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Weil group
Contents
Not to be confused with Weyl group .
Context
Group Theory
group theory
Classical groups
Finite groups
Group schemes
Topological groups
Lie groups
Super-Lie groups
Higher groups
Cohomology and Extensions
Related concepts
Arithmetic
number theory
number
natural number , integer number , rational number , real number , irrational number , complex number , quaternion , octonion , adic number , cardinal number , ordinal number , surreal number
arithmetic
arithmetic geometry , function field analogy
Arakelov geometry
Contents
Definition
Let F F be a p-adic field , with residue field denoted κ \kappa .
The Weil group W F W_F is the subgroup of the Galois group Gal ( F ¯ / F ) \mathrm{Gal}(\overline{F}/F) defined as the inverse image of Frobenius automorphisms Frob ℤ ⊂ Gal ( κ ¯ / κ ) \mathrm{Frob}^{\mathbb{Z}}\subset \mathrm{Gal}(\overline{\kappa}/\kappa) under the surjective map Gal ( F ¯ / F ) → Gal ( κ ¯ / κ ) \mathrm{Gal}(\overline{F}/F)\to\mathrm{Gal}(\overline{\kappa}/\kappa) .
References
John Tate , Section 1 in: Number theoretic background , in: Automorphic forms, representations and L-functions , Proc. Sympos. Pure Math., Oregon State Univ., Corvallis, Ore. (1977), Part 2, Proc. Sympos. Pure Math., XXXIII, pages 3–26. Amer. Math. Soc., Providence, RI (ISBN:978-0-8218-3371-1 , pdf , pdf )
See also:
Last revised on April 23, 2021 at 06:37:50.
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