The representation growth of a group $G$ measures the asymptotic distribution of its irreducible representations.
Whenever the growth is polynomial, a suitable vehicle for studying it is a Dirichlet generating series called the representation zeta function of $G$.
One of the key invariants in this context is the abscissa of convergence of the representation
zeta function.
The spectrum of all abscissae arising across a given class of groups is of considerable
interest and has been studied in some cases.
In the realm of $p$-adic analytic groups (with perfect Lie algebra), the abscissae of convergence are explicitly known only for groups of small dimensions. But there are interesting asymptotic results for 'simple' $p$-adic analytic groups of increasing dimension.
In this talk, I will give an overview of the main tools and ingredients in this area and I will
report on recent work joint with Moritz Petschick to enlarge the class of groups.
Links:
[1] https://www.mpim-bonn.mpg.de/taxonomy/term/39
[2] https://www.mpim-bonn.mpg.de/node/3444
[3] https://www.mpim-bonn.mpg.de/node/246