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