Strongly r–matrix induced tensors, Koszul cohomology, and arbitrary–dimensional quadratic Poisson cohomology

We introduce the concept of strongly r-matrix induced (SRMI) Poisson structure, report on the relation of this property with the stabilizer dimension of the considered quadratic Poisson tensor, and classify the Poisson structures of the Dufour-Haraki classification (DHC) according to their membership of the family of SRMI tensors. One of the main results of our work is a generic cohomological procedure for SRMI Poisson structures in arbitrary dimension. This approach allows decomposing Poisson cohomology into, basically, a Koszul cohomology and a relative cohomology. Moreover, we investigate this associated Koszul cohomology, highlight its tight connections with Spectral Theory, and reduce the computation of this main building block of Poisson cohomology to a problem of linear algebra. We apply these upshots to two structures of the DHC and provide an exhaustive description of their cohomology. We thus complete our list of data obtained in previous works, see [MP06] and [AP07], and gain fairly good insight into the structure of Poisson cohomology. Key-words: r-matrix, quadratic Poisson structure, Lichnerowicz-Poisson cohomology, Koszul cohomology, relative cohomology, Spectral Theory MSC: 17B63, 17B56, 55N99