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Theorem trilpo 16968
Description: Real number trichotomy implies the Limited Principle of Omniscience (LPO). We expect that we'd need some form of countable choice to prove the converse.

Here's the outline of the proof. Given an infinite sequence F of zeroes and ones, we need to show the sequence contains a zero or it is all ones. Construct a real number A whose representation in base two consists of a zero, a decimal point, and then the numbers of the sequence. Compare it with one using trichotomy. The three cases from trichotomy are trilpolemlt1 16966 (which means the sequence contains a zero), trilpolemeq1 16965 (which means the sequence is all ones), and trilpolemgt1 16964 (which is not possible).

Equivalent ways to state real number trichotomy (sometimes called "analytic LPO") include decidability of real number apartness (see triap 16954) or that the real numbers are a discrete field (see trirec0 16969).

LPO is known to not be provable in IZF (and most constructive foundations), so this theorem establishes that we will be unable to prove an analogue to qtri3or 10628 for real numbers. (Contributed by Jim Kingdon, 23-Aug-2023.)

Assertion
Ref Expression
trilpo  |-  ( A. x  e.  RR  A. y  e.  RR  ( x  < 
y  \/  x  =  y  \/  y  < 
x )  ->  om  e. Omni )
Distinct variable group:    x, y

Proof of Theorem trilpo
Dummy variables  f  i  j  z are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 elmapi 6918 . . . . . 6  |-  ( f  e.  ( { 0 ,  1 }  ^m  NN )  ->  f : NN --> { 0 ,  1 } )
21adantl 277 . . . . 5  |-  ( ( A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x )  /\  f  e.  ( {
0 ,  1 }  ^m  NN ) )  ->  f : NN --> { 0 ,  1 } )
3 oveq2 6067 . . . . . . . 8  |-  ( i  =  j  ->  (
2 ^ i )  =  ( 2 ^ j ) )
43oveq2d 6075 . . . . . . 7  |-  ( i  =  j  ->  (
1  /  ( 2 ^ i ) )  =  ( 1  / 
( 2 ^ j
) ) )
5 fveq2 5676 . . . . . . 7  |-  ( i  =  j  ->  (
f `  i )  =  ( f `  j ) )
64, 5oveq12d 6077 . . . . . 6  |-  ( i  =  j  ->  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  =  ( ( 1  /  ( 2 ^ j ) )  x.  ( f `  j
) ) )
76cbvsumv 12076 . . . . 5  |-  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  =  sum_ j  e.  NN  (
( 1  /  (
2 ^ j ) )  x.  ( f `
 j ) )
82, 7trilpolemcl 16962 . . . . . 6  |-  ( ( A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x )  /\  f  e.  ( {
0 ,  1 }  ^m  NN ) )  ->  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  e.  RR )
9 1red 8306 . . . . . 6  |-  ( ( A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x )  /\  f  e.  ( {
0 ,  1 }  ^m  NN ) )  ->  1  e.  RR )
10 simpl 109 . . . . . 6  |-  ( ( A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x )  /\  f  e.  ( {
0 ,  1 }  ^m  NN ) )  ->  A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x ) )
11 breq1 4118 . . . . . . . 8  |-  ( x  =  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  ->  ( x  <  y  <->  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  <  y )
)
12 eqeq1 2241 . . . . . . . 8  |-  ( x  =  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  ->  ( x  =  y  <->  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  =  y ) )
13 breq2 4119 . . . . . . . 8  |-  ( x  =  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  ->  ( y  <  x  <->  y  <  sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) ) ) )
1411, 12, 133orbi123d 1348 . . . . . . 7  |-  ( x  =  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  ->  ( (
x  <  y  \/  x  =  y  \/  y  <  x )  <->  ( sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  <  y  \/  sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  =  y  \/  y  <  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
) ) ) )
15 breq2 4119 . . . . . . . 8  |-  ( y  =  1  ->  ( sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  <  y  <->  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  <  1
) )
16 eqeq2 2244 . . . . . . . 8  |-  ( y  =  1  ->  ( sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  =  y  <->  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  =  1 ) )
17 breq1 4118 . . . . . . . 8  |-  ( y  =  1  ->  (
y  <  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  <->  1  <  sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) ) ) )
1815, 16, 173orbi123d 1348 . . . . . . 7  |-  ( y  =  1  ->  (
( sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  <  y  \/  sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  =  y  \/  y  <  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
) )  <->  ( sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  <  1  \/  sum_ i  e.  NN  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  =  1  \/  1  <  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
) ) ) )
1914, 18rspc2va 2938 . . . . . 6  |-  ( ( ( sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  e.  RR  /\  1  e.  RR )  /\  A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x ) )  ->  ( sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  <  1  \/  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  =  1  \/  1  <  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) ) ) )
208, 9, 10, 19syl21anc 1273 . . . . 5  |-  ( ( A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x )  /\  f  e.  ( {
0 ,  1 }  ^m  NN ) )  ->  ( sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  <  1  \/  sum_ i  e.  NN  ( ( 1  / 
( 2 ^ i
) )  x.  (
f `  i )
)  =  1  \/  1  <  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) ) ) )
212, 7, 20trilpolemres 16967 . . . 4  |-  ( ( A. x  e.  RR  A. y  e.  RR  (
x  <  y  \/  x  =  y  \/  y  <  x )  /\  f  e.  ( {
0 ,  1 }  ^m  NN ) )  ->  ( E. z  e.  NN  ( f `  z )  =  0  \/  A. z  e.  NN  ( f `  z )  =  1 ) )
2221ralrimiva 2617 . . 3  |-  ( A. x  e.  RR  A. y  e.  RR  ( x  < 
y  \/  x  =  y  \/  y  < 
x )  ->  A. f  e.  ( { 0 ,  1 }  ^m  NN ) ( E. z  e.  NN  ( f `  z )  =  0  \/  A. z  e.  NN  ( f `  z )  =  1 ) )
23 nnex 9264 . . . 4  |-  NN  e.  _V
24 isomninn 16956 . . . 4  |-  ( NN  e.  _V  ->  ( NN  e. Omni 
<-> 
A. f  e.  ( { 0 ,  1 }  ^m  NN ) ( E. z  e.  NN  ( f `  z )  =  0  \/  A. z  e.  NN  ( f `  z )  =  1 ) ) )
2523, 24ax-mp 5 . . 3  |-  ( NN  e. Omni 
<-> 
A. f  e.  ( { 0 ,  1 }  ^m  NN ) ( E. z  e.  NN  ( f `  z )  =  0  \/  A. z  e.  NN  ( f `  z )  =  1 ) )
2622, 25sylibr 134 . 2  |-  ( A. x  e.  RR  A. y  e.  RR  ( x  < 
y  \/  x  =  y  \/  y  < 
x )  ->  NN  e. Omni )
27 nnenom 10824 . . 3  |-  NN  ~~  om
28 enomni 7444 . . 3  |-  ( NN 
~~  om  ->  ( NN  e. Omni 
<->  om  e. Omni ) )
2927, 28ax-mp 5 . 2  |-  ( NN  e. Omni 
<->  om  e. Omni )
3026, 29sylib 122 1  |-  ( A. x  e.  RR  A. y  e.  RR  ( x  < 
y  \/  x  =  y  \/  y  < 
x )  ->  om  e. Omni )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 104    <-> wb 105    \/ wo 716    \/ w3o 1004    = wceq 1398    e. wcel 2205   A.wral 2522   E.wrex 2523   _Vcvv 2815   {cpr 3696   class class class wbr 4115   omcom 4718   -->wf 5354   ` cfv 5358  (class class class)co 6059    ^m cmap 6896    ~~ cen 6987  Omnicomni 7439   RRcr 8143   0cc0 8144   1c1 8145    x. cmul 8149    < clt 8325    / cdiv 8967   NNcn 9258   2c2 9309   ^cexp 10928   sum_csu 12068
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 619  ax-in2 620  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2207  ax-14 2208  ax-ext 2216  ax-coll 4231  ax-sep 4234  ax-nul 4242  ax-pow 4293  ax-pr 4328  ax-un 4560  ax-setind 4665  ax-iinf 4716  ax-cnex 8235  ax-resscn 8236  ax-1cn 8237  ax-1re 8238  ax-icn 8239  ax-addcl 8240  ax-addrcl 8241  ax-mulcl 8242  ax-mulrcl 8243  ax-addcom 8244  ax-mulcom 8245  ax-addass 8246  ax-mulass 8247  ax-distr 8248  ax-i2m1 8249  ax-0lt1 8250  ax-1rid 8251  ax-0id 8252  ax-rnegex 8253  ax-precex 8254  ax-cnre 8255  ax-pre-ltirr 8256  ax-pre-ltwlin 8257  ax-pre-lttrn 8258  ax-pre-apti 8259  ax-pre-ltadd 8260  ax-pre-mulgt0 8261  ax-pre-mulext 8262  ax-arch 8263  ax-caucvg 8264
This theorem depends on definitions:  df-bi 117  df-dc 843  df-3or 1006  df-3an 1007  df-tru 1401  df-fal 1404  df-nf 1510  df-sb 1812  df-eu 2085  df-mo 2086  df-clab 2221  df-cleq 2227  df-clel 2230  df-nfc 2375  df-ne 2415  df-nel 2510  df-ral 2527  df-rex 2528  df-reu 2529  df-rmo 2530  df-rab 2531  df-v 2817  df-sbc 3046  df-csb 3142  df-dif 3216  df-un 3218  df-in 3220  df-ss 3227  df-nul 3513  df-if 3626  df-pw 3677  df-sn 3701  df-pr 3702  df-op 3704  df-uni 3921  df-int 3956  df-iun 3999  df-br 4116  df-opab 4178  df-mpt 4179  df-tr 4215  df-id 4420  df-po 4423  df-iso 4424  df-iord 4493  df-on 4495  df-ilim 4496  df-suc 4498  df-iom 4719  df-xp 4761  df-rel 4762  df-cnv 4763  df-co 4764  df-dm 4765  df-rn 4766  df-res 4767  df-ima 4768  df-iota 5318  df-fun 5360  df-fn 5361  df-f 5362  df-f1 5363  df-fo 5364  df-f1o 5365  df-fv 5366  df-isom 5367  df-riota 6012  df-ov 6062  df-oprab 6063  df-mpo 6064  df-1st 6348  df-2nd 6349  df-recs 6550  df-irdg 6615  df-frec 6636  df-1o 6661  df-2o 6662  df-oadd 6665  df-er 6781  df-map 6898  df-en 6990  df-dom 6991  df-fin 6992  df-omni 7440  df-pnf 8327  df-mnf 8328  df-xr 8329  df-ltxr 8330  df-le 8331  df-sub 8464  df-neg 8465  df-reap 8868  df-ap 8875  df-div 8968  df-inn 9259  df-2 9317  df-3 9318  df-4 9319  df-n0 9518  df-z 9599  df-uz 9876  df-q 9974  df-rp 10009  df-ico 10250  df-fz 10366  df-fzo 10503  df-seqfrec 10838  df-exp 10929  df-ihash 11168  df-cj 11556  df-re 11557  df-im 11558  df-rsqrt 11713  df-abs 11714  df-clim 11994  df-sumdc 12069
This theorem is referenced by: (None)
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