Logarithmic singularity of the Szego kernel and a global invariant of strictly pseudoconvex domains
Logarithmic singularity of the Szego kernel and a global invariant of strictly pseudoconvex domains
复制标题
DOI:
10.4007/annals.2006.163.499
复制
发表时间:
2003-09
影响因子:
4.9
通讯作者:
K. Hirachi
中科院分区:
文献类型:
--
作者:
K. Hirachi
This paper is a continuation of Fefferman's program [7] for studying the geometry and analysis of strictly pseudoconvex domains. The key idea of the program is to consider the Bergman and Szeg? kernels of the domains as analogs of the heat kernel of Riemannian manifolds. In Riemannian (or confor mai) geometry, the coefficients of the asymptotic expansion of the heat kernel can be expressed in terms of the curvature of the metric; by integrating the co efficients one obtains index theorems in various settings. For the Bergman and Szeg? kernels, there has been much progress made on the description of their asymptotic expansions based on invariant theory ([7], [1], [15]); we now seek for invariants that arise from the integral of the coefficients of the expansions. We here prove that the integral of the coefficient of the logarithmic sin gularity of the Szeg? kernel gives a biholomorphic invariant of a domain ft, or a CR invariant of the boundary dft, and moreover that the invariant is un changed under perturbations of the domain (Theorem 1). We also show that the same invariant appears as the coefficient of the logarithmic term of the volume expansion of the domain with respect to the Bergman volume element (Theorem 2). This second result is an analogue of the derivation of a conformai invariant from the volume expansion of conformally compact Einstein mani folds which arises in the AdS/CFT correspondence ? see [10] for a discussion and references. The proofs of these results are based on Kashiwara's microlocal analysis of the Bergman kernel in [17], where he showed that the reproducing prop erty of the Bergman kernel on holomorphic functions can be "quantized" to a reproducing property of the microdifferential operators (i.e., classical ana lytic pseudodifferential operators). This provides a system of microdifferential equations that characterizes the singularity of the Bergman kernel (which can be formulated as a microfunction) up to a constant multiple; such an argument