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Gauss map

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The Gauss map provides a mapping from every point on a curve or a surface to a corresponding point on a unit sphere. In this example, the curvature of a 2D-surface is mapped onto a 1D unit circle.
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A surface with a parabolic line and its Gauss map. A ridge passes through the parabolic line giving rise to a cusp on the Gauss map.
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The Gauss map reflects many properties of the surface: when the surface has zero Gaussian curvature, (that is along a
477: 253: 51: 45: 37: 1090: 474:, this says that an oriented 2-plane is characterized by an oriented 1-line, equivalently a unit normal vector (as 264: 17: 272: 257: 813: 803:{\displaystyle \iint _{R}\pm |N_{u}\times N_{v}|\ du\,dv=\iint _{R}K|X_{u}\times X_{v}|\ du\,dv=\iint _{S}K\ dA} 62: 208: 114: 1045: 587: 343: 102: 1034: 196: 181: 857: 547: 1070: 845: 841: 636: 222: 204: 110: 1156: 1065: 1060: 983: 958: 1080: 875: 632: 577: 1075: 937: 925: 853: 849: 471: 199:. The Gauss map can always be defined locally (i.e. on a small piece of the surface). The 130: 1095: 1085: 1055: 837: 566: 226: 212: 828: 1135: 338: 304: 929: 918: 327: 242: 153: 118: 977: 538:
Finally, the notion of Gauss map can be generalized to an oriented submanifold
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Thomas Banchoff; Terence Gaffney; Clint McCrory; Daniel Dreibelbis (1982).
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Gauss first wrote a draft on the topic in 1825 and published in 1827.
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The Gauss map can be defined (globally) if and only if the surface is
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This article is about differential geometry. For other uses, see
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the Gauss map can also be defined, and its target space is the
236: 22: 910:, English translation. Hewlett, New York: Raven Press (1965). 463:{\displaystyle {\tilde {G}}_{k,n}\cong {\tilde {G}}_{n-k,n}} 917:, (1982) Research Notes in Mathematics 55, Pitman, London. 639:. This is the original interpretation given by Gauss. 535:), hence this is consistent with the definition above. 874:
at the closure of the set of inflection points of the
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to the surface at that point. Namely, given a surface
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The area of the image of the Gauss map is called the
590: 480: 400: 346: 802: 611: 527: 462: 374: 901:Disquisitiones generales circa superficies curvas 311:as a map from a hypersurface to the unit sphere 50:but its sources remain unclear because it lacks 528:{\displaystyle {\tilde {G}}_{1,n}\cong S^{n-1}} 1019: 557:. In that case, the Gauss map then goes from 8: 271:. Unsourced material may be challenged and 1026: 1012: 1004: 816:links total curvature of a surface to its 908:General investigations of curved surfaces 848:and these cusps were studied in depth by 782: 768: 754: 748: 735: 726: 717: 703: 689: 683: 670: 661: 652: 646: 603: 598: 589: 513: 494: 483: 482: 479: 442: 431: 430: 414: 403: 402: 399: 360: 349: 348: 345: 291:Learn how and when to remove this message 203:determinant of the Gauss map is equal to 117:that maps each point in the surface to a 81:Learn how and when to remove this message 92: 913:Banchoff, T., Gaffney T., McCrory C., 572:. The target space for the Gauss map 7: 269:adding citations to reliable sources 864:The surface has a bi-tangent plane 612:{\displaystyle M=\mathbf {R} ^{n}} 394:subspace; these are equivalent as 375:{\displaystyle {\tilde {G}}_{k,n}} 14: 1147:Differential geometry of surfaces 303:The Gauss map can be defined for 172:) is a unit vector orthogonal to 1114: 1113: 599: 241: 221:There is also a Gauss map for a 27: 382:, i.e. the set of all oriented 211:of the Gauss map is called the 180:. The Gauss map is named after 930:Dan Dreibelbis' online version 755: 727: 690: 662: 488: 470:via orthogonal complement. In 436: 408: 354: 1: 882:There are two types of cusp: 840:) the Gauss map will have a 580:built on the tangent bundle 1178: 18:Gauss map (disambiguation) 15: 1109: 1101:Gauss's law for magnetism 1041: 631:and is equivalent to the 136:, the Gauss map is a map 871:crosses a parabolic line 844:. This fold may contain 36:This article includes a 1091:Gauss's law for gravity 979:Cusps of Gauss Mappings 932:(accessed 2023-07-01), 915:Cusps of Gauss Mappings 546:in an oriented ambient 322:For a general oriented 65:more precise citations. 833: 824:Cusps of the Gauss map 804: 613: 561:to the set of tangent 529: 464: 376: 156:) such that for each 98: 1142:Differential geometry 1046:Gauss composition law 831: 805: 614: 530: 465: 377: 164:, the function value 103:differential geometry 96: 1162:Carl Friedrich Gauss 1035:Carl Friedrich Gauss 928:<--broken link; 814:Gauss–Bonnet theorem 645: 588: 584:. In the case where 478: 398: 344: 265:improve this section 197:Euler characteristic 191:, in which case its 1152:Riemannian geometry 942:Koenderink, J. J., 548:Riemannian manifold 1071:Gaussian curvature 959:Weisstein, Eric W. 946:, MIT Press (1990) 936:2008-08-02 at the 924:2008-08-02 at the 834: 800: 637:Gaussian curvature 609: 525: 460: 372: 205:Gaussian curvature 99: 38:list of references 1129: 1128: 1066:Gaussian brackets 876:asymptotic curves 793: 761: 696: 491: 472:Euclidean 3-space 439: 411: 357: 301: 300: 293: 225:, which computes 91: 90: 83: 1169: 1117: 1116: 1081:Gaussian surface 1028: 1021: 1014: 1005: 1000: 998: 996: 972: 971: 888:hyperbolic cusps 842:fold catastrophe 809: 807: 806: 801: 791: 787: 786: 759: 758: 753: 752: 740: 739: 730: 722: 721: 694: 693: 688: 687: 675: 674: 665: 657: 656: 633:surface integral 618: 616: 615: 610: 608: 607: 602: 578:Grassmann bundle 534: 532: 531: 526: 524: 523: 505: 504: 493: 492: 484: 469: 467: 466: 461: 459: 458: 441: 440: 432: 425: 424: 413: 412: 404: 381: 379: 378: 373: 371: 370: 359: 358: 350: 296: 289: 285: 282: 276: 245: 237: 86: 79: 75: 72: 66: 61:this article by 52:inline citations 31: 30: 23: 1177: 1176: 1172: 1171: 1170: 1168: 1167: 1166: 1132: 1131: 1130: 1125: 1105: 1076:Gaussian period 1037: 1032: 994: 992: 990: 975: 957: 956: 953: 938:Wayback Machine 926:Wayback Machine 896: 878:of the surface. 854:Terence Gaffney 850:Thomas Banchoff 826: 778: 744: 731: 713: 679: 666: 648: 643: 642: 629:total curvature 625: 623:Total curvature 597: 586: 585: 565:-planes in the 509: 481: 476: 475: 429: 401: 396: 395: 347: 342: 341: 297: 286: 280: 277: 262: 246: 235: 233:Generalizations 131:Euclidean space 87: 76: 70: 67: 56: 42:related reading 32: 28: 21: 12: 11: 5: 1175: 1173: 1165: 1164: 1159: 1154: 1149: 1144: 1134: 1133: 1127: 1126: 1124: 1123: 1110: 1107: 1106: 1104: 1103: 1098: 1093: 1088: 1086:Gaussian units 1083: 1078: 1073: 1068: 1063: 1061:Gauss's method 1058: 1056:Gauss notation 1053: 1048: 1042: 1039: 1038: 1033: 1031: 1030: 1023: 1016: 1008: 1002: 1001: 988: 973: 952: 951:External links 949: 948: 947: 940: 919:online version 911: 906:Gauss, K. F., 904: 899:Gauss, K. F., 895: 892: 880: 879: 872: 865: 838:parabolic line 825: 822: 799: 796: 790: 785: 781: 777: 774: 771: 767: 764: 757: 751: 747: 743: 738: 734: 729: 725: 720: 716: 712: 709: 706: 702: 699: 692: 686: 682: 678: 673: 669: 664: 660: 655: 651: 624: 621: 606: 601: 596: 593: 567:tangent bundle 522: 519: 516: 512: 508: 503: 500: 497: 490: 487: 457: 454: 451: 448: 445: 438: 435: 428: 423: 420: 417: 410: 407: 369: 366: 363: 356: 353: 315: âŠ†  299: 298: 249: 247: 240: 234: 231: 227:linking number 213:shape operator 89: 88: 46:external links 35: 33: 26: 13: 10: 9: 6: 4: 3: 2: 1174: 1163: 1160: 1158: 1155: 1153: 1150: 1148: 1145: 1143: 1140: 1139: 1137: 1122: 1121: 1112: 1111: 1108: 1102: 1099: 1097: 1094: 1092: 1089: 1087: 1084: 1082: 1079: 1077: 1074: 1072: 1069: 1067: 1064: 1062: 1059: 1057: 1054: 1052: 1049: 1047: 1044: 1043: 1040: 1036: 1029: 1024: 1022: 1017: 1015: 1010: 1009: 1006: 991: 989:0-273-08536-0 985: 981: 980: 974: 969: 968: 963: 960: 955: 954: 950: 945: 941: 939: 935: 931: 927: 923: 920: 916: 912: 909: 905: 902: 898: 897: 893: 891: 889: 885: 884:elliptic cusp 877: 873: 870: 866: 863: 862: 861: 859: 858:Clint McCrory 855: 851: 847: 843: 839: 830: 823: 821: 819: 815: 810: 797: 794: 788: 783: 779: 775: 772: 769: 765: 762: 749: 745: 741: 736: 732: 723: 718: 714: 710: 707: 704: 700: 697: 684: 680: 676: 671: 667: 658: 653: 649: 640: 638: 634: 630: 622: 620: 604: 594: 591: 583: 579: 575: 571: 568: 564: 560: 556: 553:of dimension 552: 549: 545: 542:of dimension 541: 536: 520: 517: 514: 510: 506: 501: 498: 495: 485: 473: 455: 452: 449: 446: 443: 433: 426: 421: 418: 415: 405: 393: 389: 385: 367: 364: 361: 351: 340: 337: 333: 329: 325: 320: 318: 314: 310: 306: 305:hypersurfaces 295: 292: 284: 274: 270: 266: 260: 259: 255: 250:This section 248: 244: 239: 238: 232: 230: 228: 224: 219: 216: 214: 210: 206: 202: 198: 194: 190: 185: 183: 182:Carl F. Gauss 179: 175: 171: 167: 163: 159: 155: 151: 147: 143: 139: 135: 132: 128: 124: 120: 116: 112: 108: 104: 95: 85: 82: 74: 64: 60: 54: 53: 47: 43: 39: 34: 25: 24: 19: 1118: 1050: 993:. Retrieved 978: 965: 943: 914: 907: 900: 887: 883: 881: 835: 820:properties. 811: 641: 628: 626: 581: 573: 569: 562: 558: 554: 550: 543: 539: 537: 391: 387: 383: 339:Grassmannian 335: 331: 323: 321: 316: 312: 308: 302: 287: 278: 263:Please help 251: 220: 217: 209:differential 195:is half the 186: 177: 173: 169: 165: 161: 157: 149: 145: 141: 137: 133: 126: 106: 100: 77: 68: 57:Please help 49: 1096:Gauss's law 962:"Gauss Map" 944:Solid Shape 818:topological 386:-planes in 328:submanifold 154:unit sphere 119:unit vector 63:introducing 1136:Categories 894:References 207:, and the 189:orientable 123:orthogonal 1051:Gauss map 967:MathWorld 780:∬ 742:× 715:∬ 677:× 659:± 650:∬ 518:− 507:≅ 489:~ 447:− 437:~ 427:≅ 409:~ 355:~ 252:does not 107:Gauss map 71:July 2011 1157:Surfaces 1120:Category 934:Archived 922:Archived 336:oriented 281:May 2020 201:Jacobian 121:that is 115:function 995:4 March 635:of the 273:removed 258:sources 152:is the 148:(where 111:surface 59:improve 986:  903:(1827) 792:  760:  695:  392:normal 193:degree 105:, the 869:ridge 846:cusps 576:is a 113:is a 109:of a 44:, or 997:2016 984:ISBN 886:and 856:and 812:The 256:any 254:cite 223:link 330:of 307:in 267:by 176:at 160:in 129:in 101:In 1138:: 964:. 890:. 867:A 852:, 582:TM 570:TM 319:. 229:. 215:. 184:. 144:→ 140:: 48:, 40:, 1027:e 1020:t 1013:v 999:. 970:. 798:A 795:d 789:K 784:S 776:= 773:v 770:d 766:u 763:d 756:| 750:v 746:X 737:u 733:X 728:| 724:K 719:R 711:= 708:v 705:d 701:u 698:d 691:| 685:v 681:N 672:u 668:N 663:| 654:R 605:n 600:R 595:= 592:M 574:N 563:k 559:X 555:n 551:M 544:k 540:X 521:1 515:n 511:S 502:n 499:, 496:1 486:G 456:n 453:, 450:k 444:n 434:G 422:n 419:, 416:k 406:G 388:R 384:k 368:n 365:, 362:k 352:G 332:R 326:- 324:k 317:R 313:S 309:R 294:) 288:( 283:) 279:( 275:. 261:. 178:p 174:X 170:p 168:( 166:N 162:X 158:p 150:S 146:S 142:X 138:N 134:R 127:X 84:) 78:( 73:) 69:( 55:. 20:.

Index

Gauss map (disambiguation)
list of references
related reading
external links
inline citations
improve
introducing
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differential geometry
surface
function
unit vector
orthogonal
Euclidean space
unit sphere
Carl F. Gauss
orientable
degree
Euler characteristic
Jacobian
Gaussian curvature
differential
shape operator
link
linking number

cite
sources
improve this section

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