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Tarski's exponential function problem

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implies such a procedure exists, and hence gave a conditional solution to Tarski's problem. Schanuel's conjecture deals with all complex numbers so would be expected to be a stronger result than the decidability of
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for the decidability of the theory. In their paper, Macintyre and Wilkie showed that an equivalent result to the decidability of
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is what they dubbed the weak Schanuel's conjecture. This conjecture states that there is an effective procedure that, given
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On the Decidability of the Real Exponential Field, in: Kreiseliana: about and around Georg Kreisel
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The problem can be reduced to finding an effective procedure for determining whether any given
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He then asked whether this was still the case if one added a unary function
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theory of the real numbers (without the exponential function) is decidable
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Even the real version of Schanuel's conjecture is not a
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there is an effective procedure for determining whether
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Wellesley, MA: A K Peters. pp. 441–467. 1059:"Model theory of the real exponential function" 425: 256:{\displaystyle \mathbb {R} \models \varphi .} 8: 286:to the language that was interpreted as the 137:{\displaystyle L_{\text{or}}=(+,-,<,0,1)} 720:{\displaystyle \alpha \in \mathbb {R} ^{n}} 1018: 1010: 993: 991: 956: 921: 916: 895: 890: 877: 858: 845: 821: 816: 795: 790: 777: 758: 745: 739: 711: 707: 706: 697: 670: 651: 639: 613: 586: 567: 561: 541: 515: 491: 487: 486: 474: 446: 442: 441: 438: 408: 404: 403: 400: 381: 380: 378: 358: 325: 321: 320: 317: 298: 297: 295: 271: 240: 239: 237: 214: 193: 187: 165: 164: 153: 92: 86: 64: 63: 61: 1049: 685:{\displaystyle n,f_{1},\dots ,f_{n},g} 22:Tarski's exponential function problem 7: 601:{\displaystyle f_{1},\dots ,f_{n},g} 556:variables with integer coefficients 455:{\displaystyle \mathbb {R} _{\exp }} 334:{\displaystyle \mathbb {R} _{\exp }} 182:, is decidable. That is, given any 78:is a structure over the language of 373:variables and with coefficients in 345:Conditional and equivalent results 14: 1147:Unsolved problems in mathematics 417:{\displaystyle \mathbb {R} ^{n}} 536:and exponential polynomials in 1011: 1007: 1001: 994: 967: 961: 929: 851: 829: 751: 497: 482: 169: 161: 131: 101: 44:had previously shown that the 1: 1065:. Heidelberg: Springer-Verlag 426:Macintyre & Wilkie (1996) 202:{\displaystyle L_{\text{or}}} 979:{\displaystyle g(\alpha )=0} 388:{\displaystyle \mathbb {Z} } 305:{\displaystyle \mathbb {R} } 71:{\displaystyle \mathbb {R} } 1063:Encyclopedia of Mathematics 627:{\displaystyle \eta \geq 1} 1163: 222:{\displaystyle \varphi } 1092:Oddifreddi, Piergiorgio 731:solution of the system 529:{\displaystyle n\geq 1} 312:, to get the structure 56:The ordered real field 1034: 980: 942: 721: 686: 628: 608:, produces an integer 602: 550: 530: 504: 456: 418: 389: 367: 351:exponential polynomial 335: 306: 280: 257: 223: 203: 176: 138: 72: 1035: 981: 943: 722: 687: 629: 603: 551: 531: 505: 457: 430:Schanuel's conjecture 419: 390: 368: 336: 307: 281: 279:{\displaystyle \exp } 258: 224: 204: 177: 139: 73: 990: 955: 738: 696: 638: 612: 560: 540: 514: 473: 437: 399: 377: 357: 316: 294: 288:exponential function 270: 236: 213: 186: 152: 85: 60: 34:exponential function 692:, and such that if 467:necessary condition 1030: 1028: 976: 938: 717: 682: 624: 598: 546: 526: 500: 452: 414: 395:has a solution in 385: 363: 331: 302: 276: 253: 219: 199: 172: 134: 68: 32:together with the 1027: 549:{\displaystyle n} 366:{\displaystyle n} 196: 95: 24:asks whether the 1154: 1126: 1125: 1084:Macintyre, Angus 1080: 1074: 1073: 1071: 1070: 1054: 1039: 1037: 1036: 1031: 1029: 1020: 1014: 997: 985: 983: 982: 977: 947: 945: 944: 939: 928: 927: 926: 925: 902: 901: 900: 899: 882: 881: 863: 862: 850: 849: 828: 827: 826: 825: 802: 801: 800: 799: 782: 781: 763: 762: 750: 749: 726: 724: 723: 718: 716: 715: 710: 691: 689: 688: 683: 675: 674: 656: 655: 634:that depends on 633: 631: 630: 625: 607: 605: 604: 599: 591: 590: 572: 571: 555: 553: 552: 547: 535: 533: 532: 527: 509: 507: 506: 501: 496: 495: 490: 461: 459: 458: 453: 451: 450: 445: 423: 421: 420: 415: 413: 412: 407: 394: 392: 391: 386: 384: 372: 370: 369: 364: 340: 338: 337: 332: 330: 329: 324: 311: 309: 308: 303: 301: 285: 283: 282: 277: 262: 260: 259: 254: 243: 228: 226: 225: 220: 208: 206: 205: 200: 198: 197: 194: 181: 179: 178: 173: 168: 143: 141: 140: 135: 97: 96: 93: 77: 75: 74: 69: 67: 1162: 1161: 1157: 1156: 1155: 1153: 1152: 1151: 1132: 1131: 1130: 1129: 1106: 1082: 1081: 1077: 1068: 1066: 1056: 1055: 1051: 1046: 988: 987: 953: 952: 917: 912: 891: 886: 873: 854: 841: 817: 812: 791: 786: 773: 754: 741: 736: 735: 705: 694: 693: 666: 647: 636: 635: 610: 609: 582: 563: 558: 557: 538: 537: 512: 511: 485: 471: 470: 440: 435: 434: 402: 397: 396: 375: 374: 355: 354: 347: 319: 314: 313: 292: 291: 268: 267: 234: 233: 211: 210: 189: 184: 183: 150: 149: 88: 83: 82: 58: 57: 54: 12: 11: 5: 1160: 1158: 1150: 1149: 1144: 1134: 1133: 1128: 1127: 1104: 1075: 1048: 1047: 1045: 1042: 1026: 1023: 1017: 1013: 1009: 1006: 1003: 1000: 996: 975: 972: 969: 966: 963: 960: 949: 948: 937: 934: 931: 924: 920: 915: 911: 908: 905: 898: 894: 889: 885: 880: 876: 872: 869: 866: 861: 857: 853: 848: 844: 840: 837: 834: 831: 824: 820: 815: 811: 808: 805: 798: 794: 789: 785: 780: 776: 772: 769: 766: 761: 757: 753: 748: 744: 714: 709: 704: 701: 681: 678: 673: 669: 665: 662: 659: 654: 650: 646: 643: 623: 620: 617: 597: 594: 589: 585: 581: 578: 575: 570: 566: 545: 525: 522: 519: 499: 494: 489: 484: 481: 478: 449: 444: 411: 406: 383: 362: 346: 343: 328: 323: 300: 275: 264: 263: 252: 249: 246: 242: 218: 192: 171: 167: 163: 160: 157: 133: 130: 127: 124: 121: 118: 115: 112: 109: 106: 103: 100: 91: 66: 53: 50: 13: 10: 9: 6: 4: 3: 2: 1159: 1148: 1145: 1143: 1140: 1139: 1137: 1123: 1119: 1115: 1111: 1107: 1105:9781568810614 1101: 1097: 1093: 1089: 1085: 1079: 1076: 1064: 1060: 1057:Kuhlmann, S. 1053: 1050: 1043: 1041: 1024: 1021: 1015: 1004: 998: 973: 970: 964: 958: 935: 932: 922: 918: 913: 909: 906: 903: 896: 892: 887: 883: 878: 874: 870: 867: 864: 859: 855: 846: 842: 838: 835: 832: 822: 818: 813: 809: 806: 803: 796: 792: 787: 783: 778: 774: 770: 767: 764: 759: 755: 746: 742: 734: 733: 732: 730: 712: 702: 699: 679: 676: 671: 667: 663: 660: 657: 652: 648: 644: 641: 621: 618: 615: 595: 592: 587: 583: 579: 576: 573: 568: 564: 543: 523: 520: 517: 492: 479: 476: 468: 463: 447: 431: 427: 409: 360: 352: 344: 342: 326: 289: 273: 250: 247: 244: 232: 231: 230: 216: 190: 158: 155: 147: 128: 125: 122: 119: 116: 113: 110: 107: 104: 98: 89: 81: 80:ordered rings 51: 49: 47: 43: 42:Alfred Tarski 39: 35: 31: 27: 23: 19: 1142:Model theory 1095: 1088:Wilkie, Alex 1078: 1067:. Retrieved 1062: 1052: 951:then either 950: 729:non-singular 464: 428:showed that 348: 265: 55: 30:real numbers 21: 18:model theory 15: 52:The problem 1136:Categories 1122:0896.03012 1069:2024-08-07 1044:References 209:-sentence 146:real field 1025:η 1005:α 965:α 907:… 868:… 836:… 807:… 768:… 703:∈ 700:α 661:… 619:≥ 616:η 577:… 521:≥ 480:⁡ 248:φ 245:⊨ 217:φ 159:⁡ 111:− 38:decidable 1090:(1996). 1114:1435773 1094:(ed.). 28:of the 1120:  1112:  1102:  26:theory 727:is a 1100:ISBN 1016:> 117:< 1118:Zbl 986:or 493:exp 448:exp 424:. 353:in 327:exp 290:on 274:exp 36:is 16:In 1138:: 1116:. 1110:MR 1108:. 1086:; 1061:. 1040:. 477:Th 341:. 195:or 156:Th 148:, 94:or 48:. 40:. 20:, 1124:. 1072:. 1022:1 1012:| 1008:) 1002:( 999:g 995:| 974:0 971:= 968:) 962:( 959:g 936:0 933:= 930:) 923:n 919:x 914:e 910:, 904:, 897:1 893:x 888:e 884:, 879:n 875:x 871:, 865:, 860:1 856:x 852:( 847:n 843:f 839:= 833:= 830:) 823:n 819:x 814:e 810:, 804:, 797:1 793:x 788:e 784:, 779:n 775:x 771:, 765:, 760:1 756:x 752:( 747:1 743:f 713:n 708:R 680:g 677:, 672:n 668:f 664:, 658:, 653:1 649:f 645:, 642:n 622:1 596:g 593:, 588:n 584:f 580:, 574:, 569:1 565:f 544:n 524:1 518:n 498:) 488:R 483:( 443:R 410:n 405:R 382:Z 361:n 322:R 299:R 251:. 241:R 191:L 170:) 166:R 162:( 132:) 129:1 126:, 123:0 120:, 114:, 108:, 105:+ 102:( 99:= 90:L 65:R

Index

model theory
theory
real numbers
exponential function
decidable
Alfred Tarski
theory of the real numbers (without the exponential function) is decidable
ordered rings
real field
exponential function
exponential polynomial
Macintyre & Wilkie (1996)
Schanuel's conjecture
necessary condition
non-singular
"Model theory of the real exponential function"
Macintyre, Angus
Wilkie, Alex
Oddifreddi, Piergiorgio
ISBN
9781568810614
MR
1435773
Zbl
0896.03012
Categories
Model theory
Unsolved problems in mathematics

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