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Title: Large-amplitude modulation of periodic traveling waves

We introduce a new approach to the study of modulation of high-frequency periodic wave patterns, based on pseudodifferential analysis, multi-scale expansion, and Kreiss symmetrizer estimates like those in hyperbolic and hyperbolic-parabolic boundary-value theory. Key ingredients are local Floquet transformation as a preconditioner removing large derivatives in the normal direction of background rapidly oscillating fronts and the use of the periodic Evans function of Gardner to connect spectral information on component periodic waves to block structure of the resulting approximately constant-coefficient resolvent ODEs. Our main result is bounded-time existence and validity to all orders of large-amplitude smooth modulations of planar periodic solutions of multi-D reaction diffusion systems in the high-frequency/small wavelength limit.

 
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Award ID(s):
1700279
PAR ID:
10391310
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Discrete and Continuous Dynamical Systems - S
Volume:
15
Issue:
9
ISSN:
1937-1632
Page Range / eLocation ID:
2609
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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