PIRSA:10050074

From few to many

APA

Fendley, P. (2010). From few to many. Perimeter Institute for Theoretical Physics. https://pirsa.org/10050074

MLA

Fendley, Paul. From few to many. Perimeter Institute for Theoretical Physics, May. 27, 2010, https://pirsa.org/10050074

BibTex

          @misc{ scivideos_PIRSA:10050074,
            doi = {10.48660/10050074},
            url = {https://pirsa.org/10050074},
            author = {Fendley, Paul},
            keywords = {},
            language = {en},
            title = {From few to many},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2010},
            month = {may},
            note = {PIRSA:10050074 see, \url{https://scivideos.org/pirsa/10050074}}
          }
          

Paul Fendley University of Oxford

Talk numberPIRSA:10050074
Source RepositoryPIRSA
Talk Type Conference

Abstract

I discuss a class of systems with a very special property: exact results for physical quantities can be found in the many-body limit in terms of the original (bare) parameters in the Hamiltonian. A classic result of this type is Onsager and Yang's formula for the magnetization in the Ising model. I show how analogous results occur in a fermion chain with strong interactions, closely related to the XXZ spin chain. This is done by exploiting a supersymmetry, and noting that certain quantites are independent of finite-size effects. I also discuss how these ideas are related to an interacting generalization of the Kitaev honeycomb model.