{ "id": "0707.1708", "version": "v1", "published": "2007-07-11T21:08:53.000Z", "updated": "2007-07-11T21:08:53.000Z", "title": "On certain period relations for cusp forms on GL_n", "authors": [ "A. Raghuram", "Freydoon Shahidi" ], "comment": "40 pages. This preprint is also up on preprint server of the Erwin Schrodinger Institute as preprint number 1928. The URL is http://www.esi.ac.at/Preprint-shadows/esi1928.html", "categories": [ "math.NT", "math.RT" ], "abstract": "Let $\\pi$ be a regular algebraic cuspidal automorphic representation of ${\\rm GL}_n({\\mathbb A}_F)$ for a number field $F$. We consider certain periods attached to $\\pi$. These periods were originally defined by Harder when $n=2$, and later by Mahnkopf when $F = {\\mathbb Q}$. In the first part of the paper we analyze the behaviour of these periods upon twisting $\\pi$ by algebraic Hecke characters. In the latter part of the paper we consider Shimura's periods associated to a modular form. If $\\phi_{\\chi}$ is the cusp form associated to a character $\\chi$ of a quadratic extension, then we relate the periods of $\\phi_{\\chi^n}$ to those of $\\phi_{\\chi}$, and as a consequence give another proof of Deligne's conjecture on the critical values of symmetric power $L$-functions associated to dihedral modular forms. Finally, we make some remarks on the symmetric fourth power $L$-functions.", "revisions": [ { "version": "v1", "updated": "2007-07-11T21:08:53.000Z" } ], "analyses": { "subjects": [ "11F67", "11F70", "22E55" ], "keywords": [ "cusp form", "period relations", "regular algebraic cuspidal automorphic representation", "algebraic hecke characters", "symmetric fourth power" ], "note": { "typesetting": "TeX", "pages": 40, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2007arXiv0707.1708R" } } }