We prove the existence, uniqueness, and regularity of minimizers of a polyconvex functional in two and three dimensions, which corresponds to theH1-projection of measure-preserving maps. Our result introduces a new criteria on the uniqueness of the minimizer, based on the smallness of the lagrange multiplier. No estimate on the second derivatives of the pressure is needed to get a unique global minimizer. As an application, we construct a minimizing movement scheme to constructLr-solutions of the Navier–Stokes equation (NSE) for a short time interval.
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Existence and regularity of minimizers for nonlocal energy functionals
In this paper, we consider minimizers for nonlocal energy functionals generalizing elastic energies that are connected with the theory of peridynamics [19] or nonlocal diffusion models [1]. We derive nonlocal versions of the Euler-Lagrange equations under two sets of growth assumptions for the integrand. Existence of minimizers is shown for integrands with joint convexity (in the function and nonlocal gradient components). By using the convolution structure, we show regularity of solutions for certain Euler-Lagrange equations. No growth assumptions are needed for the existence and regularity of minimizers results, in contrast with the classical theory.
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- Award ID(s):
- 1716790
- PAR ID:
- 10101514
- Date Published:
- Journal Name:
- Differential and integral equations
- Volume:
- 31
- Issue:
- 11/12
- ISSN:
- 0893-4983
- Page Range / eLocation ID:
- 807-832
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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