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Truth-table reduction

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is one where the reduction uses the oracle answers as a basis for further computation, which may depend on the given answers but may not ask further questions of the oracle. It is so named because it weakens the constraints placed on a truth-table reduction, and provides a weaker equivalence
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classification; as such, a "weak truth-table reduction" can actually be more powerful than a truth-table reduction as a "tool", and perform a reduction that is not performable by truth table. Equivalently, a weak truth-table reduction is a Turing reduction for which the
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during the computation; it may adaptively determine which questions it asks based upon answers to previous questions. In contrast, a truth-table reduction or a weak truth-table reduction must present all of its (finitely many)
160:, and strictly weaker. (That is, not every Turing reduction between sets can be performed by a truth-table reduction, but every truth-table reduction can be performed by a Turing reduction.) A Turing reduction from a set 421:
or in other words, one-one reducibility implies many-one reducibility, which implies truth-table reducibility, which in turn implies weak truth-table reducibility, which in turn implies Turing reducibility.
302: 655: 557: 615: 466: 675: 585: 518: 486: 151: 123: 103: 83: 63: 762: 786: 706: 698: 781: 410:{\displaystyle A\leq _{1}B\Rightarrow A\leq _{m}B\Rightarrow A\leq _{tt}B\Rightarrow A\leq _{wtt}B\Rightarrow A\leq _{T}B} 755: 178: 185:(a truth table) that, when given the answers to the queries, will produce the final answer of the reduction. 748: 624: 526: 39: 590: 31: 686: 296:). Considering also one-one reducibility, many-one reducibility and weak truth-table reducibility, 243: 564: 728: 444: 702: 694: 660: 570: 503: 471: 239: 182: 157: 126: 43: 732: 136: 108: 88: 68: 48: 197: 775: 181:
queries at the same time. In a truth-table reduction, the reduction also gives a
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is a total computable functional. To build the truth-table for computing
468:. The forward direction is trivial and for the reverse direction suppose 720: 677:. The forward direction fails for weak truth-table reducibility. 250:(bT) reductions rather than as weak truth-table (wtt) reductions. 621:
it is a simple matter to find the unique truth-table that gives
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by asking questions about the membership of various elements in
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The Theory of Recursive Functions and Effective Computability
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As every truth-table reduction is a Turing reduction, if
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You can help Knowledge by 429:is truth-table reducible to 281:is also Turing reducible to 262:is truth-table reducible to 461:{\displaystyle 2^{\omega }} 229:Weak truth-table reductions 803: 714: 441:via a total functional on 235:weak truth-table reduction 787:Mathematical logic stubs 85:. To solve a problem in 670:{\displaystyle \sigma } 580:{\displaystyle \Gamma } 513:{\displaystyle \sigma } 481:{\displaystyle \Gamma } 437:is Turing reducible to 782:Reduction (complexity) 731:-related article is a 671: 651: 611: 581: 553: 514: 482: 462: 411: 147: 119: 99: 79: 65:to a decision problem 59: 672: 652: 612: 582: 554: 515: 483: 463: 412: 148: 120: 100: 80: 60: 36:truth-table reduction 661: 625: 591: 571: 559:converges. Such an 527: 504: 472: 445: 303: 137: 109: 89: 69: 49: 32:computability theory 244:computable function 729:mathematical logic 667: 647: 607: 577: 549: 510: 478: 458: 407: 208:. You can help by 143: 115: 95: 75: 55: 744: 743: 617:. Given such an 226: 225: 158:Turing reductions 146:{\displaystyle B} 118:{\displaystyle A} 98:{\displaystyle A} 78:{\displaystyle B} 58:{\displaystyle A} 16:(Redirected from 794: 765: 758: 751: 723: 716: 676: 674: 673: 668: 657:when applied to 656: 654: 653: 648: 637: 636: 616: 614: 613: 608: 606: 605: 586: 584: 583: 578: 558: 556: 555: 550: 539: 538: 519: 517: 516: 511: 487: 485: 484: 479: 467: 465: 464: 459: 457: 456: 416: 414: 413: 408: 403: 402: 384: 383: 359: 358: 337: 336: 318: 317: 221: 218: 200: 193: 152: 150: 149: 144: 124: 122: 121: 116: 104: 102: 101: 96: 84: 82: 81: 76: 64: 62: 61: 56: 44:decision problem 21: 802: 801: 797: 796: 795: 793: 792: 791: 772: 771: 770: 769: 712: 683: 659: 658: 628: 623: 622: 594: 589: 588: 569: 568: 530: 525: 524: 502: 501: 470: 469: 448: 443: 442: 433:if and only if 394: 369: 347: 328: 309: 301: 300: 292: 273: 256: 231: 222: 216: 213: 206:needs expansion 191: 183:boolean formula 135: 134: 127:boolean formula 107: 106: 87: 86: 67: 66: 47: 46: 28: 23: 22: 15: 12: 11: 5: 800: 798: 790: 789: 784: 774: 773: 768: 767: 760: 753: 745: 742: 741: 724: 710: 709: 687:H. Rogers, Jr. 682: 679: 666: 646: 643: 640: 635: 631: 604: 601: 597: 576: 563:must exist by 548: 545: 542: 537: 533: 509: 477: 455: 451: 419: 418: 406: 401: 397: 393: 390: 387: 382: 379: 376: 372: 368: 365: 362: 357: 354: 350: 346: 343: 340: 335: 331: 327: 324: 321: 316: 312: 308: 290: 271: 255: 252: 248:bounded Turing 230: 227: 224: 223: 203: 201: 190: 187: 142: 114: 94: 74: 54: 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 799: 788: 785: 783: 780: 779: 777: 766: 761: 759: 754: 752: 747: 746: 740: 738: 734: 730: 725: 722: 718: 713: 708: 707:0-07-053522-1 704: 701:(paperback), 700: 699:0-262-68052-1 696: 692: 688: 685: 684: 680: 678: 664: 641: 633: 620: 602: 599: 595: 566: 565:Kőnig's lemma 562: 543: 535: 523: 507: 499: 495: 491: 453: 449: 440: 436: 432: 428: 425:Furthermore, 423: 404: 399: 395: 391: 385: 380: 377: 374: 370: 366: 360: 355: 352: 348: 344: 338: 333: 329: 325: 319: 314: 310: 306: 299: 298: 297: 295: 288: 284: 280: 276: 269: 265: 261: 253: 251: 249: 245: 241: 236: 228: 220: 211: 207: 204:This section 202: 199: 195: 194: 188: 186: 184: 180: 175: 171: 167: 163: 159: 154: 140: 132: 128: 112: 92: 72: 52: 45: 41: 38:is a type of 37: 33: 19: 737:expanding it 726: 711: 690: 618: 560: 521: 497: 493: 489: 438: 434: 430: 426: 424: 420: 293: 286: 282: 278: 274: 267: 263: 259: 257: 247: 234: 232: 214: 210:adding to it 205: 173: 169: 165: 161: 155: 35: 29: 18:Tt-reduction 131:truth table 776:Categories 681:References 520:of length 254:Properties 217:April 2024 189:Definition 665:σ 634:σ 630:Γ 603:ω 575:Γ 536:σ 532:Γ 508:σ 476:Γ 454:ω 396:≤ 389:⇒ 371:≤ 364:⇒ 349:≤ 342:⇒ 330:≤ 323:⇒ 311:≤ 164:to a set 40:reduction 689:, 1967. 277:), then 289:≤ 270:≤ 42:from a 705:  697:  567:since 179:oracle 727:This 125:as a 733:stub 703:ISBN 695:ISBN 600:< 240:use 212:. 129:or 30:In 778:: 272:tt 233:A 153:. 34:a 764:e 757:t 750:v 739:. 645:) 642:n 639:( 619:m 596:2 561:m 547:) 544:n 541:( 522:m 498:m 494:n 492:( 490:A 450:2 439:B 435:A 431:B 427:A 417:, 405:B 400:T 392:A 386:B 381:t 378:t 375:w 367:A 361:B 356:t 353:t 345:A 339:B 334:m 326:A 320:B 315:1 307:A 294:B 291:T 287:A 285:( 283:B 279:A 275:B 268:A 266:( 264:B 260:A 219:) 215:( 174:A 170:B 166:A 162:B 141:B 113:A 93:A 73:B 53:A 20:)

Index

Tt-reduction
computability theory
reduction
decision problem
boolean formula
truth table
Turing reductions
oracle
boolean formula

adding to it
use
computable function
Kőnig's lemma
H. Rogers, Jr.
ISBN
0-262-68052-1
ISBN
0-07-053522-1
Stub icon
mathematical logic
stub
expanding it
v
t
e
Categories
Reduction (complexity)
Mathematical logic stubs

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