Eisenstein sum

From HandWiki

In mathematics, an Eisenstein sum is a finite sum depending on a finite field and related to a Gauss sum. Eisenstein sums were introduced by Eisenstein in 1848,[1] named "Eisenstein sums" by Stickelberger in 1890,[2] and rediscovered by Yamamoto in 1985,[3] who called them relative Gauss sums.

Definition

The Eisenstein sum is given by

[math]\displaystyle{ E(\chi,\alpha)=\sum_{Tr_{F/K}t=\alpha}\chi(t) }[/math]

where F is a finite extension of the finite field K, and χ is a character of the multiplicative group of F, and α is an element of K.[4]

References

  1. (Eisenstein 1848)
  2. (Stickelberger 1890)
  3. (Yamamoto 1985)
  4. (Lemmermeyer 2000)

Bibliography