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Talk:Link (knot theory)

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sufficiently small real 3-sphere centred at the singularity. If the singular point is isolated, then the real link is a one-dimensional manifold in a 3-dimensional space. Thus the link is of interest to knot theorists. And as you increase the dimensions of things you get these more general links. Some mention of braid monodromy would be nice too. I don't want to touch the article: it's very beautiful and my Knowledge editing skills are next to nothing. If you need advice on the singularity theory then I can help you with that :o)
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collection of manifolds. This agrees with the historical usage of the word link. Is that what you're getting at? The knot theory articles on wikipedia all have that slant. This "link" definition is still a stub and biased towards plain-jane traditional 3-dimensional knot/link theory. Not much effort has been put into it yet. You're welcome to improve it.
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p.s. The milnor fibre is the wedged product of μ spheres where μ is the Milnor number of the singular function germ, i.e. the local multiplicity, i.e. the dimension of the local algebra. To compute this number you take the ring of function germs and quotient out by the Jacobian ideal, i.e. the ideal
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Your example fits the basic definition of this article -- in fact the usage of "link" in singularity theory is derived from the manifold-theoretic usage of the word. I suppose "link" in the singularity-theoretic sense does not have to be a knotted collection of spheres but in general just a knotted
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It's getting better. I guess I'm just biased: I would love to see some mention of links in applications, e.g. singularity theory. For example a complex curve in the plane is a real two-dimensional body in four-dimensional space. The real link of a singularity on the curve is the intersection of a
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These are called the Milnor fibres. Then for small ε we intersect the milnor fibre with a sufficiently small hypersphere. The resulting intersection is called the link of the singularity. The topology of this link is of great importance. Moreover, varying ε along a closed path which does not pass
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IMO most of what you're talking about would be more appropriately placed in a topic like "fibred link". Links in general are not fibred so there's no monodromy to speak of -- there is a vague analogue in that you could talk about the action of the fundamental group of the link on the commutator
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generated by all first order partial derivatives. Since the function is assumed to have an isolated singularity it follows that this is a finite dimensional vector space: the local algebra. For an example, consider
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You're quite right. Although I am feeling quite puzzled. I don't remember seeing the "more generally" section the last time I looked. There must have been a problem with my web browser, or my eyes. Sorry
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subgroup or equivalently on the homotopy-fibre of the "abelianization map" from the link complement to the appropriate product of circles. But that's kind of a different topic.
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First I'd like to say that it is an attractive article with some nice pictures. However, it should be mentioned that there are other uses of the word
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While not as scientifically "sexy" a subject as singularities, has there been any attempt to apply knot theory to chainmaille?
345: 168: 99: 30: 135: 104: 20: 74: 865:{\displaystyle {\mathcal {A}}_{f}={\frac {{\mathcal {O}}(x,y)}{\langle x^{2},y^{2}\rangle }}=\langle 1,x,y,xy\rangle \ .} 674: 202: 513:
through the origin gives a mapping from the homology of the link to itself, and induces what is called the monodromy.
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on Knowledge. If you would like to participate, please visit the project page, where you can join
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Then we get a locally trivial fibration over the complex plane minus the origin. We consider
502:{\displaystyle F_{\epsilon }:=\{z\in \mathbb {C} ^{n}:f(z)=\epsilon ,\ \epsilon \neq 0\}\ .} 931: 571: 534: 970: 271: 248: 961: 935: 927: 919: 594: 575: 567: 557: 538: 530: 522: 910:, and so the link is homeomorphic to the wedged product of four spheres. 566:
I've touched it up a little. What do you think? Still needs some work.
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Then the Jacobian ideal is just 284:Knowledge:WikiProject Mathematics 287:Template:WikiProject Mathematics 251: 241: 220: 189: 45:Click here to start a new topic. 977:Stub-Class mathematics articles 304:This article has been rated as 891: 885: 787: 775: 628: 616: 468: 462: 396: 382: 379: 376: 355: 1: 278:and see a list of open tasks. 42:Put new text under old text. 962:17:23, 3 January 2012 (UTC) 936:01:09, 14 August 2008 (UTC) 920:22:31, 13 August 2008 (UTC) 595:22:14, 13 August 2008 (UTC) 576:21:59, 13 August 2008 (UTC) 558:21:51, 13 August 2008 (UTC) 539:21:37, 13 August 2008 (UTC) 523:20:16, 13 August 2008 (UTC) 50:New to Knowledge? Welcome! 998: 903:{\displaystyle \mu (f)=4} 333:link (and disambiguation) 303: 236: 215: 80:Be welcoming to newcomers 310:project's priority scale 267:WikiProject Mathematics 904: 866: 729: 661: 503: 403: 197:This article is rated 75:avoid personal attacks 905: 875:It follows then that 867: 730: 662: 504: 404: 100:Neutral point of view 879: 745: 675: 610: 419: 346: 290:mathematics articles 105:No original research 900: 862: 725: 657: 499: 399: 259:Mathematics portal 203:content assessment 86:dispute resolution 47: 25:Link (knot theory) 952:comment added by 858: 822: 721: 495: 481: 324: 323: 320: 319: 316: 315: 183: 182: 66:Assume good faith 43: 989: 964: 909: 907: 906: 901: 871: 869: 868: 863: 857: 823: 821: 817: 816: 804: 803: 790: 774: 773: 766: 761: 760: 755: 754: 734: 732: 731: 726: 720: 716: 715: 703: 702: 687: 686: 666: 664: 663: 658: 656: 655: 643: 642: 508: 506: 505: 500: 494: 480: 455: 454: 449: 431: 430: 408: 406: 405: 400: 389: 369: 368: 363: 292: 291: 288: 285: 282: 261: 256: 255: 245: 238: 237: 232: 224: 217: 200: 194: 193: 185: 179: 178: 164: 95:Article policies 16: 997: 996: 992: 991: 990: 988: 987: 986: 967: 966: 947: 944: 877: 876: 808: 795: 791: 767: 748: 743: 742: 707: 694: 678: 673: 672: 647: 634: 608: 607: 444: 422: 417: 416: 358: 344: 343: 329: 289: 286: 283: 280: 279: 257: 250: 230: 201:on Knowledge's 198: 121: 116: 115: 114: 91: 61: 12: 11: 5: 995: 993: 985: 984: 979: 969: 968: 943: 940: 939: 938: 899: 896: 893: 890: 887: 884: 873: 872: 861: 856: 853: 850: 847: 844: 841: 838: 835: 832: 829: 826: 820: 815: 811: 807: 802: 798: 794: 789: 786: 783: 780: 777: 772: 764: 759: 753: 736: 735: 724: 719: 714: 710: 706: 701: 697: 693: 690: 685: 681: 670: 669: 668: 654: 650: 646: 641: 637: 633: 630: 627: 624: 621: 618: 615: 600: 599: 598: 597: 579: 578: 563: 562: 561: 560: 542: 541: 510: 509: 498: 493: 490: 487: 484: 479: 476: 473: 470: 467: 464: 461: 458: 453: 448: 443: 440: 437: 434: 429: 425: 410: 409: 398: 395: 392: 388: 384: 381: 378: 375: 372: 367: 362: 357: 354: 351: 328: 325: 322: 321: 318: 317: 314: 313: 302: 296: 295: 293: 276:the discussion 263: 262: 246: 234: 233: 225: 213: 212: 206: 195: 181: 180: 118: 117: 113: 112: 107: 102: 93: 92: 90: 89: 82: 77: 68: 62: 60: 59: 48: 39: 38: 35: 34: 28: 13: 10: 9: 6: 4: 3: 2: 994: 983: 980: 978: 975: 974: 972: 965: 963: 959: 955: 954:67.142.178.20 951: 941: 937: 933: 929: 924: 923: 922: 921: 917: 913: 912:Dharma6662000 897: 894: 888: 882: 859: 851: 848: 845: 842: 839: 836: 833: 830: 824: 813: 809: 805: 800: 796: 784: 781: 778: 762: 757: 741: 740: 739: 722: 712: 708: 704: 699: 695: 688: 683: 679: 671: 652: 648: 644: 639: 635: 631: 625: 622: 619: 613: 604: 603: 602: 601: 596: 592: 588: 587:Dharma6662000 583: 582: 581: 580: 577: 573: 569: 565: 564: 559: 555: 551: 550:Dharma6662000 546: 545: 544: 543: 540: 536: 532: 527: 526: 525: 524: 520: 516: 515:Dharma6662000 496: 488: 485: 482: 477: 474: 471: 465: 459: 456: 451: 441: 438: 432: 427: 423: 415: 414: 413: 393: 390: 373: 370: 365: 352: 349: 342: 341: 340: 338: 334: 326: 311: 307: 301: 298: 297: 294: 277: 273: 269: 268: 260: 254: 249: 247: 244: 240: 239: 235: 229: 226: 223: 219: 214: 210: 204: 196: 192: 187: 186: 177: 173: 170: 167: 163: 159: 155: 152: 149: 146: 143: 140: 137: 134: 131: 127: 124: 123:Find sources: 120: 119: 111: 110:Verifiability 108: 106: 103: 101: 98: 97: 96: 87: 83: 81: 78: 76: 72: 69: 67: 64: 63: 57: 53: 52:Learn to edit 49: 46: 41: 40: 37: 36: 32: 26: 22: 18: 17: 948:— Preceding 945: 874: 737: 511: 411: 336: 330: 327:Too Specific 306:Low-priority 305: 265: 231:Low‑priority 209:WikiProjects 171: 165: 157: 150: 144: 138: 132: 122: 94: 19:This is the 942:Chainmaille 281:Mathematics 272:mathematics 228:Mathematics 148:free images 31:not a forum 971:Categories 199:Stub-class 88:if needed 71:Be polite 21:talk page 950:unsigned 56:get help 29:This is 27:article. 308:on the 154:WP refs 142:scholar 205:scale. 126:Google 169:JSTOR 130:books 84:Seek 958:talk 932:talk 928:Rybu 916:talk 591:talk 572:talk 568:Rybu 554:talk 535:talk 531:Rybu 519:talk 162:FENS 136:news 73:and 300:Low 176:TWL 973:: 960:) 934:) 918:) 883:μ 855:⟩ 828:⟨ 819:⟩ 793:⟨ 718:⟩ 692:⟨ 593:) 574:) 556:) 537:) 521:) 486:≠ 483:ϵ 475:ϵ 442:∈ 433::= 428:ϵ 380:→ 156:) 54:; 956:( 930:( 914:( 898:4 895:= 892:) 889:f 886:( 860:. 852:y 849:x 846:, 843:y 840:, 837:x 834:, 831:1 825:= 814:2 810:y 806:, 801:2 797:x 788:) 785:y 782:, 779:x 776:( 771:O 763:= 758:f 752:A 723:. 713:2 709:y 705:, 700:2 696:x 689:= 684:f 680:J 653:3 649:y 645:+ 640:3 636:x 632:= 629:) 626:y 623:, 620:x 617:( 614:f 589:( 570:( 552:( 533:( 517:( 497:. 492:} 489:0 478:, 472:= 469:) 466:z 463:( 460:f 457:: 452:n 447:C 439:z 436:{ 424:F 397:) 394:0 391:, 387:C 383:( 377:) 374:0 371:, 366:n 361:C 356:( 353:: 350:f 337:f 312:. 211:: 172:· 166:· 158:· 151:· 145:· 139:· 133:· 128:( 58:.

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