Knowledge (XXG)

Second fundamental form

Source 📝

98: 2715: 1208: 2413: 2488: 1026: 1050: 1996: 2237: 1458: 682: 2710:{\displaystyle \langle R_{N}(u,v)w,z\rangle =\langle R_{M}(u,v)w,z\rangle +\langle \mathrm {I} \!\mathrm {I} (u,z),\mathrm {I} \!\mathrm {I} (v,w)\rangle -\langle \mathrm {I} \!\mathrm {I} (u,w),\mathrm {I} \!\mathrm {I} (v,z)\rangle \,.} 284: 1664: 1538: 913: 1203:{\displaystyle L=-\mathbf {r} _{u}\cdot \mathbf {H} \cdot \mathbf {r} _{u}\,,\quad M=-\mathbf {r} _{u}\cdot \mathbf {H} \cdot \mathbf {r} _{v}\,,\quad N=-\mathbf {r} _{v}\cdot \mathbf {H} \cdot \mathbf {r} _{v}\,.} 1756: 1859: 866: 781: 2135: 2408:{\displaystyle \langle R(u,v)w,z\rangle =\langle \mathrm {I} \!\mathrm {I} (u,z),\mathrm {I} \!\mathrm {I} (v,w)\rangle -\langle \mathrm {I} \!\mathrm {I} (u,w),\mathrm {I} \!\mathrm {I} (v,z)\rangle .} 1362: 586: 386: 2181: 71: 2214: 1806: 1830: 1779: 199: 3074: 1594: 1469: 1021:{\displaystyle L=\mathbf {r} _{uu}\cdot \mathbf {n} \,,\quad M=\mathbf {r} _{uv}\cdot \mathbf {n} \,,\quad N=\mathbf {r} _{vv}\cdot \mathbf {n} \,.} 1991:{\displaystyle \mathrm {I} \!\mathrm {I} (v,w)=\langle S(v),w\rangle n=-\langle \nabla _{v}n,w\rangle n=\langle n,\nabla _{v}w\rangle n\,,} 1684: 2860: 814: 693: 2907: 2995: 2932: 2811: 2792: 2773: 2066: 40: 2040:(which is called a co-orientation of the hypersurface - for surfaces in Euclidean space, this is equivalently given by a choice of 3084: 2882: 1833: 3069: 2832: 1453:{\displaystyle \mathbf {n} ={\frac {\mathbf {r} _{1}\times \mathbf {r} _{2}}{|\mathbf {r} _{1}\times \mathbf {r} _{2}|}}\,.} 677:{\displaystyle \mathbf {n} ={\frac {\mathbf {r} _{u}\times \mathbf {r} _{v}}{|\mathbf {r} _{u}\times \mathbf {r} _{v}|}}\,.} 3079: 2962: 2736: 310: 130: 2902: 2420: 1809: 2838: 3025: 3000: 2922: 2224: 1032: 2853: 2143: 1843:
More generally, on a Riemannian manifold, the second fundamental form is an equivalent way to describe the
1350:
is a nonzero vector normal to the surface. The parametrization thus defines a field of unit normal vectors
574:
is a nonzero vector normal to the surface. The parametrization thus defines a field of unit normal vectors
2977: 2967: 2746: 2726: 1259: 462: 74: 2874: 2751: 20: 2828: 2184: 2014: 126: 50: 3015: 2987: 2942: 2438: 86: 78: 2189: 2947: 2897: 2846: 2731: 170: 111: 2807: 2788: 2769: 2425: 2024: 1544: 3089: 3010: 2912: 279:{\displaystyle z=L{\frac {x^{2}}{2}}+Mxy+N{\frac {y^{2}}{2}}+{\text{higher order terms}}\,,} 186: 1788: 3005: 2917: 2220: 1815: 1764: 1675: 44: 97: 3038: 3033: 2952: 2741: 2028: 1844: 1036: 430:
The second fundamental form of a general parametric surface is defined as follows. Let
302: 32: 3063: 2957: 2829:
Geometry of the Second Fundamental Form: Curvature Properties and Variational Aspects
2057: 2041: 1837: 1332: 552: 36: 2431:
For general Riemannian manifolds one has to add the curvature of ambient space; if
1659:{\displaystyle b_{\alpha \beta }=r_{,\alpha \beta }^{\ \ \,\gamma }n_{\gamma }\,.} 3043: 2228: 2053: 904: 82: 1533:{\displaystyle \mathrm {I\!I} =b_{\alpha \beta }\,du^{\alpha }\,du^{\beta }\,.} 2056:. In that case it is a quadratic form on the tangent space with values in the 2034:
The sign of the second fundamental form depends on the choice of direction of
2892: 2870: 1782: 2467:
with induced metric can be expressed using the second fundamental form and
3048: 1570:-plane are given by the projections of the second partial derivatives of 891:-plane are given by the projections of the second partial derivatives of 81:. More generally, such a quadratic form is defined for a smooth immersed 1044:, the second fundamental form coefficients can be computed as follows: 160: 1751:{\displaystyle \mathrm {I\!I} (v,w)=-\langle d\nu (v),w\rangle \nu } 1262:
of two variables. It is common to denote the partial derivatives of
465:
of two variables. It is common to denote the partial derivatives of
96: 861:{\displaystyle {\begin{bmatrix}L&M\\M&N\end{bmatrix}}\,.} 776:{\displaystyle \mathrm {I\!I} =L\,du^{2}+2M\,du\,dv+N\,dv^{2}\,,} 289:
and the second fundamental form at the origin in the coordinates
2804:
A Comprehensive introduction to differential geometry (Volume 3)
2842: 77:, it serves to define extrinsic invariants of the surface, its 2130:{\displaystyle \mathrm {I\!I} (v,w)=(\nabla _{v}w)^{\bot }\,,} 2052:
The second fundamental form can be generalized to arbitrary
1218:
The second fundamental form of a general parametric surface
422:, and define the second fundamental form in the same way. 403:, one can choose the coordinate system so that the plane 129:. First suppose that the surface is the graph of a twice 2023:
a field of normal vectors on the hypersurface. (If the
2764:
Guggenheimer, Heinrich (1977). "Chapter 10. Surfaces".
823: 2491: 2424:, as it may be viewed as a generalization of Gauss's 2240: 2192: 2146: 2069: 1862: 1818: 1791: 1767: 1687: 1597: 1472: 1365: 1053: 916: 817: 696: 589: 313: 202: 53: 3024: 2986: 2931: 2881: 2783:Kobayashi, Shoshichi & Nomizu, Katsumi (1996). 2709: 2407: 2208: 2175: 2129: 2031:, then the second fundamental form is symmetric.) 1990: 1824: 1800: 1773: 1750: 1658: 1582:and can be computed in terms of the normal vector 1532: 1463:The second fundamental form is usually written as 1452: 1202: 1020: 860: 775: 687:The second fundamental form is usually written as 676: 380: 278: 65: 2679: 2650: 2615: 2586: 2378: 2349: 2314: 2285: 2074: 1868: 1692: 1477: 701: 381:{\displaystyle L\,dx^{2}+2M\,dx\,dy+N\,dy^{2}\,.} 58: 16:Quadratic form related to curvatures of surfaces 1289:. Regularity of the parametrization means that 505:. Regularity of the parametrization means that 2854: 1246:be a regular parametrization of a surface in 449:be a regular parametrization of a surface in 8: 2785:Foundations of Differential Geometry, Vol. 2 2700: 2642: 2636: 2578: 2572: 2535: 2529: 2492: 2399: 2341: 2335: 2277: 2271: 2241: 1978: 1956: 1947: 1925: 1913: 1892: 1742: 1718: 2231:can be described by the following formula: 2861: 2847: 2839: 1678:, the second fundamental form is given by 2703: 2680: 2674: 2651: 2645: 2616: 2610: 2587: 2581: 2542: 2499: 2490: 2379: 2373: 2350: 2344: 2315: 2309: 2286: 2280: 2239: 2197: 2191: 2167: 2154: 2145: 2123: 2117: 2104: 2070: 2068: 1984: 1969: 1932: 1869: 1863: 1861: 1817: 1790: 1766: 1688: 1686: 1652: 1646: 1636: 1629: 1618: 1602: 1596: 1526: 1520: 1512: 1506: 1498: 1489: 1473: 1471: 1446: 1438: 1432: 1427: 1417: 1412: 1406: 1398: 1393: 1383: 1378: 1374: 1366: 1364: 1196: 1190: 1185: 1176: 1167: 1162: 1147: 1141: 1136: 1127: 1118: 1113: 1098: 1092: 1087: 1078: 1069: 1064: 1052: 1014: 1009: 997: 992: 980: 975: 963: 958: 946: 941: 929: 924: 915: 854: 818: 816: 769: 763: 755: 742: 735: 720: 712: 697: 695: 670: 662: 656: 651: 641: 636: 630: 622: 617: 607: 602: 598: 590: 588: 374: 368: 360: 347: 340: 325: 317: 312: 272: 267: 253: 247: 218: 212: 201: 54: 52: 903:and can be computed with the aid of the 2048:Generalization to arbitrary codimension 2176:{\displaystyle (\nabla _{v}w)^{\bot }} 1576:at that point onto the normal line to 1325:, and hence span the tangent plane to 897:at that point onto the normal line to 545:, and hence span the tangent plane to 193:at (0,0) starts with quadratic terms: 2183:denotes the orthogonal projection of 1670:Hypersurface in a Riemannian manifold 101:Definition of second fundamental form 7: 2787:(New ed.). Wiley-Interscience. 1561:at a given point in the parametric 885:at a given point in the parametric 163:to the surface at the origin. Then 2908:Radius of curvature (applications) 2681: 2675: 2652: 2646: 2617: 2611: 2588: 2582: 2380: 2374: 2351: 2345: 2316: 2310: 2287: 2281: 2194: 2168: 2151: 2118: 2101: 2075: 2071: 1966: 1929: 1870: 1864: 1693: 1689: 1478: 1474: 702: 698: 59: 55: 14: 3075:Differential geometry of surfaces 2996:Curvature of Riemannian manifolds 1331:at each point. Equivalently, the 1307:are linearly independent for any 551:at each point. Equivalently, the 527:are linearly independent for any 110:The second fundamental form of a 1428: 1413: 1394: 1379: 1367: 1186: 1177: 1163: 1137: 1128: 1114: 1088: 1079: 1065: 1010: 993: 976: 959: 942: 925: 652: 637: 618: 603: 591: 185:vanish at (0,0). Therefore, the 73:(read "two"). Together with the 1834:vector-valued differential form 1151: 1102: 984: 950: 66:{\displaystyle \mathrm {I\!I} } 2833:Katholieke Universiteit Leuven 2697: 2685: 2668: 2656: 2633: 2621: 2604: 2592: 2560: 2548: 2517: 2505: 2396: 2384: 2367: 2355: 2332: 2320: 2303: 2291: 2259: 2247: 2164: 2147: 2114: 2097: 2091: 2079: 1904: 1898: 1886: 1874: 1836:, and the brackets denote the 1733: 1727: 1709: 1697: 1439: 1407: 663: 631: 125:was introduced and studied by 1: 1545:Einstein summation convention 2437:is a manifold embedded in a 2209:{\displaystyle \nabla _{v}w} 2017:of the ambient manifold and 1543:The equation above uses the 131:continuously differentiable 3106: 2476:, the curvature tensor of 2452:then the curvature tensor 2060:and it can be defined by 43:in the three-dimensional 3026:Curvature of connections 3001:Riemann curvature tensor 2923:Total absolute curvature 2802:Spivak, Michael (1999). 2216:onto the normal bundle. 1213: 808:of the tangent plane is 786:its matrix in the basis 3085:Curvature (mathematics) 2973:Second fundamental form 2963:Gauss–Codazzi equations 2827:Steven Verpoort (2008) 2737:Gauss–Codazzi equations 1224:is defined as follows. 25:second fundamental form 2978:Third fundamental form 2968:First fundamental form 2933:Differential geometry 2903:Frenet–Serret formulas 2883:Differential geometry 2747:Third fundamental form 2727:First fundamental form 2711: 2409: 2210: 2177: 2131: 1992: 1826: 1802: 1775: 1752: 1660: 1534: 1454: 1260:vector-valued function 1204: 1022: 862: 777: 678: 463:vector-valued function 382: 280: 102: 75:first fundamental form 67: 3070:Differential geometry 2875:differential geometry 2806:. Publish or Perish. 2766:Differential Geometry 2752:Tautological one-form 2712: 2410: 2211: 2178: 2132: 1993: 1853:) of a hypersurface, 1827: 1803: 1801:{\displaystyle d\nu } 1776: 1753: 1661: 1535: 1455: 1205: 1033:signed distance field 1023: 863: 778: 679: 383: 281: 152:, and that the plane 100: 68: 47:, usually denoted by 21:differential geometry 2943:Principal curvatures 2489: 2238: 2190: 2185:covariant derivative 2144: 2067: 2015:covariant derivative 1860: 1840:of Euclidean space. 1825:{\displaystyle \nu } 1816: 1789: 1774:{\displaystyle \nu } 1765: 1685: 1595: 1470: 1363: 1214:Physicist's notation 1051: 914: 815: 694: 587: 311: 200: 79:principal curvatures 51: 3080:Riemannian geometry 3016:Sectional curvature 2988:Riemannian geometry 2869:Various notions of 2439:Riemannian manifold 2418:This is called the 1641: 391:For a smooth point 171:partial derivatives 87:Riemannian manifold 2948:Gaussian curvature 2898:Torsion of a curve 2732:Gaussian curvature 2707: 2405: 2206: 2173: 2127: 1988: 1822: 1798: 1771: 1748: 1656: 1614: 1530: 1450: 1200: 1018: 858: 848: 773: 674: 426:Classical notation 378: 276: 269:higher order terms 112:parametric surface 103: 63: 3057: 3056: 2426:Theorema Egregium 2044:of the surface). 2025:affine connection 1635: 1632: 1550:The coefficients 1444: 1319:in the domain of 871:The coefficients 668: 539:in the domain of 270: 262: 227: 3097: 3011:Scalar curvature 2913:Affine curvature 2863: 2856: 2849: 2840: 2817: 2798: 2779: 2716: 2714: 2713: 2708: 2684: 2678: 2655: 2649: 2620: 2614: 2591: 2585: 2547: 2546: 2504: 2503: 2481: 2475: 2466: 2460: 2451: 2436: 2414: 2412: 2411: 2406: 2383: 2377: 2354: 2348: 2319: 2313: 2290: 2284: 2225:curvature tensor 2215: 2213: 2212: 2207: 2202: 2201: 2182: 2180: 2179: 2174: 2172: 2171: 2159: 2158: 2136: 2134: 2133: 2128: 2122: 2121: 2109: 2108: 2078: 2039: 2022: 2012: 1997: 1995: 1994: 1989: 1974: 1973: 1937: 1936: 1873: 1867: 1852: 1831: 1829: 1828: 1823: 1807: 1805: 1804: 1799: 1780: 1778: 1777: 1772: 1757: 1755: 1754: 1749: 1696: 1665: 1663: 1662: 1657: 1651: 1650: 1640: 1633: 1630: 1628: 1610: 1609: 1587: 1581: 1575: 1569: 1560: 1539: 1537: 1536: 1531: 1525: 1524: 1511: 1510: 1497: 1496: 1481: 1459: 1457: 1456: 1451: 1445: 1443: 1442: 1437: 1436: 1431: 1422: 1421: 1416: 1410: 1404: 1403: 1402: 1397: 1388: 1387: 1382: 1375: 1370: 1355: 1349: 1330: 1324: 1318: 1306: 1297: 1288: 1284: 1273: 1268:with respect to 1267: 1257: 1251: 1245: 1223: 1209: 1207: 1206: 1201: 1195: 1194: 1189: 1180: 1172: 1171: 1166: 1146: 1145: 1140: 1131: 1123: 1122: 1117: 1097: 1096: 1091: 1082: 1074: 1073: 1068: 1043: 1027: 1025: 1024: 1019: 1013: 1005: 1004: 996: 979: 971: 970: 962: 945: 937: 936: 928: 902: 896: 890: 884: 867: 865: 864: 859: 853: 852: 807: 782: 780: 779: 774: 768: 767: 725: 724: 705: 683: 681: 680: 675: 669: 667: 666: 661: 660: 655: 646: 645: 640: 634: 628: 627: 626: 621: 612: 611: 606: 599: 594: 579: 573: 550: 544: 538: 526: 515: 504: 493: 482: 476: 471:with respect to 470: 460: 454: 448: 421: 415: 409: 402: 396: 387: 385: 384: 379: 373: 372: 330: 329: 300: 285: 283: 282: 277: 271: 268: 263: 258: 257: 248: 228: 223: 222: 213: 187:Taylor expansion 184: 178: 173:with respect to 168: 158: 151: 124: 118: 72: 70: 69: 64: 62: 3105: 3104: 3100: 3099: 3098: 3096: 3095: 3094: 3060: 3059: 3058: 3053: 3020: 3006:Ricci curvature 2982: 2934: 2927: 2918:Total curvature 2884: 2877: 2867: 2824: 2814: 2801: 2795: 2782: 2776: 2763: 2760: 2723: 2538: 2495: 2487: 2486: 2477: 2473: 2468: 2462: 2458: 2453: 2441: 2432: 2236: 2235: 2221:Euclidean space 2193: 2188: 2187: 2163: 2150: 2142: 2141: 2113: 2100: 2065: 2064: 2050: 2035: 2018: 2008: 2002: 1965: 1928: 1858: 1857: 1848: 1814: 1813: 1787: 1786: 1763: 1762: 1683: 1682: 1676:Euclidean space 1672: 1642: 1598: 1593: 1592: 1583: 1577: 1571: 1562: 1559: 1551: 1516: 1502: 1485: 1468: 1467: 1426: 1411: 1405: 1392: 1377: 1376: 1361: 1360: 1351: 1348: 1341: 1335: 1326: 1320: 1308: 1305: 1299: 1296: 1290: 1286: 1283: 1275: 1269: 1263: 1253: 1247: 1228: 1219: 1216: 1184: 1161: 1135: 1112: 1086: 1063: 1049: 1048: 1039: 991: 957: 923: 912: 911: 898: 892: 886: 872: 847: 846: 841: 835: 834: 829: 819: 813: 812: 805: 796: 787: 759: 716: 692: 691: 650: 635: 629: 616: 601: 600: 585: 584: 575: 572: 563: 555: 546: 540: 528: 525: 517: 514: 506: 503: 495: 492: 484: 478: 472: 466: 456: 450: 431: 428: 417: 411: 404: 398: 392: 364: 321: 309: 308: 290: 249: 214: 198: 197: 180: 174: 164: 153: 134: 120: 114: 108: 95: 49: 48: 45:Euclidean space 17: 12: 11: 5: 3103: 3101: 3093: 3092: 3087: 3082: 3077: 3072: 3062: 3061: 3055: 3054: 3052: 3051: 3046: 3041: 3039:Torsion tensor 3036: 3034:Curvature form 3030: 3028: 3022: 3021: 3019: 3018: 3013: 3008: 3003: 2998: 2992: 2990: 2984: 2983: 2981: 2980: 2975: 2970: 2965: 2960: 2955: 2953:Mean curvature 2950: 2945: 2939: 2937: 2929: 2928: 2926: 2925: 2920: 2915: 2910: 2905: 2900: 2895: 2889: 2887: 2879: 2878: 2868: 2866: 2865: 2858: 2851: 2843: 2837: 2836: 2823: 2822:External links 2820: 2819: 2818: 2812: 2799: 2793: 2780: 2774: 2759: 2756: 2755: 2754: 2749: 2744: 2742:Shape operator 2739: 2734: 2729: 2722: 2719: 2718: 2717: 2706: 2702: 2699: 2696: 2693: 2690: 2687: 2683: 2677: 2673: 2670: 2667: 2664: 2661: 2658: 2654: 2648: 2644: 2641: 2638: 2635: 2632: 2629: 2626: 2623: 2619: 2613: 2609: 2606: 2603: 2600: 2597: 2594: 2590: 2584: 2580: 2577: 2574: 2571: 2568: 2565: 2562: 2559: 2556: 2553: 2550: 2545: 2541: 2537: 2534: 2531: 2528: 2525: 2522: 2519: 2516: 2513: 2510: 2507: 2502: 2498: 2494: 2471: 2456: 2421:Gauss equation 2416: 2415: 2404: 2401: 2398: 2395: 2392: 2389: 2386: 2382: 2376: 2372: 2369: 2366: 2363: 2360: 2357: 2353: 2347: 2343: 2340: 2337: 2334: 2331: 2328: 2325: 2322: 2318: 2312: 2308: 2305: 2302: 2299: 2296: 2293: 2289: 2283: 2279: 2276: 2273: 2270: 2267: 2264: 2261: 2258: 2255: 2252: 2249: 2246: 2243: 2205: 2200: 2196: 2170: 2166: 2162: 2157: 2153: 2149: 2138: 2137: 2126: 2120: 2116: 2112: 2107: 2103: 2099: 2096: 2093: 2090: 2087: 2084: 2081: 2077: 2073: 2049: 2046: 2004: 1999: 1998: 1987: 1983: 1980: 1977: 1972: 1968: 1964: 1961: 1958: 1955: 1952: 1949: 1946: 1943: 1940: 1935: 1931: 1927: 1924: 1921: 1918: 1915: 1912: 1909: 1906: 1903: 1900: 1897: 1894: 1891: 1888: 1885: 1882: 1879: 1876: 1872: 1866: 1845:shape operator 1832:regarded as a 1821: 1797: 1794: 1770: 1759: 1758: 1747: 1744: 1741: 1738: 1735: 1732: 1729: 1726: 1723: 1720: 1717: 1714: 1711: 1708: 1705: 1702: 1699: 1695: 1691: 1671: 1668: 1667: 1666: 1655: 1649: 1645: 1639: 1627: 1624: 1621: 1617: 1613: 1608: 1605: 1601: 1555: 1541: 1540: 1529: 1523: 1519: 1515: 1509: 1505: 1501: 1495: 1492: 1488: 1484: 1480: 1476: 1461: 1460: 1449: 1441: 1435: 1430: 1425: 1420: 1415: 1409: 1401: 1396: 1391: 1386: 1381: 1373: 1369: 1346: 1339: 1303: 1294: 1279: 1215: 1212: 1211: 1210: 1199: 1193: 1188: 1183: 1179: 1175: 1170: 1165: 1160: 1157: 1154: 1150: 1144: 1139: 1134: 1130: 1126: 1121: 1116: 1111: 1108: 1105: 1101: 1095: 1090: 1085: 1081: 1077: 1072: 1067: 1062: 1059: 1056: 1029: 1028: 1017: 1012: 1008: 1003: 1000: 995: 990: 987: 983: 978: 974: 969: 966: 961: 956: 953: 949: 944: 940: 935: 932: 927: 922: 919: 869: 868: 857: 851: 845: 842: 840: 837: 836: 833: 830: 828: 825: 824: 822: 801: 792: 784: 783: 772: 766: 762: 758: 754: 751: 748: 745: 741: 738: 734: 731: 728: 723: 719: 715: 711: 708: 704: 700: 685: 684: 673: 665: 659: 654: 649: 644: 639: 633: 625: 620: 615: 610: 605: 597: 593: 568: 559: 521: 510: 499: 488: 427: 424: 410:is tangent to 389: 388: 377: 371: 367: 363: 359: 356: 353: 350: 346: 343: 339: 336: 333: 328: 324: 320: 316: 303:quadratic form 287: 286: 275: 266: 261: 256: 252: 246: 243: 240: 237: 234: 231: 226: 221: 217: 211: 208: 205: 107: 104: 94: 91: 61: 57: 41:smooth surface 33:quadratic form 15: 13: 10: 9: 6: 4: 3: 2: 3102: 3091: 3088: 3086: 3083: 3081: 3078: 3076: 3073: 3071: 3068: 3067: 3065: 3050: 3047: 3045: 3042: 3040: 3037: 3035: 3032: 3031: 3029: 3027: 3023: 3017: 3014: 3012: 3009: 3007: 3004: 3002: 2999: 2997: 2994: 2993: 2991: 2989: 2985: 2979: 2976: 2974: 2971: 2969: 2966: 2964: 2961: 2959: 2958:Darboux frame 2956: 2954: 2951: 2949: 2946: 2944: 2941: 2940: 2938: 2936: 2930: 2924: 2921: 2919: 2916: 2914: 2911: 2909: 2906: 2904: 2901: 2899: 2896: 2894: 2891: 2890: 2888: 2886: 2880: 2876: 2872: 2864: 2859: 2857: 2852: 2850: 2845: 2844: 2841: 2834: 2830: 2826: 2825: 2821: 2815: 2813:0-914098-72-1 2809: 2805: 2800: 2796: 2794:0-471-15732-5 2790: 2786: 2781: 2777: 2775:0-486-63433-7 2771: 2767: 2762: 2761: 2757: 2753: 2750: 2748: 2745: 2743: 2740: 2738: 2735: 2733: 2730: 2728: 2725: 2724: 2720: 2704: 2694: 2691: 2688: 2671: 2665: 2662: 2659: 2639: 2630: 2627: 2624: 2607: 2601: 2598: 2595: 2575: 2569: 2566: 2563: 2557: 2554: 2551: 2543: 2539: 2532: 2526: 2523: 2520: 2514: 2511: 2508: 2500: 2496: 2485: 2484: 2483: 2480: 2474: 2465: 2459: 2449: 2445: 2440: 2435: 2429: 2427: 2423: 2422: 2402: 2393: 2390: 2387: 2370: 2364: 2361: 2358: 2338: 2329: 2326: 2323: 2306: 2300: 2297: 2294: 2274: 2268: 2265: 2262: 2256: 2253: 2250: 2244: 2234: 2233: 2232: 2230: 2226: 2222: 2217: 2203: 2198: 2186: 2160: 2155: 2124: 2110: 2105: 2094: 2088: 2085: 2082: 2063: 2062: 2061: 2059: 2058:normal bundle 2055: 2047: 2045: 2043: 2038: 2032: 2030: 2026: 2021: 2016: 2011: 2007: 1985: 1981: 1975: 1970: 1962: 1959: 1953: 1950: 1944: 1941: 1938: 1933: 1922: 1919: 1916: 1910: 1907: 1901: 1895: 1889: 1883: 1880: 1877: 1856: 1855: 1854: 1851: 1846: 1841: 1839: 1838:metric tensor 1835: 1819: 1811: 1795: 1792: 1784: 1768: 1745: 1739: 1736: 1730: 1724: 1721: 1715: 1712: 1706: 1703: 1700: 1681: 1680: 1679: 1677: 1669: 1653: 1647: 1643: 1637: 1625: 1622: 1619: 1615: 1611: 1606: 1603: 1599: 1591: 1590: 1589: 1586: 1580: 1574: 1568: 1565: 1558: 1554: 1548: 1546: 1527: 1521: 1517: 1513: 1507: 1503: 1499: 1493: 1490: 1486: 1482: 1466: 1465: 1464: 1447: 1433: 1423: 1418: 1399: 1389: 1384: 1371: 1359: 1358: 1357: 1354: 1345: 1338: 1334: 1333:cross product 1329: 1323: 1316: 1312: 1302: 1293: 1282: 1278: 1272: 1266: 1261: 1256: 1250: 1243: 1239: 1235: 1231: 1225: 1222: 1197: 1191: 1181: 1173: 1168: 1158: 1155: 1152: 1148: 1142: 1132: 1124: 1119: 1109: 1106: 1103: 1099: 1093: 1083: 1075: 1070: 1060: 1057: 1054: 1047: 1046: 1045: 1042: 1038: 1034: 1015: 1006: 1001: 998: 988: 985: 981: 972: 967: 964: 954: 951: 947: 938: 933: 930: 920: 917: 910: 909: 908: 906: 901: 895: 889: 883: 879: 875: 855: 849: 843: 838: 831: 826: 820: 811: 810: 809: 804: 800: 795: 791: 770: 764: 760: 756: 752: 749: 746: 743: 739: 736: 732: 729: 726: 721: 717: 713: 709: 706: 690: 689: 688: 671: 657: 647: 642: 623: 613: 608: 595: 583: 582: 581: 578: 571: 567: 562: 558: 554: 553:cross product 549: 543: 536: 532: 524: 520: 513: 509: 502: 498: 491: 487: 481: 475: 469: 464: 459: 453: 446: 442: 438: 434: 425: 423: 420: 414: 407: 401: 395: 375: 369: 365: 361: 357: 354: 351: 348: 344: 341: 337: 334: 331: 326: 322: 318: 314: 307: 306: 305: 304: 298: 294: 273: 264: 259: 254: 250: 244: 241: 238: 235: 232: 229: 224: 219: 215: 209: 206: 203: 196: 195: 194: 192: 188: 183: 177: 172: 167: 162: 156: 149: 145: 141: 137: 132: 128: 123: 117: 113: 105: 99: 92: 90: 88: 84: 80: 76: 46: 42: 38: 37:tangent plane 34: 30: 26: 22: 2972: 2803: 2784: 2765: 2478: 2469: 2463: 2454: 2447: 2443: 2433: 2430: 2419: 2417: 2218: 2139: 2051: 2036: 2033: 2029:torsion-free 2019: 2013:denotes the 2009: 2005: 2000: 1849: 1847:(denoted by 1842: 1810:differential 1760: 1673: 1588:as follows: 1584: 1578: 1572: 1566: 1563: 1556: 1552: 1549: 1542: 1462: 1352: 1343: 1336: 1327: 1321: 1314: 1310: 1300: 1291: 1280: 1276: 1270: 1264: 1258:is a smooth 1254: 1248: 1241: 1237: 1233: 1229: 1226: 1220: 1217: 1040: 1030: 907:as follows: 899: 893: 887: 881: 877: 873: 870: 802: 798: 793: 789: 785: 686: 576: 569: 565: 560: 556: 547: 541: 534: 530: 522: 518: 511: 507: 500: 496: 489: 485: 479: 473: 467: 461:is a smooth 457: 451: 444: 440: 436: 432: 429: 418: 412: 405: 399: 393: 390: 296: 292: 288: 190: 181: 175: 165: 154: 147: 143: 139: 135: 121: 115: 109: 93:Surface in R 29:shape tensor 28: 24: 18: 3044:Cocurvature 2935:of surfaces 2873:defined in 2229:submanifold 2054:codimension 2042:orientation 905:dot product 83:submanifold 3064:Categories 2758:References 133:function, 106:Motivation 2893:Curvature 2885:of curves 2871:curvature 2768:. Dover. 2701:⟩ 2643:⟨ 2640:− 2637:⟩ 2579:⟨ 2573:⟩ 2536:⟨ 2530:⟩ 2493:⟨ 2400:⟩ 2342:⟨ 2339:− 2336:⟩ 2278:⟨ 2272:⟩ 2242:⟨ 2195:∇ 2169:⊥ 2152:∇ 2119:⊥ 2102:∇ 1979:⟩ 1967:∇ 1957:⟨ 1948:⟩ 1930:∇ 1926:⟨ 1923:− 1914:⟩ 1893:⟨ 1820:ν 1796:ν 1783:Gauss map 1769:ν 1746:ν 1743:⟩ 1725:ν 1719:⟨ 1716:− 1648:γ 1638:γ 1626:β 1623:α 1607:β 1604:α 1522:β 1508:α 1494:β 1491:α 1424:× 1390:× 1182:⋅ 1174:⋅ 1159:− 1133:⋅ 1125:⋅ 1110:− 1084:⋅ 1076:⋅ 1061:− 1007:⋅ 973:⋅ 939:⋅ 648:× 614:× 3049:Holonomy 2721:See also 1287:α = 1, 2 1252:, where 455:, where 169:and its 3090:Tensors 1781:is the 1037:Hessian 301:is the 161:tangent 35:on the 31:) is a 2810:  2791:  2772:  2223:, the 2140:where 2001:where 1785:, and 1761:where 1634:  1631:  1031:For a 23:, the 2831:from 2227:of a 127:Gauss 85:in a 39:of a 2808:ISBN 2789:ISBN 2770:ISBN 1808:the 1298:and 1227:Let 516:and 494:and 477:and 179:and 27:(or 2461:of 2219:In 2027:is 1812:of 1674:In 1274:by 1035:of 483:by 416:at 408:= 0 397:on 189:of 159:is 157:= 0 119:in 19:In 3066:: 2482:: 2428:. 1557:αÎČ 1547:. 1356:: 1342:× 1285:, 1232:= 888:uv 880:, 876:, 797:, 580:: 564:× 435:= 138:= 89:. 2862:e 2855:t 2848:v 2835:. 2816:. 2797:. 2778:. 2705:. 2698:) 2695:z 2692:, 2689:v 2686:( 2682:I 2676:I 2672:, 2669:) 2666:w 2663:, 2660:u 2657:( 2653:I 2647:I 2634:) 2631:w 2628:, 2625:v 2622:( 2618:I 2612:I 2608:, 2605:) 2602:z 2599:, 2596:u 2593:( 2589:I 2583:I 2576:+ 2570:z 2567:, 2564:w 2561:) 2558:v 2555:, 2552:u 2549:( 2544:M 2540:R 2533:= 2527:z 2524:, 2521:w 2518:) 2515:v 2512:, 2509:u 2506:( 2501:N 2497:R 2479:M 2472:M 2470:R 2464:N 2457:N 2455:R 2450:) 2448:g 2446:, 2444:M 2442:( 2434:N 2403:. 2397:) 2394:z 2391:, 2388:v 2385:( 2381:I 2375:I 2371:, 2368:) 2365:w 2362:, 2359:u 2356:( 2352:I 2346:I 2333:) 2330:w 2327:, 2324:v 2321:( 2317:I 2311:I 2307:, 2304:) 2301:z 2298:, 2295:u 2292:( 2288:I 2282:I 2275:= 2269:z 2266:, 2263:w 2260:) 2257:v 2254:, 2251:u 2248:( 2245:R 2204:w 2199:v 2165:) 2161:w 2156:v 2148:( 2125:, 2115:) 2111:w 2106:v 2098:( 2095:= 2092:) 2089:w 2086:, 2083:v 2080:( 2076:I 2072:I 2037:n 2020:n 2010:w 2006:v 2003:∇ 1986:, 1982:n 1976:w 1971:v 1963:, 1960:n 1954:= 1951:n 1945:w 1942:, 1939:n 1934:v 1920:= 1917:n 1911:w 1908:, 1905:) 1902:v 1899:( 1896:S 1890:= 1887:) 1884:w 1881:, 1878:v 1875:( 1871:I 1865:I 1850:S 1793:d 1740:w 1737:, 1734:) 1731:v 1728:( 1722:d 1713:= 1710:) 1707:w 1704:, 1701:v 1698:( 1694:I 1690:I 1654:. 1644:n 1620:, 1616:r 1612:= 1600:b 1585:n 1579:S 1573:r 1567:u 1564:u 1553:b 1528:. 1518:u 1514:d 1504:u 1500:d 1487:b 1483:= 1479:I 1475:I 1448:. 1440:| 1434:2 1429:r 1419:1 1414:r 1408:| 1400:2 1395:r 1385:1 1380:r 1372:= 1368:n 1353:n 1347:2 1344:r 1340:1 1337:r 1328:S 1322:r 1317:) 1315:u 1313:, 1311:u 1309:( 1304:2 1301:r 1295:1 1292:r 1281:α 1277:r 1271:u 1265:r 1255:r 1249:R 1244:) 1242:u 1240:, 1238:u 1236:( 1234:r 1230:r 1221:S 1198:. 1192:v 1187:r 1178:H 1169:v 1164:r 1156:= 1153:N 1149:, 1143:v 1138:r 1129:H 1120:u 1115:r 1107:= 1104:M 1100:, 1094:u 1089:r 1080:H 1071:u 1066:r 1058:= 1055:L 1041:H 1016:. 1011:n 1002:v 999:v 994:r 989:= 986:N 982:, 977:n 968:v 965:u 960:r 955:= 952:M 948:, 943:n 934:u 931:u 926:r 921:= 918:L 900:S 894:r 882:N 878:M 874:L 856:. 850:] 844:N 839:M 832:M 827:L 821:[ 806:} 803:v 799:r 794:u 790:r 788:{ 771:, 765:2 761:v 757:d 753:N 750:+ 747:v 744:d 740:u 737:d 733:M 730:2 727:+ 722:2 718:u 714:d 710:L 707:= 703:I 699:I 672:. 664:| 658:v 653:r 643:u 638:r 632:| 624:v 619:r 609:u 604:r 596:= 592:n 577:n 570:v 566:r 561:u 557:r 548:S 542:r 537:) 535:v 533:, 531:u 529:( 523:v 519:r 512:u 508:r 501:v 497:r 490:u 486:r 480:v 474:u 468:r 458:r 452:R 447:) 445:v 443:, 441:u 439:( 437:r 433:r 419:P 413:S 406:z 400:S 394:P 376:. 370:2 366:y 362:d 358:N 355:+ 352:y 349:d 345:x 342:d 338:M 335:2 332:+ 327:2 323:x 319:d 315:L 299:) 297:y 295:, 293:x 291:( 274:, 265:+ 260:2 255:2 251:y 245:N 242:+ 239:y 236:x 233:M 230:+ 225:2 220:2 216:x 210:L 207:= 204:z 191:f 182:y 176:x 166:f 155:z 150:) 148:y 146:, 144:x 142:( 140:f 136:z 122:R 116:S 60:I 56:I

Index

differential geometry
quadratic form
tangent plane
smooth surface
Euclidean space
first fundamental form
principal curvatures
submanifold
Riemannian manifold

parametric surface
Gauss
continuously differentiable
tangent
partial derivatives
Taylor expansion
quadratic form
vector-valued function
cross product
dot product
signed distance field
Hessian
vector-valued function
cross product
Einstein summation convention
Euclidean space
Gauss map
differential
vector-valued differential form
metric tensor

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

↑