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Theorem trilpo 17190
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 17188 (which means the sequence contains a zero), trilpolemeq1 17187 (which means the sequence is all ones), and trilpolemgt1 17186 (which is not possible).

Equivalent ways to state real number trichotomy (sometimes called "analytic LPO") include decidability of real number apartness (see triap 17176) or that the real numbers are a discrete field (see trirec0 17191).

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 10685 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 6944 . . . . . 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 6093 . . . . . . . 8  |-  ( i  =  j  ->  (
2 ^ i )  =  ( 2 ^ j ) )
43oveq2d 6101 . . . . . . 7  |-  ( i  =  j  ->  (
1  /  ( 2 ^ i ) )  =  ( 1  / 
( 2 ^ j
) ) )
5 fveq2 5695 . . . . . . 7  |-  ( i  =  j  ->  (
f `  i )  =  ( f `  j ) )
64, 5oveq12d 6103 . . . . . 6  |-  ( i  =  j  ->  (
( 1  /  (
2 ^ i ) )  x.  ( f `
 i ) )  =  ( ( 1  /  ( 2 ^ j ) )  x.  ( f `  j
) ) )
76cbvsumv 12143 . . . . 5  |-  sum_ i  e.  NN  ( ( 1  /  ( 2 ^ i ) )  x.  ( f `  i
) )  =  sum_ j  e.  NN  (
( 1  /  (
2 ^ j ) )  x.  ( f `
 j ) )
82, 7trilpolemcl 17184 . . . . . 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 8341 . . . . . 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 4133 . . . . . . . 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 2245 . . . . . . . 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 4134 . . . . . . . 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 1352 . . . . . . 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 4134 . . . . . . . 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 2248 . . . . . . . 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 4133 . . . . . . . 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 1352 . . . . . . 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 2944 . . . . . 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 1277 . . . . 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 17189 . . . 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 2623 . . 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 9312 . . . 4  |-  NN  e.  _V
24 isomninn 17178 . . . 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 10884 . . 3  |-  NN  ~~  om
28 enomni 7479 . . 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
This proof depends on syntax axioms:    -> wi 4    /\ wa 104    <-> wb 105    \/ wo 720    \/ w3o 1008    = wceq 1402    e. wcel 2209   A.wral 2528   E.wrex 2529   _Vcvv 2821   {cpr 3710   class class class wbr 4130   omcom 4737   -->wf 5373   ` cfv 5377  (class class class)co 6085    ^m cmap 6922    ~~ cen 7020  Omnicomni 7474   RRcr 8178   0cc0 8179   1c1 8180    x. cmul 8184    < clt 8360    / cdiv 9004   NNcn 9306   2c2 9357   ^cexp 10988   sum_csu 12135
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-14 2212  ax-ext 2220  ax-coll 4246  ax-sep 4249  ax-nul 4259  ax-pow 4311  ax-pr 4346  ax-un 4578  ax-setind 4684  ax-iinf 4735  ax-cnex 8270  ax-resscn 8271  ax-1cn 8272  ax-1re 8273  ax-icn 8274  ax-addcl 8275  ax-addrcl 8276  ax-mulcl 8277  ax-mulrcl 8278  ax-addcom 8279  ax-mulcom 8280  ax-addass 8281  ax-mulass 8282  ax-distr 8283  ax-i2m1 8284  ax-0lt1 8285  ax-1rid 8286  ax-0id 8287  ax-rnegex 8288  ax-precex 8289  ax-cnre 8290  ax-pre-ltirr 8291  ax-pre-ltwlin 8292  ax-pre-lttrn 8293  ax-pre-apti 8294  ax-pre-ltadd 8295  ax-pre-mulgt0 8296  ax-pre-mulext 8297  ax-arch 8298  ax-caucvg 8299
This proof depends on definitions:  df-bi 117  df-dc 847  df-3or 1010  df-3an 1011  df-tru 1405  df-fal 1408  df-nf 1514  df-sb 1816  df-eu 2089  df-mo 2090  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-nel 2516  df-ral 2533  df-rex 2534  df-reu 2535  df-rmo 2536  df-rab 2537  df-v 2823  df-sbc 3052  df-csb 3148  df-dif 3222  df-un 3224  df-in 3226  df-ss 3233  df-nul 3521  df-if 3639  df-pw 3690  df-sn 3715  df-pr 3716  df-op 3718  df-uni 3936  df-int 3971  df-iun 4014  df-br 4131  df-opab 4193  df-mpt 4194  df-tr 4230  df-id 4438  df-po 4441  df-iso 4442  df-iord 4511  df-on 4513  df-ilim 4514  df-suc 4516  df-iom 4738  df-xp 4780  df-rel 4781  df-cnv 4782  df-co 4783  df-dm 4784  df-rn 4785  df-res 4786  df-ima 4787  df-iota 5337  df-fun 5379  df-fn 5380  df-f 5381  df-f1 5382  df-fo 5383  df-f1o 5384  df-fv 5385  df-isom 5386  df-riota 6038  df-ov 6088  df-oprab 6089  df-mpo 6090  df-1st 6374  df-2nd 6375  df-recs 6576  df-irdg 6641  df-frec 6662  df-1o 6687  df-2o 6688  df-oadd 6691  df-er 6807  df-map 6924  df-en 7023  df-dom 7024  df-fin 7025  df-omni 7475  df-pnf 8362  df-mnf 8363  df-xr 8364  df-ltxr 8365  df-le 8366  df-sub 8500  df-neg 8501  df-reap 8905  df-ap 8912  df-div 9005  df-inn 9307  df-2 9365  df-3 9366  df-4 9367  df-n0 9568  df-z 9649  df-uz 9931  df-q 10029  df-rp 10065  df-ico 10306  df-fz 10422  df-fzo 10560  df-seqfrec 10898  df-exp 10989  df-ihash 11229  df-cj 11621  df-re 11622  df-im 11623  df-rsqrt 11778  df-abs 11779  df-clim 12061  df-sumdc 12136
This theorem is used by: (None)
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