All Physics Faculty Publications
Document Type
Article
Journal/Book Title/Conference
Journal of Mathematical Physics
Volume
44
Issue
12
Publisher
American Institute of Physics
Publication Date
2003
First Page
6223
Last Page
6232
Abstract
Motivated by the partial differential equations of mixed type that arise in the reduction of the Einstein equations by a helical Killing vector field, we consider a boundary value problem for the helically-reduced wave equation with an arbitrary source in 2+1 dimensional Minkowski spacetime. The reduced equation is a second-order partial differential equation which is elliptic inside a disk and hyperbolic outside the disk. We show that the reduced equation can be cast into symmetric-positive form. Using results from the theory of symmetric-positive differential equations, we show that this form of the helically-reduced wave equation admits unique, strong solutions for a class of boundary conditions which include Sommerfeld conditions at the outer boundary.
Recommended Citation
C.G. Torre, “The helically-reduced wave equation as a symmetric-positive system,” Journal of Mathematical Physics, vol. 44, 2003, p. 6223.
http://arxiv.org/abs/math-ph/0309008
Comments
Originally published by the American Institute of Physics. Publisher's PDF can be accessed through the Journal of Mathematical Physics.