Seminario di fisica matematica
ore
11:30
presso Seminario II
In the late 70s, V. Rittenberg and D. Wyler introduced multi-graded (also
called color) algebras. These are generalizations of the notion of
superalgebra, in which the $\mathbb{Z}_2$-grading is replaced by
$\mathbb{Z}_2^n$-gradings, $n>1$, and the considered sign rule is modified
accordingly (i.e. is determined by the scalar product of the involved
$\mathbb{Z}_2^n$-degrees). The development of $\mathbb{Z}_2^n$-superalgebra
theory, and the corresponding geometry, recently acquired new relevance: V.
Ovsienko and S. Morier-Genoud observed that a remarkable class of classical
non-commutative algebras, namely quaternions and more generally Clifford
algebras, are in fact $\mathbb{Z}_2^n$-commutative for some $n$.
In this talk, I will report on joint works with N. Poncin and J. Grabowski,
concerning a first study of the notion of manifold in this multigraded
setting. Contrary to a widespread belief, this
$\mathbb{Z}_2^n$-supergeometry present important differences with the
classical supergeometry, and provides a sharpened viewpoint.