APPLICATIONS OF THE STATIONARY PHASE FORMULA TO SOLUTIONS OF THE HELMHOLTZ EQUATION IN EXTERIOR DOMAINS.

Item

Title
APPLICATIONS OF THE STATIONARY PHASE FORMULA TO SOLUTIONS OF THE HELMHOLTZ EQUATION IN EXTERIOR DOMAINS.
Identifier
AAI8501168
identifier
8501168
Creator
RYWKIN, RICHARD J. F.
Contributor
Richard Sacksteder
Date
1984
Language
English
Publisher
City University of New York.
Subject
Mathematics
Abstract
In this paper we generalize the stationary phase formula to first provide any desired number of terms in the asymptotic expansion of integrals of the type (INT)(,(SUMM)) e('ik(phi)(y)) a(y)dy for large k and second to extend the stationary phase formula so as to treat integrals like the above which possess singularities in a(y) at isolated points, even in cases where (phi) is not differentiable at the singularity. Some lemmas are also presented which evaluate integrals of the type.;(DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI).;(derivable from the above) and give order of magnitude estimates for the remainder terms of the asymptotic expansion under certain assumptions on h where the interval (a,b) is either infinite or semi-infinite.;The generalized formula is then applied to two related integral operators which are used to determine solutions of the Helmholtz equation. As an example of the use of the method the case of 2-dimensional surfaces is examined in detail and the classical results are rederived.
Type
dissertation
Source
PQT Legacy CUNY.xlsx
degree
Ph.D.
Program
Mathematics
Item sets
CUNY Legacy ETDs