Phase unwrapping and one-dimensional sign problems
Name
PhysRevD.98.074511.pdf
Size
5.75 MB
Format
Adobe PDF
Checksum (MD5)
c0bb8de2f41fbc9494588cf674feb20a
Author(s)
Detmold, William
Kanwar, Gurtej S.
Wagman, Michael L
Date Issued
October 2018
Journal
Physical Review D
Publisher
American Physical Society
Citation
Detmold, William, et al. “Phase Unwrapping and One-Dimensional Sign Problems.” Physical Review D, vol. 98, no. 7, Oct. 2018. © 2018 American Physical Society
Version
Final published version
Abstract
Sign problems in path integrals arise when different field configurations contribute with different signs or phases. Phase unwrapping describes a family of signal processing techniques in which phase differences between elements of a time series are integrated to construct noncompact unwrapped phase differences. By combining phase unwrapping with a cumulant expansion, path integrals with sign problems arising from phase fluctuations can be systematically approximated as linear combinations of path integrals without sign problems. This work explores phase unwrapping in zero-plus-one-dimensional complex scalar field theory. Results with improved signal-to-noise ratios for the spectrum of scalar field theory can be obtained from unwrapped phases, but the size of cumulant expansion truncation errors is found to be undesirably sensitive to the parameters of the phase unwrapping algorithm employed. It is argued that this numerical sensitivity arises from discretization artifacts that become large when phases fluctuate close to singularities of a complex logarithm in the definition of the unwrapped; phase.
MIT Department
Massachusetts Institute of Technology. Center for Theoretical Physics
Massachusetts Institute of Technology. Department of Physics
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Creative Commons Attribution
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1103/PhysRevD.98.074511
