let T be non empty TopSpace; for s being Real
for FS2 being Functional_Sequence of [: the carrier of T, the carrier of T:],REAL st ( for n being Nat ex pmet being Function of [: the carrier of T, the carrier of T:],REAL st
( FS2 . n = pmet & pmet is_a_pseudometric_of the carrier of T & ( for pq being Element of [: the carrier of T, the carrier of T:] holds pmet . pq <= s ) & ( for pmet9 being RealMap of [:T,T:] st pmet = pmet9 holds
pmet9 is continuous ) ) ) holds
for pmet being Function of [: the carrier of T, the carrier of T:],REAL st ( for pq being Element of [: the carrier of T, the carrier of T:] holds pmet . pq = Sum (((1 / 2) GeoSeq) (#) (FS2 # pq)) ) holds
( pmet is_a_pseudometric_of the carrier of T & ( for pmet9 being RealMap of [:T,T:] st pmet = pmet9 holds
pmet9 is continuous ) )
set Geo = (1 / 2) GeoSeq ;
set cT = the carrier of T;
set cTT = the carrier of [:T,T:];
let s be Real; for FS2 being Functional_Sequence of [: the carrier of T, the carrier of T:],REAL st ( for n being Nat ex pmet being Function of [: the carrier of T, the carrier of T:],REAL st
( FS2 . n = pmet & pmet is_a_pseudometric_of the carrier of T & ( for pq being Element of [: the carrier of T, the carrier of T:] holds pmet . pq <= s ) & ( for pmet9 being RealMap of [:T,T:] st pmet = pmet9 holds
pmet9 is continuous ) ) ) holds
for pmet being Function of [: the carrier of T, the carrier of T:],REAL st ( for pq being Element of [: the carrier of T, the carrier of T:] holds pmet . pq = Sum (((1 / 2) GeoSeq) (#) (FS2 # pq)) ) holds
( pmet is_a_pseudometric_of the carrier of T & ( for pmet9 being RealMap of [:T,T:] st pmet = pmet9 holds
pmet9 is continuous ) )
let FS2 be Functional_Sequence of [: the carrier of T, the carrier of T:],REAL; ( ( for n being Nat ex pmet being Function of [: the carrier of T, the carrier of T:],REAL st
( FS2 . n = pmet & pmet is_a_pseudometric_of the carrier of T & ( for pq being Element of [: the carrier of T, the carrier of T:] holds pmet . pq <= s ) & ( for pmet9 being RealMap of [:T,T:] st pmet = pmet9 holds
pmet9 is continuous ) ) ) implies for pmet being Function of [: the carrier of T, the carrier of T:],REAL st ( for pq being Element of [: the carrier of T, the carrier of T:] holds pmet . pq = Sum (((1 / 2) GeoSeq) (#) (FS2 # pq)) ) holds
( pmet is_a_pseudometric_of the carrier of T & ( for pmet9 being RealMap of [:T,T:] st pmet = pmet9 holds
pmet9 is continuous ) ) )
assume A1:
for n being Nat ex pmet being Function of [: the carrier of T, the carrier of T:],REAL st
( FS2 . n = pmet & pmet is_a_pseudometric_of the carrier of T & ( for pq being Element of [: the carrier of T, the carrier of T:] holds pmet . pq <= s ) & ( for pmet9 being RealMap of [:T,T:] st pmet = pmet9 holds
pmet9 is continuous ) )
; for pmet being Function of [: the carrier of T, the carrier of T:],REAL st ( for pq being Element of [: the carrier of T, the carrier of T:] holds pmet . pq = Sum (((1 / 2) GeoSeq) (#) (FS2 # pq)) ) holds
( pmet is_a_pseudometric_of the carrier of T & ( for pmet9 being RealMap of [:T,T:] st pmet = pmet9 holds
pmet9 is continuous ) )
set SGeo = s (#) ((1 / 2) GeoSeq);
deffunc H1( Nat) -> Element of bool [:[: the carrier of T, the carrier of T:],REAL:] = (((1 / 2) GeoSeq) . $1) (#) (FS2 . $1);
consider GeoF being Functional_Sequence of [: the carrier of T, the carrier of T:],REAL such that
A2:
for n being Nat holds GeoF . n = H1(n)
from SEQFUNC:sch 1();
the carrier of [:T,T:] = [: the carrier of T, the carrier of T:]
by BORSUK_1:def 2;
then reconsider GeoF9 = GeoF as Functional_Sequence of the carrier of [:T,T:],REAL ;
A3:
for pq being Element of [: the carrier of T, the carrier of T:]
for k being Nat holds
( 0 <= (GeoF # pq) . k & (GeoF # pq) . k <= (s (#) ((1 / 2) GeoSeq)) . k )
proof
let pq be
Element of
[: the carrier of T, the carrier of T:];
for k being Nat holds
( 0 <= (GeoF # pq) . k & (GeoF # pq) . k <= (s (#) ((1 / 2) GeoSeq)) . k )let k be
Nat;
( 0 <= (GeoF # pq) . k & (GeoF # pq) . k <= (s (#) ((1 / 2) GeoSeq)) . k )
consider x,
y being
object such that A4:
(
x in the
carrier of
T &
y in the
carrier of
T )
and A5:
[x,y] = pq
by ZFMISC_1:def 2;
reconsider x =
x,
y =
y as
Point of
T by A4;
consider pmet1 being
Function of
[: the carrier of T, the carrier of T:],
REAL such that A6:
FS2 . k = pmet1
and A7:
pmet1 is_a_pseudometric_of the
carrier of
T
and A8:
for
pq being
Element of
[: the carrier of T, the carrier of T:] holds
pmet1 . pq <= s
and
for
pmet19 being
RealMap of
[:T,T:] st
pmet1 = pmet19 holds
pmet19 is
continuous
by A1;
A9:
0 <= pmet1 . (
x,
y)
by A7, NAGATA_1:29;
dom ((((1 / 2) GeoSeq) . k) (#) (FS2 . k)) = [: the carrier of T, the carrier of T:]
by A6, FUNCT_2:def 1;
then A10:
(((1 / 2) GeoSeq) . k) * ((FS2 . k) . pq) =
((((1 / 2) GeoSeq) . k) (#) (FS2 . k)) . pq
by VALUED_1:def 5
.=
(GeoF . k) . pq
by A2
.=
(GeoF # pq) . k
by SEQFUNC:def 10
;
(1 / 2) |^ k > 0
by NEWTON:83;
then A11:
((1 / 2) GeoSeq) . k > 0
by PREPOWER:def 1;
then
(((1 / 2) GeoSeq) . k) * (pmet1 . pq) <= (((1 / 2) GeoSeq) . k) * s
by A8, XREAL_1:64;
hence
(
0 <= (GeoF # pq) . k &
(GeoF # pq) . k <= (s (#) ((1 / 2) GeoSeq)) . k )
by A6, A5, A10, A9, A11, SEQ_1:9;
verum
end;
A12:
for n being Nat ex f being RealMap of [:T,T:] st
( GeoF9 . n = f & f is continuous & ( for pq9 being Point of [:T,T:] holds f . pq9 >= 0 ) )
proof
let n be
Nat;
ex f being RealMap of [:T,T:] st
( GeoF9 . n = f & f is continuous & ( for pq9 being Point of [:T,T:] holds f . pq9 >= 0 ) )
consider pmet1 being
Function of
[: the carrier of T, the carrier of T:],
REAL such that A13:
FS2 . n = pmet1
and
pmet1 is_a_pseudometric_of the
carrier of
T
and
for
pq being
Element of
[: the carrier of T, the carrier of T:] holds
pmet1 . pq <= s
and A14:
for
pmet19 being
RealMap of
[:T,T:] st
pmet1 = pmet19 holds
pmet19 is
continuous
by A1;
the
carrier of
[:T,T:] = [: the carrier of T, the carrier of T:]
by BORSUK_1:def 2;
then reconsider pmet19 =
pmet1 as
RealMap of
[:T,T:] ;
reconsider pR =
pmet19 as
Function of
[:T,T:],
R^1 by TOPMETR:17;
pmet19 is
continuous
by A14;
then
pR is
continuous
by JORDAN5A:27;
then consider fR being
Function of
[:T,T:],
R^1 such that A15:
for
pq9 being
Point of
[:T,T:] for
rn being
Real st
pR . pq9 = rn holds
fR . pq9 = (((1 / 2) GeoSeq) . n) * rn
and A16:
fR is
continuous
by JGRAPH_2:23;
reconsider f =
fR as
RealMap of
[:T,T:] by TOPMETR:17;
A17:
dom f = the
carrier of
[:T,T:]
by FUNCT_2:def 1;
take
f
;
( GeoF9 . n = f & f is continuous & ( for pq9 being Point of [:T,T:] holds f . pq9 >= 0 ) )
A18:
dom pmet1 = [: the carrier of T, the carrier of T:]
by FUNCT_2:def 1;
A19:
GeoF9 . n = (((1 / 2) GeoSeq) . n) (#) (FS2 . n)
by A2;
then A20:
dom (FS2 . n) = dom (GeoF9 . n)
by VALUED_1:def 5;
A21:
[: the carrier of T, the carrier of T:] = the
carrier of
[:T,T:]
by BORSUK_1:def 2;
hence
(
GeoF9 . n = f &
f is
continuous & ( for
pq9 being
Point of
[:T,T:] holds
f . pq9 >= 0 ) )
by A13, A16, A20, A18, A17, A21, A22, JORDAN5A:27, PARTFUN1:5;
verum
end;
let pmet be Function of [: the carrier of T, the carrier of T:],REAL; ( ( for pq being Element of [: the carrier of T, the carrier of T:] holds pmet . pq = Sum (((1 / 2) GeoSeq) (#) (FS2 # pq)) ) implies ( pmet is_a_pseudometric_of the carrier of T & ( for pmet9 being RealMap of [:T,T:] st pmet = pmet9 holds
pmet9 is continuous ) ) )
assume A23:
for pq being Element of [: the carrier of T, the carrier of T:] holds pmet . pq = Sum (((1 / 2) GeoSeq) (#) (FS2 # pq))
; ( pmet is_a_pseudometric_of the carrier of T & ( for pmet9 being RealMap of [:T,T:] st pmet = pmet9 holds
pmet9 is continuous ) )
A24:
for pq being Element of [: the carrier of T, the carrier of T:] holds pmet . pq = Sum (GeoF # pq)
A25:
for n being Nat ex pmet1 being Function of [: the carrier of T, the carrier of T:],REAL st
( GeoF . n = pmet1 & pmet1 is_a_pseudometric_of the carrier of T )
proof
let n be
Nat;
ex pmet1 being Function of [: the carrier of T, the carrier of T:],REAL st
( GeoF . n = pmet1 & pmet1 is_a_pseudometric_of the carrier of T )
consider pmet1 being
Function of
[: the carrier of T, the carrier of T:],
REAL such that A26:
FS2 . n = pmet1
and A27:
pmet1 is_a_pseudometric_of the
carrier of
T
and
for
pq being
Element of
[: the carrier of T, the carrier of T:] holds
pmet1 . pq <= s
and
for
pmet19 being
RealMap of
[:T,T:] st
pmet1 = pmet19 holds
pmet19 is
continuous
by A1;
deffunc H2(
Element of the
carrier of
T,
Element of the
carrier of
T)
-> Element of
REAL =
(((1 / 2) GeoSeq) . n) * (pmet1 . ($1,$2));
consider GF being
Function of
[: the carrier of T, the carrier of T:],
REAL such that A28:
for
p,
q being
Point of
T holds
GF . (
p,
q)
= H2(
p,
q)
from BINOP_1:sch 4();
now for a, b, c being Point of T holds
( GF . (a,a) = 0 & GF . (a,c) <= (GF . (a,b)) + (GF . (c,b)) )let a,
b,
c be
Point of
T;
( GF . (a,a) = 0 & GF . (a,c) <= (GF . (a,b)) + (GF . (c,b)) )
(1 / 2) |^ n > 0
by NEWTON:83;
then A29:
((1 / 2) GeoSeq) . n > 0
by PREPOWER:def 1;
pmet1 . (
a,
c)
<= (pmet1 . (a,b)) + (pmet1 . (c,b))
by A27, NAGATA_1:28;
then
(pmet1 . (a,c)) * (((1 / 2) GeoSeq) . n) <= ((pmet1 . (a,b)) + (pmet1 . (c,b))) * (((1 / 2) GeoSeq) . n)
by A29, XREAL_1:64;
then A30:
GF . (
a,
c)
<= ((((1 / 2) GeoSeq) . n) * (pmet1 . (a,b))) + ((((1 / 2) GeoSeq) . n) * (pmet1 . (c,b)))
by A28;
(
GF . (
a,
a)
= (((1 / 2) GeoSeq) . n) * (pmet1 . (a,a)) &
pmet1 . (
a,
a)
= 0 )
by A27, A28, NAGATA_1:28;
hence
GF . (
a,
a)
= 0
;
GF . (a,c) <= (GF . (a,b)) + (GF . (c,b))
(((1 / 2) GeoSeq) . n) * (pmet1 . (a,b)) = GF . (
a,
b)
by A28;
hence
GF . (
a,
c)
<= (GF . (a,b)) + (GF . (c,b))
by A28, A30;
verum end;
then A31:
GF is_a_pseudometric_of the
carrier of
T
by NAGATA_1:28;
A32:
GeoF . n = (((1 / 2) GeoSeq) . n) (#) (FS2 . n)
by A2;
then A33:
dom (FS2 . n) = dom (GeoF . n)
by VALUED_1:def 5;
A34:
now for x, y being object st [x,y] in dom (GeoF . n) holds
(GeoF . n) . (x,y) = GF . (x,y)let x,
y be
object ;
( [x,y] in dom (GeoF . n) implies (GeoF . n) . (x,y) = GF . (x,y) )assume A35:
[x,y] in dom (GeoF . n)
;
(GeoF . n) . (x,y) = GF . (x,y)then reconsider x9 =
x,
y9 =
y as
Point of
T by ZFMISC_1:87;
GF . (
x9,
y9)
= (((1 / 2) GeoSeq) . n) * (pmet1 . (x9,y9))
by A28;
hence
(GeoF . n) . (
x,
y)
= GF . (
x,
y)
by A26, A32, A35, VALUED_1:def 5;
verum end;
(
dom pmet1 = [: the carrier of T, the carrier of T:] &
dom GF = [: the carrier of T, the carrier of T:] )
by FUNCT_2:def 1;
hence
ex
pmet1 being
Function of
[: the carrier of T, the carrier of T:],
REAL st
(
GeoF . n = pmet1 &
pmet1 is_a_pseudometric_of the
carrier of
T )
by A26, A33, A34, A31, BINOP_1:20;
verum
end;
1 / 2 < 1
;
then
|.(1 / 2).| < 1
by ABSVALUE:def 1;
then A36:
(1 / 2) GeoSeq is summable
by SERIES_1:24;
A37:
for pq being Element of [: the carrier of T, the carrier of T:]
for pq9 being Point of [:T,T:] st pq = pq9 holds
GeoF # pq = GeoF9 # pq9
A39:
ex seq being Real_Sequence st
( seq is summable & ( for n being Nat
for pq9 being Point of [:T,T:] holds (GeoF9 # pq9) . n <= seq . n ) )
A40:
for pmet19 being RealMap of [:T,T:] st pmet = pmet19 holds
pmet19 is continuous
by A12, A24, A39, Th14;
for pq being Element of [: the carrier of T, the carrier of T:] holds GeoF # pq is summable
hence
( pmet is_a_pseudometric_of the carrier of T & ( for pmet9 being RealMap of [:T,T:] st pmet = pmet9 holds
pmet9 is continuous ) )
by A25, A24, A40, Th11; verum