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Verschiebung morphism

(under construction)

Idea

The Verschiebung morphism (German for ‘shift’) is an endomorphism, related to the Frobenius morphism.

Witt vectors

For a commutative ring AA, let 𝕎(A)\mathbb{W}(A) denote the set 1+TA[[T]]1+T A[[T]] of power series in AA with constant term one. Given a positive integer nn, the Verschiebung homomorphism is the additive homomorphism V n:𝕎(A)→𝕎(A)V_n : \mathbb{W}(A) \to \mathbb{W}(A) defined by the formula V n(f(T))=f(T n)V_n(f(T)) = f(T^n).

Created on June 25, 2015 at 04:46:26. See the history of this page for a list of all contributions to it.