{ "id": "math/0103203", "version": "v2", "published": "2001-03-28T21:31:25.000Z", "updated": "2002-09-08T15:49:44.000Z", "title": "The endomorphism rings of jacobians of cyclic covers of the projective line", "authors": [ "Yuri G. Zarhin" ], "comment": "LaTeX2e, 14 pages. The paper will appear in Math. Proc. Cambridge Philos. Soc", "categories": [ "math.AG", "math.NT" ], "abstract": "Suppose K is a field of characteristic 0, $K_a$ is its algebraic closure, p is an odd prime. Suppose, $f(x) \\in K[x]$ is a polynomial of degree $n \\ge 5$ without multiple roots. Let us consider a curve $C: y^p=f(x)$ and its jacobian J(C). It is known that the ring End(J(C)) of all $K_a$-endomorphisms of J(C) contains the ring $Z[\\zeta_p]$ of integers in the pth cyclotomic field (generated by obvious automorphisms of C). We prove that $End(J(C))=Z[\\zeta_p]$ if the Galois group of f over K is either the symmetric group $S_n$ or the alternating group $A_n$.", "revisions": [ { "version": "v2", "updated": "2002-09-08T15:49:44.000Z" } ], "analyses": { "subjects": [ "14H40", "14K15", "14C25" ], "keywords": [ "cyclic covers", "endomorphism rings", "projective line", "pth cyclotomic field", "multiple roots" ], "note": { "typesetting": "LaTeX", "pages": 14, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2001math......3203Z" } } }