We address the Mach limit problem for the Euler equations in an exterior domain with an analytic boundary. We first prove the existence of tangential analytic vector fields for the exterior domain with constant analyticity radii and introduce an analytic norm in which we distinguish derivatives taken from different directions. Then we prove the uniform boundedness of the solutions in the analytic space on a time interval independent of the Mach number, and Mach limit holds in the analytic norm. The results extend more generally to Gevrey initial data with convergence in a Gevrey norm.
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Uniform bounds of families of analytic semigroups and Lyapunov Linear Stability of planar fronts
Abstract We study families of analytic semigroups, acting on a Banach space, and depending on a parameter, and give sufficient conditions for existence of uniform with respect to the parameter norm bounds using spectral properties of the respective semigroup generators. In particular, we use estimates of the resolvent operators of the generators along vertical segments to estimate the growth/decay rate of the norm for the family of analytic semigroups. These results are applied to prove the Lyapunov linear stability of planar traveling waves of systems of reaction–diffusion equations, and the bidomain equation, important in electrophysiology.
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- Award ID(s):
- 2106157
- PAR ID:
- 10553581
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Mathematische Nachrichten
- Volume:
- 297
- Issue:
- 7
- ISSN:
- 0025-584X
- Page Range / eLocation ID:
- 2750 to 2785
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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