Quadratic pseudospectrum for identifying localized states
- URL: http://arxiv.org/abs/2204.10450v1
- Date: Fri, 22 Apr 2022 00:57:09 GMT
- Title: Quadratic pseudospectrum for identifying localized states
- Authors: Alexander Cerjan, Terry A. Loring, Fredy Vides
- Abstract summary: quadratic pseudospectrum is a method for approaching systems with incompatible observables.
We derive an important estimate relating the Clifford and quadratic pseudospectra.
We prove that the quadratic pseudospectrum is local, and derive bounds on the errors that are incurred by truncating the system in the vicinity of where the pseudospectrum is being calculated.
- Score: 68.8204255655161
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We examine the utility of the quadratic pseudospectrum in photonics and
condensed matter. Specifically, the quadratic pseudospectrum represents a
method for approaching systems with incompatible observables, as it both
minimizes the "eigen-error" in the joint approximate spectrum of the
incompatible observables and does not increase the system's computational
complexity. Moreover, we derive an important estimate relating the Clifford and
quadratic pseudospectra. Finally, we prove that the quadratic pseudospectrum is
local, and derive the bounds on the errors that are incurred by truncating the
system in the vicinity of where the pseudospectrum is being calculated.
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