let P be non empty compact Subset of (TOP-REAL 2); :: thesis: ( P = { p where p is Point of (TOP-REAL 2) : |.p.| = 1 } implies ex f being Function of (Closed-Interval-TSpace (- 1),1),((TOP-REAL 2) | (Lower_Arc P)) st
( f is being_homeomorphism & ( for q being Point of (TOP-REAL 2) st q in Lower_Arc P holds
f . (q `1 ) = q ) & f . (- 1) = W-min P & f . 1 = E-max P ) )
assume A1:
P = { p where p is Point of (TOP-REAL 2) : |.p.| = 1 }
; :: thesis: ex f being Function of (Closed-Interval-TSpace (- 1),1),((TOP-REAL 2) | (Lower_Arc P)) st
( f is being_homeomorphism & ( for q being Point of (TOP-REAL 2) st q in Lower_Arc P holds
f . (q `1 ) = q ) & f . (- 1) = W-min P & f . 1 = E-max P )
then A2:
P is being_simple_closed_curve
by JGRAPH_3:36;
then A3:
Lower_Arc P is_an_arc_of E-max P, W-min P
by JORDAN6:def 9;
set P4 = Lower_Arc P;
A4:
( Lower_Arc P is_an_arc_of E-max P, W-min P & (Upper_Arc P) /\ (Lower_Arc P) = {(W-min P),(E-max P)} & (Upper_Arc P) \/ (Lower_Arc P) = P & (First_Point (Upper_Arc P),(W-min P),(E-max P),(Vertical_Line (((W-bound P) + (E-bound P)) / 2))) `2 > (Last_Point (Lower_Arc P),(E-max P),(W-min P),(Vertical_Line (((W-bound P) + (E-bound P)) / 2))) `2 )
by A2, JORDAN6:def 9;
reconsider g = proj1 as Function of (TOP-REAL 2),R^1 by TOPMETR:24;
set K0 = Lower_Arc P;
reconsider g2 = g | (Lower_Arc P) as Function of ((TOP-REAL 2) | (Lower_Arc P)),R^1 by PRE_TOPC:30;
A5:
for p being Point of ((TOP-REAL 2) | (Lower_Arc P)) holds g2 . p = proj1 . p
reconsider g3 = g2 as continuous Function of ((TOP-REAL 2) | (Lower_Arc P)),(Closed-Interval-TSpace (- 1),1) by A1, Lm4;
E-max P in {(W-min P),(E-max P)}
by TARSKI:def 2;
then A6:
E-max P in Lower_Arc P
by A4, XBOOLE_0:def 4;
W-min P in {(W-min P),(E-max P)}
by TARSKI:def 2;
then A7:
W-min P in Lower_Arc P
by A4, XBOOLE_0:def 4;
A8:
dom g3 = [#] ((TOP-REAL 2) | (Lower_Arc P))
by FUNCT_2:def 1;
then A9:
dom g3 = Lower_Arc P
by PRE_TOPC:def 10;
A10:
rng g3 = [#] (Closed-Interval-TSpace (- 1),1)
by A1, Lm4;
A11:
g3 is one-to-one
by A1, Lm4;
( not Lower_Arc P is empty & Lower_Arc P is compact )
by A3, JORDAN5A:1;
then A12:
(TOP-REAL 2) | (Lower_Arc P) is compact
;
Closed-Interval-TSpace (- 1),1 = TopSpaceMetr (Closed-Interval-MSpace (- 1),1)
by TOPMETR:def 8;
then
Closed-Interval-TSpace (- 1),1 is T_2
by PCOMPS_1:38;
then A13:
g3 /" is being_homeomorphism
by A8, A10, A11, A12, COMPTS_1:26, TOPS_2:70;
A14:
for q being Point of (TOP-REAL 2) st q in Lower_Arc P holds
(g3 /" ) . (q `1 ) = q
A17:
W-min P = |[(- 1),0 ]|
by A1, Th32;
A18: (g3 /" ) . (- 1) =
(g3 /" ) . (|[(- 1),0 ]| `1 )
by EUCLID:56
.=
W-min P
by A7, A14, A17
;
A19:
E-max P = |[1,0 ]|
by A1, Th33;
(g3 /" ) . 1 =
(g3 /" ) . (|[1,0 ]| `1 )
by EUCLID:56
.=
E-max P
by A6, A14, A19
;
hence
ex f being Function of (Closed-Interval-TSpace (- 1),1),((TOP-REAL 2) | (Lower_Arc P)) st
( f is being_homeomorphism & ( for q being Point of (TOP-REAL 2) st q in Lower_Arc P holds
f . (q `1 ) = q ) & f . (- 1) = W-min P & f . 1 = E-max P )
by A13, A14, A18; :: thesis: verum