Speaker: Eknath Ghate
Date: June 13, 2024
Affiliation: TIFR, Mumbai

Abstract: We shall explain the famous Herbrand-Ribet Theorem which connects sizes of certain class groups and divisibility properties of Bernoulli numbers. The proof uses classical modular forms in a natural way. If time permits, we shall also explain a vast generalization of the statement due to Wiles, which allowed him to deduce the Iwasawa main conjecture. This proof uses Hida's Lambda-adic forms.