"Quantum Link Models for the Quantum Simulation of Gauge Theories" - Uwe-Jens Wiese (AEC, Bern)

Thursday 23 Jul 2020, 11:00 → 12:00 Europe/Zurich

Vidyo only (CERN)

Quantum link models are a generalization of Wilson-type lattice gauge theories, in which exact continuous Abelian or non-Abelian gauge invariance is implemented on discrete quantum link degrees of freedom. Quantum links are generalized quantum spins that give rise to a finite-dimensional link Hilbert space. This makes them ideally suited for embodiment with cold matter, for example, with ultracold atoms in an optical lattice. The continuum limit of asymptotically free field theories is naturally reached via dimensional reduction when the discrete quantum degrees of freedom form collective massless exitations in the higher-dimensional theory. In this way, (1+1)-d CP(N-1) models arise from (2+1)-d SU(N) symmetric quantum spin systems in a broken
phase with massless Goldstone bosons and manifest U(N-1) symmetry. Similarly, (3+1)-d QCD emerges from a (4+1)-d Coulomb phase in which quantum links form massless gluons as collective excitations. Quarks are incorporated naturally as domain wall fermions. Both CP(N-1) models and non-Abelian gauge theories can be quantum simulated with ultracold alkaline-earth atoms in an optical lattice.

CERN2020new.pdf