BPHZ Renormalisation and Vanishing Subcriticality Limit of the Fractional Φ_d Model

Explore a lecture on BPHZ renormalisation and the vanishing subcriticality limit of the fractional Φ³_d model, presented by Nils Berglund at the Hausdorff Center for Mathematics. Delve into the study of stochastic PDEs on the d-dimensional torus with fractional Laplacian, quadratic nonlinearity, and space-time white noise. Examine the conditions for local subcriticality and the application of regularity structures theory. Investigate the precise asymptotics of renormalisation counterterms as the mollification parameter approaches zero and the fractional Laplacian parameter nears its critical value. Discover the behavior of counterterms in relation to the mollification parameter and gain insights into BPHZ renormalisation in a simplified context. Learn about the collaborative work with Yvain Bruned and its connection to recent developments in the field of stochastic PDEs and nonlinear fluctuations.