Fisica statistica

Quantum dynamic cavity method

by Erik Aurell (KTH Royal Institute of Technology - Stockolm, Sweden)

Europe/Rome
Aula Careri (Dip. di Fisica - Edificio G. Marconi)

Aula Careri

Dip. di Fisica - Edificio G. Marconi

Description

A quantum system interacting with other quantum systems experiences these other systems as an effective environment, which can be represented by a Feynman-Vernon influence functional (IF) acting on system of interest. For networks having the topology of locally tree-like graphs, the Feynman-Vernon influence functional can be determined in a new quantum version of the cavity or Belief Propagation (BP) method. In the BP update stage, cavity IFs are mapped to cavity IFs, while in the BP output stage cavity IFs are combined to output IFs. Contrary to the classical case, in the quantum setting even uniform ferromagnetic interactions lead to non-trivial kernels and memory effects in the effective environment.  I will also discuss Replica Symmetry and the effects of disorder in the quantum cavity context.
 

Organised by

Federico Ricci Tersenghi