{ "id": "2004.10189", "version": "v1", "published": "2020-04-21T17:52:57.000Z", "updated": "2020-04-21T17:52:57.000Z", "title": "Counting points on superelliptic curves in average polynomial time", "authors": [ "Andrew V. Sutherland" ], "comment": "15 pages", "categories": [ "math.NT", "math.AG" ], "abstract": "We describe the practical implementation of an average polynomial-time algorithm for counting points on superelliptic curves defined over $\\Q$ that is substantially faster than previous approaches. Our algorithm takes as input a superelliptic curves $y^m=f(x)$ with $m\\ge 2$ and $f\\in \\Z[x]$ any squarefree polynomial of degree $d\\ge 3$, along with a positive integer $N$. It can compute $\\#X(\\Fp)$ for all $p\\le N$ not dividing $m\\lc(f)\\disc(f)$ in time $O(md^3 N\\log^3 N\\log\\log N)$. It achieves this by computing the trace of the Cartier--Manin matrix of reductions of $X$. We can also compute the Cartier--Manin matrix itself, which determines the $p$-rank of the Jacobian of $X$ and the numerator of its zeta function modulo~$p$.", "revisions": [ { "version": "v1", "updated": "2020-04-21T17:52:57.000Z" } ], "analyses": { "subjects": [ "11G40", "14G10", "14H25", "11Y16" ], "keywords": [ "superelliptic curves", "average polynomial time", "counting points", "cartier-manin matrix", "average polynomial-time algorithm" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable" } } }