The linear stability of a steady state solution of 2D Euler equations of an
ideal fluid is being studied. We give an explicit geometric construction of
approximate eigenfunctions for the linearized Euler operator $L$ in vorticity
form acting on Sobolev spaces on two dimensional torus. We show that each
nonzero Lyapunov-Oseledets exponent for the flow induced by the steady state
contributes a vertical line to the essential spectrum of $L$. Also, we compute
the spectral and growth bounds for the group generated by $L$ via the maximal
Lyapunov-Oseledets exponent. When the flow has arbitrarily long orbits, we show
that the essential spectrum of $L$ on $L_2$ is the imaginary
@article{0306026,
author = {Shvydkoy, Roman and Latushkin, Yuri},
title = {Essential spectrum of the linearized 2D Euler equation and
Lyapunov-Oseledets exponents},
journal = {arXiv},
volume = {2003},
number = {0},
year = {2003},
language = {en},
url = {http://dml.mathdoc.fr/item/0306026}
}
Shvydkoy, Roman; Latushkin, Yuri. Essential spectrum of the linearized 2D Euler equation and
Lyapunov-Oseledets exponents. arXiv, Tome 2003 (2003) no. 0, . http://gdmltest.u-ga.fr/item/0306026/