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The Group of Hamiltonian Homeomorphisms and C0-Symplectic Topology
Journal of Symplectic Geometry (2007)
  • Yong-Geun Oh, University of Wisconsin
  • Stefan Müller, Korea Institute for Advanced Study
The main purpose of this paper is to carry out some of the foundational study of C0-Hamiltonian geometry and C0-symplectic topology. We introduce the notions of the strong and the weak {\it Hamiltonian topology} on the space of Hamiltonian paths, and on the group of Hamiltonian diffeomorphisms. We then define the {\it group} Hameo(M,ω) and the space Hameow(M,ω) of {\it Hamiltonian homeomorphisms} such that Ham(M,ω)⊊Hameo(M,ω)⊂Hameow(M,ω)⊂Sympeo(M,ω) where Sympeo(M,ω) is the group of symplectic homeomorphisms. We prove that Hameo(M,ω) is a {\it normal subgroup} of Sympeo(M,ω) and contains all the time-one maps of Hamiltonian vector fields of C1,1-functions. We prove that Hameo(M,ω) is path connected and so contained in the identity component Sympeo0(M,ω) of Sympeo(M,ω). In the case of an orientable surface, we prove that the {\it mass flow} of any element from Hameo(M,ω) vanishes, which in turn implies that Hameo(M,ω) is strictly smaller than the identity component of the group of area preserving homeomorphisms when M≠S2. For the case of S2, we conjecture that Hameo(S2,ω) is still a proper subgroup of Homeoω0(S2)=Sympeo0(S2,ω).
  • Hamiltonian Homeomorphisms,
  • Homeomorphisms,
  • Mathematics
Publication Date
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Articles older than 5 years are open access. This article was retrieved from the Journal of Symplectic Geometry.
Citation Information
Yong-Geun Oh and Stefan Müller. "The Group of Hamiltonian Homeomorphisms and C0-Symplectic Topology" Journal of Symplectic Geometry Vol. 5 Iss. 2 (2007) p. 167 - 219 ISSN: 1527-5256
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