The content analyzes an Ising spin glass model with a random symmetric couplings matrix J that is orthogonally invariant in law, and a deterministic external field h.
The key results are:
For sufficiently high temperature (small β), the authors prove that the first-order limit of the free energy is given by a replica-symmetric formula. This extends previous work that showed such a result in the absence of an external field.
The proof uses a conditional second moment method, where the authors condition on the iterates of an Approximate Message Passing (AMP) algorithm designed to solve the Thouless-Anderson-Palmer (TAP) mean-field equations for the model magnetization.
The specific AMP algorithm used has "memory-free" dynamics, which simplifies the state evolution analysis compared to alternative iterative procedures. This algorithm is related to Vector/Orthogonal AMP algorithms developed for compressed sensing.
Key technical ingredients include: (i) characterizing the asymptotic freeness of the AMP iterates with respect to the couplings matrix, (ii) evaluating certain exponential integrals over the orthogonal group using large deviations arguments, and (iii) analyzing variational problems that arise in the conditional moment computations.
The high-temperature assumption is crucial in establishing a global concavity property of these variational problems, which enables the authors to obtain tight upper and lower bounds.
To Another Language
from source content
arxiv.org
Key Insights Distilled From
by Zhou Fan,Yih... at arxiv.org 05-01-2024
https://arxiv.org/pdf/2105.02797.pdfDeeper Inquiries