21 research outputs found
Index of elliptic operators for a diffeomorphism
We develop elliptic theory of operators associated with a diffeomorphism of a
closed smooth manifold. The aim of the present paper is to obtain an index
formula for such operators in terms of topological invariants of the manifold
and of the symbol of the operator. The symbol in this situation is an element
of a certain crossed product. We express the index as the pairing of the class
in K-theory defined by the symbol and the Todd class in periodic cyclic
cohomology of the crossed product.Comment: 37 page
Introduction to complex theory of differential equations
This book discusses the complex theory of differential equations or more precisely, the theory of differential equations on complex-analytic manifolds. Although the theory of differential equations on real manifolds is well known – it is described in thousands of papers and its usefulness requires no comments or explanations – to date specialists on differential equations have not focused on the complex theory of partial differential equations. However, as well as being remarkably beautiful, this theory can be used to solve a number of problems in real theory, for instance, the Poincaré balayage problem and the mother body problem in geophysics. The monograph does not require readers to be familiar with advanced notions in complex analysis, differential equations, or topology. With its numerous examples and exercises, it appeals to advanced undergraduate and graduate students, and also to researchers wanting to familiarize themselves with the subject
Asymptotic solutions to Fuchsian equations in several variables
The aim of this paper is to construct asymptotic solutions to multidimensional Fuchsian equations near points of their degeneracy. Such construction is based on the theory of resurgent functions of several complex variables worked out by the authors in [1]. This theory allows us to construct explicit resurgent solutions to Fuchsian equations and also to investigate evolution equations (Cauchy problems) with operators of Fuchsian type in their right-hand parts