Description: A closed path in a simply connected space is contractible to a point. (Contributed by Mario Carneiro, 11-Feb-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | sconnpht | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | issconn | |
|
2 | fveq1 | |
|
3 | fveq1 | |
|
4 | 2 3 | eqeq12d | |
5 | id | |
|
6 | 2 | sneqd | |
7 | 6 | xpeq2d | |
8 | 5 7 | breq12d | |
9 | 4 8 | imbi12d | |
10 | 9 | rspccv | |
11 | 1 10 | simplbiim | |
12 | 11 | 3imp | |