Knowledge (XXG)

Cup product

Source 📝

2213: 2635: 372: 900: 1572: 1101: 1326: 195: 1866: 1789: 1445: 766: 2056: 1453: 1963: 1675:
This composition passes to the quotient to give a well-defined map in terms of cohomology, this is the cup product. This approach explains the existence of a cup product for cohomology but not for homology:
2617: 905:
The cup product of two cocycles is again a cocycle, and the product of a coboundary with a cocycle (in either order) is a coboundary. The cup product operation induces a bilinear operation on cohomology,
996: 689: 466: 1227: 612: 2122: 1712: 1670: 2502: 2247: 1150: 552: 731: 152: 758: 183: 1625: 2394: 2161: 502: 2420: 2324: 2422:. By taking the images of the fundamental homology classes of these manifolds under inclusion, one can obtain a bilinear product on homology. This product is 2364: 2344: 2298: 2274: 1599: 2626:
can be defined in terms of intersections, shifting dimensions by 1, or alternatively in terms of a non-vanishing cup product on the complement of a link.
1012: 367:{\displaystyle (\alpha ^{p}\smile \beta ^{q})(\sigma )=\alpha ^{p}(\sigma \circ \iota _{0,1,...p})\cdot \beta ^{q}(\sigma \circ \iota _{p,p+1,...,p+q})} 1242: 1794: 1717: 895:{\displaystyle \delta (\alpha ^{p}\smile \beta ^{q})=\delta {\alpha ^{p}}\smile \beta ^{q}+(-1)^{p}(\alpha ^{p}\smile \delta {\beta ^{q}}).} 1567:{\displaystyle \displaystyle C^{\bullet }(X)\times C^{\bullet }(X)\to C^{\bullet }(X\times X){\overset {\Delta ^{*}}{\to }}C^{\bullet }(X)} 1358: 51:. This defines an associative (and distributive) graded commutative product operation in cohomology, turning the cohomology of a space 2201: 1968: 1878: 2509: 2799: 2785: 2771: 2763: 2220:
can be defined in terms of a non-vanishing cup product on the complement of a link. The complement of these two linked circles in
2167:
multiplication in the first cohomology group can be used to decompose the torus as a 2-cell diagram, thus having product equal to
912: 625: 396: 2367: 124: 2819: 2655:
The cup product is a binary (2-ary) operation; one can define a ternary (3-ary) and higher order operation called the
1161: 2065:
Cup products may be used to distinguish manifolds from wedges of spaces with identical cohomology groups. The space
560: 2824: 68: 2068: 1679: 1637: 2814: 2249:
deformation retracts to a wedge sum of a torus and 2-sphere, which has a non-vanishing cup product in degree 1.
2429: 2253:
For oriented manifolds, there is a geometric heuristic that "the cup product is dual to intersections."
1868:, which goes the wrong way round to allow us to define a product. This is however of use in defining the 2204:
differential forms belongs to the de Rham class of the cup product of the two original de Rham classes.
2758:
James R. Munkres, "Elements of Algebraic Topology", Perseus Publishing, Cambridge Massachusetts (1984)
2223: 2660: 1123: 2423: 507: 92: 2740: 2193: 2189: 709: 130: 24: 1628: 736: 161: 1604: 2795: 2781: 2767: 2759: 2716: 2672: 2642: 1344: 378: 114: 2373: 1632: 1107: 80: 2139: 475: 2677: 2277: 103: 76: 64: 2399: 2303: 2777: 2687: 2656: 2650: 2638: 2623: 2349: 2329: 2283: 2259: 2217: 1584: 72: 2791: 2808: 2692: 2197: 1578: 1096:{\displaystyle \alpha ^{p}\smile \beta ^{q}=(-1)^{pq}(\beta ^{q}\smile \alpha ^{p})} 2641:
generalize cup product, allowing one to define "higher order linking numbers", the
1233: 2682: 1869: 100: 20: 2212: 1321:{\displaystyle f^{*}(\alpha \smile \beta )=f^{*}(\alpha )\smile f^{*}(\beta ),} 2734: 703: 2634: 1861:{\displaystyle \Delta _{*}\colon H_{\bullet }(X)\to H_{\bullet }(X\times X)} 1784:{\displaystyle \Delta ^{*}\colon H^{\bullet }(X\times X)\to H^{\bullet }(X)} 469: 2133: 1114: 390: 32: 2426:
to the cup product, in the sense that taking the Poincaré pairings
1440:{\displaystyle \smile \colon H^{p}(X)\times H^{q}(X)\to H^{p+q}(X)} 2633: 2211: 2051:{\displaystyle u\smile (v_{1}+v_{2})=u\smile v_{1}+u\smile v_{2}.} 1958:{\displaystyle (u_{1}+u_{2})\smile v=u_{1}\smile v+u_{2}\smile v} 2663:, which is only partly defined (only defined for some triples). 1875:
Bilinearity follows from this presentation of cup product, i.e.
2612:{\displaystyle ^{*}\smile ^{*}=^{*}\in H^{i+j}(X,\mathbb {Z} )} 1006:
The cup product operation in cohomology satisfies the identity
2780:, "Topology and Geometry", Springer-Verlag, New York (1993) 2659:, which generalizes the cup product. This is a higher order 991:{\displaystyle H^{p}(X)\times H^{q}(X)\to H^{p+q}(X).} 2512: 2432: 2402: 2376: 2352: 2332: 2306: 2286: 2262: 2226: 2142: 2071: 1971: 1881: 1797: 1720: 1682: 1640: 1607: 1587: 1457: 1456: 1361: 1245: 1164: 1126: 1015: 915: 769: 739: 712: 628: 563: 510: 478: 399: 198: 164: 133: 2128:, but with a different cup product. In the case of 684:{\displaystyle \sigma \circ \iota _{p,p+1,...,p+q}} 461:{\displaystyle \iota _{S},S\subset \{0,1,...,p+q\}} 2611: 2496: 2414: 2388: 2358: 2338: 2318: 2292: 2268: 2241: 2155: 2116: 2050: 1957: 1860: 1783: 1706: 1664: 1619: 1593: 1566: 1439: 1320: 1221: 1144: 1095: 990: 894: 752: 725: 683: 606: 546: 496: 460: 366: 177: 146: 16:Turns the cohomology of a space into a graded ring 1222:{\displaystyle f^{*}\colon H^{*}(Y)\to H^{*}(X)} 2736:Informal talk in Derived Geometry (Jacob Lurie) 607:{\displaystyle \sigma \circ \iota _{0,1,...,p}} 2504:then there is the following equality : 67:. The cup product was introduced in work of 8: 2124:has the same cohomology groups as the torus 2117:{\displaystyle X:=S^{2}\vee S^{1}\vee S^{1}} 1707:{\displaystyle \Delta \colon X\to X\times X} 1665:{\displaystyle \Delta \colon X\to X\times X} 1106:so that the corresponding multiplication is 541: 511: 455: 419: 79:from 1935–1938, and, in full generality, by 2200:. In other words, the wedge product of two 1447:as induced from the following composition: 123:The construction starts with a product of 99:is a construction giving a product on the 2602: 2601: 2580: 2567: 2542: 2523: 2511: 2488: 2475: 2462: 2443: 2431: 2401: 2375: 2351: 2331: 2305: 2285: 2261: 2233: 2229: 2228: 2225: 2147: 2141: 2108: 2095: 2082: 2070: 2039: 2020: 1998: 1985: 1970: 1943: 1924: 1902: 1889: 1880: 1837: 1815: 1802: 1796: 1766: 1738: 1725: 1719: 1681: 1639: 1631:and the second is the map induced by the 1606: 1586: 1548: 1536: 1527: 1506: 1484: 1462: 1455: 1416: 1394: 1372: 1360: 1300: 1278: 1250: 1244: 1204: 1182: 1169: 1163: 1125: 1084: 1071: 1055: 1033: 1020: 1014: 964: 942: 920: 914: 879: 874: 862: 849: 827: 813: 808: 793: 780: 768: 744: 738: 717: 711: 639: 627: 574: 562: 509: 477: 404: 398: 319: 300: 263: 244: 219: 206: 197: 169: 163: 138: 132: 2497:{\displaystyle ^{*},^{*}\in H^{i},H^{j}} 2794:", Cambridge Publishing Company (2002) 2704: 2208:Cup product and geometric intersections 1355:It is possible to view the cup product 504:-simplex whose vertices are indexed by 2396:is again a submanifold of codimension 43:to form a composite cocycle of degree 472:of the simplex spanned by S into the 7: 2710: 2708: 2184:Cup product and differential forms 1799: 1722: 1683: 1641: 1533: 14: 2242:{\displaystyle \mathbb {R} ^{3}} 2175:where this is the base module). 2743:from the original on 2021-12-21 2717:"Cup Product and Intersections" 1155:is a continuous function, and 1117:, in the following sense: if 706:of the cup product of cochains 2606: 2592: 2564: 2551: 2539: 2532: 2520: 2513: 2459: 2452: 2440: 2433: 2004: 1978: 1908: 1882: 1855: 1843: 1830: 1827: 1821: 1778: 1772: 1759: 1756: 1744: 1692: 1650: 1560: 1554: 1529: 1524: 1512: 1499: 1496: 1490: 1474: 1468: 1434: 1428: 1409: 1406: 1400: 1384: 1378: 1312: 1306: 1290: 1284: 1268: 1256: 1216: 1210: 1197: 1194: 1188: 1145:{\displaystyle f\colon X\to Y} 1136: 1090: 1064: 1052: 1042: 982: 976: 957: 954: 948: 932: 926: 886: 855: 846: 836: 799: 773: 491: 479: 361: 306: 290: 250: 234: 228: 225: 199: 1: 1627:, where the first map is the 547:{\displaystyle \{0,...,p+q\}} 31:is a method of adjoining two 2136:associated to the copies of 1791:but would also induce a map 726:{\displaystyle \alpha ^{p}} 147:{\displaystyle \alpha ^{p}} 2841: 2733:Ciencias TV (2016-12-10), 2648: 2370:, then their intersection 2163:is degenerate, whereas in 2132:the multiplication of the 753:{\displaystyle \beta ^{q}} 178:{\displaystyle \beta ^{q}} 1620:{\displaystyle X\times X} 1331:for all classes α, β in 2389:{\displaystyle A\cap B} 2646: 2613: 2498: 2416: 2390: 2360: 2340: 2320: 2300:. If two submanifolds 2294: 2270: 2250: 2243: 2157: 2118: 2052: 1959: 1862: 1785: 1708: 1666: 1621: 1595: 1575: 1568: 1441: 1322: 1223: 1146: 1097: 992: 896: 754: 727: 685: 608: 548: 498: 462: 368: 179: 148: 2637: 2614: 2499: 2417: 2391: 2361: 2341: 2321: 2295: 2271: 2244: 2215: 2192:, the cup product of 2158: 2156:{\displaystyle S^{1}} 2119: 2053: 1960: 1863: 1786: 1709: 1667: 1622: 1596: 1569: 1449: 1442: 1323: 1236:in cohomology, then 1224: 1147: 1098: 993: 897: 755: 728: 686: 609: 549: 499: 497:{\displaystyle (p+q)} 463: 369: 180: 149: 2715:Hutchings, Michael. 2661:cohomology operation 2510: 2430: 2400: 2374: 2350: 2330: 2304: 2284: 2260: 2224: 2140: 2069: 1969: 1879: 1795: 1718: 1680: 1638: 1605: 1585: 1454: 1359: 1243: 1162: 1124: 1013: 913: 767: 737: 710: 699:of σ, respectively. 626: 561: 508: 476: 397: 196: 162: 131: 55:into a graded ring, 2415:{\displaystyle i+j} 2319:{\displaystyle A,B} 1339:). In other words, 1113:The cup product is 93:singular cohomology 2820:Algebraic topology 2792:Algebraic Topology 2647: 2609: 2494: 2412: 2386: 2356: 2336: 2316: 2290: 2266: 2251: 2239: 2196:is induced by the 2194:differential forms 2190:de Rham cohomology 2153: 2114: 2048: 1955: 1858: 1781: 1704: 1662: 1617: 1591: 1564: 1563: 1437: 1318: 1219: 1142: 1108:graded-commutative 1093: 988: 892: 750: 723: 681: 604: 544: 494: 458: 364: 175: 144: 25:algebraic topology 23:, specifically in 2825:Binary operations 2673:Singular homology 2643:Milnor invariants 2359:{\displaystyle j} 2339:{\displaystyle i} 2293:{\displaystyle n} 2269:{\displaystyle M} 2179:Other definitions 1594:{\displaystyle X} 1542: 1345:ring homomorphism 468:is the canonical 115:topological space 2832: 2790:Allen Hatcher, " 2751: 2750: 2749: 2748: 2730: 2724: 2723: 2721: 2712: 2618: 2616: 2615: 2610: 2605: 2591: 2590: 2572: 2571: 2547: 2546: 2528: 2527: 2503: 2501: 2500: 2495: 2493: 2492: 2480: 2479: 2467: 2466: 2448: 2447: 2421: 2419: 2418: 2413: 2395: 2393: 2392: 2387: 2365: 2363: 2362: 2357: 2345: 2343: 2342: 2337: 2325: 2323: 2322: 2317: 2299: 2297: 2296: 2291: 2276:be an oriented 2275: 2273: 2272: 2267: 2248: 2246: 2245: 2240: 2238: 2237: 2232: 2171:(more generally 2162: 2160: 2159: 2154: 2152: 2151: 2123: 2121: 2120: 2115: 2113: 2112: 2100: 2099: 2087: 2086: 2057: 2055: 2054: 2049: 2044: 2043: 2025: 2024: 2003: 2002: 1990: 1989: 1964: 1962: 1961: 1956: 1948: 1947: 1929: 1928: 1907: 1906: 1894: 1893: 1867: 1865: 1864: 1859: 1842: 1841: 1820: 1819: 1807: 1806: 1790: 1788: 1787: 1782: 1771: 1770: 1743: 1742: 1730: 1729: 1713: 1711: 1710: 1705: 1671: 1669: 1668: 1663: 1626: 1624: 1623: 1618: 1600: 1598: 1597: 1592: 1577:in terms of the 1573: 1571: 1570: 1565: 1553: 1552: 1543: 1541: 1540: 1528: 1511: 1510: 1489: 1488: 1467: 1466: 1446: 1444: 1443: 1438: 1427: 1426: 1399: 1398: 1377: 1376: 1327: 1325: 1324: 1319: 1305: 1304: 1283: 1282: 1255: 1254: 1228: 1226: 1225: 1220: 1209: 1208: 1187: 1186: 1174: 1173: 1151: 1149: 1148: 1143: 1102: 1100: 1099: 1094: 1089: 1088: 1076: 1075: 1063: 1062: 1038: 1037: 1025: 1024: 997: 995: 994: 989: 975: 974: 947: 946: 925: 924: 901: 899: 898: 893: 885: 884: 883: 867: 866: 854: 853: 832: 831: 819: 818: 817: 798: 797: 785: 784: 759: 757: 756: 751: 749: 748: 732: 730: 729: 724: 722: 721: 690: 688: 687: 682: 680: 679: 613: 611: 610: 605: 603: 602: 553: 551: 550: 545: 503: 501: 500: 495: 467: 465: 464: 459: 409: 408: 373: 371: 370: 365: 360: 359: 305: 304: 289: 288: 249: 248: 224: 223: 211: 210: 189:-cochain, then 184: 182: 181: 176: 174: 173: 153: 151: 150: 145: 143: 142: 81:Samuel Eilenberg 2840: 2839: 2835: 2834: 2833: 2831: 2830: 2829: 2815:Homology theory 2805: 2804: 2755: 2754: 2746: 2744: 2732: 2731: 2727: 2719: 2714: 2713: 2706: 2701: 2678:Homology theory 2669: 2653: 2639:Massey products 2632: 2630:Massey products 2622:Similarly, the 2576: 2563: 2538: 2519: 2508: 2507: 2484: 2471: 2458: 2439: 2428: 2427: 2398: 2397: 2372: 2371: 2348: 2347: 2328: 2327: 2326:of codimension 2302: 2301: 2282: 2281: 2278:smooth manifold 2258: 2257: 2227: 2222: 2221: 2210: 2186: 2181: 2143: 2138: 2137: 2104: 2091: 2078: 2067: 2066: 2063: 2035: 2016: 1994: 1981: 1967: 1966: 1939: 1920: 1898: 1885: 1877: 1876: 1833: 1811: 1798: 1793: 1792: 1762: 1734: 1721: 1716: 1715: 1678: 1677: 1636: 1635: 1603: 1602: 1583: 1582: 1579:chain complexes 1544: 1532: 1502: 1480: 1458: 1452: 1451: 1412: 1390: 1368: 1357: 1356: 1353: 1296: 1274: 1246: 1241: 1240: 1232:is the induced 1200: 1178: 1165: 1160: 1159: 1122: 1121: 1080: 1067: 1051: 1029: 1016: 1011: 1010: 1004: 960: 938: 916: 911: 910: 875: 858: 845: 823: 809: 789: 776: 765: 764: 740: 735: 734: 713: 708: 707: 635: 624: 623: 570: 559: 558: 506: 505: 474: 473: 400: 395: 394: 315: 296: 259: 240: 215: 202: 194: 193: 165: 160: 159: 134: 129: 128: 104:cohomology ring 89: 77:Hassler Whitney 69:J. W. Alexander 65:cohomology ring 17: 12: 11: 5: 2838: 2836: 2828: 2827: 2822: 2817: 2807: 2806: 2803: 2802: 2788: 2778:Glen E. Bredon 2775: 2753: 2752: 2725: 2703: 2702: 2700: 2697: 2696: 2695: 2690: 2688:Massey product 2685: 2680: 2675: 2668: 2665: 2657:Massey product 2651:Massey product 2649:Main article: 2631: 2628: 2624:linking number 2608: 2604: 2600: 2597: 2594: 2589: 2586: 2583: 2579: 2575: 2570: 2566: 2562: 2559: 2556: 2553: 2550: 2545: 2541: 2537: 2534: 2531: 2526: 2522: 2518: 2515: 2491: 2487: 2483: 2478: 2474: 2470: 2465: 2461: 2457: 2454: 2451: 2446: 2442: 2438: 2435: 2411: 2408: 2405: 2385: 2382: 2379: 2355: 2335: 2315: 2312: 2309: 2289: 2265: 2236: 2231: 2218:linking number 2209: 2206: 2185: 2182: 2180: 2177: 2150: 2146: 2111: 2107: 2103: 2098: 2094: 2090: 2085: 2081: 2077: 2074: 2062: 2059: 2047: 2042: 2038: 2034: 2031: 2028: 2023: 2019: 2015: 2012: 2009: 2006: 2001: 1997: 1993: 1988: 1984: 1980: 1977: 1974: 1954: 1951: 1946: 1942: 1938: 1935: 1932: 1927: 1923: 1919: 1916: 1913: 1910: 1905: 1901: 1897: 1892: 1888: 1884: 1857: 1854: 1851: 1848: 1845: 1840: 1836: 1832: 1829: 1826: 1823: 1818: 1814: 1810: 1805: 1801: 1780: 1777: 1774: 1769: 1765: 1761: 1758: 1755: 1752: 1749: 1746: 1741: 1737: 1733: 1728: 1724: 1714:induces a map 1703: 1700: 1697: 1694: 1691: 1688: 1685: 1661: 1658: 1655: 1652: 1649: 1646: 1643: 1616: 1613: 1610: 1590: 1562: 1559: 1556: 1551: 1547: 1539: 1535: 1531: 1526: 1523: 1520: 1517: 1514: 1509: 1505: 1501: 1498: 1495: 1492: 1487: 1483: 1479: 1476: 1473: 1470: 1465: 1461: 1436: 1433: 1430: 1425: 1422: 1419: 1415: 1411: 1408: 1405: 1402: 1397: 1393: 1389: 1386: 1383: 1380: 1375: 1371: 1367: 1364: 1352: 1351:Interpretation 1349: 1343:is a (graded) 1329: 1328: 1317: 1314: 1311: 1308: 1303: 1299: 1295: 1292: 1289: 1286: 1281: 1277: 1273: 1270: 1267: 1264: 1261: 1258: 1253: 1249: 1230: 1229: 1218: 1215: 1212: 1207: 1203: 1199: 1196: 1193: 1190: 1185: 1181: 1177: 1172: 1168: 1153: 1152: 1141: 1138: 1135: 1132: 1129: 1104: 1103: 1092: 1087: 1083: 1079: 1074: 1070: 1066: 1061: 1058: 1054: 1050: 1047: 1044: 1041: 1036: 1032: 1028: 1023: 1019: 1003: 1000: 999: 998: 987: 984: 981: 978: 973: 970: 967: 963: 959: 956: 953: 950: 945: 941: 937: 934: 931: 928: 923: 919: 903: 902: 891: 888: 882: 878: 873: 870: 865: 861: 857: 852: 848: 844: 841: 838: 835: 830: 826: 822: 816: 812: 807: 804: 801: 796: 792: 788: 783: 779: 775: 772: 747: 743: 720: 716: 678: 675: 672: 669: 666: 663: 660: 657: 654: 651: 648: 645: 642: 638: 634: 631: 601: 598: 595: 592: 589: 586: 583: 580: 577: 573: 569: 566: 543: 540: 537: 534: 531: 528: 525: 522: 519: 516: 513: 493: 490: 487: 484: 481: 457: 454: 451: 448: 445: 442: 439: 436: 433: 430: 427: 424: 421: 418: 415: 412: 407: 403: 375: 374: 363: 358: 355: 352: 349: 346: 343: 340: 337: 334: 331: 328: 325: 322: 318: 314: 311: 308: 303: 299: 295: 292: 287: 284: 281: 278: 275: 272: 269: 266: 262: 258: 255: 252: 247: 243: 239: 236: 233: 230: 227: 222: 218: 214: 209: 205: 201: 172: 168: 158:-cochain and 141: 137: 88: 85: 63:), called the 15: 13: 10: 9: 6: 4: 3: 2: 2837: 2826: 2823: 2821: 2818: 2816: 2813: 2812: 2810: 2801: 2800:0-521-79540-0 2797: 2793: 2789: 2787: 2786:0-387-97926-3 2783: 2779: 2776: 2773: 2772:0-201-62728-0 2769: 2765: 2764:0-201-04586-9 2761: 2757: 2756: 2742: 2738: 2737: 2729: 2726: 2718: 2711: 2709: 2705: 2698: 2694: 2693:Torelli group 2691: 2689: 2686: 2684: 2681: 2679: 2676: 2674: 2671: 2670: 2666: 2664: 2662: 2658: 2652: 2644: 2640: 2636: 2629: 2627: 2625: 2620: 2598: 2595: 2587: 2584: 2581: 2577: 2573: 2568: 2560: 2557: 2554: 2548: 2543: 2535: 2529: 2524: 2516: 2505: 2489: 2485: 2481: 2476: 2472: 2468: 2463: 2455: 2449: 2444: 2436: 2425: 2424:Poincaré dual 2409: 2406: 2403: 2383: 2380: 2377: 2369: 2353: 2333: 2313: 2310: 2307: 2287: 2280:of dimension 2279: 2263: 2256:Indeed, let 2254: 2234: 2219: 2214: 2207: 2205: 2203: 2199: 2198:wedge product 2195: 2191: 2183: 2178: 2176: 2174: 2170: 2166: 2148: 2144: 2135: 2131: 2127: 2109: 2105: 2101: 2096: 2092: 2088: 2083: 2079: 2075: 2072: 2060: 2058: 2045: 2040: 2036: 2032: 2029: 2026: 2021: 2017: 2013: 2010: 2007: 1999: 1995: 1991: 1986: 1982: 1975: 1972: 1952: 1949: 1944: 1940: 1936: 1933: 1930: 1925: 1921: 1917: 1914: 1911: 1903: 1899: 1895: 1890: 1886: 1873: 1871: 1852: 1849: 1846: 1838: 1834: 1824: 1816: 1812: 1808: 1803: 1775: 1767: 1763: 1753: 1750: 1747: 1739: 1735: 1731: 1726: 1701: 1698: 1695: 1689: 1686: 1673: 1659: 1656: 1653: 1647: 1644: 1634: 1630: 1614: 1611: 1608: 1588: 1580: 1574: 1557: 1549: 1545: 1537: 1521: 1518: 1515: 1507: 1503: 1493: 1485: 1481: 1477: 1471: 1463: 1459: 1448: 1431: 1423: 1420: 1417: 1413: 1403: 1395: 1391: 1387: 1381: 1373: 1369: 1365: 1362: 1350: 1348: 1346: 1342: 1338: 1334: 1315: 1309: 1301: 1297: 1293: 1287: 1279: 1275: 1271: 1265: 1262: 1259: 1251: 1247: 1239: 1238: 1237: 1235: 1213: 1205: 1201: 1191: 1183: 1179: 1175: 1170: 1166: 1158: 1157: 1156: 1139: 1133: 1130: 1127: 1120: 1119: 1118: 1116: 1111: 1109: 1085: 1081: 1077: 1072: 1068: 1059: 1056: 1048: 1045: 1039: 1034: 1030: 1026: 1021: 1017: 1009: 1008: 1007: 1001: 985: 979: 971: 968: 965: 961: 951: 943: 939: 935: 929: 921: 917: 909: 908: 907: 889: 880: 876: 871: 868: 863: 859: 850: 842: 839: 833: 828: 824: 820: 814: 810: 805: 802: 794: 790: 786: 781: 777: 770: 763: 762: 761: 745: 741: 718: 714: 705: 700: 698: 694: 676: 673: 670: 667: 664: 661: 658: 655: 652: 649: 646: 643: 640: 636: 632: 629: 621: 617: 599: 596: 593: 590: 587: 584: 581: 578: 575: 571: 567: 564: 555: 538: 535: 532: 529: 526: 523: 520: 517: 514: 488: 485: 482: 471: 452: 449: 446: 443: 440: 437: 434: 431: 428: 425: 422: 416: 413: 410: 405: 401: 392: 388: 384: 380: 377:where σ is a 356: 353: 350: 347: 344: 341: 338: 335: 332: 329: 326: 323: 320: 316: 312: 309: 301: 297: 293: 285: 282: 279: 276: 273: 270: 267: 264: 260: 256: 253: 245: 241: 237: 231: 220: 216: 212: 207: 203: 192: 191: 190: 188: 170: 166: 157: 139: 135: 126: 121: 119: 116: 112: 108: 105: 102: 98: 94: 86: 84: 82: 78: 74: 70: 66: 62: 58: 54: 50: 46: 42: 38: 34: 30: 26: 22: 2766:(hardcover) 2745:, retrieved 2735: 2728: 2654: 2621: 2506: 2368:transversely 2255: 2252: 2187: 2172: 2168: 2164: 2129: 2125: 2064: 1874: 1674: 1576: 1450: 1354: 1340: 1336: 1332: 1330: 1234:homomorphism 1231: 1154: 1112: 1105: 1005: 904: 760:is given by 701: 696: 692: 619: 615: 557:Informally, 556: 386: 382: 376: 186: 155: 122: 117: 110: 106: 96: 90: 60: 56: 52: 48: 44: 40: 36: 28: 18: 2774:(paperback) 2683:Cap product 1870:cap product 1629:Künneth map 97:cup product 73:Eduard Čech 29:cup product 21:mathematics 2809:Categories 2747:2018-04-26 2699:References 2366:intersect 1115:functorial 1002:Properties 704:coboundary 620:front face 87:Definition 35:of degree 2574:∈ 2569:∗ 2558:∩ 2544:∗ 2530:⌣ 2525:∗ 2469:∈ 2464:∗ 2445:∗ 2381:∩ 2102:∨ 2089:∨ 2033:⌣ 2014:⌣ 1976:⌣ 1950:⌣ 1931:⌣ 1912:⌣ 1850:× 1839:∙ 1831:→ 1817:∙ 1809:: 1804:∗ 1800:Δ 1768:∙ 1760:→ 1751:× 1740:∙ 1732:: 1727:∗ 1723:Δ 1699:× 1693:→ 1687:: 1684:Δ 1657:× 1651:→ 1645:: 1642:Δ 1612:× 1550:∙ 1538:∗ 1534:Δ 1530:→ 1519:× 1508:∙ 1500:→ 1486:∙ 1478:× 1464:∙ 1410:→ 1388:× 1366:: 1363:⌣ 1310:β 1302:∗ 1294:⌣ 1288:α 1280:∗ 1266:β 1263:⌣ 1260:α 1252:∗ 1206:∗ 1198:→ 1184:∗ 1176:: 1171:∗ 1137:→ 1131:: 1082:α 1078:⌣ 1069:β 1046:− 1031:β 1027:⌣ 1018:α 958:→ 936:× 877:β 872:δ 869:⌣ 860:α 840:− 825:β 821:⌣ 811:α 806:δ 791:β 787:⌣ 778:α 771:δ 742:β 715:α 697:back face 637:ι 633:∘ 630:σ 572:ι 568:∘ 565:σ 470:embedding 417:⊂ 402:ι 317:ι 313:∘ 310:σ 298:β 294:⋅ 261:ι 257:∘ 254:σ 242:α 232:σ 217:β 213:⌣ 204:α 167:β 136:α 83:in 1944. 2741:archived 2667:See also 2134:cochains 2061:Examples 1633:diagonal 379:singular 125:cochains 33:cocycles 691:is the 614:is the 391:simplex 113:) of a 2798:  2784:  2770:  2762:  2202:closed 101:graded 95:, the 27:, the 2720:(PDF) 185:is a 154:is a 127:: if 2796:ISBN 2782:ISBN 2768:ISBN 2760:ISBN 2346:and 2216:The 1965:and 1601:and 733:and 702:The 695:-th 622:and 618:-th 393:and 75:and 39:and 2188:In 1581:of 389:) - 91:In 19:In 2811:: 2739:, 2707:^ 2619:. 2076::= 1872:. 1672:. 1347:. 1110:. 554:. 385:+ 120:. 71:, 47:+ 2722:. 2645:. 2607:) 2603:Z 2599:, 2596:X 2593:( 2588:j 2585:+ 2582:i 2578:H 2565:] 2561:B 2555:A 2552:[ 2549:= 2540:] 2536:B 2533:[ 2521:] 2517:A 2514:[ 2490:j 2486:H 2482:, 2477:i 2473:H 2460:] 2456:B 2453:[ 2450:, 2441:] 2437:A 2434:[ 2410:j 2407:+ 2404:i 2384:B 2378:A 2354:j 2334:i 2314:B 2311:, 2308:A 2288:n 2264:M 2235:3 2230:R 2173:M 2169:Z 2165:T 2149:1 2145:S 2130:X 2126:T 2110:1 2106:S 2097:1 2093:S 2084:2 2080:S 2073:X 2046:. 2041:2 2037:v 2030:u 2027:+ 2022:1 2018:v 2011:u 2008:= 2005:) 2000:2 1996:v 1992:+ 1987:1 1983:v 1979:( 1973:u 1953:v 1945:2 1941:u 1937:+ 1934:v 1926:1 1922:u 1918:= 1915:v 1909:) 1904:2 1900:u 1896:+ 1891:1 1887:u 1883:( 1856:) 1853:X 1847:X 1844:( 1835:H 1828:) 1825:X 1822:( 1813:H 1779:) 1776:X 1773:( 1764:H 1757:) 1754:X 1748:X 1745:( 1736:H 1702:X 1696:X 1690:X 1660:X 1654:X 1648:X 1615:X 1609:X 1589:X 1561:) 1558:X 1555:( 1546:C 1525:) 1522:X 1516:X 1513:( 1504:C 1497:) 1494:X 1491:( 1482:C 1475:) 1472:X 1469:( 1460:C 1435:) 1432:X 1429:( 1424:q 1421:+ 1418:p 1414:H 1407:) 1404:X 1401:( 1396:q 1392:H 1385:) 1382:X 1379:( 1374:p 1370:H 1341:f 1337:Y 1335:( 1333:H 1316:, 1313:) 1307:( 1298:f 1291:) 1285:( 1276:f 1272:= 1269:) 1257:( 1248:f 1217:) 1214:X 1211:( 1202:H 1195:) 1192:Y 1189:( 1180:H 1167:f 1140:Y 1134:X 1128:f 1091:) 1086:p 1073:q 1065:( 1060:q 1057:p 1053:) 1049:1 1043:( 1040:= 1035:q 1022:p 986:. 983:) 980:X 977:( 972:q 969:+ 966:p 962:H 955:) 952:X 949:( 944:q 940:H 933:) 930:X 927:( 922:p 918:H 890:. 887:) 881:q 864:p 856:( 851:p 847:) 843:1 837:( 834:+ 829:q 815:p 803:= 800:) 795:q 782:p 774:( 746:q 719:p 693:q 677:q 674:+ 671:p 668:, 665:. 662:. 659:. 656:, 653:1 650:+ 647:p 644:, 641:p 616:p 600:p 597:, 594:. 591:. 588:. 585:, 582:1 579:, 576:0 542:} 539:q 536:+ 533:p 530:, 527:. 524:. 521:. 518:, 515:0 512:{ 492:) 489:q 486:+ 483:p 480:( 456:} 453:q 450:+ 447:p 444:, 441:. 438:. 435:. 432:, 429:1 426:, 423:0 420:{ 414:S 411:, 406:S 387:q 383:p 381:( 362:) 357:q 354:+ 351:p 348:, 345:. 342:. 339:. 336:, 333:1 330:+ 327:p 324:, 321:p 307:( 302:q 291:) 286:p 283:. 280:. 277:. 274:, 271:1 268:, 265:0 251:( 246:p 238:= 235:) 229:( 226:) 221:q 208:p 200:( 187:q 171:q 156:p 140:p 118:X 111:X 109:( 107:H 61:X 59:( 57:H 53:X 49:q 45:p 41:q 37:p

Index

mathematics
algebraic topology
cocycles
cohomology ring
J. W. Alexander
Eduard Čech
Hassler Whitney
Samuel Eilenberg
singular cohomology
graded
cohomology ring
topological space
cochains
singular
simplex
embedding
coboundary
graded-commutative
functorial
homomorphism
ring homomorphism
chain complexes
Künneth map
diagonal
cap product
cochains
de Rham cohomology
differential forms
wedge product
closed

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