2023/07/05 by Caravenna, Francesco, Cottini, Francesca, Rossi, Maurizia · 5 citations
#35R60 #FOS: Mathematics #FOS: Physical sciences #Mathematical Physics (math-ph) #Primary: 82B44 #Probability (math.PR) #Secondary: 60F05
paper · doi:10.48550/arxiv.2307.02453
We study the 2d directed polymer in random environment in a novel *quasi-critical regime*, which interpolates between the much studied sub-critical and critical regimes. We prove Edwards-Wilkinson fluctuations throughout the quasi-critical regime, showing that the diffusively rescaled partition functions are asymptotically Gaussian. We deduce a corresponding result for the critical 2d Stochastic Heat Flow. A key challenge is the lack of hypercontractivity, which we overcome deriving new moment estimates.