Aidan Reill (SLAC) “Astrophysical Signals of Asymmetric Dark Matter “
Abstract: Our limited understanding of dark matter motivates exploring a wide range of masses and interaction strengths, independent of specific mediators or production mechanisms. Astrophysical systems, with their high energies and long lifetimes, provide unique laboratories for this pursuit. I will discuss two mechanisms by which dark matter can leave measurable imprints on astrophysical systems, even without annihilations. In the first, … Read More
Qiuyu Ren (UCB) “Khovanov skein lasagna modules of 4-manifolds, II”
Abstract: This is a continuation of the previous talk about skein lasagna modules. We review some features of the Khovanov homology and its Lee deformation. We examine the resulting skein lasagna modules with these two theories as inputs, extract a lasagna version of Rasmussen’s s-invariant, and state some formal properties. We then show that Khovanov/Lee skein lasagna modules and lasagna … Read More
Elba Alonso-Monsalve (MIT) “Phase space of JT gravity with positive cosmological constant”
Abstract: We construct the classical phase space of Jackiw-Teitelboim (JT) gravity with positive cosmological constant on spatial slices with circle topology. We identify solutions not previously discussed in the literature, and find the phase space has many singular points and is not even Hausdorff. Nonetheless, it admits a group-theoretic description which is quite amenable to quantization. We comment on next … Read More
Ian Sullivan (UC Davis) “Skein lasagna modules and Khovanov homology for $S^1 \times S^2$”
Abstract: Skein lasagna modules are invariants of smooth 4-dimensional manifolds capable of detecting exotic phenomena. Wall-type stabilization problems ask about the behavior of exotic phenomena under various topological operations. In this talk, we will describe the invariants we use and the necessary properties. We describe, with Wall-type external stabilization problems as motivation, a method for computing the Khovanov skein lasagna module of $S^2 … Read More
Martin Sasieta (UCB) “Baby Universes from Thermal Pure States in SYK”
Abstract: I will present a simple holographic model of closed universes originating from the black hole interior in JT gravity. The model relies on the insertion of a heavy operator to support the baby universe, together with a first-order phase transition between a black hole phase and an empty AdS phase. To this end, I will employ the Maldacena–Qi phase … Read More
Pankaj Munbodh (UCSC) “Lepton flavor violation at future colliders”
“Part I : Lepton flavor violating processes are highly suppressed in the Standard Model. Therefore, if observed, lepton flavor violation would be a clear indication of new physics beyond the Standard Model. We study the process $e^+e^-\to\tau\mu$ at tree-level in the Standard Model Effective Field Theory allowing for arbitrary $e^+e^-$ beam polarizations. The estimated sensitivities derived from the future circular … Read More
Bartek Czech (Institute for Advanced Study, Tsinghua University) ” A lesson from stabilizer states: Holography abhors syzygies
Abstract: Stabilizer states are a convenient and well-studied class of quantum states, with many applications including quantum error correction. One reason why they may NOT be good toy models of holographic systems is that they do not generally obey the constraints on entanglement entropies, which are implied by the Ryu-Takayanagi proposal. (Such constraints are collectively known as the holographic entropy … Read More
Ivan Burbano Aldana (UCB) “Real-time Estimators for Scattering Observables: A full account of finite-volume errors for quantum simulation”
Abstract: Lattice QCD is the only known systematically improvable tool we have for the determination of non-perturbative QCD observables from first principles. However, in its standard incarnation, the study of scattering observables beyond the three-particle energy threshold has been hindered by a number of challenges due to its Euclidean nature. In this talk I will give motivation for the lattice … Read More
Erwin Tanin (Stanford) “Cosmology of dark forces: strong limits and 𝜈 effects”
n the first three quarters of the talk, I will explain how cosmology sets the strongest constraints yet on long-range dark matter self-interactions at length scales shorter than 100 kpc. In the last quarter, hopefully, I will briefly discuss the early-universe dynamics of an ultralight scalar dark matter coupled to neutrinos, focusing on the dissipative backreaction of the neutrinos on … Read More
Tom Gannon (UC Riverside) “Coulomb branches and functoriality in the geometric Langlands program”
Abstract: In 2017, Braverman-Finkelberg-Nakajima gave a precise definition of the Coulomb branch of a 3d N = 4 supersymmetric gauge theory of cotangent type associated to a complex reductive group G and a finite dimensional complex representation N. In our first part of this talk, we will recall the definition and basic properties of such Coulomb branches, as well as … Read More