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Analyst's traveling salesman theorem

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when zooming in on almost all of its points. This suggests that testing us whether a set could be contained in a rectifiable curve must somehow incorporate information about how flat it is when one zooms in on its points at different scales.
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of finite length. Whereas the original traveling salesman problem asks for the shortest way to visit every vertex in a finite set with a discrete path, this analytical version may require the curve to visit infinitely many points.
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subset of the Euclidean plane. However, it may be necessary for such an arc to have infinite length, failing to meet the conditions of the analyst's traveling salesman theorem.
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gives general conditions under which a point set can be covered by the homeomorphic image of a curve. This is true, in particular, for every compact
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at almost all of its points, where in this case "almost all" means all but a subset whose one-dimensional
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Conversely (and substantially more difficult to prove), if Γ is a rectifiable curve, then
1208:(since in a metric space there isn't necessarily a notion of a cube or a straight line). 1266: 1136:, and in particular, implies the theorems of Jones and Okikiolu, where now the constant 908: 931: 883:{\displaystyle \beta (E)={\text{diam}}E+\sum _{Q\in \Delta }\beta _{E}(3Q)^{2}\ell (Q)} 504: 484: 413: 393: 341: 292: 272: 171: 49:
is zero. Accordingly, if a set is contained in a rectifiable curve, the set must look
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This discussion motivates the definition of the following quantity, for a plane set
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The Traveling Salesman Theorem was shown to hold in general Euclidean spaces by
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of positive measure. For this, he had to redefine the definition of the
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defined in a similar way as dyadic squares. In her proof, the constant
42: 1405: 1388: 1128:), Raanan Schul showed Traveling Salesman Theorem also holds for sets 1351: 1080: > 1, where Δ is now the collection of dyadic cubes in 1299:(1992). "Characterization of subsets of rectifiable curves in Rn". 161:{\displaystyle \beta _{E}(Q)={\frac {1}{\ell (Q)}}\inf\{\delta :{}} 1389:"Menger curvature and Lipschitz parametrizations in metric spaces" 1333:"Subsets of Rectifiable curves in Hilbert Space—The Analyst's TSP" 984:'s analyst's traveling salesman theorem may be stated as follows: 29: 1140:
is independent of dimension. (In particular, this involves using
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is the width of the smallest rectangle containing the portion of
1253:(1990). "Rectifiable sets and the Traveling Salesman Problem". 289:
is the set that is to be contained in a rectifiable curve,
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Let Δ denote the collection of dyadic squares, that is,
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can be contained in a curve with length no more than
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With some slight modifications to the definition of
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For a set 565:Jones' traveling salesman theorem in R 474:{\displaystyle 2\beta _{E}(Q)\ell (Q)} 1144:-numbers of balls instead of cubes). 992: > 0 such that whenever 7: 1160:) to get a condition for when a set 1028:Generalizations and Menger curvature 18:analyst's traveling salesman problem 260:{\displaystyle (x,L)<\delta \},} 1148:Menger curvature and metric spaces 928:is the square with same center as 834: 579: 557:gives a scale invariant notion of 14: 1033:Euclidean space and Hilbert space 1441:Theorems in discrete mathematics 1102:{\displaystyle \mathbb {R} ^{d}} 1338:Journal d'Analyse Mathématique 967: 961: 877: 871: 859: 849: 806: 800: 682: 669: 657: 638: 632: 619: 607: 588: 544: 538: 468: 462: 456: 450: 377: 365: 325: 319: 242: 230: 138: 132: 117: 111: 1: 550:{\displaystyle \beta _{E}(Q)} 216:{\displaystyle x\in E\cap Q,} 745:{\displaystyle \mathbb {Z} } 390:measures the distance from 1457: 26:combinatorial optimization 22:traveling salesman problem 1362:10.1007/s11854-008-0011-y 1023:(Γ) < CH(Γ). 973:{\displaystyle 3\ell (Q)} 1315:10.1112/jlms/s2-46.2.336 1255:Inventiones Mathematicae 1168:may be contained in the 996:is a set with such that 331:{\displaystyle \ell (Q)} 41:A rectifiable curve has 1194: 1103: 1070: 974: 942: 922: 884: 781: 746: 721: 551: 515: 495: 475: 424: 404: 384: 352: 338:is the side length of 332: 303: 283: 261: 217: 182: 162: 86: 1195: 1104: 1071: 975: 943: 923: 885: 782: 747: 722: 552: 516: 496: 476: 425: 405: 385: 383:{\displaystyle (x,L)} 353: 333: 304: 284: 262: 218: 183: 163: 87: 1232:totally disconnected 1228:Denjoy–Riesz theorem 1222:Denjoy–Riesz theorem 1176: 1084: 1045: 1004:) < ∞, 952: 932: 909: 794: 756: 734: 576: 525: 505: 485: 434: 414: 394: 362: 342: 313: 293: 273: 227: 192: 172: 98: 61: 20:is an analog of the 1267:1990InMat.102....1J 1172:-image of a subset 1275:10.1007/BF01233418 1190: 1099: 1066: 988:There is a number 970: 938: 921:{\displaystyle 3Q} 918: 880: 838: 777: 742: 717: 547: 511: 491: 471: 420: 400: 380: 348: 328: 299: 279: 257: 213: 188:so that for every 178: 158: 82: 30:rectifiable curves 1426:Harmonic analysis 1406:10.4064/fm185-2-3 948:with side length 941:{\displaystyle Q} 823: 815: 514:{\displaystyle Q} 494:{\displaystyle E} 423:{\displaystyle L} 403:{\displaystyle x} 351:{\displaystyle Q} 302:{\displaystyle Q} 282:{\displaystyle E} 181:{\displaystyle L} 142: 47:Hausdorff measure 1448: 1411: 1410: 1408: 1381: 1375: 1374: 1364: 1354: 1325: 1319: 1318: 1293: 1287: 1286: 1247: 1212:Menger curvature 1206:menger curvature 1199: 1197: 1196: 1191: 1189: 1164:of an arbitrary 1132:that lie in any 1108: 1106: 1105: 1100: 1098: 1097: 1092: 1075: 1073: 1072: 1067: 1065: 1064: 1059: 979: 977: 976: 971: 947: 945: 944: 939: 927: 925: 924: 919: 889: 887: 886: 881: 867: 866: 848: 847: 837: 816: 813: 786: 784: 783: 778: 776: 775: 770: 751: 749: 748: 743: 741: 726: 724: 723: 718: 710: 681: 680: 653: 652: 631: 630: 603: 602: 556: 554: 553: 548: 537: 536: 520: 518: 517: 512: 500: 498: 497: 492: 480: 478: 477: 472: 449: 448: 429: 427: 426: 421: 409: 407: 406: 401: 389: 387: 386: 381: 357: 355: 354: 349: 337: 335: 334: 329: 308: 306: 305: 300: 288: 286: 285: 280: 266: 264: 263: 258: 222: 220: 219: 214: 187: 185: 184: 179: 168:there is a line 167: 165: 164: 159: 157: 143: 141: 124: 110: 109: 91: 89: 88: 83: 81: 80: 75: 1456: 1455: 1451: 1450: 1449: 1447: 1446: 1445: 1416: 1415: 1414: 1383: 1382: 1378: 1327: 1326: 1322: 1295: 1294: 1290: 1249: 1248: 1244: 1240: 1224: 1204:-numbers using 1174: 1173: 1150: 1087: 1082: 1081: 1054: 1043: 1042: 1035: 1030: 950: 949: 930: 929: 907: 906: 858: 839: 792: 791: 765: 754: 753: 732: 731: 672: 644: 622: 594: 574: 573: 567: 528: 523: 522: 503: 502: 483: 482: 440: 432: 431: 430:. Intuitively, 412: 411: 392: 391: 360: 359: 340: 339: 311: 310: 309:is any square, 291: 290: 271: 270: 267: 225: 224: 190: 189: 170: 169: 128: 101: 96: 95: 70: 59: 58: 39: 12: 11: 5: 1454: 1452: 1444: 1443: 1438: 1433: 1428: 1418: 1417: 1413: 1412: 1399:(2): 143–169. 1385:Hahlomaa, Immo 1376: 1320: 1309:(2): 336–348. 1297:Okikiolu, Kate 1288: 1241: 1239: 1236: 1223: 1220: 1188: 1184: 1181: 1149: 1146: 1096: 1091: 1063: 1058: 1053: 1050: 1034: 1031: 1029: 1026: 1025: 1024: 1017: 969: 966: 963: 960: 957: 937: 917: 914: 891: 890: 879: 876: 873: 870: 865: 861: 857: 854: 851: 846: 842: 836: 833: 830: 826: 822: 819: 811: 808: 805: 802: 799: 774: 769: 764: 761: 740: 728: 727: 716: 713: 709: 705: 702: 699: 696: 693: 690: 687: 684: 679: 675: 671: 668: 665: 662: 659: 656: 651: 647: 643: 640: 637: 634: 629: 625: 621: 618: 615: 612: 609: 606: 601: 597: 593: 590: 587: 584: 581: 566: 563: 546: 543: 540: 535: 531: 510: 490: 470: 467: 464: 461: 458: 455: 452: 447: 443: 439: 419: 399: 379: 376: 373: 370: 367: 347: 327: 324: 321: 318: 298: 278: 256: 253: 250: 247: 244: 241: 238: 235: 232: 212: 209: 206: 203: 200: 197: 177: 155: 152: 149: 146: 140: 137: 134: 131: 127: 122: 119: 116: 113: 108: 104: 94: 79: 74: 69: 66: 38: 35: 13: 10: 9: 6: 4: 3: 2: 1453: 1442: 1439: 1437: 1434: 1432: 1431:Real analysis 1429: 1427: 1424: 1423: 1421: 1407: 1402: 1398: 1394: 1390: 1386: 1380: 1377: 1372: 1368: 1363: 1358: 1353: 1348: 1344: 1340: 1339: 1334: 1330: 1329:Schul, Raanan 1324: 1321: 1316: 1312: 1308: 1304: 1303: 1298: 1292: 1289: 1284: 1280: 1276: 1272: 1268: 1264: 1260: 1256: 1252: 1246: 1243: 1237: 1235: 1233: 1229: 1221: 1219: 1217: 1213: 1209: 1207: 1203: 1182: 1179: 1171: 1167: 1163: 1159: 1155: 1147: 1145: 1143: 1139: 1135: 1134:Hilbert Space 1131: 1127: 1123: 1118: 1116: 1112: 1094: 1079: 1061: 1051: 1048: 1040: 1039:Kate Okikiolu 1032: 1027: 1022: 1018: 1015: 1011: 1007: 1003: 999: 995: 991: 987: 986: 985: 983: 964: 958: 955: 935: 915: 912: 904: 900: 896: 874: 868: 863: 855: 852: 844: 840: 831: 828: 824: 820: 817: 809: 803: 797: 790: 789: 788: 772: 762: 759: 714: 703: 700: 697: 694: 691: 688: 685: 677: 673: 666: 663: 660: 654: 649: 645: 641: 635: 627: 623: 616: 613: 610: 604: 599: 595: 591: 582: 572: 571: 570: 562: 560: 541: 533: 529: 508: 488: 465: 459: 453: 445: 441: 437: 417: 397: 374: 371: 368: 345: 322: 316: 296: 276: 254: 248: 245: 239: 236: 233: 210: 207: 204: 201: 198: 195: 175: 153: 150: 135: 129: 125: 120: 114: 106: 102: 93: 77: 67: 64: 55: 52: 48: 44: 36: 34: 31: 27: 23: 19: 1396: 1392: 1379: 1352:math/0602675 1342: 1336: 1323: 1306: 1300: 1291: 1258: 1254: 1251:Jones, Peter 1245: 1225: 1215: 1210: 1201: 1166:metric space 1161: 1157: 1153: 1151: 1141: 1137: 1129: 1125: 1121: 1119: 1114: 1110: 1077: 1036: 1020: 1013: 1009: 1005: 1001: 997: 993: 989: 902: 894: 892: 729: 568: 558: 521:, and hence 410:to the line 268: 56: 50: 40: 17: 15: 1345:: 331–375. 982:Peter Jones 893:where diam 1420:Categories 1393:Fund. Math 1238:References 1218:-numbers. 358:, and dist 1283:123337823 1183:⊆ 1170:Lipschitz 1052:⊆ 959:ℓ 869:ℓ 841:β 835:Δ 832:∈ 825:∑ 798:β 787:, define 763:⊆ 704:∈ 636:× 580:Δ 530:β 460:ℓ 442:β 317:ℓ 249:δ 205:∩ 199:∈ 151:δ 130:ℓ 103:β 68:⊂ 37:β-numbers 1436:Geometry 1387:(2005). 1371:17223641 1331:(2007). 1261:: 1–15. 899:diameter 559:flatness 43:tangents 1263:Bibcode 980:. Then 897:is the 501:inside 1369:  1281:  730:where 269:where 1367:S2CID 1347:arXiv 1279:S2CID 1226:The 905:and 814:diam 246:< 223:dist 51:flat 16:The 1401:doi 1397:185 1357:doi 1343:103 1311:doi 1271:doi 1259:102 901:of 145:inf 92:: 24:in 1422:: 1395:. 1391:. 1365:. 1355:. 1341:. 1335:. 1307:46 1305:. 1277:. 1269:. 1257:. 1117:. 1076:, 1016:). 1010:Cβ 561:. 1409:. 1403:: 1373:. 1359:: 1349:: 1317:. 1313:: 1285:. 1273:: 1265:: 1216:β 1202:β 1187:R 1180:A 1162:E 1158:E 1156:( 1154:β 1142:β 1138:C 1130:E 1126:E 1124:( 1122:β 1115:d 1111:C 1095:d 1090:R 1078:d 1062:d 1057:R 1049:E 1021:β 1014:E 1012:( 1006:E 1002:E 1000:( 998:β 994:E 990:C 968:) 965:Q 962:( 956:3 936:Q 916:Q 913:3 903:E 895:E 878:) 875:Q 872:( 864:2 860:) 856:Q 853:3 850:( 845:E 829:Q 821:+ 818:E 810:= 807:) 804:E 801:( 773:2 768:R 760:E 739:Z 715:, 712:} 708:Z 701:k 698:, 695:j 692:, 689:i 686:: 683:] 678:k 674:2 670:) 667:1 664:+ 661:j 658:( 655:, 650:k 646:2 642:j 639:[ 633:] 628:k 624:2 620:) 617:1 614:+ 611:i 608:( 605:, 600:k 596:2 592:i 589:[ 586:{ 583:= 545:) 542:Q 539:( 534:E 509:Q 489:E 469:) 466:Q 463:( 457:) 454:Q 451:( 446:E 438:2 418:L 398:x 378:) 375:L 372:, 369:x 366:( 346:Q 326:) 323:Q 320:( 297:Q 277:E 255:, 252:} 243:) 240:L 237:, 234:x 231:( 211:, 208:Q 202:E 196:x 176:L 154:: 148:{ 139:) 136:Q 133:( 126:1 121:= 118:) 115:Q 112:( 107:E 78:2 73:R 65:E

Index

traveling salesman problem
combinatorial optimization
rectifiable curves
tangents
Hausdorff measure
diameter
Peter Jones
Kate Okikiolu
Hilbert Space
metric space
Lipschitz
menger curvature
Menger curvature
Denjoy–Riesz theorem
totally disconnected
Jones, Peter
Bibcode
1990InMat.102....1J
doi
10.1007/BF01233418
S2CID
123337823
Okikiolu, Kate
Journal of the London Mathematical Society
doi
10.1112/jlms/s2-46.2.336
Schul, Raanan
"Subsets of Rectifiable curves in Hilbert Space—The Analyst's TSP"
Journal d'Analyse Mathématique
arXiv

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