## High Energy Theory Events

#### Spring 2023

##### Causality Constraints on Gravitational Effective Theories

Speaker: Julio Parra-Martinez (California Institute of Technology)

In this talk I will describe constraints from causality and unitarity on 2→2 graviton scattering in weakly-coupled gravitational effective field theories. Together, causality and unitarity imply dispersion relations that connect low-energy observables to high-energy data. Using such dispersion relations, we can derive two-sided bounds on gravitational Wilson coefficients in terms of the [...]##### A Journey to the Center of the Field Space

Speaker: Max Wiesner (Harvard University)

In this talk I will explore the interior of the field spaces of four-dimensional effective theories of gravity. In the first part of the talk I will discuss the notion of a moduli-dependent species scale in N=2 theories serving as an effective UV cutoff in gravitational theories. I will show [...]##### Kaluza-Klein Spectrometry From Exceptional Field Theory

Speaker: Henning Samtleben (Ecole Normale Supérieure de Lyon)

I review new tools for the computation of Kaluza-Klein mass spectra associated with compactifications around various background geometries. Applications include the identification of non-supersymmetric AdS4 vacua which are perturbatively stable at all Kaluza-Klein levels.
February 10, 2023
2:00 pm – 3:00 pm (CDT)

##### Sharpening the Distance Conjecture in Diverse Dimensions

Speaker: Tom Rudelius (University of California, Berkeley)

The Distance Conjecture holds that any infinite-distance limit in the scalar field moduli space of a consistent theory of quantum gravity must be accompanied by a tower of light particles whose masses scale exponentially with proper field distance. While the evidence for this conjecture is formidable, there is at present no consensus on which values of of [...]##### How Single Particle States in 3+1d are Descendants in a (non-unitary) 2d CFT

Speaker: Noah Miller (Harvard University)

Following a recent collaboration with Cotler & Strominger, we present a basis of spin-0 single particle states in 3+1d Minkoski spacetime which transform as descendants in a 2d CFT with (negative) integer weight. At fixed weight, the states fill out a square matrix of states similar to the BFSS matrix [...]##### An Exceptional Approach to Kaluza-Klein Spectroscopy

Speaker: Oscar Varela (Universidad Autónoma de Madrid)

The spectrum of single-trace operators of holographic CFTs at strong coupling and large N can be mapped to the spectrum of Kaluza-Klein (KK) excitations over the dual AdS supergravity solutions. Unfortunately, computing these KK spectra is usually a prohibitively difficult task even for the simplest AdS solutions. In this talk, [...]##### Branes and Bundles Through Conifold Transitions and Heterotic Dualities

Speaker: James Gray (Virginia Tech)

I will discuss a novel proposal for transitioning the background geometry (including NS5-branes and holomorphic, slope-stable vector bundles) of 4-dimensional, N = 1 heterotic string compactifications through conifold transitions connecting Calabi-Yau threefolds. The proposal is geometric in nature and utilizes a description of how the cotangent bundles of the deformation [...]##### The Inner Workings of Exceptional Kaluza-Klein Spectroscopy

Speaker: Gabriel Larios (Texas A&M University)

Exceptional field theory provides a remarkably efficient way of obtaining information about the infinite towers of massive modes that arise in compactifications of string theory on spheres and hyperboloids. This includes AdS solutions of holographic interest with little or no preserved (super-)symmetry. In this talk we will give a detailed [...]##### Fundamental Membranes and the String Dilaton

Speaker: Hermann Nicolai (Max Planck Institute)

The quantization of the bosonic sector of supermembrane theory is considered in double dimensional reduction, in order to extract the dependence of the resulting world-sheet action on the string dilaton (which cannot be obtained from a purely kinematic reduction). The construction relies on a Polyakov-type approach with all six metric [...]