Description: Module isomorphism is symmetric. (Contributed by Stefan O'Rear, 26-Feb-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | lmicsym | ⊢ ( 𝑅 ≃𝑚 𝑆 → 𝑆 ≃𝑚 𝑅 ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | brlmic | ⊢ ( 𝑅 ≃𝑚 𝑆 ↔ ( 𝑅 LMIso 𝑆 ) ≠ ∅ ) | |
2 | n0 | ⊢ ( ( 𝑅 LMIso 𝑆 ) ≠ ∅ ↔ ∃ 𝑓 𝑓 ∈ ( 𝑅 LMIso 𝑆 ) ) | |
3 | lmimcnv | ⊢ ( 𝑓 ∈ ( 𝑅 LMIso 𝑆 ) → ◡ 𝑓 ∈ ( 𝑆 LMIso 𝑅 ) ) | |
4 | brlmici | ⊢ ( ◡ 𝑓 ∈ ( 𝑆 LMIso 𝑅 ) → 𝑆 ≃𝑚 𝑅 ) | |
5 | 3 4 | syl | ⊢ ( 𝑓 ∈ ( 𝑅 LMIso 𝑆 ) → 𝑆 ≃𝑚 𝑅 ) |
6 | 5 | exlimiv | ⊢ ( ∃ 𝑓 𝑓 ∈ ( 𝑅 LMIso 𝑆 ) → 𝑆 ≃𝑚 𝑅 ) |
7 | 2 6 | sylbi | ⊢ ( ( 𝑅 LMIso 𝑆 ) ≠ ∅ → 𝑆 ≃𝑚 𝑅 ) |
8 | 1 7 | sylbi | ⊢ ( 𝑅 ≃𝑚 𝑆 → 𝑆 ≃𝑚 𝑅 ) |