let T be non empty trivial TopSpace; for t being Point of T
for L being Loop of t holds the carrier of (pi_1 (T,t)) = {(Class ((EqRel (T,t)),L))}
let t be Point of T; for L being Loop of t holds the carrier of (pi_1 (T,t)) = {(Class ((EqRel (T,t)),L))}
set E = EqRel (T,t);
let L be Loop of t; the carrier of (pi_1 (T,t)) = {(Class ((EqRel (T,t)),L))}
thus
the carrier of (pi_1 (T,t)) c= {(Class ((EqRel (T,t)),L))}
XBOOLE_0:def 10 {(Class ((EqRel (T,t)),L))} c= the carrier of (pi_1 (T,t))proof
let x be
object ;
TARSKI:def 3 ( not x in the carrier of (pi_1 (T,t)) or x in {(Class ((EqRel (T,t)),L))} )
assume
x in the
carrier of
(pi_1 (T,t))
;
x in {(Class ((EqRel (T,t)),L))}
then consider P being
Loop of
t such that A1:
x = Class (
(EqRel (T,t)),
P)
by TOPALG_1:47;
P =
I[01] --> t
by TOPREALC:22
.=
L
by TOPREALC:22
;
hence
x in {(Class ((EqRel (T,t)),L))}
by A1, TARSKI:def 1;
verum
end;
let x be object ; TARSKI:def 3 ( not x in {(Class ((EqRel (T,t)),L))} or x in the carrier of (pi_1 (T,t)) )
assume
x in {(Class ((EqRel (T,t)),L))}
; x in the carrier of (pi_1 (T,t))
then A2:
x = Class ((EqRel (T,t)),L)
by TARSKI:def 1;
L in Loops t
by TOPALG_1:def 1;
then
x in Class (EqRel (T,t))
by A2, EQREL_1:def 3;
hence
x in the carrier of (pi_1 (T,t))
by TOPALG_1:def 5; verum