|Responsables :||Catherine Gille et Najib Idrissi|
|Email des responsables :|
|Adresse :||Sophie Germain|
|Orateur(s)||Antonio Lerario - Lyon 1,|
|Titre||Homology of intersections of real quadrics|
|Horaire||11:00 à 12:00|
|Résume||Intersections X of real quadrics are ubiquitous objects in geometry (to mention one example: every algebraic set is homeomorphic to an intersection of quadrics).
In this talk I will present a spectral sequence that efficiently computes the homology of X in terms of the arrangement, in the space of all quadratic forms, of those defining X.
The second term of this spectral sequence and its differential have a clear geometric interpretation - they are related to the Maslov cycle and the characteristic classes of the real grassmannian.
(joint work with A. Agrachev)