Event
William Witczak-Krempa, D茅pt. de physique, Universit茅 de Montr茅al
Tuesday, February 7, 2017 15:30
Room 4336, Pavillon Andr茅-Aisenstadt, 2920, Chemin de la tour, 5th floor, Montreal, QC, H3T 1J4, CA
Conformal field theories and quantum phase transitions: an entanglement perspective.
Quantum phase transitions occur when a quantum system undergoes a sharp change in its groundstate, e.g. between a ferro- and para-magnet. I will present a remarkable set of transitions, called quantum critical, that are described by conformal field theories (CFTs). I will focus on 2 and 3 spatial dimensions, where the conformal symmetry is powerful yet less constraining than in 1d. We will probe these scale-invariant theories via the structure of their quantum entanglement. The methods will include large-N expansions, the AdS/CFT duality from string theory, large-scale numerical simulations, and the bootstrap approach.