{ "id": "2006.07819", "version": "v1", "published": "2020-06-14T06:46:31.000Z", "updated": "2020-06-14T06:46:31.000Z", "title": "Sub-convexity bound for $GL(3) \\times GL(2)$ $L$-functions: $GL(3)$-spectral aspect", "authors": [ "Sumit Kumar", "Kummari Mallesham", "Saurabh Kumar Singh" ], "comment": "First draft", "categories": [ "math.NT" ], "abstract": "Let $\\phi$ be a Hecke-Maass cusp form for $SL(3, \\mathbb{Z})$ with Langlands parameters $({\\bf t}_{i})_{i=1}^{3}$ satisfying $$|{\\bf t}_{3} - {\\bf t}_{2}| \\leq T^{1-\\xi -\\epsilon}, \\quad \\, {\\bf t}_{i} \\approx T, \\quad \\, \\, i=1,2,3$$ with $1/2 < \\xi <1$ and any $\\epsilon>0$. Let $f$ be a holomorphic or Maass Hecke eigenform for $SL(2,\\mathbb{Z})$. In this article, we prove a sub-convexity bound $$L(\\phi \\times f, \\frac{1}{2}) \\ll \\max \\{ T^{\\frac{3}{2}-\\frac{\\xi}{4}+\\epsilon} , T^{\\frac{3}{2}-\\frac{1-2 \\xi}{4}+\\epsilon} \\} $$ for the central values $L(\\phi \\times f, \\frac{1}{2})$ of the Rankin-Selberg $L$-function of $\\phi$ and $f$, where the implied constants may depend on $f$ and $\\epsilon$. Conditionally, we also obtain a subconvexity bound for $L(\\phi \\times f, \\frac{1}{2})$ when the spectral parameters of $\\phi$ are in generic position, that is $${\\bf t}_{i} - {\\bf t}_{j} \\approx T, \\quad \\, \\text{for} \\, i \\neq j, \\quad \\, {\\bf t}_{i} \\approx T , \\, \\, i=1,2,3.$$", "revisions": [ { "version": "v1", "updated": "2020-06-14T06:46:31.000Z" } ], "analyses": { "keywords": [ "sub-convexity bound", "spectral aspect", "maass hecke eigenform", "hecke-maass cusp form", "generic position" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }