2020/10/26 by Lee, Jungin
#11F06 #11H06 #11R04 #11R21 #FOS: Mathematics #Number Theory (math.NT)
paper · doi:10.48550/arxiv.2010.13489
In this paper we improve the upper bound of the number NK, n(X) of degree n extensions of a number field K with absolute discriminant bounded by X. This is achieved by giving a short OK-basis of an order of an extension L of K. Our result generalizes the best known upper bound on Nℚ, n(X) by Lemke Oliver and Thorne to all number fields K. Precisely, we prove that NK, n(X) ≪K, n Xc (log n)2 for an explicit constant c independent on K and n. We also improve the upper bound of the number of maximal arithmetic subgroups in certain connected semisimple Lie groups.