Several systems of differential operators are constructed and their study is commenced. These systems are generalizations, in a reasonable sense, of the Heisenberg Laplacian operators introduced by Folland and Stein. In particular, they admit large groups of conformal symmetries; various real form of the special linear groups, even special orthogonal groups, and the exceptional group of type E6...

Let $G$ be a group and $pi(G)$ be the set of primes $p$ such that $G$ contains an element of order $p$. Let $nse(G)$ be the set of the number of elements of the same order in $G$. In this paper, we prove that the simple group $L_2(p^2)$ is uniquely determined by $nse(L_2(p^2))$, where $pin{11,13}$‎.‎

All known direct constructions of designs over finite fields arise by subgroups of the normalizer of a Singer cycle, by lifted special linear groups, or lifted general linear groups. Other types of non-trivial automorphism groups for which designs over finite fields do exist have not been mentioned so far. In this paper we construct the first non-trivial designs over finite fields admitting the...