Suppose KK is a number field, r=r1+r2−1r=r1+r2−1 (the rank of the unit group) and u1,dots,uru1,dots,ur are a basis of fundamental units. Suppose this basis minimizes the max over i=1,dots,ri=1,dots,r of the largest archimedean absolute value of uiui, and this value is M>0M>0. What is a good upper bound on MM in terms of standard invariants of the field KK? (In fact, I know one exists which for fixed degree is exponential in the regulator.)
More precisely, I'd like a bound on this minimax (min over choices of basis of max over basis elements) of the product of all archimedean absolute values which are greater than 11 (a.k.a. the "entropy") of the uiui. (This can of course be bounded by an r−1r−1st power of the previous bound.)
Is there a better bound/standard reference for bounding these quantities?
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