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Title: Topological obstructions to the diagonalisation of pseudodifferential systems
Given a matrix pseudodifferential operator on a smooth manifold, one may be interested in diagonalising it by choosing eigenvectors of its principal symbol in a smooth manner. We show that diagonalisation is not always possible, on the whole cotangent bundle or even in a single fibre. We identify global and local topological obstructions to diagonalisation and examine physically meaningful examples demonstrating that all possible scenarios can occur.  more » « less
Award ID(s):
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Proceedings of the American Mathematical Society, Series B
Page Range / eLocation ID:
472 to 486
Medium: X
Sponsoring Org:
National Science Foundation
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