{ "id": "1311.5846", "version": "v2", "published": "2013-11-22T19:22:23.000Z", "updated": "2013-12-04T16:22:59.000Z", "title": "Generic Newton polygons for curves of given p-rank", "authors": [ "Jeff Achter", "Rachel Pries" ], "comment": "16 pages, to appear in Algebraic Curves and Finite Fields: Codes, Cryptography, and other emergent applications, edited by H. Niederreiter, A. Ostafe, D. Panario, and A. Winterhof", "categories": [ "math.NT", "math.AG" ], "abstract": "We survey results and open questions about the $p$-ranks and Newton polygons of Jacobians of curves in positive characteristic $p$. We prove some geometric results about the $p$-rank stratification of the moduli space of (hyperelliptic) curves. For example, if $0 \\leq f \\leq g-1$, we prove that every component of the $p$-rank $f+1$ stratum of ${\\mathcal M}_g$ contains a component of the $p$-rank $f$ stratum in its closure. We prove that the $p$-rank $f$ stratum of $\\overline{\\mathcal M}_g$ is connected. For all primes $p$ and all $g \\geq 4$, we demonstrate the existence of a Jacobian of a smooth curve, defined over $\\overline{\\mathbb F}_p$, whose Newton polygon has slopes $\\{0, \\frac{1}{4}, \\frac{3}{4}, 1\\}$. We include partial results about the generic Newton polygons of curves of given genus $g$ and $p$-rank $f$.", "revisions": [ { "version": "v2", "updated": "2013-12-04T16:22:59.000Z" } ], "analyses": { "subjects": [ "11G20", "11M38", "14H10", "14H40", "14L05", "11G10" ], "keywords": [ "generic newton polygons", "open questions", "geometric results", "smooth curve", "survey results" ], "note": { "typesetting": "TeX", "pages": 16, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013arXiv1311.5846A" } } }