Cyclotomic units in function fields
Sunghan Bae, Linsheng Yin · Proceedings of the American Mathematical Society · 2008
Let k k be a global function field over the finite field F q \mathbb {F}_{q} with a fixed place ∞ \infty of degree 1. Let K K be a cyclic extension of degree dividing q − 1 q-1 , in which ∞ \infty is totally ramified. For a certain abelian extension L L of k k containing K K , there are two notions of the group of cyclotomic units arising from sign normalized rank 1 Drinfeld modules on k k and on K K . In this article we compare these two groups of cyclotomic units.