Dual elliptic structures on CP2

We consider an almost complex structure J on CP2, or more generally an elliptic structure E which is tamed by the standard symplectic structure. An E-curve is a surface tangent to E (this generalizes the notion of J(holomorphic)-curve), and an E-line is an E-curve of degree 1. We prove that the space of E-lines is again a CP2 with a tame elliptic structure E^*, and that each E-curve has an associated dual E^*-curve. This implies that the E-curves, and in particular the J-curves, satisfy the Pl\"ucker formulas, which restricts their possible sets of singularities.Comment: 18 pages The only difference with the first version is the mention of the thesis of Benjamin MacKay ("Duality and integrable systems of pseudoholomorphic curves", Duke University, 1999), which I did not know at the time, and which contains a large part of the results of my pape

Bounds on primitives of differential forms and cofilling inequalities

We prove that on a Riemannian manifold, a smooth differential form has a primitive with a given (functional) upper bound provided the necessary weighted isoperimetric inequalities implied by Stokes are satisfied. We apply this to prove a comparison predicted by Gromov between the cofilling function and the filling area.Comment: The new features of the main result are its sharpness and the fact that the manifold is not assumed have bounded geometry, nor even to be complete. This paper corresponds to a part of a talk given in January 2004 in Haifa, at a workshop in memory of Robert Brooks. The other part, which is the "translation" in the framework of geometric group theory, will soon be deposited on arxi

Homological stability properties of spaces of rational J-holomorphic curves in P^2

In a well known work [Se], Graeme Segal proved that the space of holomorphic maps from a Riemann surface to a complex projective space is homology equivalent to the corresponding continuous mapping space through a range of dimensions increasing with degree. In this paper, we address if a similar result holds when other (not necessarily integrable) almost complex structures are put on projective space. We take almost complex structures that are compatible with the underlying symplectic structure. We obtain the following result: the inclusion of the space of based degree k J-holomorphic maps from P^1 to P^2 into the double loop space of P^2 is a homology surjection for dimensions j<3k-2. The proof involves constructing a gluing map analytically in a way similar to McDuff and Salamon in [MS] and Sikorav in [S] and then comparing it to a combinatorial gluing map studied by Cohen, Cohen, Mann, and Milgram in [CCMM].Comment: 28 page

On iterated translated points for contactomorphisms of R^{2n+1} and R^{2n} x S^1

A point q in a contact manifold is called a translated point for a contactomorphism \phi, with respect to some fixed contact form, if \phi (q) and q belong to the same Reeb orbit and the contact form is preserved at q. The problem of existence of translated points is related to the chord conjecture and to the problem of leafwise coisotropic intersections. In the case of a compactly supported contactomorphism of R^{2n+1} or R^{2n} x S^1 contact isotopic to the identity, existence of translated points follows immediately from Chekanov's theorem on critical points of quasi-functions and Bhupal's graph construction. In this article we prove that if \phi is positive then there are infinitely many non-trivial geometrically distinct iterated translated points, i.e. translated points of some iteration \phi^k. This result can be seen as a (partial) contact analogue of the result of Viterbo on existence of infinitely many iterated fixed points for compactly supported Hamiltonian symplectomorphisms of R^{2n}, and is obtained with generating functions techniques in the setting of arXiv:0901.3112.Comment: 10 pages, revised version. I removed the discussion on linear growth of iterated translated points, because it contained a mistake. To appear in the International Journal of Mathematic