Metamath Proof Explorer


Theorem tendo1ne0

Description: The identity (unity) is not equal to the zero trace-preserving endomorphism. (Contributed by NM, 8-Aug-2013)

Ref Expression
Hypotheses tendoid0.b ⊢ B = Base K
tendoid0.h ⊢ H = LHyp ⁡ K
tendoid0.t ⊢ T = LTrn ⁡ K ⁡ W
tendoid0.e ⊢ E = TEndo ⁡ K ⁡ W
tendoid0.o ⊢ O = f ∈ T ⟼ I ↾ B
Assertion tendo1ne0 ⊢ K ∈ HL ∧ W ∈ H → I ↾ T ≠ O

Proof

Step Hyp Ref Expression
1 tendoid0.b ⊢ B = Base K
2 tendoid0.h ⊢ H = LHyp ⁡ K
3 tendoid0.t ⊢ T = LTrn ⁡ K ⁡ W
4 tendoid0.e ⊢ E = TEndo ⁡ K ⁡ W
5 tendoid0.o ⊢ O = f ∈ T ⟼ I ↾ B
6 1 2 3 cdlemftr0 ⊢ K ∈ HL ∧ W ∈ H → ∃ g ∈ T g ≠ I ↾ B
7 simp3 ⊢ K ∈ HL ∧ W ∈ H ∧ g ∈ T ∧ g ≠ I ↾ B → g ≠ I ↾ B
8 fveq1 ⊢ I ↾ T = O → I ↾ T ⁡ g = O ⁡ g
9 8 adantl ⊢ K ∈ HL ∧ W ∈ H ∧ g ∈ T ∧ g ≠ I ↾ B ∧ I ↾ T = O → I ↾ T ⁡ g = O ⁡ g
10 simpl2 ⊢ K ∈ HL ∧ W ∈ H ∧ g ∈ T ∧ g ≠ I ↾ B ∧ I ↾ T = O → g ∈ T
11 fvresi ⊢ g ∈ T → I ↾ T ⁡ g = g
12 10 11 syl ⊢ K ∈ HL ∧ W ∈ H ∧ g ∈ T ∧ g ≠ I ↾ B ∧ I ↾ T = O → I ↾ T ⁡ g = g
13 5 1 tendo02 ⊢ g ∈ T → O ⁡ g = I ↾ B
14 10 13 syl ⊢ K ∈ HL ∧ W ∈ H ∧ g ∈ T ∧ g ≠ I ↾ B ∧ I ↾ T = O → O ⁡ g = I ↾ B
15 9 12 14 3eqtr3d ⊢ K ∈ HL ∧ W ∈ H ∧ g ∈ T ∧ g ≠ I ↾ B ∧ I ↾ T = O → g = I ↾ B
16 15 ex ⊢ K ∈ HL ∧ W ∈ H ∧ g ∈ T ∧ g ≠ I ↾ B → I ↾ T = O → g = I ↾ B
17 16 necon3d ⊢ K ∈ HL ∧ W ∈ H ∧ g ∈ T ∧ g ≠ I ↾ B → g ≠ I ↾ B → I ↾ T ≠ O
18 7 17 mpd ⊢ K ∈ HL ∧ W ∈ H ∧ g ∈ T ∧ g ≠ I ↾ B → I ↾ T ≠ O
19 18 rexlimdv3a ⊢ K ∈ HL ∧ W ∈ H → ∃ g ∈ T g ≠ I ↾ B → I ↾ T ≠ O
20 6 19 mpd ⊢ K ∈ HL ∧ W ∈ H → I ↾ T ≠ O