On the conjectural decomposition of symmetric powers of automorphic representations for GL(3) and GL(4)
arXiv:2105.14235
Abstract
Given a cuspidal automorphic representation for GL(3) over a number field and a positive integer , assume that the symmetric th power lifts of are isobaric automorphic for , cuspidal for , and that certain associated Rankin-Selberg products are isobaric automorphic. Then the number of cuspidal isobaric summands in the th symmetric power lift is bounded above by 3 when , and bounded above by 2 when with . We then investigate the analogous problem for GL(4).
18 pages. Comments welcome