Functional integrals for the Bogoliubov Gaussian measure: Exact asymptotic forms
V. R. Fatalov Lomonosov Moscow State University, Moscow, Russia
Abstract:
We prove theorems on the exact asymptotic forms as
$u\to\infty$ of two
functional integrals over the Bogoliubov measure
$\mu_{{\mathrm B}}$ of the forms
$$
\int_{C[0,\beta]}\biggl[\,\int_0^\beta
|x(t)|^p\,dt\biggr]^{u}\,d\mu_{{\mathrm B}}(x),\qquad
\int_{C[0,\beta]}\exp\biggl\{u\biggl(\,\int_0^\beta
|x(t)|^p\,dt\biggr)^{\!\alpha/p}\,\biggr\}\,d\mu_{{\mathrm B}}(x)
$$
for
$p=4,6,8,10$ with
$p>p_0$, where
$p_0=2+4\pi^2/\beta^2\omega^2$ is the threshold value,
$\beta$ is the inverse temperature,
$\omega$ is the eigenfrequency of the harmonic oscillator, and
$0<\alpha<2$. As the method
of study, we use the Laplace method in Hilbert functional spaces for
distributions of almost surely continuous Gaussian processes.
Keywords:
Bogoliubov measure, almost surely continuous Gaussian process, Laplace method in a functional Hilbert space, manifold of minimum values. Received: 24.05.2017
Revised: 24.08.2017
DOI:
10.4213/tmf9405