PIRSA:18090039

Entanglement Content of Particle Excitations

APA

Castro-Alvaredo, O. (2018). Entanglement Content of Particle Excitations. Perimeter Institute for Theoretical Physics. https://pirsa.org/18090039

MLA

Castro-Alvaredo, Olalla. Entanglement Content of Particle Excitations. Perimeter Institute for Theoretical Physics, Sep. 18, 2018, https://pirsa.org/18090039

BibTex

          @misc{ scivideos_PIRSA:18090039,
            doi = {10.48660/18090039},
            url = {https://pirsa.org/18090039},
            author = {Castro-Alvaredo, Olalla},
            keywords = {Quantum Fields and Strings},
            language = {en},
            title = {Entanglement Content of Particle Excitations},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2018},
            month = {sep},
            note = {PIRSA:18090039 see, \url{https://scivideos.org/pirsa/18090039}}
          }
          

Olalla Alvaredo City, University of London

Talk numberPIRSA:18090039
Source RepositoryPIRSA

Abstract

In this talk I will review the results of recent work in collaboration with  Cecilia De Fazio, Benjamin Doyon and István M. Szécsényi. We studied the entanglement of excited states consisting of a finite number of particle excitations. More precisely, we studied the difference between the entanglement entropy of such states and that of the ground state in a simple bi-partition of a quantum system, where both the size of the system and of the bi-partition are infinite, but their ratio is finite. We originally studied this problem in massive 1+1 dimensional QFTs where analytic computations were possible. We have found the results to apply more widely, including to higher dimensional free theories. In all cases we find that the increment of entanglement is a simple function of the ratio between region's and system's size only. Such function, turns out to be exactly the entanglement of a qubit state where the coefficients of the state are simply associated with the probabilities of particles being localised in one or the other part of the bi-partition. In this talk I will describe the results in some detail and discuss their domain of applicability. I will also highlight the main QFT techniques that we have used in order to obtain them analytically and  present some numerical data.