Abstract:
We find the lower bound of the spectrum of the $q$-matrix for a
variety of mean-field models, as the number of interacting sites
goes to infinity. We also make a comparative study of the
asymptotic behavior of the lower bound and the spectral
gap and establish a characterization of a class of mean-field
models for which both bounds of the spectrum attain their extremal
values. The results are obtained with the help of the method suggested
by the second author in the late 1980s.
Keywords:mean-field models, birth-death processes, random walks on graphs, spectrum of the generator, maximal and minimal rates of exponential convergence, spectral gap.