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Topological quantum number

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it with a point at infinity, one also gets a 3-sphere. Solutions to Skyrme's equations in real three-dimensional space map a point in "real" (physical; Euclidean) space to a point on the 3-manifold SU(2). Topologically distinct solutions "wrap" the one sphere around the other, such that one solution,
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no matter how it is deformed, cannot be "unwrapped" without creating a discontinuity in the solution. In physics, such discontinuities are associated with infinite energy, and are thus not allowed.
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modeling a physical system, as the solitons themselves owe their stability to topological considerations. The specific "topological considerations" are usually due to the appearance of the
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are specified, has a non-trivial homotopy group that is preserved by the differential equations. The topological quantum number of a solution is sometimes called the
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through its bijective association, so the isomorphism is in the category of topological groups. By taking real three-dimensional space, and
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Vanhala, Tuomas I.; Siro, Topi; Liang, Long; Troyer, Matthias; Harju, Ari; TörmÀ, PÀivi (2016-06-02).
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In the above example, the topological statement is that the 3rd homotopy group of the three sphere is
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theoretical model demonstrated that materials can possess topological quantum numbers like the
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Physical quantities that take discrete values because of topological quantum physical effects
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shows that a fractional number of fermions repelled over the ultraviolet cutoff. So the
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Hao, Ningning; Zhang, Ping; Wang, Zhigang; Zhang, Wei; Wang, Yupeng (2008-08-26).
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in the description of the problem, quite often because the boundary, on which the
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The concept of topological quantum numbers being created or destroyed during
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is a topological quantum number. The origin comes from the fact that the
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monopole model demonstrated how topological structures, such as
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considerations. Most commonly, topological quantum numbers are
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Scientific Background on the Nobel Prize in Physics 2016.
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and so the baryon number can only take on integer values.
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Topological Quantum Numbers in Nonrelativistic Physics
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gets multiplied by a fractional number depending on
51:. Unsourced material may be challenged and removed. 520: 490: 457: 395:Additional examples can be found in the domain of 369: 303: 276: 383:A generalization of these ideas is found in the 171:of the solution, or, more precisely, it is the 627:"Introduction to Topological Quantum Numbers" 8: 458:{\displaystyle \pi _{1}(S^{1})=\mathbb {Z} } 370:{\displaystyle \pi _{3}(S^{3})=\mathbb {Z} } 660:: CS1 maint: numeric names: authors list ( 767: 726: 514: 513: 511: 484: 483: 481: 451: 450: 438: 425: 419: 363: 362: 350: 337: 331: 295: 289: 268: 262: 111:Learn how and when to remove this message 617: 653: 7: 49:adding citations to reliable sources 14: 601:Topological quantum field theory 311:inherits the group structure of 25: 544:, certain types of crystalline 151:-type solutions of some set of 36:needs additional citations for 778:10.1103/PhysRevLett.116.225305 675:Năstase, HoraÆ«iu, ed. (2019), 591:Topological entropy in physics 444: 431: 356: 343: 188:Kosterlitz-Thouless Transition 173:degree of a continuous mapping 1: 254:, which is isomorphic to the 238:, an example is given by the 566:Inverse scattering transform 521:{\displaystyle \mathbb {Z} } 491:{\displaystyle \mathbb {Z} } 60:"Topological quantum number" 845: 737:10.1103/PhysRevB.78.075438 405:Korteweg–de Vries equation 129:topological quantum number 606:Topological string theory 790:Thouless, D. J. (1998). 385:Wess–Zumino–Witten model 184:condensed matter physics 159:or a higher-dimensional 824:Exactly solvable models 756:Physical Review Letters 397:exactly solvable models 391:Exactly solvable models 681:Classical Field Theory 522: 492: 468:and so is literally a 459: 371: 305: 278: 224:topological insulators 153:differential equations 141:topological invariants 523: 493: 460: 372: 306: 304:{\displaystyle S^{3}} 279: 277:{\displaystyle S^{3}} 829:Quantum field theory 794:. World Scientific. 510: 480: 418: 401:sine-Gordon equation 330: 288: 261: 200:quantum field theory 45:improve this article 542:solid state physics 536:Solid state physics 192:topological defects 165:boundary conditions 145:topological defects 586:Topological defect 554:Germanium whiskers 550:screw dislocations 518: 498:is the number of 488: 455: 367: 301: 274: 208:magnetic monopoles 133:topological charge 715:Physical Review B 690:978-1-108-47701-7 596:Topological order 576:Quantum invariant 409:Ishimori equation 190:demonstrated how 186:in the 1970s.The 180:phase transitions 157:fundamental group 121: 120: 113: 95: 836: 805: 782: 781: 771: 747: 741: 740: 730: 706: 700: 699: 698: 697: 672: 666: 665: 659: 651: 649: 640: 634: 633: 631: 622: 581:Quantum topology 527: 525: 524: 519: 517: 497: 495: 494: 489: 487: 464: 462: 461: 456: 454: 443: 442: 430: 429: 376: 374: 373: 368: 366: 355: 354: 342: 341: 310: 308: 307: 302: 300: 299: 283: 281: 280: 275: 273: 272: 242:, for which the 236:particle physics 230:Particle physics 204:t Hooft-Polyakov 143:associated with 116: 109: 105: 102: 96: 94: 53: 29: 21: 844: 843: 839: 838: 837: 835: 834: 833: 809: 808: 802: 789: 786: 785: 749: 748: 744: 708: 707: 703: 695: 693: 691: 674: 673: 669: 652: 647: 642: 641: 637: 629: 625:Thouless, D.J. 624: 623: 619: 614: 562: 538: 508: 507: 504:renormalization 478: 477: 434: 421: 416: 415: 393: 346: 333: 328: 327: 291: 286: 285: 264: 259: 258: 250:is modelled by 232: 117: 106: 100: 97: 54: 52: 42: 30: 17: 12: 11: 5: 842: 840: 832: 831: 826: 821: 811: 810: 807: 806: 800: 784: 783: 762:(22): 225305. 742: 701: 689: 667: 635: 616: 615: 613: 610: 609: 608: 603: 598: 593: 588: 583: 578: 573: 571:Central charge 568: 561: 558: 537: 534: 516: 486: 474:Thirring model 470:winding number 466: 465: 453: 449: 446: 441: 437: 433: 428: 424: 399:, such as the 392: 389: 378: 377: 365: 361: 358: 353: 349: 345: 340: 336: 298: 294: 271: 267: 231: 228: 169:winding number 161:homotopy group 119: 118: 33: 31: 24: 15: 13: 10: 9: 6: 4: 3: 2: 841: 830: 827: 825: 822: 820: 817: 816: 814: 803: 801:981-02-2900-3 797: 793: 788: 787: 779: 775: 770: 765: 761: 757: 753: 746: 743: 738: 734: 729: 724: 721:(7): 075438. 720: 716: 712: 705: 702: 692: 686: 682: 678: 671: 668: 663: 657: 646: 639: 636: 628: 621: 618: 611: 607: 604: 602: 599: 597: 594: 592: 589: 587: 584: 582: 579: 577: 574: 572: 569: 567: 564: 563: 559: 557: 555: 551: 547: 543: 535: 533: 531: 505: 501: 475: 471: 447: 439: 435: 426: 422: 414: 413: 412: 410: 406: 402: 398: 390: 388: 386: 381: 359: 351: 347: 338: 334: 326: 325: 324: 321: 318: 314: 296: 292: 269: 265: 257: 253: 249: 245: 244:baryon number 241: 237: 229: 227: 225: 221: 217: 213: 209: 205: 201: 197: 193: 189: 185: 181: 176: 174: 170: 166: 162: 158: 154: 150: 146: 142: 138: 134: 131:(also called 130: 126: 115: 112: 104: 101:February 2010 93: 90: 86: 83: 79: 76: 72: 69: 65: 62: â€“  61: 57: 56:Find sources: 50: 46: 40: 39: 34:This article 32: 28: 23: 22: 19: 791: 759: 755: 745: 718: 714: 704: 694:, retrieved 680: 670: 638: 620: 546:dislocations 539: 467: 394: 382: 379: 322: 233: 220:Hall effects 216:Chern number 177: 132: 128: 122: 107: 98: 88: 81: 74: 67: 55: 43:Please help 38:verification 35: 18: 182:emerged in 137:topological 813:Categories 769:1512.08804 696:2024-08-24 612:References 548:, such as 532:constant. 407:, and the 71:newspapers 728:0901.0050 423:π 335:π 212:Haldane's 819:Solitons 656:cite web 560:See also 500:fermions 256:3-sphere 240:Skyrmion 196:vortices 403:, the 317:closing 248:isospin 194:, like 149:soliton 125:physics 85:scholar 798:  687:  530:Planck 87:  80:  73:  66:  58:  764:arXiv 723:arXiv 648:(PDF) 630:(PDF) 313:SU(2) 252:SU(2) 202:the ' 92:JSTOR 78:books 796:ISBN 685:ISBN 662:link 284:and 222:and 127:, a 64:news 774:doi 760:116 733:doi 540:In 234:In 147:or 123:In 47:by 815:: 772:. 758:. 754:. 731:. 719:78 717:. 713:. 679:, 658:}} 654:{{ 556:. 387:. 226:. 175:. 804:. 780:. 776:: 766:: 739:. 735:: 725:: 664:) 650:. 632:. 515:Z 485:Z 452:Z 448:= 445:) 440:1 436:S 432:( 427:1 364:Z 360:= 357:) 352:3 348:S 344:( 339:3 297:3 293:S 270:3 266:S 114:) 108:( 103:) 99:( 89:· 82:· 75:· 68:· 41:.

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"Topological quantum number"
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physics
topological
topological invariants
topological defects
soliton
differential equations
fundamental group
homotopy group
boundary conditions
winding number
degree of a continuous mapping
phase transitions
condensed matter physics
Kosterlitz-Thouless Transition
topological defects
vortices
quantum field theory
t Hooft-Polyakov
magnetic monopoles

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