Table of Contents
Fetching ...

A remark on Gibbs measures with log-correlated Gaussian fields

Tadahiro Oh, Kihoon Seong, Leonardo Tolomeo

Abstract

We study Gibbs measures with log-correlated base Gaussian fields on the $d$-dimensional torus. In the defocusing case, the construction of such Gibbs measures follows from Nelson's argument. In this paper, we consider the focusing case with a quartic interaction. Using the variational formulation, we prove non-normalizability of the Gibbs measure. When $d = 2$, our argument provides an alternative proof of the non-normalizability result for the focusing $Φ^4_2$-measure by Brydges and Slade (1996). Furthermore, we provide a precise rate of divergence, where the constant is characterized by the optimal constant for a certain Bernstein's inequality on $\mathbb{R}^d$. We also go over the construction of the focusing Gibbs measure with a cubic interaction. In the appendices, we present (a) non-normalizability of the Gibbs measure for the two-dimensional Zakharov system and (b) the construction of focusing quartic Gibbs measures with smoother base Gaussian measures, showing a critical nature of the log-correlated Gibbs measure with a focusing quartic interaction.

A remark on Gibbs measures with log-correlated Gaussian fields

Abstract

We study Gibbs measures with log-correlated base Gaussian fields on the -dimensional torus. In the defocusing case, the construction of such Gibbs measures follows from Nelson's argument. In this paper, we consider the focusing case with a quartic interaction. Using the variational formulation, we prove non-normalizability of the Gibbs measure. When , our argument provides an alternative proof of the non-normalizability result for the focusing -measure by Brydges and Slade (1996). Furthermore, we provide a precise rate of divergence, where the constant is characterized by the optimal constant for a certain Bernstein's inequality on . We also go over the construction of the focusing Gibbs measure with a cubic interaction. In the appendices, we present (a) non-normalizability of the Gibbs measure for the two-dimensional Zakharov system and (b) the construction of focusing quartic Gibbs measures with smoother base Gaussian measures, showing a critical nature of the log-correlated Gibbs measure with a focusing quartic interaction.

Paper Structure

This paper contains 15 sections, 13 theorems, 214 equations.

Key Result

Theorem \oldthetheorem

Let $\lambda > 0$ and $k = 4$. Then, given any $K > 0$, we have where $R_N$ is the renormalized potential energy defined in Wick0 with $k = 4$. Moreover, the divergence rate of $Z_{K,N}$ is given by as $N\to \infty$. Here, $C_B$ is the optimal constant in Bernstein's inequality: where $P$ is the sharp Fourier projection onto the unit ball: and $\sigma_N$ is defined in sigma1. Moreover, we have

Theorems & Definitions (35)

  • Remark \oldthetheorem
  • Remark \oldthetheorem
  • Remark \oldthetheorem
  • Theorem \oldthetheorem
  • Remark \oldthetheorem
  • Remark \oldthetheorem
  • Remark \oldthetheorem
  • Remark \oldthetheorem
  • Theorem \oldthetheorem
  • Remark \oldthetheorem
  • ...and 25 more