Exactly solvable path integral for open cavities in terms of quasinormal modes

We evaluate the finite-temperature Euclidean phase-space path integral for the generating functional of a scalar field inside a leaky cavity. Provided the source is confined to the cavity, one can first of all integrate out the fields on the outside to obtain an effective action for the cavity alone. Subsequently, one uses an expansion of the cavity field in terms of its quasinormal modes (QNMs)-the exact, exponentially damped eigenstates of the classical evolution operator, which previously have been shown to be complete for a large class of models. Dissipation causes the effective cavity action to be nondiagonal in the QNM basis. The inversion of this action matrix inherent in the Gaussian path integral to obtain the generating functional is therefore nontrivial, but can be accomplished by invoking a novel QNM sum rule. The results are consistent with those obtained previously using canonical quantization.Comment: REVTeX, 26 pages, submitted to Phys. Rev.

Geographic variation in carotid revascularization among medicare beneficiaries, 2003-2006

10.1001/archinternmed.2010.194Archives of Internal Medicine170141218-1225AIMD

THE AMBITIONS OF POLICY DESIGN

There is no shortage of warnings concerning the hazards of excessive ambition in consciously-pursued public policy. In the light of these cautions, this paper considers the appropriate ambitions for policy design. The critics have missed the target. There is no need to fear ambition in policy design, provided that openness in communications about policy is secured. Copyright 1988 by The Policy Studies Organization.