Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-28T13:33:41.512Z Has data issue: false hasContentIssue false

A FUNCTIONAL RELATION FOR ACCESSORY PARAMETERS FOR GENUS 2 ALGEBRAIC CURVES WITH AN ORDER 4 AUTOMORPHISM

Published online by Cambridge University Press:  04 February 2005

ROBERT SILHOL
Affiliation:
Département de Mathématiques, UMR CNRS 5149, Université Montpellier II, Place E. Bataillon, 34095 Montpellier Cedex 5, [email protected]
Get access

Abstract

Let $C$ be a genus 2 algebraic curve defined by an equation of the form $y^2\,{=}\,x(x^2\,{-}\,1)(x\,{-} a)(x\,{-}\,1/a)$. As is well known, the five accessory parameters for such an equation can all be expressed in terms of $a$ and the accessory parameter $\frak b$ corresponding to $a$. The main result of the paper is that if $a'\,{=}\,\sqrt{1\,{-}\,{a}^2}$, which in general yields a non-isomorphic curve $C'$, then $\acb'a'({a'}^2\,{-}\,1) {=}\,{-}\frac38\,{-}\,\acb\,a\,({a}^2\,{-}\,1)$.

This is proven by it being shown how the uniformizing function from the unit disk to $C'$ can be explicitly described in terms of the uniformizing function for $C$.

Keywords

Type
Notes and Papers
Copyright
The London Mathematical Society 2005

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)