.