Metamath Proof Explorer


Theorem brric

Description: The relation "is isomorphic to" for (unital) rings. (Contributed by AV, 24-Dec-2019)

Ref Expression
Assertion brric ⊢ R ≃ 𝑟 S ↔ R RingIso S ≠ ∅

Proof

Step Hyp Ref Expression
1 df-ric ⊢ ≃ 𝑟 = RingIso -1 V ∖ 1 𝑜
2 rimfn ⊢ RingIso Fn V × V
3 1 2 brwitnlem ⊢ R ≃ 𝑟 S ↔ R RingIso S ≠ ∅