{-# OPTIONS --safe --warning=error --without-K #-} open import LogicalFormulae open import Groups.Groups open import Groups.Definition open import Rings.Definition open import Rings.Lemmas open import Setoids.Setoids open import Rings.IntegralDomains.Definition open import Functions open import Sets.EquivalenceRelations open import Agda.Primitive using (Level; lzero; lsuc; _⊔_) module Fields.Fields where record Field {m n : _} {A : Set m} {S : Setoid {m} {n} A} {_+_ : A → A → A} {_*_ : A → A → A} (R : Ring S _+_ _*_) : Set (lsuc m ⊔ n) where open Ring R open Group additiveGroup open Setoid S field allInvertible : (a : A) → ((a ∼ Group.0G (Ring.additiveGroup R)) → False) → Sg A (λ t → t * a ∼ 1R) nontrivial : (0R ∼ 1R) → False 0F : A 0F = Ring.0R R record Field' {m n : _} : Set (lsuc m ⊔ lsuc n) where field A : Set m S : Setoid {m} {n} A _+_ : A → A → A _*_ : A → A → A R : Ring S _+_ _*_ isField : Field R encapsulateField : {m n : _} {A : Set m} {S : Setoid {m} {n} A} {_+_ : A → A → A} {_*_ : A → A → A} {R : Ring S _+_ _*_} (F : Field R) → Field' encapsulateField {A = A} {S = S} {_+_} {_*_} {R} F = record { A = A ; S = S ; _+_ = _+_ ; _*_ = _*_ ; R = R ; isField = F } {- record OrderedField {n} {A : Set n} {R : Ring A} (F : Field R) : Set (lsuc n) where open Field F field ord : TotalOrder A open TotalOrder ord open Ring R field productPos : {a b : A} → (0R < a) → (0R < b) → (0R < (a * b)) orderRespectsAddition : {a b c : A} → (a < b) → (a + c) < (b + c) -}