Simons Collaboration on the Nonperturbative Bootstrap Annual Meeting 2019

Reductionism Vs. Bootstrap: Are Big Things Always Made of Elementary Things?
Slava Rychkov, Institut des Hautes Études Scientifiques

Participation is optional; separate registration is required.

Wednesday November 6, 2019
TEA: 4:15-5:00 pm
LECTURE 5:00-6:15 pm

Scientists love to reduce physical systems to a few elementary blocks, which they use like Lego building blocks to build more complicated ‘composite’ objects. Geoffrey Chew in the 1960s hypothesized, in connection with high-energy physics, a different type of situation. In this scenario, there are infinitely many particles, all of them equally elementary (or equally composite). The particles mutual existence is forced by tight requirements of self-consistency. He called this scheme ‘bootstrap,’ referring to a magical act of lifting oneself by one’s shoes.

In this lecture, Slava Rychkov will explain how the ‘bootstrap’ idea recently found a concrete realization in the theory of critical phenomena, with the three-dimensional Ising model being the simplest bootstrap system.

About the Speaker

Rychkov is a professor at the Institut des Hautes Etudes Scientifiques in Bures-sur-Yvette, France, and the École Normale Supérieure in Paris. He received his Ph.D. from Princeton University in 2002 followed by postdoctoral appointments at the University of Amsterdam and at the Scuola Normale Superiore in Pisa. He was a professor at the Université Pierre et Marie Curie in Paris from 2009 to 2012 and a staff member at the Theoretical Physics Department of CERN in Geneva from 2012 to 2018. Rychkov has been a recipient of the New Horizons in Physics Prize. His past work covers a wide range of subjects from pure mathematics to particle physics and string theory. His current main interest is developing efficient techniques for solving strongly coupled quantum field theories. He is the deputy director of the Simons Collaboration on the Nonperturbative Bootstrap.

More information is available here.

Chris Beem
Vertex algebras and superconformal field theories in four dimension

I will give an overview of developments in the chiral algebra approach to 4d N=2 SCFTs and discuss some key open questions.
Simon Caron-Huot
Analytic bootstrap and Lorentzian physics

Bootstrap methods analytically explain many general features of conformal field theories, such as how operators organize into families and how they behave at large quantum numbers. I will review some sharp estimates in this limit as well as new analytic results in holographic theories, all exploiting consistency in Lorentzian signature.
Tom Hartman
Bootstrapping black holes in two and three dimensions

I will describe recent progress on using the bootstrap to understand black holes in quantum gravity. This has connections to two classic problems: The sphere packing problem in Euclidean geometry, and the black hole information paradox.
Jared Kaplan
Universal features of quantum gravity from the bootstrap

We discuss universal features of quantum gravity that follow from conformal symmetry and the bootstrap. Virasoro symmetry provides a very powerful tool in 2+1-dimensions, but recent work has shown hints of a more general structure in higher dimensions, as well as causality constraints that limit the number of bulk degrees of freedom and point towards stringy physics in the UV.
Leonardo Rastelli
Overview of the Collaboration

I will give an overview of the Collaboration and of its activities in the first three years, emphasizing key ideas and results.
Slava Rychkov
CFT Osterwalder-Schrader theorem

Classic Osterwalder-Schrader theorem shows how a reflection-positive Euclidean QFT can be Wick-rotated to Minkowski signature. Unfortunately some of fine print conditions of this theorem are hard to check in applications. I will explain how these difficulties get resolved in the context of conformal field theories. If you were using boiling water to study elementary particles, you can keep doing this, and vice versa. (Joint work with Petr Kravchuk and Jiaxin Qiao)
David Simmons-Duffin
Developments in the numerical bootstrap

I will review recent developments in the numerical bootstrap, including new software tools and some new precise determinations of CFT data.
Balt van Rees
The S-matrix bootstrap

I will review techniques to explore and constrain the space of scattering amplitudes in non-conformal quantum field theories in various dimensions. The general constraints of analyticity, unitarity and crossing symmetry carve out a tight range of values for observables like three- and four-point couplings. Along the boundaries of the domains so obtained one can recover physically interesting amplitudes. We also discuss a setup based on QFT in AdS where the same constraints follow from an entirely different set of axioms, and comment on the relation between correlators and amplitudes.
Pedro Vieira
n-gons in N=4

I will quickly review how pentagons, hexagons and octagons arise as fundamental building blocks in the computation of open string amplitudes, closed micro-string amplitudes and closed macro-string amplitudes in AdS₅/CFT₄. I will then mention a few open problems as far as pentagons/hexagons and octagons go and comment on a few interesting open projects involving decagons and dodecagons.”
Xi Yin
Bootstrap meets Hamiltonian truncation: non-perturbative non-integrable S-matrices.

I will discuss the analytically continued S-matrix and resonances of the massive, non-integrable Ising field theory in two dimensions, using a combination of Hamiltonian truncation and bootstrap methods.