Metamath Proof Explorer


Theorem phtpyhtpy

Description: A path homotopy is a homotopy. (Contributed by Mario Carneiro, 23-Feb-2015)

Ref Expression
Hypotheses isphtpy.2
|- ( ph -> F e. ( II Cn J ) )
isphtpy.3
|- ( ph -> G e. ( II Cn J ) )
Assertion phtpyhtpy
|- ( ph -> ( F ( PHtpy ` J ) G ) C_ ( F ( II Htpy J ) G ) )

Proof

Step Hyp Ref Expression
1 isphtpy.2
 |-  ( ph -> F e. ( II Cn J ) )
2 isphtpy.3
 |-  ( ph -> G e. ( II Cn J ) )
3 1 2 isphtpy
 |-  ( ph -> ( h e. ( F ( PHtpy ` J ) G ) <-> ( h e. ( F ( II Htpy J ) G ) /\ A. s e. ( 0 [,] 1 ) ( ( 0 h s ) = ( F ` 0 ) /\ ( 1 h s ) = ( F ` 1 ) ) ) ) )
4 simpl
 |-  ( ( h e. ( F ( II Htpy J ) G ) /\ A. s e. ( 0 [,] 1 ) ( ( 0 h s ) = ( F ` 0 ) /\ ( 1 h s ) = ( F ` 1 ) ) ) -> h e. ( F ( II Htpy J ) G ) )
5 3 4 syl6bi
 |-  ( ph -> ( h e. ( F ( PHtpy ` J ) G ) -> h e. ( F ( II Htpy J ) G ) ) )
6 5 ssrdv
 |-  ( ph -> ( F ( PHtpy ` J ) G ) C_ ( F ( II Htpy J ) G ) )