Publications Mathématiques de Besançon
Algèbre et Théorie des Nombres
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Mark Watkins
Jacobi sums and Grössencharacters
(Sommes de Jacobi et Grössencharacters)
Publications mathématiques de Besançon (2018), p. 111-122
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In 1952, Weil published a paper describing how to interpret Jacobi sums in terms of Hecke Grössencharacters of cyclotomic fields. We describe an explicit version of this, with reference to our previous work concerning algorithmic implementation of Grössencharacters. We correct various errors involving root numbers in the latter, and also indicate how Jacobi sum methods can be used to understand tame primes of hypergeometric motives.


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