Agustin Moreno

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A basic question in symplectic topology is that of understanding which 2n‐dimensional smooth closed manifolds admit a symplectic structure. There are some obvious homotopical requirements, such as the existence of a cohomology 2‐class whose exterior wedge powers are all non‐zero (up to the maximal degree of the non‐zero cohomology groups) and of a non‐degenerate alternating 2‐form. In dimension 2n=4, Taubes '94 found some additional non‐trivial necessary conditions coming from the deep theory of Seiberg‐Witten invariants. This said, at this time it is still unknown whether there are some non‐trivial geometric conditions in the case of dimensions 2n>4.

The research visit of Agustin Moreno is in relation to a joint work of ours together with Lauran Toussaint and Francisco Presas, where we aim to prove that, given any smooth closed 4‐manifold M where all the homotopical necessary conditions to have a symplectic form are satisfied, its product MxT^2 with the 2‐torus T^2 admits a symplectic structure. In other words, up to stabilizing the 4‐manifold by taking a product with the 2‐torus, the non‐trivial geometric conditions of the 4‐dimensional case are no longer important.