On a Question of Craven and a Theorem of Belyi

dc.creatorBorisov, Alexandr
dc.date2002-05-25
dc.date2002-12-01
dc.date.accessioned2026-07-07T04:48:42Z
dc.date.available2026-07-07T04:48:42Z
dc.descriptionIn this elementary note we prove that a polynomial with rational coefficients divides the derivative of some polynomial which splits in $\Q$ if and only if all of its irrational roots are real and simple. This provides an answer to a question posed by Thomas Craven. Similar ideas also lead to a variation of the proof of Belyi's theorem that every algebraic curve defined over an algebraic number field admits a map to $P^1$ which is only ramified above three points. As it turned out, this variation was noticed previously by G. Belyi himself and Leonardo Zapponi.
dc.descriptionMain theorem was generalized to include reducible polynomials. To appear in Proceedings of AMS
dc.identifierhttps://arxiv.org/abs/math/0205266
dc.identifierhttp://arxiv.org/abs/math/0205266
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/64152
dc.subjectNumber Theory
dc.subject11R99
dc.titleOn a Question of Craven and a Theorem of Belyi
dc.typetext

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