Abstract:
A $(2,3)$-generated group is a group that can be generated by an involution
and an element of order 3. These groups together with the trivial one and
two cyclic groups of orders 2 and 3 are exactly the quotients of the
modular group ${\rm PSL}(2,{\mathbb Z})$.
During past decades there was a considerable progress in determining which
finite simple groups are (2,3)-generated. Using probabilistic methods
Liebeck and Shalev showed that almost all finite classical groups of large
rank are (2,3)-generated. However, the full list of exceptions is still
unknown. Another (constructive) approach was developed by many authors.
Recently Pellegrini filled the last gaps for the series ${\rm PLS(n,q)}$ and
Tamburini and Pellegrini completed the unitary and symplectic cases.
Hurwitz groups (or finite (2,3,7)-generated groups) form an important
subclass of the (2,3)-generated groups. In general, the situation is quite
similar, i.e., most of the finite simple groups of large rank are Hurwitz,
but for small ranks we know less.
In my talk I will survey main results, open questions and methods used in
this area.