A Variation on Leopoldt's Conjecture: Some Local Units instead of All Local Units

Abstract

Leopoldt's Conjecture is a statement about the relationship between the global and local units of a number field. Approximately the conjecture states that the Z_p-rank of the diagonal embedding of the global units into the product of all local units equals the Z-rank of the global units. The variation we consider asks: Can we say anything about the Z_p-rank of the diagonal embedding of the global units into the product of some local units? We use the p-adic Schanuel Conjecture to answer the question in the affirmative and moreover we give a value for the Z_p-rank (of the diagonal embedding of the global units into the product of some local units) in terms of the Z-rank of the global units and a property of the the local units included in the product.