let Omega be non empty set ; for F being SigmaField of Omega
for jpi being pricefunction
for d, d2 being Nat st d > 0 & d2 = d - 1 holds
for Prob being Probability of F
for r being Real st r > - 1 holds
for G being sequence of (set_of_random_variables_on (F,Borel_Sets)) st Element_Of (F,Borel_Sets,G,0) = Omega --> (1 + r) holds
( Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d iff ex myphi being Real_Sequence st
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 ) )
let F be SigmaField of Omega; for jpi being pricefunction
for d, d2 being Nat st d > 0 & d2 = d - 1 holds
for Prob being Probability of F
for r being Real st r > - 1 holds
for G being sequence of (set_of_random_variables_on (F,Borel_Sets)) st Element_Of (F,Borel_Sets,G,0) = Omega --> (1 + r) holds
( Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d iff ex myphi being Real_Sequence st
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 ) )
let jpi be pricefunction ; for d, d2 being Nat st d > 0 & d2 = d - 1 holds
for Prob being Probability of F
for r being Real st r > - 1 holds
for G being sequence of (set_of_random_variables_on (F,Borel_Sets)) st Element_Of (F,Borel_Sets,G,0) = Omega --> (1 + r) holds
( Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d iff ex myphi being Real_Sequence st
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 ) )
let d, d2 be Nat; ( d > 0 & d2 = d - 1 implies for Prob being Probability of F
for r being Real st r > - 1 holds
for G being sequence of (set_of_random_variables_on (F,Borel_Sets)) st Element_Of (F,Borel_Sets,G,0) = Omega --> (1 + r) holds
( Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d iff ex myphi being Real_Sequence st
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 ) ) )
assume A1:
( d > 0 & d2 = d - 1 )
; for Prob being Probability of F
for r being Real st r > - 1 holds
for G being sequence of (set_of_random_variables_on (F,Borel_Sets)) st Element_Of (F,Borel_Sets,G,0) = Omega --> (1 + r) holds
( Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d iff ex myphi being Real_Sequence st
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 ) )
let Prob be Probability of F; for r being Real st r > - 1 holds
for G being sequence of (set_of_random_variables_on (F,Borel_Sets)) st Element_Of (F,Borel_Sets,G,0) = Omega --> (1 + r) holds
( Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d iff ex myphi being Real_Sequence st
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 ) )
let r be Real; ( r > - 1 implies for G being sequence of (set_of_random_variables_on (F,Borel_Sets)) st Element_Of (F,Borel_Sets,G,0) = Omega --> (1 + r) holds
( Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d iff ex myphi being Real_Sequence st
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 ) ) )
assume A2:
r > - 1
; for G being sequence of (set_of_random_variables_on (F,Borel_Sets)) st Element_Of (F,Borel_Sets,G,0) = Omega --> (1 + r) holds
( Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d iff ex myphi being Real_Sequence st
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 ) )
let G be sequence of (set_of_random_variables_on (F,Borel_Sets)); ( Element_Of (F,Borel_Sets,G,0) = Omega --> (1 + r) implies ( Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d iff ex myphi being Real_Sequence st
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 ) ) )
assume A3:
Element_Of (F,Borel_Sets,G,0) = Omega --> (1 + r)
; ( Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d iff ex myphi being Real_Sequence st
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 ) )
thus
( Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d implies ex myphi being Real_Sequence st
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 ) )
( ex myphi being Real_Sequence st
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 ) implies Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d )proof
assume
Arbitrage_Opportunity_exists_wrt Prob,
G,
jpi,
d
;
ex myphi being Real_Sequence st
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 )
then consider phi being
Real_Sequence such that C1:
(
BuyPortfolioExt (
phi,
jpi,
d)
<= 0 &
Prob . (ArbitrageElSigma1 (phi,Omega,F,G,d)) = 1 &
Prob . (ArbitrageElSigma2 (phi,Omega,F,G,d)) > 0 )
;
ArbitrageElSigma1 (
phi,
Omega,
F,
G,
d)
= { w where w is Element of Omega : PortfolioValueFutExt (d,phi,F,G,w) >= 0 }
by JB1;
then
ArbitrageElSigma1 (
phi,
Omega,
F,
G,
d)
c= { w where w is Element of Omega : PortfolioValueFut (d,phi,F,G,w) >= (1 + r) * (BuyPortfolio (phi,jpi,d)) }
by C1, A1, A2, A3, FINANCE1:14;
then C3:
ArbitrageElSigma1 (
phi,
Omega,
F,
G,
d)
c= ((RVPortfolioValueFut (phi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (phi,jpi,d))))) " [.0,+infty.[
by A1, JB2;
set RVspec =
((RVPortfolioValueFut (phi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (phi,jpi,d))))) " [.0,+infty.[;
reconsider RVspec =
((RVPortfolioValueFut (phi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (phi,jpi,d))))) " [.0,+infty.[ as
Event of
F by JB3;
( 1
<= Prob . RVspec &
Prob . RVspec <= 1 )
by PROB_1:35, C1, C3, PROB_1:34;
then Fin1:
1
= Prob . RVspec
by XXREAL_0:1;
ArbitrageElSigma2 (
phi,
Omega,
F,
G,
d)
= { w where w is Element of Omega : PortfolioValueFutExt (d,phi,F,G,w) > 0 }
by JC1;
then
ArbitrageElSigma2 (
phi,
Omega,
F,
G,
d)
c= { w where w is Element of Omega : PortfolioValueFut (d,phi,F,G,w) > (1 + r) * (BuyPortfolio (phi,jpi,d)) }
by C1, A1, A2, A3, FINANCE1:14;
then C3:
ArbitrageElSigma2 (
phi,
Omega,
F,
G,
d)
c= ((RVPortfolioValueFut (phi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (phi,jpi,d))))) " ].0,+infty.[
by A1, JC2;
set RVspec2 =
((RVPortfolioValueFut (phi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (phi,jpi,d))))) " ].0,+infty.[;
reconsider RVspec2 =
((RVPortfolioValueFut (phi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (phi,jpi,d))))) " ].0,+infty.[ as
Event of
F by JC3;
Prob . (ArbitrageElSigma2 (phi,Omega,F,G,d)) <= Prob . RVspec2
by C3, PROB_1:34;
hence
ex
myphi being
Real_Sequence st
(
Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 &
Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 )
by Fin1, C1;
verum
end;
given myphi being Real_Sequence such that ASS0:
( Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[) = 1 & Prob . (((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[) > 0 )
; Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d
deffunc H1( Nat) -> Element of REAL = In ((IFEQ ($1,0,(- (BuyPortfolio (myphi,jpi,d))),(myphi . $1))),REAL);
consider phi being Real_Sequence such that
AA1:
for n being Element of NAT holds phi . n = H1(n)
from FUNCT_2:sch 4();
AA10:
for n being Nat holds
( ( n = 0 implies phi . n = - (BuyPortfolio (myphi,jpi,d)) ) & ( n > 0 implies phi . n = myphi . n ) )
proof
let n be
Nat;
( ( n = 0 implies phi . n = - (BuyPortfolio (myphi,jpi,d)) ) & ( n > 0 implies phi . n = myphi . n ) )
SS:
n in NAT
by ORDINAL1:def 12;
SU:
myphi . n in REAL
;
SW:
IFEQ (
n,
0,
(- (BuyPortfolio (myphi,jpi,d))),
(myphi . n))
in REAL
proof
per cases
( n = 0 or n <> 0 )
;
suppose
n = 0
;
IFEQ (n,0,(- (BuyPortfolio (myphi,jpi,d))),(myphi . n)) in REAL then
IFEQ (
n,
0,
(- (BuyPortfolio (myphi,jpi,d))),
(myphi . n))
= - (BuyPortfolio (myphi,jpi,d))
by FUNCOP_1:def 8;
hence
IFEQ (
n,
0,
(- (BuyPortfolio (myphi,jpi,d))),
(myphi . n))
in REAL
by XREAL_0:def 1;
verum end; end;
end;
hereby ( n > 0 implies phi . n = myphi . n )
assume SQ:
n = 0
;
phi . n = - (BuyPortfolio (myphi,jpi,d))then phi . n =
H1(
n)
by AA1
.=
IFEQ (
n,
0,
(- (BuyPortfolio (myphi,jpi,d))),
(myphi . n))
by SUBSET_1:def 8, SW
;
hence
phi . n = - (BuyPortfolio (myphi,jpi,d))
by FUNCOP_1:def 8, SQ;
verum
end;
assume SQ:
n > 0
;
phi . n = myphi . n
phi . n =
In (
(IFEQ (n,0,(- (BuyPortfolio (myphi,jpi,d))),(myphi . n))),
REAL)
by AA1, SS
.=
IFEQ (
n,
0,
(- (BuyPortfolio (myphi,jpi,d))),
(myphi . n))
by SUBSET_1:def 8, SW
;
hence
phi . n = myphi . n
by FUNCOP_1:def 8, SQ;
verum
end;
set B0 = - (BuyPortfolio (myphi,jpi,d));
Z1:
BuyPortfolioExt (phi,jpi,d) = 0
proof
BuyPortfolioExt (
phi,
jpi,
d)
= (- (BuyPortfolio (myphi,jpi,d))) + (BuyPortfolio (myphi,jpi,d))
proof
zw:
BuyPortfolioExt (
phi,
jpi,
d)
= (phi . 0) + (BuyPortfolio (phi,jpi,d))
by A1, FINANCE1:11;
(- (BuyPortfolio (phi,jpi,d))) + (BuyPortfolio (myphi,jpi,d)) = 0
proof
(Partial_Sums ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1)) . (d - 1) = (Partial_Sums ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1)) . (d - 1)
proof
set P1 =
Partial_Sums ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1);
set P2 =
Partial_Sums ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1);
defpred S1[
Nat]
means (Partial_Sums ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1)) . $1
= (Partial_Sums ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1)) . $1;
J0:
S1[
0 ]
proof
(Partial_Sums ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1)) . 0 = ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1) . 0
by SERIES_1:def 1;
then
(Partial_Sums ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1)) . 0 = (ElementsOfBuyPortfolio (phi,jpi)) . (0 + 1)
by NAT_1:def 3;
then Erg1:
(Partial_Sums ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1)) . 0 = (phi . 1) * (jpi . 1)
by VALUED_1:5;
(Partial_Sums ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1)) . 0 = ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1) . 0
by SERIES_1:def 1;
then
(Partial_Sums ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1)) . 0 = (ElementsOfBuyPortfolio (myphi,jpi)) . (0 + 1)
by NAT_1:def 3;
then
(Partial_Sums ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1)) . 0 = (myphi . 1) * (jpi . 1)
by VALUED_1:5;
hence
S1[
0 ]
by Erg1, AA10;
verum
end;
J1:
for
n being
Nat st
S1[
n] holds
S1[
n + 1]
proof
let n be
Nat;
( S1[n] implies S1[n + 1] )
assume f1:
S1[
n]
;
S1[n + 1]
(Partial_Sums ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1)) . (n + 1) = ((Partial_Sums ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1)) . n) + (((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1) . (n + 1))
by SERIES_1:def 1;
then
(Partial_Sums ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1)) . (n + 1) = ((Partial_Sums ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1)) . n) + ((ElementsOfBuyPortfolio (phi,jpi)) . ((n + 1) + 1))
by NAT_1:def 3;
then Erg1:
(Partial_Sums ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1)) . (n + 1) = ((Partial_Sums ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1)) . n) + ((phi . (n + 2)) * (jpi . (n + 2)))
by VALUED_1:5;
set n2 =
n + 2;
(Partial_Sums ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1)) . (n + 1) = ((Partial_Sums ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1)) . n) + (((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1) . (n + 1))
by SERIES_1:def 1;
then
(Partial_Sums ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1)) . (n + 1) = ((Partial_Sums ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1)) . n) + ((ElementsOfBuyPortfolio (myphi,jpi)) . ((n + 1) + 1))
by NAT_1:def 3;
then
(Partial_Sums ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1)) . (n + 1) = ((Partial_Sums ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1)) . n) + ((myphi . (n + 2)) * (jpi . (n + 2)))
by VALUED_1:5;
hence
S1[
n + 1]
by Erg1, f1, AA10;
verum
end;
for
n being
Nat holds
S1[
n]
from NAT_1:sch 2(J0, J1);
hence
(Partial_Sums ((ElementsOfBuyPortfolio (phi,jpi)) ^\ 1)) . (d - 1) = (Partial_Sums ((ElementsOfBuyPortfolio (myphi,jpi)) ^\ 1)) . (d - 1)
by A1;
verum
end;
hence
(- (BuyPortfolio (phi,jpi,d))) + (BuyPortfolio (myphi,jpi,d)) = 0
;
verum
end;
hence
BuyPortfolioExt (
phi,
jpi,
d)
= (- (BuyPortfolio (myphi,jpi,d))) + (BuyPortfolio (myphi,jpi,d))
by zw, AA10;
verum
end;
hence
BuyPortfolioExt (
phi,
jpi,
d)
= 0
;
verum
end;
Z2:
Prob . (ArbitrageElSigma1 (phi,Omega,F,G,d)) = 1
proof
set Set1 =
RVPortfolioValueFutExt (
phi,
F,
G,
d);
set Set2 =
(RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))));
(RVPortfolioValueFutExt (phi,F,G,d)) " [.0,+infty.[ = ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[
proof
for
x being
object holds
(
x in (RVPortfolioValueFutExt (phi,F,G,d)) " [.0,+infty.[ iff
x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[ )
proof
let x be
object ;
( x in (RVPortfolioValueFutExt (phi,F,G,d)) " [.0,+infty.[ iff x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[ )
thus
(
x in (RVPortfolioValueFutExt (phi,F,G,d)) " [.0,+infty.[ implies
x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[ )
( x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[ implies x in (RVPortfolioValueFutExt (phi,F,G,d)) " [.0,+infty.[ )proof
assume sc:
x in (RVPortfolioValueFutExt (phi,F,G,d)) " [.0,+infty.[
;
x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[
then reconsider x =
x as
Element of
Omega ;
(RVPortfolioValueFutExt (phi,F,G,d)) . x in [.0,+infty.[
by sc, FUNCT_1:def 7;
then
PortfolioValueFutExt (
d,
phi,
F,
G,
x)
in [.0,+infty.[
by FINANCE3:def 1;
then e:
((1 + r) * (phi . 0)) + (PortfolioValueFut ((d2 + 1),phi,F,G,x)) in [.0,+infty.[
by A1, A3, FINANCE1:12;
(
x in dom ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) &
((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) . x in [.0,+infty.[ )
proof
- ((Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))) . x) = (1 + r) * (- (BuyPortfolio (myphi,jpi,d)))
;
then uuu0:
(1 + r) * (phi . 0) = - ((Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))) . x)
by AA10;
(RVPortfolioValueFut (myphi,F,G,d2)) . x = (RVPortfolioValueFut (phi,F,G,d2)) . x
proof
iii:
(RVPortfolioValueFut (myphi,F,G,d2)) . x = PortfolioValueFut (
(d2 + 1),
myphi,
F,
G,
x)
by FINANCE3:def 3;
defpred S1[
Nat]
means (Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . $1
= (Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . $1;
K1:
S1[
0 ]
proof
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . 0
by SERIES_1:def 1;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . 0 = (ElementsOfPortfolioValue_fut (myphi,F,x,G)) . (0 + 1)
by NAT_1:def 3;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValueProb_fut (F,(G . 1))) . x) * (myphi . 1)
by FINANCE1:def 10;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValueProb_fut (F,(G . 1))) . x) * (phi . 1)
by AA10;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . 0 = (ElementsOfPortfolioValue_fut (phi,F,x,G)) . (0 + 1)
by FINANCE1:def 10;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . 0
by NAT_1:def 3;
hence
S1[
0 ]
by SERIES_1:def 1;
verum
end;
K2:
for
n being
Nat st
S1[
n] holds
S1[
n + 1]
proof
let n be
Nat;
( S1[n] implies S1[n + 1] )
assume AK2:
S1[
n]
;
S1[n + 1]
set n1 =
n + 1;
set n2 =
(n + 1) + 1;
R:
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . (n + 1) = ((Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . n) + (((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1))
by AK2, SERIES_1:def 1;
((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1) = (ElementsOfPortfolioValue_fut (myphi,F,x,G)) . ((n + 1) + 1)
by NAT_1:def 3;
then R1:
((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValueProb_fut (F,(G . ((n + 1) + 1)))) . x) * (myphi . ((n + 1) + 1))
by FINANCE1:def 10;
((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1)
proof
((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValueProb_fut (F,(G . ((n + 1) + 1)))) . x) * (phi . ((n + 1) + 1))
by R1, AA10;
then
((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1) = (ElementsOfPortfolioValue_fut (phi,F,x,G)) . ((n + 1) + 1)
by FINANCE1:def 10;
hence
((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1)
by NAT_1:def 3;
verum
end;
hence
S1[
n + 1]
by SERIES_1:def 1, R;
verum
end;
for
n being
Nat holds
S1[
n]
from NAT_1:sch 2(K1, K2);
then
(RVPortfolioValueFut (myphi,F,G,d2)) . x = PortfolioValueFut (
(d2 + 1),
phi,
F,
G,
x)
by iii;
hence
(RVPortfolioValueFut (myphi,F,G,d2)) . x = (RVPortfolioValueFut (phi,F,G,d2)) . x
by FINANCE3:def 3;
verum
end;
then UUU:
((RVPortfolioValueFut (myphi,F,G,d2)) . x) - ((Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))) . x) in [.0,+infty.[
by uuu0, e, FINANCE3:def 3;
x in dom ((RVPortfolioValueFut (myphi,F,G,d2)) + (- (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))))
proof
(
dom (RVPortfolioValueFut (myphi,F,G,d2)) = Omega &
dom (- (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) = Omega )
by FUNCT_2:def 1;
then
(dom (RVPortfolioValueFut (myphi,F,G,d2))) /\ (dom (- (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))))) = Omega
;
then
dom ((RVPortfolioValueFut (myphi,F,G,d2)) + (- (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))))) = Omega
by VALUED_1:def 1;
hence
x in dom ((RVPortfolioValueFut (myphi,F,G,d2)) + (- (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))))
;
verum
end;
hence
(
x in dom ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) &
((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) . x in [.0,+infty.[ )
by UUU, VALUED_1:13;
verum
end;
hence
x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[
by FUNCT_1:def 7;
verum
end;
assume ab:
x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[
;
x in (RVPortfolioValueFutExt (phi,F,G,d)) " [.0,+infty.[
then ABC1:
(
x in dom ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) &
((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) . x in [.0,+infty.[ )
by FUNCT_1:def 7;
reconsider x =
x as
Element of
Omega by ab;
ABC3:
((RVPortfolioValueFut (myphi,F,G,d2)) . x) - ((Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))) . x) in [.0,+infty.[
by ABC1, VALUED_1:13;
- ((Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))) . x) = (1 + r) * (phi . 0)
then ABC4:
(PortfolioValueFut ((d2 + 1),myphi,F,G,x)) + ((1 + r) * (phi . 0)) in [.0,+infty.[
by FINANCE3:def 3, ABC3;
ABC2:
(RVPortfolioValueFutExt (phi,F,G,d)) . x in [.0,+infty.[
proof
PortfolioValueFut (
(d2 + 1),
phi,
F,
G,
x)
= PortfolioValueFut (
(d2 + 1),
myphi,
F,
G,
x)
proof
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . d2 = (Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . d2
proof
defpred S1[
Nat]
means (Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . $1
= (Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . $1;
K1:
S1[
0 ]
proof
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . 0
by SERIES_1:def 1;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . 0 = (ElementsOfPortfolioValue_fut (phi,F,x,G)) . (0 + 1)
by NAT_1:def 3;
then R:
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValueProb_fut (F,(G . 1))) . x) * (phi . 1)
by FINANCE1:def 10;
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValueProb_fut (F,(G . 1))) . x) * (myphi . 1)
by R, AA10;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . 0 = (ElementsOfPortfolioValue_fut (myphi,F,x,G)) . (0 + 1)
by FINANCE1:def 10;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . 0
by NAT_1:def 3;
hence
S1[
0 ]
by SERIES_1:def 1;
verum
end;
K2:
for
n being
Nat st
S1[
n] holds
S1[
n + 1]
proof
let n be
Nat;
( S1[n] implies S1[n + 1] )
set n1 =
n + 1;
set n2 =
(n + 1) + 1;
assume
S1[
n]
;
S1[n + 1]
then R:
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . (n + 1) = ((Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . n) + (((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1))
by SERIES_1:def 1;
((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1)
proof
((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1) = (ElementsOfPortfolioValue_fut (phi,F,x,G)) . ((n + 1) + 1)
by NAT_1:def 3;
then QA:
((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValueProb_fut (F,(G . ((n + 1) + 1)))) . x) * (phi . ((n + 1) + 1))
by FINANCE1:def 10;
phi . ((n + 1) + 1) = myphi . ((n + 1) + 1)
by AA10;
then
((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1) = (ElementsOfPortfolioValue_fut (myphi,F,x,G)) . ((n + 1) + 1)
by FINANCE1:def 10, QA;
hence
((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1)
by NAT_1:def 3;
verum
end;
hence
S1[
n + 1]
by SERIES_1:def 1, R;
verum
end;
for
n being
Nat holds
S1[
n]
from NAT_1:sch 2(K1, K2);
hence
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . d2 = (Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . d2
;
verum
end;
hence
PortfolioValueFut (
(d2 + 1),
phi,
F,
G,
x)
= PortfolioValueFut (
(d2 + 1),
myphi,
F,
G,
x)
;
verum
end;
then
PortfolioValueFutExt (
(d2 + 1),
phi,
F,
G,
x)
in [.0,+infty.[
by A3, FINANCE1:12, ABC4;
hence
(RVPortfolioValueFutExt (phi,F,G,d)) . x in [.0,+infty.[
by A1, FINANCE3:def 1;
verum
end;
dom (RVPortfolioValueFutExt (phi,F,G,d)) = Omega
by FUNCT_2:def 1;
hence
x in (RVPortfolioValueFutExt (phi,F,G,d)) " [.0,+infty.[
by FUNCT_1:def 7, ABC2;
verum
end;
hence
(RVPortfolioValueFutExt (phi,F,G,d)) " [.0,+infty.[ = ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " [.0,+infty.[
by TARSKI:2;
verum
end;
hence
Prob . (ArbitrageElSigma1 (phi,Omega,F,G,d)) = 1
by ASS0;
verum
end;
Prob . (ArbitrageElSigma2 (phi,Omega,F,G,d)) > 0
proof
(RVPortfolioValueFutExt (phi,F,G,d)) " ].0,+infty.[ = ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[
proof
set Set1 =
RVPortfolioValueFutExt (
phi,
F,
G,
d);
set Set2 =
(RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))));
for
x being
object holds
(
x in (RVPortfolioValueFutExt (phi,F,G,d)) " ].0,+infty.[ iff
x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[ )
proof
let x be
object ;
( x in (RVPortfolioValueFutExt (phi,F,G,d)) " ].0,+infty.[ iff x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[ )
thus
(
x in (RVPortfolioValueFutExt (phi,F,G,d)) " ].0,+infty.[ implies
x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[ )
( x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[ implies x in (RVPortfolioValueFutExt (phi,F,G,d)) " ].0,+infty.[ )proof
assume ss:
x in (RVPortfolioValueFutExt (phi,F,G,d)) " ].0,+infty.[
;
x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[
then s:
(
x in dom (RVPortfolioValueFutExt (phi,F,G,d)) &
(RVPortfolioValueFutExt (phi,F,G,d)) . x in ].0,+infty.[ )
by FUNCT_1:def 7;
reconsider x =
x as
Element of
Omega by ss;
PortfolioValueFutExt (
d,
phi,
F,
G,
x)
in ].0,+infty.[
by FINANCE3:def 1, s;
then e:
((1 + r) * (phi . 0)) + (PortfolioValueFut ((d2 + 1),phi,F,G,x)) in ].0,+infty.[
by A1, A3, FINANCE1:12;
- ((Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))) . x) = (1 + r) * (- (BuyPortfolio (myphi,jpi,d)))
;
then uuu0:
(1 + r) * (phi . 0) = - ((Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))) . x)
by AA10;
iii:
(RVPortfolioValueFut (myphi,F,G,d2)) . x = PortfolioValueFut (
(d2 + 1),
myphi,
F,
G,
x)
by FINANCE3:def 3;
(
x in dom ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) &
((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) . x in ].0,+infty.[ )
proof
(RVPortfolioValueFut (myphi,F,G,d2)) . x = (RVPortfolioValueFut (phi,F,G,d2)) . x
proof
defpred S1[
Nat]
means (Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . $1
= (Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . $1;
K1:
S1[
0 ]
proof
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . 0
by SERIES_1:def 1;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . 0 = (ElementsOfPortfolioValue_fut (myphi,F,x,G)) . (0 + 1)
by NAT_1:def 3;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValueProb_fut (F,(G . 1))) . x) * (myphi . 1)
by FINANCE1:def 10;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValueProb_fut (F,(G . 1))) . x) * (phi . 1)
by AA10;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . 0 = (ElementsOfPortfolioValue_fut (phi,F,x,G)) . (0 + 1)
by FINANCE1:def 10;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . 0
by NAT_1:def 3;
hence
S1[
0 ]
by SERIES_1:def 1;
verum
end;
K2:
for
n being
Nat st
S1[
n] holds
S1[
n + 1]
proof
let n be
Nat;
( S1[n] implies S1[n + 1] )
assume AK2:
S1[
n]
;
S1[n + 1]
set n1 =
n + 1;
set n2 =
(n + 1) + 1;
R:
(Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . (n + 1) = ((Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . n) + (((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1))
by AK2, SERIES_1:def 1;
((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1)
proof
((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1) = (ElementsOfPortfolioValue_fut (myphi,F,x,G)) . ((n + 1) + 1)
by NAT_1:def 3;
then R1:
((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValueProb_fut (F,(G . ((n + 1) + 1)))) . x) * (myphi . ((n + 1) + 1))
by FINANCE1:def 10;
((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValueProb_fut (F,(G . ((n + 1) + 1)))) . x) * (phi . ((n + 1) + 1))
by R1, AA10;
then
((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1) = (ElementsOfPortfolioValue_fut (phi,F,x,G)) . ((n + 1) + 1)
by FINANCE1:def 10;
hence
((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1)
by NAT_1:def 3;
verum
end;
hence
S1[
n + 1]
by SERIES_1:def 1, R;
verum
end;
for
n being
Nat holds
S1[
n]
from NAT_1:sch 2(K1, K2);
then
(RVPortfolioValueFut (myphi,F,G,d2)) . x = PortfolioValueFut (
(d2 + 1),
phi,
F,
G,
x)
by iii;
hence
(RVPortfolioValueFut (myphi,F,G,d2)) . x = (RVPortfolioValueFut (phi,F,G,d2)) . x
by FINANCE3:def 3;
verum
end;
then UUU:
((RVPortfolioValueFut (myphi,F,G,d2)) . x) - ((Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))) . x) in ].0,+infty.[
by uuu0, e, FINANCE3:def 3;
x in dom ((RVPortfolioValueFut (myphi,F,G,d2)) + (- (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))))
proof
(
dom (RVPortfolioValueFut (myphi,F,G,d2)) = Omega &
dom (- (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) = Omega )
by FUNCT_2:def 1;
then
(dom (RVPortfolioValueFut (myphi,F,G,d2))) /\ (dom (- (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))))) = Omega
;
then
dom ((RVPortfolioValueFut (myphi,F,G,d2)) + (- (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))))) = Omega
by VALUED_1:def 1;
hence
x in dom ((RVPortfolioValueFut (myphi,F,G,d2)) + (- (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))))
;
verum
end;
hence
(
x in dom ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) &
((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) . x in ].0,+infty.[ )
by UUU, VALUED_1:13;
verum
end;
hence
x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[
by FUNCT_1:def 7;
verum
end;
assume ab:
x in ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[
;
x in (RVPortfolioValueFutExt (phi,F,G,d)) " ].0,+infty.[
then ABC1:
(
x in dom ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) &
((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) . x in ].0,+infty.[ )
by FUNCT_1:def 7;
reconsider x =
x as
Element of
Omega by ab;
ABC3:
((RVPortfolioValueFut (myphi,F,G,d2)) . x) - ((Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))) . x) in ].0,+infty.[
by ABC1, VALUED_1:13;
- ((Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))) . x) = (1 + r) * (- (BuyPortfolio (myphi,jpi,d)))
;
then
- ((Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d)))) . x) = (1 + r) * (phi . 0)
by AA10;
then ABC4:
(PortfolioValueFut ((d2 + 1),myphi,F,G,x)) + ((1 + r) * (phi . 0)) in ].0,+infty.[
by FINANCE3:def 3, ABC3;
ABC2:
(RVPortfolioValueFutExt (phi,F,G,d)) . x in ].0,+infty.[
proof
PortfolioValueFut (
(d2 + 1),
phi,
F,
G,
x)
= PortfolioValueFut (
(d2 + 1),
myphi,
F,
G,
x)
proof
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . d2 = (Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . d2
proof
defpred S1[
Nat]
means (Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . $1
= (Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . $1;
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . 0
by SERIES_1:def 1;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . 0 = (ElementsOfPortfolioValue_fut (phi,F,x,G)) . (0 + 1)
by NAT_1:def 3;
then R:
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValueProb_fut (F,(G . 1))) . x) * (phi . 1)
by FINANCE1:def 10;
K1:
S1[
0 ]
proof
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValueProb_fut (F,(G . 1))) . x) * (myphi . 1)
by R, AA10;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . 0 = (ElementsOfPortfolioValue_fut (myphi,F,x,G)) . (0 + 1)
by FINANCE1:def 10;
then
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . 0 = ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . 0
by NAT_1:def 3;
hence
S1[
0 ]
by SERIES_1:def 1;
verum
end;
K2:
for
n being
Nat st
S1[
n] holds
S1[
n + 1]
proof
let n be
Nat;
( S1[n] implies S1[n + 1] )
set n1 =
n + 1;
set n2 =
(n + 1) + 1;
assume
S1[
n]
;
S1[n + 1]
then R:
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . (n + 1) = ((Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . n) + (((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1))
by SERIES_1:def 1;
((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1)
proof
((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1) = (ElementsOfPortfolioValue_fut (phi,F,x,G)) . ((n + 1) + 1)
by NAT_1:def 3;
then QA:
((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValueProb_fut (F,(G . ((n + 1) + 1)))) . x) * (phi . ((n + 1) + 1))
by FINANCE1:def 10;
phi . ((n + 1) + 1) = myphi . ((n + 1) + 1)
by AA10;
then
((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1) = (ElementsOfPortfolioValue_fut (myphi,F,x,G)) . ((n + 1) + 1)
by FINANCE1:def 10, QA;
hence
((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1) . (n + 1) = ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1) . (n + 1)
by NAT_1:def 3;
verum
end;
hence
S1[
n + 1]
by SERIES_1:def 1, R;
verum
end;
for
n being
Nat holds
S1[
n]
from NAT_1:sch 2(K1, K2);
hence
(Partial_Sums ((ElementsOfPortfolioValue_fut (phi,F,x,G)) ^\ 1)) . d2 = (Partial_Sums ((ElementsOfPortfolioValue_fut (myphi,F,x,G)) ^\ 1)) . d2
;
verum
end;
hence
PortfolioValueFut (
(d2 + 1),
phi,
F,
G,
x)
= PortfolioValueFut (
(d2 + 1),
myphi,
F,
G,
x)
;
verum
end;
then
PortfolioValueFutExt (
(d2 + 1),
phi,
F,
G,
x)
in ].0,+infty.[
by A3, FINANCE1:12, ABC4;
hence
(RVPortfolioValueFutExt (phi,F,G,d)) . x in ].0,+infty.[
by A1, FINANCE3:def 1;
verum
end;
dom (RVPortfolioValueFutExt (phi,F,G,d)) = Omega
by FUNCT_2:def 1;
hence
x in (RVPortfolioValueFutExt (phi,F,G,d)) " ].0,+infty.[
by FUNCT_1:def 7, ABC2;
verum
end;
hence
(RVPortfolioValueFutExt (phi,F,G,d)) " ].0,+infty.[ = ((RVPortfolioValueFut (myphi,F,G,d2)) - (Omega --> ((1 + r) * (BuyPortfolio (myphi,jpi,d))))) " ].0,+infty.[
by TARSKI:2;
verum
end;
hence
Prob . (ArbitrageElSigma2 (phi,Omega,F,G,d)) > 0
by ASS0;
verum
end;
hence
Arbitrage_Opportunity_exists_wrt Prob,G,jpi,d
by Z1, Z2; verum