Henry Lin (Stanford) “Bootstrapping time-dependent Correlators”
In part I, I will review recent progress on bootstrapping matrix quantum mechanics. In part II of the talk, I will discuss upcoming work (with Cho, Gabai, Yeh, and Zheng) on generalizing the matrix bootstrap to rigorously bound time-dependent 2-point correlators. I will discuss both simple analytic bounds and numerics.
Zvi Bern (UCLA) “From Quantum Scattering Amplitudes to Gravitational Waves”
In this seminar, I will explain how modern ideas in quantum scattering amplitudes are being used to carry out high-precision calculations for gravitational wave emissions from binary black holes. This includes basic ideas from effective field theory, unitarity methods, the double-copy relations between gauge and gravity theories, and modern tools for Feynman loop integration.
Maciej Kolanowski (UCSB) “Ultralocal measure is not canonical”
Abstract: Starting from canonical quantization, one can derive the path integral formulation and show that the resulting measure differs from the standard ultralocal one. This difference becomes particularly significant in asymptotically AdS spacetimes, where it leads to a distinct functional space for fluctuations. We will argue that this canonical measure helps resolve several conceptual issues, including the choice of admissible boundary … Read More
Hong Zhe (Vincent) Chen (UCSB) “Observers seeing gravitational Hilbert spaces: abstract sources for an abstract path integral”
Abstract:——–The gravitational path integral suggests a striking result: the Hilbert space of closed universes in each superselection sector, a so-called alpha-sector, is one-dimensional. We develop an abstract formalism encapsulating recent proposals that modify the gravitational path integral in the presence of observers and allow larger Hilbert spaces to be associated with closed universes. Our formalism regards the gravitational path integral … Read More
LITP Mini-Workshop: Scott Collier (SYR) “Virasoro TQFT and the sum over topologies in 3d gravity”
Abstract: I will discuss the sum over topologies in three-dimensional quantum gravity and its relationship with the statistical interpretation of the boundary theory. I will put forward an axiomatization of the properties that a statistical CFT ensemble should possess. I will then identify a series of surgery moves on the gravity side that correspond to statistical contractions of OPE data in … Read More
LITP Mini-Workshop: Mukund Rangamani (UC Davis) “Comment on strings in AdS3”
Abstract: I will describe aspects of strings in AdS3 backgrounds supported by NS-NS flux. Specifically, I will explain how the one-loop analysis of the string partition function captures the physics of boundary currents, and comment on BPS observables. Time permitting, I will also discuss some subtle features of the tensionless limit which has been extensively explored in recent years.
LITP Mini-Workshop: Daniel Harlow (MIT)
Eunwoo Lee (TIFR) “Conformal Field Theory at Large Charge and Large Angular Momentum”
Abstract:In this talk, we study conformal field theories with a global U(1) symmetry on ℝ × S^{d−1} in the regime of large charge and large angular momentum. The lowest-energy state is a rotating superfluid vortex solution that interpolates between the large-charge superfluid at zero angular momentum and a Regge-limit state at large angular momentum. The stress tensor and U(1) current … Read More
Arvin Shahbazi-Moghaddam (Stanford) “The bulge quantum extremal surface in the gravity path integral.”
Abstract: A resolution of the black hole information problem requires a breakdown of isometricity in the bulk-to-boundary map. The degree of this non-isometricity is conjectured to be governed by the “bulge” quantum extremal surface lying inside the black hole interior, though a derivation of this has remained open. I will present recent progress toward such a derivation within the framework … Read More
Chris Akers (University of Colorado Boulder) “Effective theories for low complexity”
Abstract: Wilsonian effective theories are valid for low energy experiments. Semiclassical gravity, while an effective theory, seems different, requiring more than a low energy restriction: experiments also cannot be too complex. The formalism for such a low-complexity effective theory is much less understood. In this talk I’ll present progress closing this gap, developing models of novel low-complexity effective theories.