let X be set ; for P being Function
for K1, K2 being SimplicialComplexStr of X st TopStruct(# the carrier of K1, the topology of K1 #) = TopStruct(# the carrier of K2, the topology of K2 #) holds
subdivision (P,K1) = subdivision (P,K2)
let P be Function; for K1, K2 being SimplicialComplexStr of X st TopStruct(# the carrier of K1, the topology of K1 #) = TopStruct(# the carrier of K2, the topology of K2 #) holds
subdivision (P,K1) = subdivision (P,K2)
let K1, K2 be SimplicialComplexStr of X; ( TopStruct(# the carrier of K1, the topology of K1 #) = TopStruct(# the carrier of K2, the topology of K2 #) implies subdivision (P,K1) = subdivision (P,K2) )
assume A1:
TopStruct(# the carrier of K1, the topology of K1 #) = TopStruct(# the carrier of K2, the topology of K2 #)
; subdivision (P,K1) = subdivision (P,K2)
set P1 = subdivision (P,K1);
set P2 = subdivision (P,K2);
A2:
( [#] K1 = [#] (subdivision (P,K1)) & [#] K2 = [#] (subdivision (P,K2)) )
by Def20;
A3:
the topology of (subdivision (P,K1)) c= the topology of (subdivision (P,K2))
proof
let x be
set ;
TARSKI:def 3 ( not x in the topology of (subdivision (P,K1)) or x in the topology of (subdivision (P,K2)) )
assume A4:
x in the
topology of
(subdivision (P,K1))
;
x in the topology of (subdivision (P,K2))
then reconsider A =
x as
Subset of
(subdivision (P,K1)) ;
reconsider A1 =
A as
Subset of
(subdivision (P,K2)) by A1, A2;
A is
simplex-like
by A4, PRE_TOPC:def 2;
then consider S being
c=-linear finite simplex-like Subset-Family of
K1 such that A5:
A = P .: S
by Def20;
reconsider S1 =
S as
Subset-Family of
K2 by A1;
S c= the
topology of
K1
by Th14;
then
S1 is
simplex-like
by A1, Th14;
then
A1 is
simplex-like
by A5, Def20;
hence
x in the
topology of
(subdivision (P,K2))
by PRE_TOPC:def 2;
verum
end;
the topology of (subdivision (P,K2)) c= the topology of (subdivision (P,K1))
proof
let x be
set ;
TARSKI:def 3 ( not x in the topology of (subdivision (P,K2)) or x in the topology of (subdivision (P,K1)) )
assume A6:
x in the
topology of
(subdivision (P,K2))
;
x in the topology of (subdivision (P,K1))
then reconsider A =
x as
Subset of
(subdivision (P,K2)) ;
reconsider A1 =
A as
Subset of
(subdivision (P,K1)) by A1, A2;
A is
simplex-like
by A6, PRE_TOPC:def 2;
then consider S being
c=-linear finite simplex-like Subset-Family of
K2 such that A7:
A = P .: S
by Def20;
reconsider S1 =
S as
Subset-Family of
K1 by A1;
S c= the
topology of
K2
by Th14;
then
S1 is
simplex-like
by A1, Th14;
then
A1 is
simplex-like
by A7, Def20;
hence
x in the
topology of
(subdivision (P,K1))
by PRE_TOPC:def 2;
verum
end;
hence
subdivision (P,K1) = subdivision (P,K2)
by A1, A2, A3, XBOOLE_0:def 10; verum