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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
62:. Unsourced material may be challenged and removed. 531: 501: 468: 406:Additional examples can be found in the domain of 380: 314: 287: 394:A generalization of these ideas is found in the 182:of the solution, or, more precisely, it is the 638:"Introduction to Topological Quantum Numbers" 8: 469:{\displaystyle \pi _{1}(S^{1})=\mathbb {Z} } 381:{\displaystyle \pi _{3}(S^{3})=\mathbb {Z} } 671:: CS1 maint: numeric names: authors list ( 778: 737: 525: 524: 522: 495: 494: 492: 462: 461: 449: 436: 430: 374: 373: 361: 348: 342: 306: 300: 279: 273: 122:Learn how and when to remove this message 628: 664: 7: 60:adding citations to reliable sources 25: 612:Topological quantum field theory 322:inherits the group structure of 36: 555:, certain types of crystalline 162:-type solutions of some set of 47:needs additional citations for 789:10.1103/PhysRevLett.116.225305 686:Năstase, HoraÆ«iu, ed. (2019), 602:Topological entropy in physics 455: 442: 367: 354: 199:Kosterlitz-Thouless Transition 184:degree of a continuous mapping 1: 265:, which is isomorphic to the 249:, an example is given by the 577:Inverse scattering transform 532:{\displaystyle \mathbb {Z} } 502:{\displaystyle \mathbb {Z} } 71:"Topological quantum number" 856: 748:10.1103/PhysRevB.78.075438 416:Korteweg–de Vries equation 140:topological quantum number 18:Topological winding number 617:Topological string theory 801:Thouless, D. J. (1998). 396:Wess–Zumino–Witten model 195:condensed matter physics 170:or a higher-dimensional 835:Exactly solvable models 767:Physical Review Letters 408:exactly solvable models 402:Exactly solvable models 692:Classical Field Theory 533: 503: 479:and so is literally a 470: 382: 316: 289: 235:topological insulators 164:differential equations 152:topological invariants 534: 504: 471: 383: 317: 315:{\displaystyle S^{3}} 290: 288:{\displaystyle S^{3}} 840:Quantum field theory 805:. World Scientific. 521: 491: 429: 412:sine-Gordon equation 341: 299: 272: 211:quantum field theory 56:improve this article 553:solid state physics 547:Solid state physics 203:topological defects 176:boundary conditions 156:topological defects 597:Topological defect 565:Germanium whiskers 561:screw dislocations 529: 509:is the number of 499: 466: 378: 312: 285: 219:magnetic monopoles 144:topological charge 726:Physical Review B 701:978-1-108-47701-7 607:Topological order 587:Quantum invariant 420:Ishimori equation 201:demonstrated how 197:in the 1970s.The 191:phase transitions 168:fundamental group 132: 131: 124: 106: 16:(Redirected from 847: 816: 793: 792: 782: 758: 752: 751: 741: 717: 711: 710: 709: 708: 683: 677: 676: 670: 662: 660: 651: 645: 644: 642: 633: 592:Quantum topology 538: 536: 535: 530: 528: 508: 506: 505: 500: 498: 475: 473: 472: 467: 465: 454: 453: 441: 440: 387: 385: 384: 379: 377: 366: 365: 353: 352: 321: 319: 318: 313: 311: 310: 294: 292: 291: 286: 284: 283: 253:, for which the 247:particle physics 241:Particle physics 215:t Hooft-Polyakov 154:associated with 127: 120: 116: 113: 107: 105: 64: 40: 32: 21: 855: 854: 850: 849: 848: 846: 845: 844: 820: 819: 813: 800: 797: 796: 760: 759: 755: 719: 718: 714: 706: 704: 702: 685: 684: 680: 663: 658: 653: 652: 648: 640: 636:Thouless, D.J. 635: 634: 630: 625: 573: 549: 519: 518: 515:renormalization 489: 488: 445: 432: 427: 426: 404: 357: 344: 339: 338: 302: 297: 296: 275: 270: 269: 261:is modelled by 243: 128: 117: 111: 108: 65: 63: 53: 41: 28: 23: 22: 15: 12: 11: 5: 853: 851: 843: 842: 837: 832: 822: 821: 818: 817: 811: 795: 794: 773:(22): 225305. 753: 712: 700: 678: 646: 627: 626: 624: 621: 620: 619: 614: 609: 604: 599: 594: 589: 584: 582:Central charge 579: 572: 569: 548: 545: 527: 497: 485:Thirring model 481:winding number 477: 476: 464: 460: 457: 452: 448: 444: 439: 435: 410:, such as the 403: 400: 389: 388: 376: 372: 369: 364: 360: 356: 351: 347: 309: 305: 282: 278: 242: 239: 180:winding number 172:homotopy group 130: 129: 44: 42: 35: 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 852: 841: 838: 836: 833: 831: 828: 827: 825: 814: 812:981-02-2900-3 808: 804: 799: 798: 790: 786: 781: 776: 772: 768: 764: 757: 754: 749: 745: 740: 735: 732:(7): 075438. 731: 727: 723: 716: 713: 703: 697: 693: 689: 682: 679: 674: 668: 657: 650: 647: 639: 632: 629: 622: 618: 615: 613: 610: 608: 605: 603: 600: 598: 595: 593: 590: 588: 585: 583: 580: 578: 575: 574: 570: 568: 566: 562: 558: 554: 546: 544: 542: 516: 512: 486: 482: 458: 450: 446: 437: 433: 425: 424: 423: 421: 417: 413: 409: 401: 399: 397: 392: 370: 362: 358: 349: 345: 337: 336: 335: 332: 329: 325: 307: 303: 280: 276: 268: 264: 260: 256: 255:baryon number 252: 248: 240: 238: 236: 232: 228: 224: 220: 216: 212: 208: 204: 200: 196: 192: 187: 185: 181: 177: 173: 169: 165: 161: 157: 153: 149: 145: 142:(also called 141: 137: 126: 123: 115: 112:February 2010 104: 101: 97: 94: 90: 87: 83: 80: 76: 73: â€“  72: 68: 67:Find sources: 61: 57: 51: 50: 45:This article 43: 39: 34: 33: 30: 19: 802: 770: 766: 756: 729: 725: 715: 705:, retrieved 691: 681: 649: 631: 557:dislocations 550: 478: 405: 393: 390: 333: 244: 231:Hall effects 227:Chern number 188: 143: 139: 133: 118: 109: 99: 92: 85: 78: 66: 54:Please help 49:verification 46: 29: 193:emerged in 148:topological 824:Categories 780:1512.08804 707:2024-08-24 623:References 559:, such as 543:constant. 418:, and the 82:newspapers 739:0901.0050 434:π 346:π 223:Haldane's 830:Solitons 667:cite web 571:See also 511:fermions 267:3-sphere 251:Skyrmion 207:vortices 414:, the 328:closing 259:isospin 205:, like 160:soliton 136:physics 96:scholar 809:  698:  541:Planck 98:  91:  84:  77:  69:  775:arXiv 734:arXiv 659:(PDF) 641:(PDF) 324:SU(2) 263:SU(2) 213:the ' 103:JSTOR 89:books 807:ISBN 696:ISBN 673:link 295:and 233:and 138:, a 75:news 785:doi 771:116 744:doi 551:In 245:In 158:or 134:In 58:by 826:: 783:. 769:. 765:. 742:. 730:78 728:. 724:. 690:, 669:}} 665:{{ 567:. 398:. 237:. 186:. 815:. 791:. 787:: 777:: 750:. 746:: 736:: 675:) 661:. 643:. 526:Z 496:Z 463:Z 459:= 456:) 451:1 447:S 443:( 438:1 375:Z 371:= 368:) 363:3 359:S 355:( 350:3 308:3 304:S 281:3 277:S 125:) 119:( 114:) 110:( 100:· 93:· 86:· 79:· 52:. 20:)

Index

Topological winding number

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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

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