{ "id": "1712.08912", "version": "v1", "published": "2017-12-24T12:20:18.000Z", "updated": "2017-12-24T12:20:18.000Z", "title": "Spatial Hamiltonian identities for nonlocally coupled systems", "authors": [ "Berry Bakker", "Arnd Scheel" ], "comment": "38 pages, 1 figure", "categories": [ "math.DS", "math.AP" ], "abstract": "We consider a broad class of systems of nonlinear integro-differential equations posed on the real line that arise as Euler-Lagrange equations to energies involving nonlinear nonlocal interactions. Although these equations are not readily cast as dynamical systems, we develop a calculus that yields a natural Hamiltonian formalism. In particular, we formulate Noether's theorem in this context, identify a degenerate symplectic structure, and derive Hamiltonian differential equations on finite-dimensional center manifolds when those exist. Our formalism yields new natural conserved quantities. For Euler-Lagrange equations arising as traveling-wave equations in gradient flows, we identify Lyapunov functions. We provide several applications to pattern-forming systems including neural field and phase separation problems.", "revisions": [ { "version": "v1", "updated": "2017-12-24T12:20:18.000Z" } ], "analyses": { "subjects": [ "35S30", "45G15", "35C07", "37K05", "37L10", "37L45" ], "keywords": [ "spatial hamiltonian identities", "nonlocally coupled systems", "euler-lagrange equations", "natural hamiltonian formalism", "nonlinear integro-differential equations" ], "note": { "typesetting": "TeX", "pages": 38, "language": "en", "license": "arXiv", "status": "editable" } } }