Transport bounds: from resistor networks to quantum chaos

APA

Lucas, A. (2017). Transport bounds: from resistor networks to quantum chaos. Perimeter Institute for Theoretical Physics. https://pirsa.org/17090049

MLA

Lucas, Andrew. Transport bounds: from resistor networks to quantum chaos. Perimeter Institute for Theoretical Physics, Sep. 25, 2017, https://pirsa.org/17090049

BibTex

          @misc{ scivideos_PIRSA:17090049,
            doi = {10.48660/17090049},
            url = {https://pirsa.org/17090049},
            author = {Lucas, Andrew},
            keywords = {Quantum Matter},
            language = {en},
            title = {Transport bounds: from resistor networks to quantum chaos},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2017},
            month = {sep},
            note = {PIRSA:17090049 see, \url{https://scivideos.org/pirsa/17090049}}
          }
          

Andrew Lucas University of Colorado Boulder

Source Repository PIRSA
Collection

Abstract

The Kovtun-Son-Starinets conjecture that the ratio of the viscosity to the entropy density was bounded from below by fundamental constants has inspired over a decade of conjectures about fundamental bounds on the hydrodynamic and transport coefficients of strongly interacting quantum systems.  I will present two complementary and (relatively) rigorous approaches to proving bounds on the transport coefficients of strongly interacting systems.   Firstly, I will discuss lower bounds on the conductivities (and thus, diffusion constants) of inhomogeneous fluids, based around the principle that transport minimizes the production of entropy.   I will show explicitly how to use this principle in classical theories, and in theories with a holographic dual. Secondly, I will derive lower bounds on sound velocities and diffusion constants arising from the consistency of hydrodynamics with quantum decoherence and chaos, in large N theories.   I will discuss the possible tension of such bounds with (some) holographic theories, and discuss resolutions to some existing puzzles.