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Simplicial complex

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of a sphere packing (a graph where vertices are the centers of spheres and edges exist if the corresponding packing elements touch each other) and as such can be used to determine the combinatorics of
241: 1934: 1441: 1112: 2124:-vector of a simplicial complex is not even necessarily positive. For instance, if we take Δ to be the 2-complex given by two triangles intersecting only at a common vertex, the resulting 1161: 1636: 442: 788: 704: 1562: 594: 1156: 1070: 1011: 959: 920: 664: 564: 728: 630: 408: 361: 337: 184: 160: 124: 295: 268: 1314:. Any finite simplicial complex in the sense talked about here can be embedded as a polytope in that sense, in some large number of dimensions. In algebraic topology, a 1678: 2869: 748: 448:. Informally, a pure 1-complex "looks" like it's made of a bunch of lines, a 2-complex "looks" like it's made of a bunch of triangles, etc. An example of a 2154:, such as the number of touching pairs (1-simplices), touching triplets (2-simplices), and touching quadruples (3-simplices) in a sphere packing. 2169: 2163: 2325: 2249: 1945: 2340: 2264: 452:-homogeneous complex is a triangle with a line segment attached to one of its vertices. Pure simplicial complexes can be thought of as 2503: 803: 2905: 2857: 2852: 2433: 2396: 2378: 2309: 475:). A pure simplicial complex can be thought of as a complex where all facets have the same dimension. For (boundary complexes of) 2847: 196: 2117: 2203: 2749: 2330: 2254: 1852: 1362: 847: 825: 2895: 2890: 2193: 2172:
is: given a finite simplicial complex, decide whether it is homeomorphic to a given geometric object. This problem is
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of a simplicial complex Δ, which is the sequence of coefficients of the polynomial that results from plugging
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which is homeomorphic to the geometric realization of a finite simplicial complex is usually called a
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directly, provided that consistent orientations are made of all simplices. The requirements of
2800: 2666: 2624: 2489: 2458: 2429: 2392: 2374: 2348: 2336: 2305: 2299: 2272: 2260: 2224: 1318: 605: 472: 47: 17: 2580: 2526: 1832:{\displaystyle F_{\Delta }(x-1)=h_{0}x^{d+1}+h_{1}x^{d}+h_{2}x^{d-1}+\cdots +h_{d}x+h_{d+1}} 190: 51: 30: 2443: 2406: 2639: 2634: 2439: 2402: 2218: 1303: 1291: 1119: 74: 1463: = 1 unless Δ is the empty complex). For instance, if Δ is the boundary of the 1282:, simplicial complexes are often useful for concrete calculations. For the definition of 486:
is used to refer to a simplex of a complex, not to be confused with a face of a simplex.
2729: 2661: 2461: 2151: 2112:-vector is symmetric. In fact, this happens whenever Δ is the boundary of a simplicial 1471:-vector is (1, 6, 12, 8), and if Δ is the first simplicial complex pictured above, its 1283: 733: 70: 2108:-vector of the boundary of the octahedron is (1, 3, 3, 1). It is not an accident this 2884: 2739: 2649: 2629: 2366: 2147: 1939:
We calculate the h-vector of the octahedron boundary (our first example) as follows:
1345: 1315: 1287: 510: 78: 2832: 2724: 2644: 2590: 2413: 2229: 514: 55: 2304:, Algorithms and Computation in Mathematics, vol. 25, Springer, p. 493, 305:, which loosely speaking is a simplicial complex without an associated geometry. 2822: 2734: 2417: 39: 2678: 2609: 2568: 2475: 1495: 1464: 1322: 1295: 368: 2146:
Simplicial complexes can be seen to have the same geometric structure as the
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Norman J. Wildberger. "Simplices and simplicial complexes". A Youtube talk.
1475:-vector is (1, 18, 23, 8, 1). A complete characterization of the possible 2688: 2656: 2605: 2512: 2113: 1299: 1037:
is generally not a simplicial complex itself, so some authors define the
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is a simplicial complex where the largest dimension of any simplex in
410:
is a simplicial complex where every simplex of dimension less than
2485: 2333:: Lectures on Topological Methods in Combinatorics and Geometry 2257:: Lectures on Topological Methods in Combinatorics and Geometry 479:
this coincides with the meaning from polyhedral combinatorics.
1310:. That somewhat more concrete concept is there attributed to 467:
is a maximal simplex, i.e., any simplex in a complex that is
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Triangulations: Structures for Algorithms and Applications
1498:(written in decreasing order of exponents), we obtain the 471:
a face of any larger simplex. (Note the difference from a
236:{\displaystyle \sigma _{1},\sigma _{2}\in {\mathcal {K}}} 1286:
of a simplicial complex, one can read the corresponding
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A complete characterization of all simplicial polytope
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in its relative interior. This simplex is called the
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is sometimes used in a broader sense to denote a set
420: 392: 345: 321: 276: 249: 199: 168: 144: 108: 2391:(Reprint of the 1980 ed.), Mineola, NY: Dover, 2335:(2nd ed.). Berlin-Heidelberg: Springer-Verlag. 2259:(2nd ed.). Berlin-Heidelberg: Springer-Verlag. 1929:{\displaystyle (h_{0},h_{1},h_{2},\cdots ,h_{d+1}).} 2748: 2712: 2598: 2519: 2221: – 1 dimensional simplicial complex 1436:{\displaystyle (f_{0},f_{1},f_{2},\ldots ,f_{d+1})} 2093: 1928: 1831: 1630: 1556: 1435: 1248: 1150: 1106: 1064: 1005: 953: 914: 782: 742: 722: 698: 658: 624: 588: 558: 436: 402: 355: 331: 289: 262: 235: 178: 154: 118: 1641:Combinatorists are often quite interested in the 1479:-vectors of simplicial complexes is given by the 1107:{\displaystyle \mathrm {Cl} \ \mathrm {st} \ S} 1013:) is the union of the stars of each simplex in 2497: 1241: 1217: 1199: 1175: 8: 1294:lead to the use of more general spaces, the 583: 573: 1456:−1)-dimensional faces of Δ (by convention, 1334: 922:) is the smallest simplicial subcomplex of 532:of its simplices. It is usually denoted by 513:to a simplex, leading to the definition of 2865: 2838: 2504: 2490: 2482: 1631:{\displaystyle x^{4}+18x^{3}+23x^{2}+8x+1} 1355:of a simplicial d-complex Δ, which is the 81:counterpart to a simplicial complex is an 2070: 2054: 2014: 1986: 1947: 1908: 1889: 1876: 1863: 1854: 1817: 1801: 1776: 1766: 1753: 1743: 1724: 1714: 1686: 1680: 1607: 1591: 1575: 1569: 1533: 1517: 1511: 1418: 1399: 1386: 1373: 1364: 1240: 1239: 1222: 1216: 1215: 1207: 1198: 1197: 1180: 1174: 1173: 1165: 1163: 1134: 1132: 1090: 1079: 1077: 1048: 1046: 989: 987: 937: 935: 898: 896: 763: 735: 714: 713: 711: 691: 685: 684: 679: 671: 651: 645: 644: 639: 637: 632:form a partition of its underlying space 616: 615: 613: 577: 576: 571: 551: 545: 544: 539: 537: 437:{\displaystyle \sigma \in {\mathcal {K}}} 428: 427: 419: 394: 393: 391: 347: 346: 344: 323: 322: 320: 281: 275: 254: 248: 227: 226: 217: 204: 198: 170: 169: 167: 146: 145: 143: 130:that satisfies the following conditions: 110: 109: 107: 1653:-polynomial of Δ. Formally, if we write 1302:of simplicial complexes as subspaces of 783:{\displaystyle \operatorname {supp} (x)} 501:-faces are sometimes referred to as its 29: 2241: 1330: 1326: 1306:made up of subsets, each of which is a 1204: 799: 2170:simplicial complex recognition problem 2164:Simplicial complex recognition problem 1502:of Δ. In our two examples above, the 699:{\displaystyle x\in |{\mathcal {K}}|} 7: 2135:-vectors is given by the celebrated 961:is obtained by repeatedly adding to 1687: 1557:{\displaystyle x^{3}+6x^{2}+12x+8} 1226: 1223: 1211: 1208: 1184: 1181: 1169: 1166: 1138: 1135: 1094: 1091: 1083: 1080: 1052: 1049: 993: 990: 941: 938: 902: 899: 706:, there is exactly one simplex in 589:{\displaystyle \|{\mathcal {K}}\|} 25: 371:or higher-dimensional simplices. 2864: 2837: 2827: 2817: 2806: 2796: 2795: 2589: 1494:-complex Δ as coefficients of a 1260:minus the stars of all faces of 1151:{\displaystyle \mathrm {Lk} \ S} 1065:{\displaystyle \mathrm {St} \ S} 1006:{\displaystyle \mathrm {st} \ S} 954:{\displaystyle \mathrm {Cl} \ S} 915:{\displaystyle \mathrm {Cl} \ S} 876:be a collection of simplices in 872:be a simplicial complex and let 846: 824: 802: 659:{\displaystyle |{\mathcal {K}}|} 559:{\displaystyle |{\mathcal {K}}|} 528:of a simplicial complex, is the 73:appearing in modern simplicial 2387:Maunder, Charles R.F. (1996), 2204:Causal dynamical triangulation 2038: 2026: 2011: 1998: 1983: 1970: 1964: 1952: 1920: 1856: 1704: 1692: 1430: 1366: 1236: 1230: 1194: 1188: 1114:the closure of the star of S. 965:each face of every simplex in 926:that contains each simplex in 777: 771: 723:{\displaystyle {\mathcal {K}}} 692: 680: 652: 640: 625:{\displaystyle {\mathcal {K}}} 552: 540: 403:{\displaystyle {\mathcal {K}}} 356:{\displaystyle {\mathcal {K}}} 332:{\displaystyle {\mathcal {K}}} 301:See also the definition of an 179:{\displaystyle {\mathcal {K}}} 155:{\displaystyle {\mathcal {K}}} 119:{\displaystyle {\mathcal {K}}} 1: 2331:Using the Borsuk-Ulam Theorem 2255:Using the Borsuk-Ulam Theorem 18:Facet of a simplicial complex 2347:Written in cooperation with 2271:Written in cooperation with 2120:). In general, however, the 456:and provide a definition of 87:geometric simplicial complex 2194:Abstract simplicial complex 2180:-dimensional manifolds for 1668:-polynomial of Δ, then the 1256:. It is the closed star of 1025:is the set of simplices in 303:abstract simplicial complex 290:{\displaystyle \sigma _{2}} 263:{\displaystyle \sigma _{1}} 83:abstract simplicial complex 2922: 2758:Banach fixed-point theorem 2426:Cambridge University Press 2161: 2118:Dehn–Sommerville equations 1271: 414:is a face of some simplex 2791: 2587: 489:For a simplicial complex 67:-dimensional counterparts 2906:Triangulation (geometry) 1649: − 1 into the 1490:-vector of a simplicial 497:-dimensional space, the 2199:Barycentric subdivision 2128:-vector is (1, 3, −2). 1335:Hilton & Wylie 1967 1033:as a face. The star of 1017:. For a single simplex 796:Closure, star, and link 524:, sometimes called the 34:A simplicial 3-complex. 2813:Mathematics portal 2713:Metrics and properties 2699:Second-countable space 2158:Computational problems 2095: 1930: 1833: 1632: 1558: 1506:-polynomials would be 1481:Kruskal–Katona theorem 1437: 1250: 1152: 1108: 1066: 1007: 955: 916: 784: 744: 724: 700: 660: 626: 590: 560: 438: 404: 357: 333: 291: 264: 237: 180: 156: 120: 35: 2096: 1931: 1834: 1633: 1559: 1438: 1251: 1153: 1109: 1067: 1008: 956: 917: 785: 745: 725: 701: 661: 627: 591: 561: 444:of dimension exactly 439: 405: 358: 334: 292: 265: 238: 193:of any two simplices 181: 157: 121: 33: 2768:Invariance of domain 2720:Euler characteristic 2694:Bundle (mathematics) 2462:"Simplicial complex" 2214:Loop quantum gravity 2143:, Billera, and Lee. 1946: 1853: 1679: 1568: 1510: 1363: 1162: 1131: 1076: 1045: 986: 934: 895: 762: 734: 710: 670: 636: 612: 608:of all simplices in 570: 536: 477:simplicial polytopes 418: 390: 343: 319: 274: 247: 197: 166: 142: 106: 2778:Tychonoff's theorem 2773:Poincaré conjecture 2527:General (point-set) 1274:Simplicial homology 482:Sometimes the term 473:"face" of a simplex 2896:Algebraic topology 2891:Topological spaces 2763:De Rham cohomology 2684:Polyhedral complex 2674:Simplicial complex 2459:Weisstein, Eric W. 2389:Algebraic Topology 2371:Algebraic Topology 2292:De Loera, Jesús A. 2091: 1926: 1829: 1628: 1554: 1452:is the number of ( 1433: 1280:algebraic topology 1268:Algebraic topology 1246: 1148: 1104: 1062: 1003: 951: 912: 780: 740: 720: 696: 656: 622: 606:relative interiors 586: 556: 434: 400: 353: 329: 287: 260: 243:is a face of both 233: 176: 152: 138:of a simplex from 116: 101:simplicial complex 44:simplicial complex 36: 2878: 2877: 2667:fundamental group 2367:Spanier, Edwin H. 2353:Günter M. Ziegler 2342:978-3-540-00362-5 2296:Santos, Francisco 2277:Günter M. Ziegler 2266:978-3-540-00362-5 1346:Combinatorialists 1319:topological space 1144: 1100: 1089: 1058: 999: 947: 908: 743:{\displaystyle x} 666:: for each point 189:2. The non-empty 16:(Redirected from 2913: 2868: 2867: 2841: 2840: 2831: 2821: 2811: 2810: 2799: 2798: 2593: 2506: 2499: 2492: 2483: 2472: 2471: 2446: 2414:Hilton, Peter J. 2409: 2383: 2358: 2356: 2322: 2316: 2314: 2294:; Rambau, Jörg; 2288: 2282: 2280: 2246: 2100: 2098: 2097: 2092: 2075: 2074: 2059: 2058: 2019: 2018: 1991: 1990: 1935: 1933: 1932: 1927: 1919: 1918: 1894: 1893: 1881: 1880: 1868: 1867: 1846:-vector of Δ is 1838: 1836: 1835: 1830: 1828: 1827: 1806: 1805: 1787: 1786: 1771: 1770: 1758: 1757: 1748: 1747: 1735: 1734: 1719: 1718: 1691: 1690: 1638:, respectively. 1637: 1635: 1634: 1629: 1612: 1611: 1596: 1595: 1580: 1579: 1563: 1561: 1560: 1555: 1538: 1537: 1522: 1521: 1442: 1440: 1439: 1434: 1429: 1428: 1404: 1403: 1391: 1390: 1378: 1377: 1348:often study the 1255: 1253: 1252: 1247: 1245: 1244: 1229: 1221: 1220: 1214: 1203: 1202: 1187: 1179: 1178: 1172: 1157: 1155: 1154: 1149: 1142: 1141: 1113: 1111: 1110: 1105: 1098: 1097: 1087: 1086: 1071: 1069: 1068: 1063: 1056: 1055: 1012: 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1082: 1061: 1054: 1051: 1041:of S (denoted 1021:, the star of 1002: 995: 992: 950: 943: 940: 911: 904: 901: 866: 865: 852: 845: 843: 830: 823: 821: 808: 801: 797: 794: 779: 776: 773: 770: 767: 739: 717: 694: 688: 682: 678: 675: 654: 648: 642: 619: 601: 598: 585: 580: 575: 554: 548: 542: 454:triangulations 431: 426: 423: 397: 350: 326: 299: 298: 284: 280: 257: 253: 230: 225: 220: 216: 212: 207: 203: 187: 173: 149: 113: 96: 93: 71:simplicial set 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 2918: 2907: 2904: 2902: 2899: 2897: 2894: 2892: 2889: 2888: 2886: 2871: 2863: 2859: 2856: 2854: 2851: 2849: 2846: 2845: 2844: 2836: 2834: 2830: 2826: 2824: 2820: 2816: 2814: 2809: 2804: 2802: 2794: 2793: 2790: 2784: 2781: 2779: 2776: 2774: 2771: 2769: 2766: 2764: 2761: 2759: 2756: 2755: 2753: 2751: 2747: 2741: 2740:Orientability 2738: 2736: 2733: 2731: 2728: 2726: 2723: 2721: 2718: 2717: 2715: 2711: 2705: 2702: 2700: 2697: 2695: 2692: 2690: 2687: 2685: 2682: 2680: 2677: 2675: 2672: 2668: 2665: 2663: 2660: 2659: 2658: 2655: 2651: 2648: 2646: 2643: 2641: 2638: 2636: 2633: 2631: 2628: 2627: 2626: 2623: 2621: 2618: 2616: 2613: 2611: 2607: 2604: 2603: 2601: 2597: 2592: 2582: 2579: 2577: 2576:Set-theoretic 2574: 2570: 2567: 2566: 2565: 2562: 2558: 2555: 2554: 2553: 2550: 2548: 2545: 2543: 2540: 2538: 2537:Combinatorial 2535: 2533: 2530: 2528: 2525: 2524: 2522: 2518: 2514: 2507: 2502: 2500: 2495: 2493: 2488: 2487: 2484: 2477: 2474: 2469: 2468: 2463: 2460: 2455: 2454: 2450: 2445: 2441: 2437: 2435:0-521-09422-4 2431: 2427: 2423: 2419: 2415: 2411: 2408: 2404: 2400: 2398:0-486-69131-4 2394: 2390: 2385: 2382: 2380:0-387-94426-5 2376: 2372: 2368: 2364: 2363: 2357:, Section 4.3 2355: 2354: 2350: 2344: 2338: 2334: 2332: 2327: 2321: 2318: 2313: 2311:9783642129711 2307: 2303: 2302: 2297: 2293: 2287: 2284: 2281:, Section 4.3 2279: 2278: 2274: 2268: 2262: 2258: 2256: 2251: 2245: 2242: 2235: 2231: 2228: 2226: 2223: 2220: 2217: 2215: 2212: 2210: 2207: 2205: 2202: 2200: 2197: 2195: 2192: 2191: 2187: 2185: 2183: 2179: 2175: 2171: 2165: 2157: 2155: 2153: 2149: 2148:contact graph 2144: 2142: 2138: 2134: 2129: 2127: 2123: 2119: 2115: 2111: 2107: 2088: 2085: 2082: 2079: 2076: 2071: 2067: 2063: 2060: 2055: 2051: 2047: 2044: 2041: 2035: 2032: 2029: 2023: 2020: 2015: 2007: 2004: 2001: 1995: 1992: 1987: 1979: 1976: 1973: 1967: 1961: 1958: 1955: 1949: 1942: 1941: 1940: 1923: 1915: 1912: 1909: 1905: 1901: 1898: 1895: 1890: 1886: 1882: 1877: 1873: 1869: 1864: 1860: 1849: 1848: 1847: 1845: 1824: 1821: 1818: 1814: 1810: 1807: 1802: 1798: 1794: 1791: 1788: 1783: 1780: 1777: 1773: 1767: 1763: 1759: 1754: 1750: 1744: 1740: 1736: 1731: 1728: 1725: 1721: 1715: 1711: 1707: 1701: 1698: 1695: 1683: 1675: 1674: 1673: 1671: 1667: 1663: 1656: 1652: 1648: 1644: 1639: 1625: 1622: 1619: 1616: 1613: 1608: 1604: 1600: 1597: 1592: 1588: 1584: 1581: 1576: 1572: 1551: 1548: 1545: 1542: 1539: 1534: 1530: 1526: 1523: 1518: 1514: 1505: 1501: 1497: 1493: 1489: 1486:By using the 1484: 1482: 1478: 1474: 1470: 1466: 1459: 1455: 1450: 1446: 1425: 1422: 1419: 1415: 1411: 1408: 1405: 1400: 1396: 1392: 1387: 1383: 1379: 1374: 1370: 1358: 1354: 1352: 1347: 1341:Combinatorics 1340: 1338: 1336: 1332: 1328: 1324: 1320: 1317: 1313: 1309: 1305: 1301: 1297: 1293: 1289: 1288:chain complex 1285: 1281: 1275: 1267: 1265: 1263: 1259: 1233: 1191: 1145: 1126: 1122: 1121: 1115: 1101: 1059: 1040: 1036: 1032: 1028: 1024: 1020: 1016: 1000: 981: 977: 976: 970: 968: 964: 948: 929: 925: 909: 890: 886: 881: 879: 875: 871: 861: 849: 844: 839: 827: 822: 817: 805: 800: 795: 793: 792: 774: 768: 765: 757: 753: 737: 676: 673: 607: 599: 597: 531: 527: 523: 518: 516: 512: 508: 504: 500: 496: 492: 487: 485: 480: 478: 474: 470: 466: 461: 459: 455: 451: 447: 424: 421: 413: 385: 381: 377: 372: 370: 366: 315: 313: 306: 304: 282: 278: 255: 251: 223: 218: 214: 210: 205: 201: 192: 188: 137: 133: 132: 131: 129: 102: 94: 92: 91: 88: 84: 80: 79:combinatorial 77:. The purely 76: 72: 68: 66: 61: 57: 56:line segments 53: 49: 45: 41: 32: 19: 2870:Publications 2735:Chern number 2725:Betti number 2673: 2608: / 2599:Key concepts 2547:Differential 2465: 2424:, New York: 2421: 2418:Wylie, Shaun 2388: 2373:, Springer, 2370: 2346: 2329: 2320: 2300: 2286: 2270: 2253: 2244: 2230:Simplex tree 2181: 2177: 2167: 2145: 2132: 2130: 2125: 2121: 2109: 2105: 2103: 1938: 1843: 1841: 1670:h-polynomial 1669: 1665: 1661: 1654: 1650: 1646: 1642: 1640: 1503: 1500:f-polynomial 1499: 1491: 1487: 1485: 1476: 1472: 1468: 1457: 1453: 1448: 1444: 1350: 1349: 1344: 1331:Maunder 1996 1327:Spanier 1966 1296:CW complexes 1277: 1261: 1257: 1124: 1118: 1116: 1038: 1034: 1030: 1026: 1022: 1018: 1014: 979: 973: 971: 966: 962: 927: 923: 888: 884: 882: 877: 873: 869: 867: 859: 837: 815: 791: 758:and denoted 755: 751: 603: 525: 521: 519: 515:cell complex 511:homeomorphic 506: 502: 498: 494: 488: 483: 481: 468: 464: 462: 449: 445: 411: 383: 379: 375: 373: 364: 311: 309: 307: 300: 191:intersection 126:is a set of 100: 98: 90: 86: 64: 62:, and their 50:composed of 43: 37: 2833:Wikiversity 2750:Key results 2174:undecidable 1467:, then its 1039:closed star 730:containing 505:. The term 382:simplicial 380:homogeneous 310:simplicial 162:is also in 95:Definitions 40:mathematics 2885:Categories 2679:CW complex 2620:Continuity 2610:Closed set 2569:cohomology 2236:References 1496:polynomial 1465:octahedron 1323:polyhedron 1312:Alexandrov 1029:that have 813:and their 369:tetrahedra 2858:geometric 2853:algebraic 2704:Cobordism 2640:Hausdorff 2635:connected 2552:Geometric 2542:Continuum 2532:Algebraic 2467:MathWorld 2209:Delta set 2137:g-theorem 2033:− 2005:− 1977:− 1959:− 1899:⋯ 1792:⋯ 1781:− 1699:− 1688:Δ 1409:… 1359:sequence 1205:∖ 1158:) equals 1127:(denoted 982:(denoted 891:(denoted 811:simplices 769:⁡ 677:∈ 584:‖ 574:‖ 458:polytopes 425:∈ 422:σ 386:-complex 279:σ 252:σ 224:∈ 215:σ 202:σ 134:1. Every 128:simplices 60:triangles 2823:Wikibook 2801:Category 2689:Manifold 2657:Homotopy 2615:Interior 2606:Open set 2564:Homology 2513:Topology 2420:(1967), 2369:(1966), 2328:(2007). 2298:(2010), 2252:(2007). 2188:See also 2176:for any 2114:polytope 1842:and the 1672:of Δ is 1643:h-vector 1443:, where 1300:Polytope 857:and its 835:and its 491:embedded 314:-complex 2848:general 2650:uniform 2630:compact 2581:Digital 2444:0115161 2407:1402473 2141:Stanley 2104:So the 1357:integer 1353:-vector 1316:compact 1308:simplex 885:closure 816:closure 752:support 600:Support 526:carrier 363:equals 2843:Topics 2645:metric 2520:Fields 2442:  2432:  2405:  2395:  2377:  2339:  2308:  2263:  1143:  1099:  1088:  1057:  998:  946:  907:  855:vertex 833:vertex 52:points 2625:Space 2184:≥ 5. 1325:(see 1072:) as 530:union 503:cells 493:in a 465:facet 46:is a 2430:ISBN 2393:ISBN 2375:ISBN 2351:and 2337:ISBN 2306:ISBN 2275:and 2261:ISBN 2168:The 1564:and 1120:link 1117:The 975:star 972:The 883:The 868:Let 860:link 838:star 809:Two 766:supp 604:The 520:The 507:cell 484:face 376:pure 270:and 136:face 42:, a 2139:of 1337:). 1278:In 1123:of 978:of 887:of 754:of 566:or 469:not 450:non 378:or 48:set 38:In 2887:: 2464:. 2440:MR 2438:, 2428:, 2416:; 2403:MR 2401:, 2345:. 2269:. 2089:1. 2024:12 1601:23 1585:18 1543:12 1483:. 1333:, 1329:, 1264:. 969:. 930:. 880:. 853:A 831:A 596:. 517:. 463:A 460:. 374:A 308:A 99:A 58:, 54:, 2505:e 2498:t 2491:v 2478:. 2470:. 2315:. 2182:d 2178:d 2133:h 2126:h 2122:h 2110:h 2106:h 2086:+ 2083:x 2080:3 2077:+ 2072:2 2068:x 2064:3 2061:+ 2056:3 2052:x 2048:= 2045:8 2042:+ 2039:) 2036:1 2030:x 2027:( 2021:+ 2016:2 2012:) 2008:1 2002:x 1999:( 1996:6 1993:+ 1988:3 1984:) 1980:1 1974:x 1971:( 1968:= 1965:) 1962:1 1956:x 1953:( 1950:F 1924:. 1921:) 1916:1 1913:+ 1910:d 1906:h 1902:, 1896:, 1891:2 1887:h 1883:, 1878:1 1874:h 1870:, 1865:0 1861:h 1857:( 1844:h 1825:1 1822:+ 1819:d 1815:h 1811:+ 1808:x 1803:d 1799:h 1795:+ 1789:+ 1784:1 1778:d 1774:x 1768:2 1764:h 1760:+ 1755:d 1751:x 1745:1 1741:h 1737:+ 1732:1 1729:+ 1726:d 1722:x 1716:0 1712:h 1708:= 1705:) 1702:1 1696:x 1693:( 1684:F 1666:f 1662:x 1660:( 1658:Δ 1655:F 1651:f 1647:x 1626:1 1623:+ 1620:x 1617:8 1614:+ 1609:2 1605:x 1598:+ 1593:3 1589:x 1582:+ 1577:4 1573:x 1552:8 1549:+ 1546:x 1540:+ 1535:2 1531:x 1527:6 1524:+ 1519:3 1515:x 1504:f 1492:d 1488:f 1477:f 1473:f 1469:f 1461:0 1458:f 1454:i 1449:i 1445:f 1431:) 1426:1 1423:+ 1420:d 1416:f 1412:, 1406:, 1401:2 1397:f 1393:, 1388:1 1384:f 1380:, 1375:0 1371:f 1367:( 1351:f 1262:S 1258:S 1242:) 1237:) 1234:S 1231:( 1227:l 1224:C 1218:( 1212:t 1209:s 1200:) 1195:) 1192:S 1189:( 1185:t 1182:s 1176:( 1170:l 1167:C 1146:S 1139:k 1136:L 1125:S 1102:S 1095:t 1092:s 1084:l 1081:C 1060:S 1053:t 1050:S 1035:S 1031:s 1027:K 1023:s 1019:s 1015:S 1001:S 994:t 991:s 980:S 967:S 963:S 949:S 942:l 939:C 928:S 924:K 910:S 903:l 900:C 889:S 878:K 874:S 870:K 863:. 841:. 819:. 790:. 778:) 775:x 772:( 756:x 738:x 716:K 693:| 687:K 681:| 674:x 653:| 647:K 641:| 618:K 579:K 553:| 547:K 541:| 499:k 495:k 446:k 430:K 412:k 396:K 384:k 365:k 349:K 325:K 312:k 297:. 283:2 256:1 229:K 219:2 211:, 206:1 186:. 172:K 148:K 112:K 89:. 65:n 20:)

Index

Facet of a simplicial complex

mathematics
set
points
line segments
triangles
n-dimensional counterparts
simplicial set
homotopy theory
combinatorial
abstract simplicial complex
simplices
face
intersection
abstract simplicial complex
tetrahedra
triangulations
polytopes
"face" of a simplex
simplicial polytopes
embedded
homeomorphic
cell complex
union
relative interiors
Two simplices and their closure.
A vertex and its star.
A vertex and its link.
star

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