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Unknot

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It can be difficult to find a way to untangle string even though the fact it started out untangled proves the task is possible. Thistlethwaite and Ochiai provided many examples of diagrams of unknots that have no obvious way to simplify them, requiring one to temporarily increase the diagram's
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While rope is generally not in the form of a closed loop, sometimes there is a canonical way to imagine the ends being joined together. From this point of view, many useful practical knots are actually the unknot, including those that can be tied in a
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is a particular unknotted linkage that cannot be reconfigured into a flat convex polygon. Like crossing number, a linkage might need to be made more complex by subdividing its segments before it can be simplified.
600: 617:(both of which have 11 crossings) have the same Alexander and Conway polynomials as the unknot. It is an open problem whether any non-trivial knot has the same Jones polynomial as the unknot. 430:
detect the unknot, but these are not known to be efficiently computable for this purpose. It is not known whether the Jones polynomial or
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is the minimal number of segments needed to represent a knot as a linkage, and a
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Deciding if a particular knot is the unknot was a major driving force behind
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The unknot is the only knot that is the boundary of an embedded
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tied into it, unknotted. To a knot theorist, an unknot is any
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Similarly, the unknot is the 319:Two simple diagrams of the unknot 1498:Non-tricolorable knots and links 1434: 1423: 1422: 467: 452: 20: 1468:Non-alternating knots and links 605:No other knot with 10 or fewer 573: 551: 31:needs additional citations for 1289:Dowker–Thistlethwaite notation 701: 583: 577: 561: 555: 539: 533: 1: 757:. Accessed: May 7, 2013. 668: 507: 726:(2): 301–306. Archived from 325:mathematical theory of knots 7: 643: 520:of the unknot are trivial: 514:Alexander–Conway polynomial 437: 118:Loop seen as a trivial knot 10: 1519: 392: 1418: 1322: 1279:Alexander–Briggs notation 1266: 1101: 1003: 968: 826: 290: 285: 270: 260: 247: 237: 227: 217: 207: 197: 187: 177: 167: 157: 147: 137: 128: 123: 491:can be represented as a 1478:Fibered knots and links 1370:List of knots and links 918:Kinoshita–Terasaka knot 611:Kinoshita–Terasaka knot 474:One of Ochiai's unknots 434:can detect the unknot. 596: 432:finite type invariants 320: 1488:Slice knots and links 1483:Prime knots and links 1473:Torus knots and links 1160:Finite type invariant 597: 318: 527: 405:recognize the unknot 381:with respect to the 40:improve this article 1330:Alexander's theorem 424:knot Floer homology 763:Weisstein, Eric W. 709:Godfried Toussaint 650:Knot (mathematics) 592: 395:Unknotting problem 389:Unknotting problem 348:topological circle 321: 1450: 1449: 1304:Reidemeister move 1170:Khovanov homology 1165:Hyperbolic volume 662:Unknotting number 428:Khovanov homology 422:It is known that 313: 312: 308:fully amphichiral 116: 115: 108: 90: 1510: 1438: 1437: 1426: 1425: 1390:Tait conjectures 1093: 1092: 1078: 1077: 1063: 1062: 955: 954: 940: 939: 924:(−2,3,7) pretzel 804: 797: 790: 781: 780: 776: 775: 735: 734: 732: 717: 705: 699: 698: 696: 695: 686:. Archived from 679: 601: 599: 598: 593: 518:Jones polynomial 471: 456: 379:identity element 356:ambient isotopic 133: 121: 120: 111: 104: 100: 97: 91: 89: 48: 24: 16: 1518: 1517: 1513: 1512: 1511: 1509: 1508: 1507: 1453: 1452: 1451: 1446: 1414: 1318: 1284:Conway notation 1268: 1262: 1249:Tricolorability 1097: 1091: 1088: 1087: 1086: 1076: 1073: 1072: 1071: 1061: 1058: 1057: 1056: 1048: 1038: 1028: 1018: 999: 978:Composite knots 964: 953: 950: 949: 948: 945:Borromean rings 938: 935: 934: 933: 907: 897: 887: 877: 869: 861: 851: 841: 822: 808: 744: 739: 738: 730: 715: 706: 702: 693: 691: 684:"Knotty topics" 682:Volker Schatz. 680: 676: 671: 646: 630:knot complement 624:is an infinite 528: 525: 524: 510: 475: 472: 463: 457: 445:crossing number 440: 401:knot invariants 397: 391: 364:standard unknot 280: 262:Dowker notation 256: 239:Conway notation 119: 112: 101: 95: 92: 49: 47: 37: 25: 12: 11: 5: 1516: 1506: 1505: 1500: 1495: 1490: 1485: 1480: 1475: 1470: 1465: 1448: 1447: 1445: 1444: 1432: 1419: 1416: 1415: 1413: 1412: 1410:Surgery theory 1407: 1402: 1397: 1392: 1387: 1382: 1377: 1372: 1367: 1362: 1357: 1352: 1347: 1342: 1337: 1332: 1326: 1324: 1320: 1319: 1317: 1316: 1311: 1309:Skein relation 1306: 1301: 1296: 1291: 1286: 1281: 1275: 1273: 1264: 1263: 1261: 1260: 1254:Unknotting no. 1251: 1246: 1241: 1240: 1239: 1229: 1224: 1223: 1222: 1217: 1212: 1207: 1202: 1192: 1187: 1182: 1177: 1172: 1167: 1162: 1157: 1152: 1147: 1146: 1145: 1135: 1130: 1129: 1128: 1118: 1113: 1107: 1105: 1099: 1098: 1096: 1095: 1089: 1080: 1074: 1065: 1059: 1050: 1046: 1040: 1036: 1030: 1026: 1020: 1016: 1009: 1007: 1001: 1000: 998: 997: 992: 991: 990: 985: 974: 972: 966: 965: 963: 962: 957: 951: 942: 936: 927: 921: 915: 909: 905: 899: 895: 889: 885: 879: 875: 871: 867: 863: 859: 853: 849: 843: 839: 832: 830: 824: 823: 807: 806: 799: 792: 784: 778: 777: 758: 754:The Knot Atlas 743: 742:External links 740: 737: 736: 733:on 2003-05-12. 700: 673: 672: 670: 667: 666: 665: 659: 653: 645: 642: 603: 602: 591: 588: 585: 582: 579: 576: 572: 569: 566: 563: 560: 557: 554: 550: 547: 544: 541: 538: 535: 532: 509: 506: 477: 476: 473: 466: 464: 460:Thistlethwaite 458: 451: 439: 436: 393:Main article: 390: 387: 311: 310: 288: 287: 283: 282: 278: 274: 268: 267: 264: 258: 257: 254: 251: 245: 244: 241: 235: 234: 231: 229:Unknotting no. 225: 224: 221: 215: 214: 211: 205: 204: 201: 195: 194: 191: 185: 184: 181: 175: 174: 171: 165: 164: 161: 155: 154: 151: 145: 144: 139: 135: 134: 126: 125: 117: 114: 113: 28: 26: 19: 9: 6: 4: 3: 2: 1515: 1504: 1501: 1499: 1496: 1494: 1491: 1489: 1486: 1484: 1481: 1479: 1476: 1474: 1471: 1469: 1466: 1464: 1461: 1460: 1458: 1443: 1442: 1433: 1431: 1430: 1421: 1420: 1417: 1411: 1408: 1406: 1403: 1401: 1398: 1396: 1393: 1391: 1388: 1386: 1383: 1381: 1378: 1376: 1373: 1371: 1368: 1366: 1363: 1361: 1358: 1356: 1353: 1351: 1348: 1346: 1345:Conway sphere 1343: 1341: 1338: 1336: 1333: 1331: 1328: 1327: 1325: 1321: 1315: 1312: 1310: 1307: 1305: 1302: 1300: 1297: 1295: 1292: 1290: 1287: 1285: 1282: 1280: 1277: 1276: 1274: 1272: 1265: 1259: 1255: 1252: 1250: 1247: 1245: 1242: 1238: 1235: 1234: 1233: 1230: 1228: 1225: 1221: 1218: 1216: 1213: 1211: 1208: 1206: 1203: 1201: 1198: 1197: 1196: 1193: 1191: 1188: 1186: 1183: 1181: 1178: 1176: 1173: 1171: 1168: 1166: 1163: 1161: 1158: 1156: 1153: 1151: 1148: 1144: 1141: 1140: 1139: 1136: 1134: 1131: 1127: 1124: 1123: 1122: 1119: 1117: 1116:Arf invariant 1114: 1112: 1109: 1108: 1106: 1104: 1100: 1084: 1081: 1069: 1066: 1054: 1051: 1044: 1041: 1034: 1031: 1024: 1021: 1014: 1011: 1010: 1008: 1006: 1002: 996: 993: 989: 986: 984: 981: 980: 979: 976: 975: 973: 971: 967: 961: 958: 946: 943: 931: 928: 925: 922: 919: 916: 913: 910: 903: 900: 893: 890: 883: 880: 878: 872: 870: 864: 857: 854: 847: 844: 837: 834: 833: 831: 829: 825: 820: 816: 812: 805: 800: 798: 793: 791: 786: 785: 782: 773: 772: 767: 764: 759: 756: 755: 750: 746: 745: 729: 725: 721: 714: 710: 704: 690:on 2011-07-17 689: 685: 678: 674: 663: 660: 657: 654: 651: 648: 647: 641: 639: 635: 631: 627: 623: 618: 616: 612: 608: 589: 586: 580: 574: 570: 567: 564: 558: 548: 545: 542: 536: 523: 522: 521: 519: 515: 505: 502: 498: 494: 490: 485: 483: 470: 465: 461: 455: 450: 449: 448: 446: 435: 433: 429: 425: 420: 418: 414: 410: 406: 402: 396: 386: 384: 380: 376: 375:Seifert genus 372: 367: 365: 361: 357: 353: 349: 346: 342: 338: 334: 330: 326: 317: 309: 305: 301: 297: 293: 289: 284: 281: 275: 273: 269: 265: 263: 259: 252: 250: 246: 242: 240: 236: 232: 230: 226: 222: 220: 216: 212: 210: 206: 202: 200: 196: 192: 190: 186: 182: 180: 176: 172: 170: 166: 162: 160: 156: 152: 150: 149:Arf invariant 146: 143: 140: 136: 132: 127: 122: 110: 107: 99: 96:November 2021 88: 85: 81: 78: 74: 71: 67: 64: 60: 57: –  56: 52: 51:Find sources: 45: 41: 35: 34: 29:This article 27: 23: 18: 17: 1439: 1427: 1355:Double torus 1340:Braid theory 1155:Crossing no. 1150:Crosscap no. 1012: 836:Figure-eight 769: 752: 728:the original 723: 719: 703: 692:. Retrieved 688:the original 677: 634:homeomorphic 626:cyclic group 619: 604: 511: 501:stuck unknot 497:stick number 486: 478: 441: 421: 409:knot diagram 398: 368: 363: 337:trivial knot 336: 332: 328: 322: 249:A–B notation 179:Crossing no. 102: 93: 83: 76: 69: 62: 50: 38:Please help 33:verification 30: 1463:Knot theory 1190:Linking no. 1111:Alternating 912:Conway knot 892:Carrick mat 846:Three-twist 811:Knot theory 638:solid torus 615:Conway knot 385:operation. 199:Linking no. 138:Common name 1457:Categories 1350:Complement 1314:Tabulation 1271:operations 1195:Polynomial 1185:Link group 1180:Knot group 1143:Invertible 1121:Bridge no. 1103:Invariants 1033:Cinquefoil 902:Perko pair 828:Hyperbolic 694:2007-04-23 669:References 628:, and its 622:knot group 508:Invariants 219:Tunnel no. 169:Bridge no. 66:newspapers 1244:Stick no. 1200:Alexander 1138:Chirality 1083:Solomon's 1043:Septafoil 970:Satellite 930:Whitehead 856:Stevedore 771:MathWorld 607:crossings 553:∇ 531:Δ 489:tame knot 209:Stick no. 159:Braid no. 1429:Category 1299:Mutation 1267:Notation 1220:Kauffman 1133:Brunnian 1126:2-bridge 995:Knot sum 926:(12n242) 766:"Unknot" 711:(2001). 644:See also 438:Examples 383:knot sum 354:that is 352:3-sphere 345:embedded 333:not knot 55:"Unknot" 1503:Circles 1441:Commons 1360:Fibered 1258:problem 1227:Pretzel 1205:Bracket 1023:Trefoil 960:L10a140 920:(11n42) 914:(11n34) 882:Endless 493:linkage 350:in the 323:In the 296:fibered 80:scholar 1405:Writhe 1375:Ribbon 1210:HOMFLY 1053:Unlink 1013:Unknot 988:Square 983:Granny 749:Unknot 656:Unlink 487:Every 462:unknot 362:, the 360:circle 329:unknot 327:, the 306:, 302:, 298:, 294:, 142:Circle 124:Unknot 82:  75:  68:  61:  53:  1395:Twist 1380:Slice 1335:Berge 1323:Other 1294:Flype 1232:Prime 1215:Jones 1175:Genus 1005:Torus 819:links 815:knots 731:(PDF) 716:(PDF) 636:to a 482:bight 417:co-NP 335:, or 304:slice 300:prime 292:torus 286:Other 189:Genus 87:JSTOR 73:books 1400:Wild 1365:Knot 1269:and 1256:and 1237:list 1068:Hopf 817:and 613:and 516:and 512:The 426:and 415:and 371:disk 341:knot 272:Next 59:news 1385:Sum 906:161 904:(10 751:", 632:is 42:by 1459:: 1085:(4 1070:(2 1055:(0 1045:(7 1035:(5 1025:(3 1015:(0 947:(6 932:(5 896:18 894:(8 884:(7 858:(6 848:(5 838:(4 768:. 724:42 722:. 718:. 640:. 590:1. 484:. 447:. 419:. 413:NP 366:. 331:, 1094:) 1090:1 1079:) 1075:1 1064:) 1060:1 1049:) 1047:1 1039:) 1037:1 1029:) 1027:1 1019:) 1017:1 956:) 952:2 941:) 937:1 908:) 898:) 888:) 886:4 876:3 874:6 868:2 866:6 862:) 860:1 852:) 850:2 842:) 840:1 821:) 813:( 803:e 796:t 789:v 774:. 747:" 697:. 587:= 584:) 581:q 578:( 575:V 571:, 568:1 565:= 562:) 559:z 556:( 549:, 546:1 543:= 540:) 537:t 534:( 279:1 277:3 266:- 255:1 253:0 243:- 233:0 223:0 213:3 203:0 193:0 183:0 173:0 163:1 153:0 109:) 103:( 98:) 94:( 84:· 77:· 70:· 63:· 36:.

Index


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"Unknot"
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Circle
Arf invariant
Braid no.
Bridge no.
Crossing no.
Genus
Linking no.
Stick no.
Tunnel no.
Unknotting no.
Conway notation
A–B notation
Dowker notation
Next
31
torus
fibered
prime

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