THE DISCRIMINANT OF SUBFIELDS OF ℚ(ζ2r)
José Othon Dantas Lopes · Journal of Algebra and Its Applications · 2003
A formula for computing the discriminant of any number field K ⊂ ℚ(ζ2r), with r ≥ 3, is derived. The formula consists of two expressions, depending on whether K is cyclotomic or not. However, both expressions depend solely on m, the degree of K over ℚ, and they are derived from the Conductor-Discriminant Formula for Abelian extensions of ℚ.