English

The Floer homotopy type of the cotangent bundle

Algebraic Topology 2007-08-31 v2 Symplectic Geometry

Abstract

Let M be a closed, oriented, n-dimensional manifold. In this paper we describe a spectrum in the sense of homotopy theory, Z(T^*M), whose homology is naturally isomorphic to the Floer homology of the cotangent bundle, T^*M. This Floer homology is taken with respect to a Hamiltonian H: S^1 x T^*M --> R, which is quadratic near infinity. Z(T^*M) is constructed assuming a basic smooth gluing result of J-holomorphic cylinders. This spectrum will have a C.W decomposition with one cell for every periodic solution of the equation defined by the Hamiltonian vector field X_H. Its induced cellular chain complex is exactly the Floer complex. The attaching maps in the C.W structure of Z(T^*M) are described in terms of the framed cobordism types of the moduli spaces of J -holomorphic cylinders in T^*M with given boundary conditions. This is done via a Pontrjagin-Thom construction, and an important ingredient in this is proving, modulo this gluing result, that these moduli spaces are compact, smooth, framed manifolds with corners. We then prove that Z(T^*M), which we refer to as the "Floer homotopy type" of T^*M, has the same homotopy type as the suspension spectrum of the free loop space, LM. This generalizes the theorem first proved by C. Viterbo that the Floer homology of T^*M is isomorphic to H_*(LM).

Keywords

Cite

@article{arxiv.math/0702852,
  title  = {The Floer homotopy type of the cotangent bundle},
  author = {Ralph L. Cohen},
  journal= {arXiv preprint arXiv:math/0702852},
  year   = {2007}
}

Comments

36 pages. A gluing assumption is described, and a more complete discussion of framing issues is given

R2 v1 2026-07-22T17:51:53.609Z