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Title: Using random walks to establish wavelike behavior in a linear FPUT system with random coefficients
We consider a linear Fermi-Pasta-Ulam-Tsingou lattice with random spatially varying material coefficients. Using the methods of stochastic homogenization we show that solutions with long wave initial data converge in an appropriate sense to solutions of a wave equation. The convergence is strong and both almost sure and in expectation, but the rate is quite slow. The technique combines energy estimates with powerful classical results about random walks, specifically the law of the iterated logarithm.  more » « less
Award ID(s):
2006172
PAR ID:
10353419
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:
2581
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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