Knowledge (XXG)

Constructible set (topology)

Source đź“ť

1136: 1008: 602:. In the second edition of EGA constructible sets (according to the definition above) are called "globally constructible" while the word "constructible" is reserved for what are called locally constructible above. 572:
subsets are retrocompact, and so for such spaces the simplified definition given first above is equivalent to the more elaborate one. Most of the commonly met schemes in algebraic geometry (including all
776: 59:). In addition, a large number of "local" geometric properties of schemes, morphisms and sheaves are (locally) constructible. Constructible sets also feature in the definition of various types of 1634: 899: 1943: 1753: 1509: 1318: 1171: 954: 561:
and finite unions (and hence also finite intersections) of sets in it. In other words, constructible sets are precisely the Boolean algebra generated by retrocompact open subsets.
1283: 1226: 1039: 920:
on schemes hold true over a locally constructible subset. EGA IV § 9 covers a large number of such properties. Below are some examples (where all references point to EGA IV):
408: 1415: 535: 1195: 2107: 2065: 2043: 1908: 1866: 1718: 1676: 461: 265: 1969: 1779: 1555: 1344: 680: 355: 199: 1844: 1454: 1070: 650: 169: 1995: 1805: 1581: 1370: 1252: 1065: 843: 808: 488: 709: 595: 2085: 1886: 1696: 1654: 1529: 1477: 729: 555: 511: 428: 329: 305: 285: 219: 139: 119: 2515: 2473: 2431: 959: 734:
In particular, the image of an algebraic variety need not be a variety, but is (under the assumptions) always a constructible set. For example, the map
1720:
is any of the following properties: surjective, proper, finite, immersion, closed immersion, open immersion, isomorphism. (Proposition (9.6.1))
2564: 565: 95:.) However, a modification and another slightly weaker definition are needed to have definitions that behave better with "large" spaces: 904:
Chevalley's theorem in the generality stated above would fail if the simplified definition of constructible sets (without restricting to
2391: 2556: 737: 2113:
One important role that these constructibility results have is that in most cases assuming the morphisms in questions are also
1910:
is any of the following properties: geometrically irreducible, geometrically connected, geometrically reduced. (Theorem (9.7.7))
614:
of a (locally) constructible set is also (locally) constructible for a large class of maps (or "morphisms"). The key result is:
2382:. Ergebnisse der Mathematik und ihrer Grenzgebiete (3) --- Results in Mathematics and Related Areas (3). Vol. 33. Berlin: 2109:
is any of the following properties: geometrically regular, geometrically normal, geometrically reduced. (Proposition (9.9.4))
653: 2582: 1586: 2631: 84: 2581:. Studies in Logic and the Foundations of Mathematics. Amsterdam --- Warsaw: North-Holland Publishing Co. ---- 2511:"ÉlĂ©ments de gĂ©omĂ©trie algĂ©brique: IV. Étude locale des schĂ©mas et des morphismes de schĂ©mas, Troisième partie" 848: 2469:"ÉlĂ©ments de gĂ©omĂ©trie algĂ©brique: IV. Étude locale des schĂ©mas et des morphismes de schĂ©mas, Première partie" 2555:. Grundlehren der Mathematischen Wissenschaften (in French). Vol. 166 (2nd ed.). Berlin; New York: 43:
in algebraic geometry shows that the image of a constructible set is constructible for an important class of
1916: 1726: 1482: 1291: 1144: 927: 558: 64: 2370: 2544: 2502: 2460: 2418: 2130: 17: 1257: 1200: 1013: 367: 2427:"Eléments de géométrie algébrique: III. Étude cohomologique des faisceaux cohérents, Première partie" 1375: 516: 56: 1176: 2135: 917: 611: 577:) are locally Noetherian, but there are important constructions that lead to more general schemes. 60: 52: 48: 2090: 2048: 2000: 1891: 1849: 1701: 1659: 1131:{\displaystyle {\mathcal {F}}'_{s}\rightarrow {\mathcal {F}}_{s}\rightarrow {\mathcal {F}}''_{s}} 433: 232: 80: 76: 36: 1948: 1758: 1534: 1323: 659: 334: 178: 1810: 1420: 2626: 2574: 2560: 2548: 2506: 2464: 2422: 2387: 623: 574: 44: 32: 148: 2524: 2482: 2440: 1974: 1784: 1560: 1349: 1231: 1044: 813: 581: 362: 2590: 2536: 2494: 2452: 2401: 781: 466: 2586: 2532: 2490: 2448: 2397: 2383: 685: 610:
A major reason for the importance of constructible sets in algebraic geometry is that the
75:
A simple definition, adequate in many situations, is that a constructible set is a finite
2070: 1871: 1681: 1639: 1514: 1462: 714: 599: 540: 496: 413: 314: 290: 270: 204: 124: 104: 2510: 2620: 2114: 1003:{\displaystyle {\mathcal {F}}'\rightarrow {\mathcal {F}}\rightarrow {\mathcal {F}}''} 172: 2408: 2468: 2426: 2355:, § 12 Étude des fibres des morphismes plats de présentation finie, pp. 173-187. 2613:
Constructibility properties of morphisms of schemes (incl. Chevalley's theorem)
2217: 92: 2610: 2604: 2309: 2269: 2174: 1945:
be an locally finitely presented morphism of schemes and consider the set
585: 2121:
subset. A substantial number of such results is included in EGA IV § 12.
88: 35:
that have a relatively "simple" structure. They are used particularly in
24: 2218:"Rigid geometric structures, isometric actions, and algebraic quotients" 2528: 2486: 2444: 557:
that (i) contains all open retrocompact subsets and (ii) contains all
1755:
be an finitely presented morphism of schemes and consider the set
594:
The definition given here is the one used by the first edition of
916:
A large number of "local" properties of morphisms of schemes and
2378:
Andradas, Carlos; Bröcker, Ludwig; Ruiz, JesĂşs M. (1996).
1285:
is locally free is locally constructible. (Proposition (9.4.7))
2117:
it follows that the properties in question in fact hold in an
493:
Equivalently the constructible subsets of a topological space
2310:"Section 109.24 Images of locally closed subsets (tag 0GZL)" 1264: 1207: 1182: 1114: 1097: 1077: 1020: 991: 980: 966: 771:{\displaystyle \mathbf {A} ^{2}\rightarrow \mathbf {A} ^{2}} 2553:Éléments de géométrie algébrique: I. Le langage des schémas 1138:
is exact is locally constructible. (Proposition (9.4.4))
584:) topological space, every constructible set contains a 430:
consisting of open subsets with the property that each
2243:, DĂ©finitions (2.3.1), (2.3.2) and (2.3.10), pp. 55-57 2164:, DĂ©finitions (9.1.1), (9.1.2) and (9.1.11), pp. 12-14 2371:
Note on the constructible sets of a topological space
2348: 2332: 2292: 2252: 2233: 2197: 2154: 2093: 2073: 2051: 2003: 1977: 1951: 1919: 1894: 1874: 1852: 1813: 1787: 1761: 1729: 1704: 1684: 1662: 1642: 1589: 1563: 1537: 1517: 1485: 1465: 1423: 1378: 1352: 1326: 1294: 1260: 1234: 1203: 1179: 1147: 1073: 1047: 1016: 962: 930: 851: 816: 784: 740: 717: 688: 662: 626: 543: 519: 499: 469: 436: 416: 370: 337: 317: 293: 273: 235: 207: 181: 151: 127: 107: 1346:is a locally constructible subset, then the set of 1010:is a sequence of finitely presented quasi-coherent 2607:Topological definition of (local) constructibility 2270:"Theorem 29.22.3 (Chevalley's Theorem) (tag 054K)" 2101: 2079: 2059: 2037: 1989: 1963: 1937: 1902: 1880: 1860: 1838: 1799: 1773: 1747: 1712: 1690: 1670: 1648: 1629:{\displaystyle f_{s}\colon X_{s}\rightarrow Y_{s}} 1628: 1575: 1549: 1523: 1503: 1471: 1448: 1409: 1364: 1338: 1312: 1277: 1246: 1220: 1189: 1165: 1130: 1059: 1033: 1002: 948: 893: 837: 802: 770: 723: 703: 674: 644: 549: 529: 505: 482: 455: 422: 402: 349: 323: 299: 279: 259: 213: 193: 163: 133: 113: 1320:is an finitely presented morphism of schemes and 1173:is an finitely presented morphism of schemes and 956:is an finitely presented morphism of schemes and 901:, which is not a variety, but is constructible. 1456:is locally constructible. (Corollary (9.5.4)) 8: 888: 870: 864: 852: 2339:, § 9 PropriĂ©tĂ©s constructibles, pp. 54-94. 39:and related fields. A key result known as 2611:https://stacks.math.columbia.edu/tag/054H 2605:https://stacks.math.columbia.edu/tag/04ZC 2094: 2092: 2072: 2052: 2050: 2008: 2002: 1976: 1950: 1918: 1895: 1893: 1873: 1853: 1851: 1818: 1812: 1786: 1760: 1728: 1705: 1703: 1683: 1663: 1661: 1641: 1620: 1607: 1594: 1588: 1562: 1536: 1516: 1484: 1464: 1428: 1422: 1383: 1377: 1351: 1325: 1293: 1269: 1263: 1262: 1259: 1233: 1212: 1206: 1205: 1202: 1181: 1180: 1178: 1146: 1119: 1113: 1112: 1102: 1096: 1095: 1082: 1076: 1075: 1072: 1046: 1025: 1019: 1018: 1015: 990: 989: 979: 978: 965: 964: 961: 929: 894:{\displaystyle \{x\neq 0\}\cup \{x=y=0\}} 850: 815: 783: 762: 757: 747: 742: 739: 716: 687: 661: 625: 542: 521: 520: 518: 498: 474: 468: 447: 435: 415: 388: 378: 369: 336: 316: 292: 272: 234: 206: 180: 150: 126: 106: 908:open sets in the definition) were used. 682:is a locally constructible subset, then 83:. (A set is locally closed if it is the 2147: 1197:is a finitely presented quasi-coherent 1938:{\displaystyle f\colon X\rightarrow S} 1748:{\displaystyle f\colon X\rightarrow S} 1504:{\displaystyle f\colon X\rightarrow Y} 1313:{\displaystyle f\colon X\rightarrow S} 1166:{\displaystyle f\colon X\rightarrow S} 949:{\displaystyle f\colon X\rightarrow S} 7: 2579:Constructible sets with applications 2516:Publications MathĂ©matiques de l'IHÉS 2474:Publications MathĂ©matiques de l'IHÉS 2432:Publications MathĂ©matiques de l'IHÉS 566:locally noetherian topological space 2380:Constructible sets in real geometry 522: 1278:{\displaystyle {\mathcal {F}}_{s}} 1221:{\displaystyle {\mathcal {O}}_{X}} 1034:{\displaystyle {\mathcal {O}}_{X}} 16:For a Gödel constructive set, see 14: 2349:Grothendieck & DieudonnĂ© 1966 2333:Grothendieck & DieudonnĂ© 1966 2293:Grothendieck & DieudonnĂ© 1971 2253:Grothendieck & DieudonnĂ© 1964 2234:Grothendieck & DieudonnĂ© 1971 2198:Grothendieck & DieudonnĂ© 1961 2155:Grothendieck & DieudonnĂ© 1961 711:is also locally constructible in 2583:PWN-Polish Scientific Publishers 2095: 2053: 1896: 1854: 1706: 1664: 758: 743: 403:{\displaystyle (U_{i})_{i\in I}} 1583:for which the induced morphism 1410:{\displaystyle f^{-1}(s)\cap Z} 530:{\displaystyle {\mathfrak {C}}} 2175:"Definition 5.15.1 (tag 005G)" 2032: 2029: 2023: 2017: 1929: 1833: 1827: 1739: 1613: 1495: 1443: 1437: 1398: 1392: 1304: 1190:{\displaystyle {\mathcal {F}}} 1157: 1108: 1091: 985: 975: 940: 832: 817: 797: 785: 753: 698: 692: 636: 385: 371: 254: 242: 175:for every compact open subset 1: 463:is a constructible subset of 229:union of subsets of the form 2102:{\displaystyle \mathbf {P} } 2087:is locally constructible if 2060:{\displaystyle \mathbf {P} } 2038:{\displaystyle f^{-1}(f(x))} 1903:{\displaystyle \mathbf {P} } 1888:is locally constructible if 1861:{\displaystyle \mathbf {P} } 1713:{\displaystyle \mathbf {P} } 1698:is locally constructible if 1671:{\displaystyle \mathbf {P} } 1531:-schemes. Consider the set 588:open subset of its closure. 513:are the smallest collection 31:are a class of subsets of a 2299:, ThĂ©orème (7.1.4), p. 329. 2259:, ThĂ©orème (1.8.4), p. 239. 456:{\displaystyle Z\cap U_{i}} 260:{\displaystyle U\cap (X-V)} 2648: 1964:{\displaystyle P\subset X} 1774:{\displaystyle P\subset S} 1550:{\displaystyle P\subset S} 1339:{\displaystyle Z\subset X} 1041:-modules, then the set of 675:{\displaystyle Z\subset X} 350:{\displaystyle Z\subset X} 194:{\displaystyle U\subset X} 63:in algebraic geometry and 15: 1839:{\displaystyle f^{-1}(s)} 1449:{\displaystyle f^{-1}(s)} 1228:-module, then the set of 2413:Linear algebraic groups. 2314:stacks.math.columbia.edu 2274:stacks.math.columbia.edu 2179:stacks.math.columbia.edu 912:Constructible properties 656:morphism of schemes and 645:{\displaystyle f:X\to Y} 580:In any (not necessarily 2545:Grothendieck, Alexandre 2503:Grothendieck, Alexandre 2461:Grothendieck, Alexandre 2419:Grothendieck, Alexandre 1417:is closed (or open) in 605: 164:{\displaystyle Z\cap U} 121:of a topological space 65:intersection cohomology 2131:Constructible topology 2103: 2081: 2061: 2039: 1991: 1990:{\displaystyle x\in X} 1965: 1939: 1904: 1882: 1862: 1840: 1801: 1800:{\displaystyle s\in S} 1775: 1749: 1714: 1692: 1672: 1650: 1630: 1577: 1576:{\displaystyle s\in S} 1551: 1525: 1505: 1473: 1450: 1411: 1366: 1365:{\displaystyle s\in S} 1340: 1314: 1279: 1248: 1247:{\displaystyle s\in S} 1222: 1191: 1167: 1132: 1061: 1060:{\displaystyle s\in S} 1035: 1004: 950: 895: 839: 838:{\displaystyle (x,xy)} 804: 772: 725: 705: 676: 646: 551: 531: 507: 484: 457: 424: 404: 351: 325: 301: 281: 261: 215: 195: 165: 135: 115: 18:Constructible universe 2368:Allouche, Jean Paul. 2104: 2082: 2062: 2040: 1992: 1966: 1940: 1905: 1883: 1863: 1841: 1802: 1776: 1750: 1715: 1693: 1673: 1651: 1631: 1578: 1552: 1526: 1506: 1474: 1451: 1412: 1367: 1341: 1315: 1280: 1249: 1223: 1192: 1168: 1133: 1062: 1036: 1005: 951: 918:quasicoherent sheaves 896: 840: 805: 803:{\displaystyle (x,y)} 773: 726: 706: 677: 647: 552: 532: 508: 485: 483:{\displaystyle U_{i}} 458: 425: 405: 359:locally constructible 352: 326: 302: 282: 262: 216: 196: 166: 136: 116: 61:constructible sheaves 2207:, Sect. (9.1), p. 12 2091: 2071: 2049: 2001: 1997:for which the fibre 1975: 1949: 1917: 1892: 1872: 1850: 1811: 1807:for which the fibre 1785: 1759: 1727: 1702: 1682: 1660: 1640: 1587: 1561: 1535: 1515: 1483: 1463: 1421: 1376: 1350: 1324: 1292: 1258: 1232: 1201: 1177: 1145: 1071: 1045: 1014: 960: 928: 849: 814: 782: 738: 715: 704:{\displaystyle f(Z)} 686: 660: 624: 618:Chevalley's theorem. 541: 517: 497: 467: 434: 414: 368: 335: 315: 291: 271: 233: 205: 179: 149: 125: 105: 2585:. pp. ix+269. 2216:Jinpeng An (2012). 2136:Constructible sheaf 1127: 1090: 606:Chevalley's theorem 575:algebraic varieties 81:locally closed sets 55:(or more generally 53:algebraic varieties 47:(more specifically 41:Chevalley's theorem 2632:Algebraic geometry 2529:10.1007/bf02684343 2487:10.1007/bf02684747 2445:10.1007/bf02684274 2386:. pp. x+270. 2099: 2077: 2057: 2035: 1987: 1961: 1935: 1900: 1878: 1858: 1836: 1797: 1771: 1745: 1710: 1688: 1668: 1656:has some property 1646: 1626: 1573: 1547: 1521: 1501: 1469: 1446: 1407: 1362: 1336: 1310: 1275: 1244: 1218: 1187: 1163: 1128: 1111: 1074: 1057: 1031: 1000: 946: 891: 845:has image the set 835: 800: 768: 721: 701: 672: 654:finitely presented 642: 547: 527: 503: 480: 453: 420: 400: 347: 321: 297: 277: 257: 211: 191: 161: 131: 111: 37:algebraic geometry 29:constructible sets 2566:978-3-540-05113-8 2220:. Geom. Dedicata 2080:{\displaystyle P} 1881:{\displaystyle P} 1691:{\displaystyle P} 1649:{\displaystyle s} 1524:{\displaystyle S} 1472:{\displaystyle S} 724:{\displaystyle Y} 550:{\displaystyle X} 506:{\displaystyle X} 423:{\displaystyle X} 324:{\displaystyle X} 300:{\displaystyle V} 280:{\displaystyle U} 214:{\displaystyle X} 134:{\displaystyle X} 114:{\displaystyle Z} 33:topological space 2639: 2594: 2570: 2540: 2498: 2456: 2405: 2356: 2346: 2340: 2330: 2324: 2323: 2321: 2320: 2306: 2300: 2290: 2284: 2283: 2281: 2280: 2266: 2260: 2250: 2244: 2231: 2225: 2214: 2208: 2195: 2189: 2188: 2186: 2185: 2171: 2165: 2152: 2108: 2106: 2105: 2100: 2098: 2086: 2084: 2083: 2078: 2066: 2064: 2063: 2058: 2056: 2044: 2042: 2041: 2036: 2016: 2015: 1996: 1994: 1993: 1988: 1970: 1968: 1967: 1962: 1944: 1942: 1941: 1936: 1909: 1907: 1906: 1901: 1899: 1887: 1885: 1884: 1879: 1867: 1865: 1864: 1859: 1857: 1845: 1843: 1842: 1837: 1826: 1825: 1806: 1804: 1803: 1798: 1780: 1778: 1777: 1772: 1754: 1752: 1751: 1746: 1719: 1717: 1716: 1711: 1709: 1697: 1695: 1694: 1689: 1677: 1675: 1674: 1669: 1667: 1655: 1653: 1652: 1647: 1635: 1633: 1632: 1627: 1625: 1624: 1612: 1611: 1599: 1598: 1582: 1580: 1579: 1574: 1556: 1554: 1553: 1548: 1530: 1528: 1527: 1522: 1510: 1508: 1507: 1502: 1479:be a scheme and 1478: 1476: 1475: 1470: 1455: 1453: 1452: 1447: 1436: 1435: 1416: 1414: 1413: 1408: 1391: 1390: 1371: 1369: 1368: 1363: 1345: 1343: 1342: 1337: 1319: 1317: 1316: 1311: 1284: 1282: 1281: 1276: 1274: 1273: 1268: 1267: 1253: 1251: 1250: 1245: 1227: 1225: 1224: 1219: 1217: 1216: 1211: 1210: 1196: 1194: 1193: 1188: 1186: 1185: 1172: 1170: 1169: 1164: 1137: 1135: 1134: 1129: 1123: 1118: 1117: 1107: 1106: 1101: 1100: 1086: 1081: 1080: 1066: 1064: 1063: 1058: 1040: 1038: 1037: 1032: 1030: 1029: 1024: 1023: 1009: 1007: 1006: 1001: 999: 995: 994: 984: 983: 974: 970: 969: 955: 953: 952: 947: 900: 898: 897: 892: 844: 842: 841: 836: 809: 807: 806: 801: 777: 775: 774: 769: 767: 766: 761: 752: 751: 746: 730: 728: 727: 722: 710: 708: 707: 702: 681: 679: 678: 673: 651: 649: 648: 643: 556: 554: 553: 548: 536: 534: 533: 528: 526: 525: 512: 510: 509: 504: 489: 487: 486: 481: 479: 478: 462: 460: 459: 454: 452: 451: 429: 427: 426: 421: 409: 407: 406: 401: 399: 398: 383: 382: 356: 354: 353: 348: 330: 328: 327: 322: 309:and retrocompact 306: 304: 303: 298: 286: 284: 283: 278: 266: 264: 263: 258: 220: 218: 217: 212: 200: 198: 197: 192: 170: 168: 167: 162: 140: 138: 137: 132: 120: 118: 117: 112: 2647: 2646: 2642: 2641: 2640: 2638: 2637: 2636: 2617: 2616: 2601: 2573: 2567: 2557:Springer-Verlag 2549:DieudonnĂ©, Jean 2543: 2507:DieudonnĂ©, Jean 2501: 2465:DieudonnĂ©, Jean 2459: 2423:DieudonnĂ©, Jean 2417: 2394: 2384:Springer-Verlag 2377: 2365: 2360: 2359: 2347: 2343: 2331: 2327: 2318: 2316: 2308: 2307: 2303: 2291: 2287: 2278: 2276: 2268: 2267: 2263: 2251: 2247: 2242: 2232: 2228: 2215: 2211: 2206: 2196: 2192: 2183: 2181: 2173: 2172: 2168: 2163: 2153: 2149: 2144: 2127: 2089: 2088: 2069: 2068: 2047: 2046: 2045:has a property 2004: 1999: 1998: 1973: 1972: 1947: 1946: 1915: 1914: 1890: 1889: 1870: 1869: 1848: 1847: 1846:has a property 1814: 1809: 1808: 1783: 1782: 1757: 1756: 1725: 1724: 1700: 1699: 1680: 1679: 1658: 1657: 1638: 1637: 1636:of fibres over 1616: 1603: 1590: 1585: 1584: 1559: 1558: 1533: 1532: 1513: 1512: 1481: 1480: 1461: 1460: 1424: 1419: 1418: 1379: 1374: 1373: 1348: 1347: 1322: 1321: 1290: 1289: 1261: 1256: 1255: 1230: 1229: 1204: 1199: 1198: 1175: 1174: 1143: 1142: 1094: 1069: 1068: 1043: 1042: 1017: 1012: 1011: 988: 963: 958: 957: 926: 925: 914: 847: 846: 812: 811: 780: 779: 756: 741: 736: 735: 713: 712: 684: 683: 658: 657: 622: 621: 608: 539: 538: 515: 514: 495: 494: 470: 465: 464: 443: 432: 431: 412: 411: 384: 374: 366: 365: 333: 332: 313: 312: 289: 288: 269: 268: 231: 230: 203: 202: 177: 176: 147: 146: 123: 122: 103: 102: 73: 21: 12: 11: 5: 2645: 2643: 2635: 2634: 2629: 2619: 2618: 2615: 2614: 2608: 2600: 2599:External links 2597: 2596: 2595: 2571: 2565: 2541: 2499: 2457: 2415: 2406: 2392: 2375: 2364: 2361: 2358: 2357: 2341: 2325: 2301: 2285: 2261: 2245: 2240: 2226: 2209: 2204: 2190: 2166: 2161: 2146: 2145: 2143: 2140: 2139: 2138: 2133: 2126: 2123: 2111: 2110: 2097: 2076: 2055: 2034: 2031: 2028: 2025: 2022: 2019: 2014: 2011: 2007: 1986: 1983: 1980: 1960: 1957: 1954: 1934: 1931: 1928: 1925: 1922: 1911: 1898: 1877: 1856: 1835: 1832: 1829: 1824: 1821: 1817: 1796: 1793: 1790: 1770: 1767: 1764: 1744: 1741: 1738: 1735: 1732: 1721: 1708: 1687: 1666: 1645: 1623: 1619: 1615: 1610: 1606: 1602: 1597: 1593: 1572: 1569: 1566: 1546: 1543: 1540: 1520: 1511:a morphism of 1500: 1497: 1494: 1491: 1488: 1468: 1457: 1445: 1442: 1439: 1434: 1431: 1427: 1406: 1403: 1400: 1397: 1394: 1389: 1386: 1382: 1361: 1358: 1355: 1335: 1332: 1329: 1309: 1306: 1303: 1300: 1297: 1286: 1272: 1266: 1243: 1240: 1237: 1215: 1209: 1184: 1162: 1159: 1156: 1153: 1150: 1139: 1126: 1122: 1116: 1110: 1105: 1099: 1093: 1089: 1085: 1079: 1056: 1053: 1050: 1028: 1022: 998: 993: 987: 982: 977: 973: 968: 945: 942: 939: 936: 933: 913: 910: 890: 887: 884: 881: 878: 875: 872: 869: 866: 863: 860: 857: 854: 834: 831: 828: 825: 822: 819: 799: 796: 793: 790: 787: 765: 760: 755: 750: 745: 720: 700: 697: 694: 691: 671: 668: 665: 641: 638: 635: 632: 629: 607: 604: 600:Stacks Project 546: 537:of subsets of 524: 502: 477: 473: 450: 446: 442: 439: 419: 397: 394: 391: 387: 381: 377: 373: 361:if there is a 346: 343: 340: 320: 296: 276: 256: 253: 250: 247: 244: 241: 238: 210: 201:. A subset of 190: 187: 184: 160: 157: 154: 130: 110: 72: 69: 13: 10: 9: 6: 4: 3: 2: 2644: 2633: 2630: 2628: 2625: 2624: 2622: 2612: 2609: 2606: 2603: 2602: 2598: 2592: 2588: 2584: 2580: 2576: 2575:Mostowski, A. 2572: 2568: 2562: 2558: 2554: 2550: 2546: 2542: 2538: 2534: 2530: 2526: 2522: 2518: 2517: 2512: 2508: 2504: 2500: 2496: 2492: 2488: 2484: 2480: 2476: 2475: 2470: 2466: 2462: 2458: 2454: 2450: 2446: 2442: 2438: 2434: 2433: 2428: 2424: 2420: 2416: 2414: 2410: 2409:Borel, Armand 2407: 2403: 2399: 2395: 2393:3-540-60451-0 2389: 2385: 2381: 2376: 2374: 2372: 2367: 2366: 2362: 2354: 2350: 2345: 2342: 2338: 2334: 2329: 2326: 2315: 2311: 2305: 2302: 2298: 2294: 2289: 2286: 2275: 2271: 2265: 2262: 2258: 2254: 2249: 2246: 2239: 2235: 2230: 2227: 2223: 2219: 2213: 2210: 2203: 2199: 2194: 2191: 2180: 2176: 2170: 2167: 2160: 2156: 2151: 2148: 2141: 2137: 2134: 2132: 2129: 2128: 2124: 2122: 2120: 2116: 2074: 2026: 2020: 2012: 2009: 2005: 1984: 1981: 1978: 1958: 1955: 1952: 1932: 1926: 1923: 1920: 1912: 1875: 1830: 1822: 1819: 1815: 1794: 1791: 1788: 1768: 1765: 1762: 1742: 1736: 1733: 1730: 1722: 1685: 1643: 1621: 1617: 1608: 1604: 1600: 1595: 1591: 1570: 1567: 1564: 1544: 1541: 1538: 1518: 1498: 1492: 1489: 1486: 1466: 1458: 1440: 1432: 1429: 1425: 1404: 1401: 1395: 1387: 1384: 1380: 1359: 1356: 1353: 1333: 1330: 1327: 1307: 1301: 1298: 1295: 1287: 1270: 1241: 1238: 1235: 1213: 1160: 1154: 1151: 1148: 1140: 1124: 1120: 1103: 1087: 1083: 1054: 1051: 1048: 1026: 996: 971: 943: 937: 934: 931: 923: 922: 921: 919: 911: 909: 907: 902: 885: 882: 879: 876: 873: 867: 861: 858: 855: 829: 826: 823: 820: 794: 791: 788: 763: 748: 732: 718: 695: 689: 669: 666: 663: 655: 639: 633: 630: 627: 619: 615: 613: 603: 601: 597: 593: 589: 587: 583: 578: 576: 571: 567: 562: 560: 544: 500: 491: 475: 471: 448: 444: 440: 437: 417: 395: 392: 389: 379: 375: 364: 360: 344: 341: 338: 318: 310: 294: 274: 251: 248: 245: 239: 236: 228: 224: 223:constructible 208: 188: 185: 182: 174: 158: 155: 152: 144: 128: 108: 100: 96: 94: 90: 86: 82: 78: 70: 68: 66: 62: 58: 54: 50: 46: 42: 38: 34: 30: 26: 19: 2578: 2552: 2520: 2514: 2478: 2472: 2436: 2430: 2412: 2379: 2369: 2352: 2344: 2336: 2328: 2317:. Retrieved 2313: 2304: 2296: 2288: 2277:. Retrieved 2273: 2264: 2256: 2248: 2237: 2229: 2221: 2212: 2201: 2193: 2182:. Retrieved 2178: 2169: 2158: 2150: 2118: 2112: 915: 906:retrocompact 905: 903: 733: 617: 616: 609: 592:Terminology: 591: 590: 579: 569: 563: 492: 358: 331:. A subset 308: 226: 222: 143:retrocompact 142: 99:Definitions: 98: 97: 85:intersection 74: 40: 28: 22: 778:that sends 559:complements 311:subsets of 267:where both 225:if it is a 71:Definitions 2621:Categories 2363:References 2319:2022-10-04 2279:2022-10-04 2224:: 153–185. 2184:2022-10-04 1372:for which 1254:for which 1067:for which 582:noetherian 141:is called 93:closed set 2010:− 1982:∈ 1956:⊂ 1930:→ 1924:: 1820:− 1792:∈ 1766:⊂ 1740:→ 1734:: 1614:→ 1601:: 1568:∈ 1542:⊂ 1496:→ 1490:: 1430:− 1402:∩ 1385:− 1357:∈ 1331:⊂ 1305:→ 1299:: 1239:∈ 1158:→ 1152:: 1109:→ 1092:→ 1052:∈ 986:→ 976:→ 941:→ 935:: 868:∪ 859:≠ 754:→ 667:⊂ 637:→ 441:∩ 393:∈ 342:⊂ 307:are open 249:− 240:∩ 186:⊂ 156:∩ 101:A subset 49:morphisms 2627:Topology 2577:(1969). 2551:(1971). 2509:(1966). 2467:(1964). 2425:(1961). 2125:See also 1125:″ 1088:′ 997:″ 972:′ 598:and the 89:open set 45:mappings 25:topology 2591:0255390 2537:0217086 2495:0173675 2453:0217085 2402:1393194 2067:. Then 1868:. Then 1678:. Then 173:compact 57:schemes 2589:  2563:  2535:  2493:  2451:  2400:  2390:  2351:, Ch. 2335:, Ch. 2295:, Ch. 2255:, Ch. 2236:, Ch. 2200:, Ch. 2157:, Ch. 227:finite 87:of an 2142:Notes 652:is a 612:image 586:dense 564:In a 363:cover 77:union 51:) of 2561:ISBN 2388:ISBN 2119:open 2115:flat 1913:Let 1723:Let 1459:Let 287:and 91:and 2525:doi 2483:doi 2441:doi 2222:157 2205:III 2162:III 1971:of 1781:of 1557:of 1288:If 1141:If 924:If 810:to 620:If 596:EGA 570:all 490:. 410:of 357:is 221:is 171:is 145:if 79:of 23:In 2623:: 2587:MR 2559:. 2547:; 2533:MR 2531:. 2523:. 2521:28 2519:. 2513:. 2505:; 2491:MR 2489:. 2481:. 2479:20 2477:. 2471:. 2463:; 2449:MR 2447:. 2439:. 2437:11 2435:. 2429:. 2421:; 2411:. 2398:MR 2396:. 2353:IV 2337:IV 2312:. 2272:. 2177:. 731:. 568:, 67:. 27:, 2593:. 2569:. 2539:. 2527:: 2497:. 2485:: 2455:. 2443:: 2404:. 2373:. 2322:. 2297:I 2282:. 2257:I 2241:I 2238:0 2202:0 2187:. 2159:0 2096:P 2075:P 2054:P 2033:) 2030:) 2027:x 2024:( 2021:f 2018:( 2013:1 2006:f 1985:X 1979:x 1959:X 1953:P 1933:S 1927:X 1921:f 1897:P 1876:P 1855:P 1834:) 1831:s 1828:( 1823:1 1816:f 1795:S 1789:s 1769:S 1763:P 1743:S 1737:X 1731:f 1707:P 1686:P 1665:P 1644:s 1622:s 1618:Y 1609:s 1605:X 1596:s 1592:f 1571:S 1565:s 1545:S 1539:P 1519:S 1499:Y 1493:X 1487:f 1467:S 1444:) 1441:s 1438:( 1433:1 1426:f 1405:Z 1399:) 1396:s 1393:( 1388:1 1381:f 1360:S 1354:s 1334:X 1328:Z 1308:S 1302:X 1296:f 1271:s 1265:F 1242:S 1236:s 1214:X 1208:O 1183:F 1161:S 1155:X 1149:f 1121:s 1115:F 1104:s 1098:F 1084:s 1078:F 1055:S 1049:s 1027:X 1021:O 992:F 981:F 967:F 944:S 938:X 932:f 889:} 886:0 883:= 880:y 877:= 874:x 871:{ 865:} 862:0 856:x 853:{ 833:) 830:y 827:x 824:, 821:x 818:( 798:) 795:y 792:, 789:x 786:( 764:2 759:A 749:2 744:A 719:Y 699:) 696:Z 693:( 690:f 670:X 664:Z 640:Y 634:X 631:: 628:f 545:X 523:C 501:X 476:i 472:U 449:i 445:U 438:Z 418:X 396:I 390:i 386:) 380:i 376:U 372:( 345:X 339:Z 319:X 295:V 275:U 255:) 252:V 246:X 243:( 237:U 209:X 189:X 183:U 159:U 153:Z 129:X 109:Z 20:.

Index

Constructible universe
topology
topological space
algebraic geometry
mappings
morphisms
algebraic varieties
schemes
constructible sheaves
intersection cohomology
union
locally closed sets
intersection
open set
closed set
compact
cover
complements
locally noetherian topological space
algebraic varieties
noetherian
dense
EGA
Stacks Project
image
finitely presented
quasicoherent sheaves
flat
Constructible topology
Constructible sheaf

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

↑