In this paper, we study modular forms on two simply connected groups of type D4 over Q. One group, Gs, is a globally split group of type D4, viewed as the group of isotopies of the split rational octonions. The other, Gc, is the isotopy group of the rational (non-split) octonions. We study automorphic forms on Gs in analogy to the work of Gross, Gan, and Savin on G2; namely we study automorphic...

We survey the progress (or lack thereof!) that has been made on some questions about the p-adic slopes of modular forms that were raised by the first author in [Buz05], discuss strategies for making further progress, and examine other related questions.

In [DeFM], Deligne constructs l-adic parabolic cohomology groups attached to holomorphic cusp forms of weight ≥ 2 on congruence subgroups of SL2(Z). These groups occur in the l-adic cohomology of certain smooth projective varieties over Q—the Kuga-Sato varieties— which are suitably compactified families of products of elliptic curves. In view of Grothendieck’s conjectural theory of motives it i...

1. Basics 1 1.

These are the lecture notes of the lectures on Siegel modular forms at the Nordfjordeid Summer School on Modular Forms and their Applications. We give a survey of Siegel modular forms and explain the joint work with Carel Faber on vector-valued Siegel modular forms of genus 2 and present evidence for a conjecture of Harder on congruences between Siegel modular forms of genus 1 and 2.

Hecke’s theory is concerned with a family of finite-dimensional vector spaces Sk(N,χ), indexed by weights, levels, and characters. The Hecke operators on such spaces already provide a very rich theory. It will be very advantageous to pass to the adelic setting, however, for the same reasons that Hecke characters on number fields should be studied in the adelic setting (rather than as homomorphi...

1 SL2(Z) and elliptic curves 2 1.1 SL2(Z) and the moduli of complex tori . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.2 The Fundamental region and a system of generators . . . . . . . . . . . . . . . . . . . . . 3 1.3 The Weierstrass ℘ function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.4 Nonsingular cubics and the invariant j . . . . . . . . . . . ...

Motivation: it would be great if we could understand the p-adic variation of the Up-eigenvalues of modular forms as the weights and/or levels varied. (More generally, it would be really great if we could understand how the local p-adic Galois representations attached to automorphic forms behave – for example, even very weak “equidistribution” results here would presumably imply very strong auto...

‎We show that for all normalized Hecke eigenforms $f$‎ ‎with weight one and of CM type‎, ‎the number $(f,f)$ where $(cdot‎, ‎cdot )$ denotes‎ ‎the Petersson inner product‎, ‎is a linear form in logarithms and‎ ‎hence transcendental‎.