Title: Cosmology and UnificationAbstract: Precision measurements of primordial correlators in the CMB, Large Scale Structure, and 21-cm cosmology may contain “on-shell” imprints of extremely heavy particle physics, with masses at or even above the inflationary Hubble scale, via the remarkable inflationary mechanism(s) known as “cosmological collider physics”. I will describe new robust mechanisms for extending the energy-range and strength of such signals, … Read More
Title: S-matrix positivity without Lorentz invarianceAbstract: Positivity bounds on the S-matrix provide powerful constraints on effective field theories in flat space. Extending these results to cosmological backgrounds requires an understanding of the analytic structure of amplitudes in theories with broken Lorentz invariance. A paradigmatic example is provided by relativistic superfluids. We investigate the S-matrix in a UV complete model of relativistic superfluid: a complex scalar … Read More
https://lbnl.zoom.us/j/94928022788?pwd=emVQWG1mTnhSbHVqekVuenk0VEVQZz09 Title: Probing Dark Matter with Galactic Center White DwarfsAbstract: White dwarfs have long been considered as large-scale dark matter detectors. Owing to their high density and relatively large size, these objects can capture large amounts of dark matter, potentially producing detectable signals. In this talk, I will discuss new dark matter searches using the white dwarf population within the Milky Way’s … Read More
https://lbnl.zoom.us/j/94928022788?pwd=emVQWG1mTnhSbHVqekVuenk0VEVQZz09 Title: Building Dark Structure Before Big Bang NucleosynthesisAbstract: I present a novel mechanism for creating primordial black holes and MACHOs. A heavy dissipative dark sector can come to dominate the universe, creating an early matter dominated era prior to Big Bang Nucleosynthesis (BBN). At this time the dark matter can form halos which persist after the phase transition back to … Read More
https://lbnl.zoom.us/j/94928022788?pwd=emVQWG1mTnhSbHVqekVuenk0VEVQZz09
Title: Minimal Warm Inflation with the heavy QCD axion Abstract: Slow-roll inflation is a successful paradigm. However, even small couplings of the inflaton to other light fields can dramatically alter the dynamics and predictions of inflation. As an example, the inflaton can generically have an axion-like coupling to gauge bosons. Even relatively small couplings will automatically induce a thermal bath … Read More
https://lbnl.zoom.us/j/94928022788?pwd=emVQWG1mTnhSbHVqekVuenk0VEVQZz09
Title: Astrophysical Uncertainties in Dark Matter-Electron Scattering and How to Elude Them Abstract: In this talk, I will discuss how dark matter-electron scattering calculations depend on the underlying astrophysical model of the dark matter halo velocity distribution. I will give a brief review of the main astrophysical halo models and the measurements of their associated parameters. The predictions for dark … Read More
https://lbnl.zoom.us/j/94928022788?pwd=emVQWG1mTnhSbHVqekVuenk0VEVQZz09 Abstract: I will give an overview of the progress made in recent years in the study of CFT data for large charge operators using the semiclassical approximation. The basic result is that, in this regime, the data are universally codified by the dynamics of a superfluid phase for the theory compactified on the cylinder.The advances so far mostly concerned euclidean … Read More
https://lbnl.zoom.us/j/94928022788?pwd=emVQWG1mTnhSbHVqekVuenk0VEVQZz09 Title: The quality/cosmology tension for a post-inflationary QCD axion Abstract: It is difficult to construct a post-inflation QCD axion model that solves the axion quality problem (and hence the Strong CP problem) without introducing a cosmological disaster. In a post-inflation axion model, the axion field value is randomized during the Peccei-Quinn phase transition, and axion domain walls form at … Read More