module Algebra.fieldMorphisms where
open import Agda.Primitive using (Level; _⊔_; lsuc; lzero)
open import Types.relations
open import Types.equality
open import Types.functions2
open import Algebra.groups
open import Algebra.groups2
open import Algebra.groupMorphisms
open import Algebra.ringMorphisms
open import Algebra.fields
open import Algebra.fields2
We keep following the same pattern as we have been doing for groups and rings. A morphisms between two fields is a structure-preserving map in a way that preserves the field properties.
A field homomorphism between two fields 𝔸 and 𝔹 is a function
f : 𝔸 → 𝔹
such that ∀ x, y in 𝔸,
f
is congruent over +
, or \[f(x + y) = f(x) +
f(y)\]f
is congruent over ⋅
, or \[f( x ⋅ y) = f(x) ⋅
f(y)\]The fields are isomorphic if f
is bijective.