Dario Benedetti (École Polytechnique), Finite-size versus finite-temperature effects in the long-range O(N) model

Wednesday 13 Mar 2024, 11:00 → 12:30 Europe/Stockholm

Albano 3: 6228 - Mega (22 seats) (Albano Building 3)

Abstract:
Typical long-range models are field theories with a nonlocal kinetic 
term containing a fractional Laplacian. Although they might be 
considered exotic models from the point of view of high-energy physics, 
they actually have a long history in mathematical and statistical 
physics, and they have experimental realizations in condensed matter. 
After a brief review of their history, motivations and basic properties, 
I will present some recent results (arXiv:2311.04607) on finite-size and 
finite-temperature effects in the critical long-range O(N) model. In 
particular, the distinction between having a finite spatial size in the 
classical statistical model or being at finite temperature in the 
quantum model will play an important role: while in local (short-range) 
theories the two situations are technically similar, I will show that in 
long-range theories they are radically different, with the 
finite-temperature case being described by an anisotropic model, which 
we dubbed fractional Lifshitz model.