首页 | 本学科首页   官方微博 | 高级检索  
     


Divisibility of class numbers of imaginary quadratic function fields by a fixed odd number
Authors:PRADIPTO BANERJEE  SRINIVAS KOTYADA
Affiliation:1. Indian Statistical Institute, Stat-Math Unit, 203 Barrackpore Trunk Road, Kolkata, 700 108, India
2. Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai, 600 113, India
Abstract:In this paper we find a new lower bound on the number of imaginary quadratic extensions of the function field $mathbb{F}_{q}(x)$ whose class groups have elements of a fixed odd order. More precisely, for q, a power of an odd prime, and g a fixed odd positive integer ≥?3, we show that for every ε?>?0, there are $gg q^{L(frac{1}{2}+frac{3}{2(g+1)}-epsilon)}$ polynomials $f in mathbb{F}_{q}[x]$ with $deg f=L$ , for which the class group of the quadratic extension $mathbb{F}_{q}(x, sqrt{f})$ has an element of order g. This sharpens the previous lower bound $q^{L(frac{1}{2}+frac{1}{g})}$ of Ram Murty. Our result is a function field analogue which is similar to a result of Soundararajan for number fields.
Keywords:
本文献已被 SpringerLink 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号