Address.
Charles University, Faculty of Mathematics and Physics, Sokolovska 83,
186 75 Praha 8, Czech Republic
E-mail.
franp9am@artax.karlin.mff.cuni.cz
Abstract.
In this paper we study invariant differential operators on manifolds with a given parabolic structure. The
model for the parabolic geometry is the quotient of the orthogonal group by a maximal parabolic subgroup corresponding to crossing of the $k$-th simple root of the Dynkin diagram. In particular, invariant differential operators discussed in the paper correspond (in a flat model) to the Dirac operator in several variables.