Metamath Proof Explorer


Theorem isphtpy2d

Description: Deduction for membership in the class of path homotopies. (Contributed by Mario Carneiro, 23-Feb-2015)

Ref Expression
Hypotheses isphtpy.2 φ F II Cn J
isphtpy.3 φ G II Cn J
isphtpy2d.1 φ H II × t II Cn J
isphtpy2d.2 φ s 0 1 s H 0 = F s
isphtpy2d.3 φ s 0 1 s H 1 = G s
isphtpy2d.4 φ s 0 1 0 H s = F 0
isphtpy2d.5 φ s 0 1 1 H s = F 1
Assertion isphtpy2d φ H F PHtpy J G

Proof

Step Hyp Ref Expression
1 isphtpy.2 φ F II Cn J
2 isphtpy.3 φ G II Cn J
3 isphtpy2d.1 φ H II × t II Cn J
4 isphtpy2d.2 φ s 0 1 s H 0 = F s
5 isphtpy2d.3 φ s 0 1 s H 1 = G s
6 isphtpy2d.4 φ s 0 1 0 H s = F 0
7 isphtpy2d.5 φ s 0 1 1 H s = F 1
8 iitopon II TopOn 0 1
9 8 a1i φ II TopOn 0 1
10 9 1 2 3 4 5 ishtpyd φ H F II Htpy J G
11 1 2 10 6 7 isphtpyd φ H F PHtpy J G