Langlands Base Change for GL(2)
arXiv:0912.2080
Abstract
Let F be a totally real Galois number field. We prove the existence of base change relative to the extension F/Q for every classical newform of odd level, under simple local assumptions on the field F.
27 pages. Main result improved: now there is no condition on the primes in the level of the newform (they are allowed to ramify in F)