R201, Astronomy-Mathematics Building, NTU
(台灣大學天文數學館 201室)
Title of 1st talk: Excursions with modular symbols and cup products
Title of 2nd talk : Reciprocity maps with restricted ramification
Romyar T. Sharifi (University of Arizona)
Title of 1st talk: Excursions with modular symbols and cup products
Abstract:
I will provide some background on a conjecture of mine relating modular symbols in the homology of modular curves and cup products of cyclotomic units in the cohomology of integer rings. I hope to describe some finer aspects of work on the conjecture and its direct refinements as well.
Title of 2nd talk : Reciprocity maps with restricted ramification
Abstract:
I will discuss work that I began long ago to compare various "reciprocity maps" in the cohomology of number fields with restricted ramification. I will describe a couple of applications, in particular to the structure of Selmer groups of residual representations of families of cuspidal eigenforms congruent to Eisenstein series.