Soit $F$ un corps local non archimédien, et $G$ le groupe des $F$-points d’un groupe réductif connexe quasi-déployé défini sur $F$. Dans cet article, on s’intéresse aux distributions sur $G$ invariantes par conjugaison, et à l’espace de leurs restrictions à l’algèbre de Hecke $\mathcal{H}$ des fonctions sur $G$ à support compact biinvariantes par un sous-groupe d’Iwahori $I$ donné. On montre tout d’abord que les valeurs d’une telle distribution sur $\mathcal{H}$ sont entièrement déterminées par sa restriction au sous-espace de dimension finie des éléments de $\mathcal{H}$ à support dans la réunion des sous-groupes parahoriques de $G$ contenant $I$. On utilise ensuite cette propriété pour montrer, moyennant certaines conditions sur $G$, que cet espace est engendré d’une part par certaines intégrales orbitales semi-simples, d’autre part par les intégrales orbitales unipotentes, en montrant tout d’abord des résultats analogues sur les groupes finis.

We compute some Hodge and Betti numbers of the moduli space of stable rank $r$, degree $d$ vector bundles on a smooth projective curve. We do not assume $r$ and $d$ are coprime. In the process we equip the cohomology of an arbitrary algebraic stack with a functorial mixed Hodge structure. This Hodge structure is computed in the case of the moduli stack of rank $r$, degree $d$ vector bundles on a curve. Our methods also yield a formula for the Poincaré polynomial of the moduli stack that is valid over any ground field. In the last section we use the previous sections to give a proof that the Tamagawa number of $\text{S}{{\text{L}}_{n}}$ is one.

Connections between behaviour of real analytic functions (with no negative Maclaurin series coefficients and radius of convergence one) on the open unit interval, and to a lesser extent on arcs of the unit circle, are explored, beginning with Karamata's approach. We develop conditions under which the asymptotics of the coefficients are related to the values of the function near 1; specifically, $a(n)\sim f(1-1/n)/\alpha n$ (for some positive constant $\alpha $), where $f\left( t \right)=\sum{a}\left( n \right){{t}^{n}}$. In particular, if $F=\sum{c\left( n \right){{t}^{n}}}$ where $c(n)\ge 0$ and $\Sigma c(n)=1$, then $f$ defined as ${{\left( 1-F \right)}^{-1}}$ (the renewal or Green's function for $F$) satisfies this condition if ${F}'$ does (and a minor additional condition is satisfied). In come cases, we can show that the absolute sum of the differences of consecutive Maclaurin coefficients converges. We also investigate situations in which less precise asymptotics are available.

The Casselman–Shalika method is a way to compute explicit formulas for periods of irreducible unramified representations of $p$-adic groups that are associated to unique models (i.e., multiplicity-free induced representations). We apply this method to the case of the Shalika model of $\text{G}{{\text{L}}_{n}}$, which is known to distinguish lifts from odd orthogonal groups. In the course of our proof, we further develop a variant of the method, that was introduced by Y.Hironaka, and in effect reduce many such problems to straightforward calculations on the group.