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Theorem trilpo 16019
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 16017 (which means the sequence contains a zero), trilpolemeq1 16016 (which means the sequence is all ones), and trilpolemgt1 16015 (which is not possible).

Equivalent ways to state real number trichotomy (sometimes called "analytic LPO") include decidability of real number apartness (see triap 16005) or that the real numbers are a discrete field (see trirec0 16020).

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 10385 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 6759 . . . . . 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 5954 . . . . . . . 8  |-  ( i  =  j  ->  (
2 ^ i )  =  ( 2 ^ j ) )
43oveq2d 5962 . . . . . . 7  |-  ( i  =  j  ->  (
1  /  ( 2 ^ i ) )  =  ( 1  / 
( 2 ^ j
) ) )
5 fveq2 5578 . . . . . . 7  |-  ( i  =  j  ->  (
f `  i )  =  ( f `  j ) )
64, 5oveq12d 5964 . . . . . 6  |-  ( i  =  j  ->  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  =  ( ( 1  /  ( 2 ^ j ) )  x.  ( f `  j
) ) )
76cbvsumv 11705 . . . . 5  |-  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  =  sum_ j  e.  NN  (
( 1  /  (
2 ^ j ) )  x.  ( f `
 j ) )
82, 7trilpolemcl 16013 . . . . . 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 8089 . . . . . 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 4048 . . . . . . . 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 2212 . . . . . . . 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 4049 . . . . . . . 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 1324 . . . . . . 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 4049 . . . . . . . 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 2215 . . . . . . . 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 4048 . . . . . . . 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 1324 . . . . . . 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 2891 . . . . . 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 1249 . . . . 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 16018 . . . 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 2579 . . 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 9044 . . . 4  |-  NN  e.  _V
24 isomninn 16007 . . . 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 10581 . . 3  |-  NN  ~~  om
28 enomni 7243 . . 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 710    \/ w3o 980    = wceq 1373    e. wcel 2176   A.wral 2484   E.wrex 2485   _Vcvv 2772   {cpr 3634   class class class wbr 4045   omcom 4639   -->wf 5268   ` cfv 5272  (class class class)co 5946    ^m cmap 6737    ~~ cen 6827  Omnicomni 7238   RRcr 7926   0cc0 7927   1c1 7928    x. cmul 7932    < clt 8109    / cdiv 8747   NNcn 9038   2c2 9089   ^cexp 10685   sum_csu 11697
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 615  ax-in2 616  ax-io 711  ax-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-10 1528  ax-11 1529  ax-i12 1530  ax-bndl 1532  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-13 2178  ax-14 2179  ax-ext 2187  ax-coll 4160  ax-sep 4163  ax-nul 4171  ax-pow 4219  ax-pr 4254  ax-un 4481  ax-setind 4586  ax-iinf 4637  ax-cnex 8018  ax-resscn 8019  ax-1cn 8020  ax-1re 8021  ax-icn 8022  ax-addcl 8023  ax-addrcl 8024  ax-mulcl 8025  ax-mulrcl 8026  ax-addcom 8027  ax-mulcom 8028  ax-addass 8029  ax-mulass 8030  ax-distr 8031  ax-i2m1 8032  ax-0lt1 8033  ax-1rid 8034  ax-0id 8035  ax-rnegex 8036  ax-precex 8037  ax-cnre 8038  ax-pre-ltirr 8039  ax-pre-ltwlin 8040  ax-pre-lttrn 8041  ax-pre-apti 8042  ax-pre-ltadd 8043  ax-pre-mulgt0 8044  ax-pre-mulext 8045  ax-arch 8046  ax-caucvg 8047
This theorem depends on definitions:  df-bi 117  df-dc 837  df-3or 982  df-3an 983  df-tru 1376  df-fal 1379  df-nf 1484  df-sb 1786  df-eu 2057  df-mo 2058  df-clab 2192  df-cleq 2198  df-clel 2201  df-nfc 2337  df-ne 2377  df-nel 2472  df-ral 2489  df-rex 2490  df-reu 2491  df-rmo 2492  df-rab 2493  df-v 2774  df-sbc 2999  df-csb 3094  df-dif 3168  df-un 3170  df-in 3172  df-ss 3179  df-nul 3461  df-if 3572  df-pw 3618  df-sn 3639  df-pr 3640  df-op 3642  df-uni 3851  df-int 3886  df-iun 3929  df-br 4046  df-opab 4107  df-mpt 4108  df-tr 4144  df-id 4341  df-po 4344  df-iso 4345  df-iord 4414  df-on 4416  df-ilim 4417  df-suc 4419  df-iom 4640  df-xp 4682  df-rel 4683  df-cnv 4684  df-co 4685  df-dm 4686  df-rn 4687  df-res 4688  df-ima 4689  df-iota 5233  df-fun 5274  df-fn 5275  df-f 5276  df-f1 5277  df-fo 5278  df-f1o 5279  df-fv 5280  df-isom 5281  df-riota 5901  df-ov 5949  df-oprab 5950  df-mpo 5951  df-1st 6228  df-2nd 6229  df-recs 6393  df-irdg 6458  df-frec 6479  df-1o 6504  df-2o 6505  df-oadd 6508  df-er 6622  df-map 6739  df-en 6830  df-dom 6831  df-fin 6832  df-omni 7239  df-pnf 8111  df-mnf 8112  df-xr 8113  df-ltxr 8114  df-le 8115  df-sub 8247  df-neg 8248  df-reap 8650  df-ap 8657  df-div 8748  df-inn 9039  df-2 9097  df-3 9098  df-4 9099  df-n0 9298  df-z 9375  df-uz 9651  df-q 9743  df-rp 9778  df-ico 10018  df-fz 10133  df-fzo 10267  df-seqfrec 10595  df-exp 10686  df-ihash 10923  df-cj 11186  df-re 11187  df-im 11188  df-rsqrt 11342  df-abs 11343  df-clim 11623  df-sumdc 11698
This theorem is referenced by: (None)
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