Mod p Hecke Operators and Congruences Between Modular Forms.
Let and be an Eisenstein series and a cusp form, respectively, of the same weight and of the same level , both eigenfunctions of the Hecke operators, and both normalized so that . The main result we prove is that when and are congruent mod a prime (which we take in this paper to be a prime of lying over a rational prime ), the algebraic parts of the special values and satisfy congruences mod the same prime. More explicitly, we prove that, under certain conditions,where the...
In this short note we give a new approach to proving modularity of -adic Galois representations using a method of -adic approximations. This recovers some of the well-known results of Wiles and Taylor in many, but not all, cases. A feature of the new approach is that it works directly with the -adic Galois representation whose modularity is sought to be established. The three main ingredients are a Galois cohomology technique of Ramakrishna, a level raising result due to Ribet, Diamond, Taylor,...