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Algebraic geometry of projective spaces

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The Proj construction in fact gives more than a mere scheme: a sheaf in graded modules over the structure sheaf is defined in the process. The homogeneous components of this graded sheaf are denoted
1269: 1042: 840: 2034: 1397: 659:, which shows that any Weil divisor is linearly equivalent to some power of a hyperplane divisor. This consideration proves that the Picard group of a projective space is free of rank 1. That is 1580: 1145: 1528: 1459: 944: 1709: 1621: 772: 1752: 1317: 305: 117:) is non-trivial (i.e. the common zero locus contains more than the single element {0}), and, more precisely, the ideal of polynomials that vanish on that locus coincides with the 878: 1760: 2093: 1484: 1212: 977: 638: 593: 542: 900: 445: 2193: 497:
It can be noted that the ring of global sections of this scheme is a field, which implies that the scheme is not affine. Any two open sets intersect non-trivially:
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the projective schemes can be thought of as being obtained by the gluing via projectivization of isomorphic affine schemes.
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to a projective space. A line bundle whose base can be embedded in a projective space by such a morphism is called
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states that on the projective line, any vector bundle splits in a unique way as a direct sum of the line bundles.
1409: 912: 2390: 1673: 1585: 1151: 739: 1870:{\displaystyle j^{*}(\Gamma (\mathbf {P} ^{n},{\mathcal {O}}(1)))\subset \Gamma (X,j^{*}{\mathcal {O}}(1)).} 1714: 1274: 270: 2385: 2380: 2105:
for an application of the Veronese embedding to the calculation of cohomology groups of smooth projective
849: 2375: 644: 1181: 2039: 949: 610: 565: 1901: 1638: 552: 516: 883: 2318:{\displaystyle {\frac {P(X_{0},\ldots ,X_{n})}{X_{0}^{\deg(P)}}}\mapsto P(1,X_{1},\ldots ,X_{n})} 455:. Its elements are therefore the rational functions with homogeneous numerator and some power of 401: 2171: 1660: 1488: 448: 502: 1334:, equivalently, their anticanonical line bundle is ample (in fact very ample). Their index ( 2139: 652: 596: 510: 232: 43: 8: 2166: 1167: 1163: 787: 779: 225: 118: 46: 2144: 1883: 726: 218: 54: 27: 23: 1330:
The negativity of the canonical line bundle makes projective spaces prime examples of
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is not contained in a hyperplane divisor, then the pull-back is an injection and the
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This last assertion is best summarized by the formula : for any relevant ideal
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This fact derives from a fundamental geometric statement on projective spaces: the
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Any choice of a finite system of nonsimultaneously vanishing global sections of a
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that does not contain all polynomials of a certain degree (referred to as an
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varies over the set of homogeneous polynomials, by setting the sections
2121:. The intersection theory of curves in the projective plane yields the 1171: 487: 1659:
projective transformations is likewise equivalent to the choice of a
2098: 1972:{\displaystyle j^{*}(\Gamma (\mathbf {P} ^{n},{\mathcal {O}}(1)))} 1399:, and, by a theorem of Kobayashi-Ochiai, projective spaces are 388:{\displaystyle \Gamma (D(P),{\mathcal {O}}_{\mathbb {P} (V)})} 187:{\displaystyle {\mathcal {I}}({\mathcal {V}}(I))={\sqrt {I}}.} 26:. This article aims to define the notion in terms of abstract 1469:
As affine spaces can be embedded in projective spaces, all
240: 717:, and the isomorphism is given by the degree of divisors. 466:φ. The restriction of the structure sheaf to the open set 208: 1264:{\displaystyle {\mathcal {K}}(\mathbb {P} _{k}^{n}),\,} 1037:{\displaystyle \Gamma (\mathbb {P} ,{\mathcal {O}}(m))} 459:
as the denominator, with same degree as the numerator.
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In particular, maximal homogeneous relevant ideals of
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and to describe some basic uses of projective spaces.
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In particular, the space of global sections 462:The situation is most clear at a non-vanishing 109:), the common zero locus of all polynomials in 2155: 2112: 2133: 2117:As Fano varieties, the projective spaces are 2073: 2052: 1131: 1110: 1098: 1077: 470:(φ) is then canonically identified with the 1711:defines a globally generated line bundle by 1059:=0 and of homogeneous polynomials of degree 267:is the projectivization of the vector space 1454:{\displaystyle \mathrm {Ind} (X)=\dim X+1.} 909:The space of local sections on an open set 607:and line bundles, the first twisting sheaf 310:The definition of the sheaf is done on the 1651:. The choice of a projective embedding of 1473:can be embedded in projective spaces too. 939:{\displaystyle U\subseteq \mathbb {P} (V)} 2016: 2001: 1503: 1364: 1260: 1239: 1157: 1008: 923: 888: 855: 825: 763: 745: 703: 521: 367: 276: 1403:amongst Fano varieties by the property 1992:The Veronese embeddings are embeddings 1704:{\displaystyle j:X\to \mathbf {P} ^{n}} 1616:{\displaystyle j:X\to \mathbf {P} ^{n}} 767:{\displaystyle \mathbb {P} _{k}^{n},\,} 2368: 1747:{\displaystyle j^{*}{\mathcal {O}}(1)} 1312:{\displaystyle {\mathcal {O}}(-(n+1))} 1051:< 0, and consists of constants in 640:is equivalent to hyperplane divisors. 300:{\displaystyle \mathbb {A} _{k}^{n+1}} 209:Construction of projectivized schemes 1626:the action of this group is in fact 1166:, which appears for instance as the 873:{\displaystyle \mathbb {P} _{k}^{n}} 1988:An example: the Veronese embeddings 979:is the space of homogeneous degree 643:Since the ring of polynomials is a 599:. All of these sheaves are in fact 13: 2088:{\textstyle N={\binom {n+d}{d}}-1} 2056: 1949: 1926: 1847: 1823: 1800: 1777: 1730: 1545: 1542: 1539: 1420: 1417: 1414: 1355: 1352: 1349: 1280: 1229: 1207:{\displaystyle {\mathcal {O}}(-1)} 1187: 1114: 1081: 1017: 1001: 955: 902:. The isomorphism is given by the 798: 673: 670: 667: 616: 571: 360: 336: 154: 144: 14: 2402: 1670:A morphism to a projective space 983:regular functions on the cone in 972:{\displaystyle {\mathcal {O}}(k)} 633:{\displaystyle {\mathcal {O}}(1)} 588:{\displaystyle {\mathcal {O}}(i)} 1979:is a linear system of dimension 1934: 1785: 1691: 1603: 1565: 1509: 721:Classification of vector bundles 688: 682: 603:. By the correspondence between 548:, that furthermore is complete. 1465:Morphisms to projective schemes 537:{\displaystyle \mathbb {P} (V)} 2312: 2274: 2268: 2261: 2255: 2235: 2203: 2184: 2011: 1966: 1963: 1960: 1954: 1929: 1923: 1861: 1858: 1852: 1826: 1817: 1814: 1811: 1805: 1780: 1774: 1741: 1735: 1686: 1598: 1569: 1561: 1430: 1424: 1374: 1359: 1306: 1303: 1291: 1285: 1254: 1234: 1201: 1192: 1031: 1028: 1022: 1004: 966: 960: 933: 927: 809: 803: 627: 621: 582: 576: 531: 525: 428: 418: 411: 405: 382: 377: 371: 351: 345: 339: 168: 165: 159: 149: 91:by the degree of polynomials. 1: 2331: 1880:If the range of the morphism 1152:Birkhoff-Grothendieck theorem 558:Divisors and twisting sheaves 34:Homogeneous polynomial ideals 895:{\displaystyle \mathbb {Z} } 314:of principal open sets  7: 2156:General projective geometry 2128: 2113:Curves in projective spaces 645:unique factorization domain 440:{\displaystyle (k_{P})_{0}} 10: 2407: 2134:General algebraic geometry 1902:linear system of divisors 1639:linear system of divisors 553:Glossary of scheme theory 2177: 22:plays a central role in 1067:. (Hence has dimension 2319: 2172:Homogeneous polynomial 2089: 2030: 1973: 1894: 1871: 1748: 1705: 1661:very ample line bundle 1617: 1576: 1524: 1455: 1393: 1313: 1265: 1208: 1158:Important line bundles 1141: 1038: 973: 940: 896: 874: 836: 768: 711: 634: 597:Serre twisting sheaves 589: 538: 441: 389: 301: 188: 2320: 2090: 2031: 1974: 1895: 1872: 1754:and a linear system 1749: 1706: 1618: 1577: 1525: 1456: 1394: 1314: 1266: 1209: 1142: 1039: 974: 941: 897: 875: 837: 769: 712: 635: 590: 539: 442: 390: 302: 189: 98:states that, for any 2391:Geometry of divisors 2194: 2140:Scheme (mathematics) 2040: 1996: 1910: 1884: 1761: 1715: 1674: 1586: 1534: 1498: 1410: 1345: 1275: 1224: 1182: 1071: 998: 950: 913: 884: 850: 793: 740: 663: 611: 566: 517: 511:algebraically closed 402: 333: 271: 139: 87:. It is a naturally 44:algebraically closed 2386:Algebraic varieties 2381:Projective geometry 2265: 2167:Projective geometry 2109:(smooth divisors). 1632:globally generating 1630:to the choice of a 1519: 1478:globally generated 1253: 1168:exceptional divisor 1164:tautological bundle 946:of the line bundle 869: 759: 698: 296: 2376:Algebraic geometry 2344:Algebraic Geometry 2315: 2239: 2145:Projective variety 2085: 2026: 1969: 1890: 1867: 1744: 1701: 1613: 1572: 1520: 1501: 1451: 1389: 1309: 1261: 1237: 1204: 1137: 1034: 969: 936: 892: 870: 853: 832: 764: 743: 727:invertible sheaves 707: 680: 630: 585: 534: 437: 385: 297: 274: 219:finite-dimensional 184: 55:finite-dimensional 28:algebraic geometry 24:algebraic geometry 2266: 2150:Proj construction 2071: 1893:{\displaystyle j} 1129: 1096: 904:first Chern class 880:is isomorphic to 817: 679: 505:. When the field 312:base of open sets 179: 100:homogeneous ideal 70:dual vector space 66:symmetric algebra 16:The concept of a 2398: 2362: 2339:Robin Hartshorne 2325: 2324: 2322: 2321: 2316: 2311: 2310: 2292: 2291: 2267: 2264: 2247: 2238: 2234: 2233: 2215: 2214: 2198: 2188: 2162:Projective space 2094: 2092: 2091: 2086: 2078: 2077: 2076: 2067: 2055: 2035: 2033: 2032: 2027: 2025: 2024: 2019: 2010: 2009: 2004: 1978: 1976: 1975: 1970: 1953: 1952: 1943: 1942: 1937: 1922: 1921: 1899: 1897: 1896: 1891: 1876: 1874: 1873: 1868: 1851: 1850: 1844: 1843: 1804: 1803: 1794: 1793: 1788: 1773: 1772: 1753: 1751: 1750: 1745: 1734: 1733: 1727: 1726: 1710: 1708: 1707: 1702: 1700: 1699: 1694: 1622: 1620: 1619: 1614: 1612: 1611: 1606: 1581: 1579: 1578: 1573: 1568: 1560: 1559: 1548: 1529: 1527: 1526: 1521: 1518: 1513: 1512: 1506: 1471:affine varieties 1460: 1458: 1457: 1452: 1423: 1398: 1396: 1395: 1390: 1373: 1372: 1367: 1358: 1318: 1316: 1315: 1310: 1284: 1283: 1270: 1268: 1267: 1262: 1252: 1247: 1242: 1233: 1232: 1216:canonical bundle 1213: 1211: 1210: 1205: 1191: 1190: 1146: 1144: 1143: 1138: 1136: 1135: 1134: 1125: 1113: 1103: 1102: 1101: 1092: 1080: 1043: 1041: 1040: 1035: 1021: 1020: 1011: 978: 976: 975: 970: 959: 958: 945: 943: 942: 937: 926: 901: 899: 898: 893: 891: 879: 877: 876: 871: 868: 863: 858: 841: 839: 838: 833: 828: 815: 802: 801: 773: 771: 770: 765: 758: 753: 748: 735:projective space 716: 714: 713: 708: 706: 697: 692: 691: 685: 677: 676: 639: 637: 636: 631: 620: 619: 605:Cartier divisors 594: 592: 591: 586: 575: 574: 546:abstract variety 543: 541: 540: 535: 524: 446: 444: 443: 438: 436: 435: 426: 425: 394: 392: 391: 386: 381: 380: 370: 364: 363: 306: 304: 303: 298: 295: 284: 279: 249:projectivization 193: 191: 190: 185: 180: 175: 158: 157: 148: 147: 107:irrelevant ideal 19:Projective space 2406: 2405: 2401: 2400: 2399: 2397: 2396: 2395: 2366: 2365: 2359: 2349:Springer-Verlag 2334: 2329: 2328: 2306: 2302: 2287: 2283: 2248: 2243: 2229: 2225: 2210: 2206: 2199: 2197: 2195: 2192: 2191: 2189: 2185: 2180: 2158: 2136: 2131: 2119:ruled varieties 2115: 2072: 2057: 2051: 2050: 2049: 2041: 2038: 2037: 2020: 2015: 2014: 2005: 2000: 1999: 1997: 1994: 1993: 1990: 1948: 1947: 1938: 1933: 1932: 1917: 1913: 1911: 1908: 1907: 1885: 1882: 1881: 1846: 1845: 1839: 1835: 1799: 1798: 1789: 1784: 1783: 1768: 1764: 1762: 1759: 1758: 1729: 1728: 1722: 1718: 1716: 1713: 1712: 1695: 1690: 1689: 1675: 1672: 1671: 1607: 1602: 1601: 1587: 1584: 1583: 1564: 1549: 1538: 1537: 1535: 1532: 1531: 1514: 1508: 1507: 1502: 1499: 1496: 1495: 1467: 1413: 1411: 1408: 1407: 1368: 1363: 1362: 1348: 1346: 1343: 1342: 1279: 1278: 1276: 1273: 1272: 1248: 1243: 1238: 1228: 1227: 1225: 1222: 1221: 1186: 1185: 1183: 1180: 1179: 1160: 1130: 1115: 1109: 1108: 1107: 1097: 1082: 1076: 1075: 1074: 1072: 1069: 1068: 1016: 1015: 1007: 999: 996: 995: 954: 953: 951: 948: 947: 922: 914: 911: 910: 887: 885: 882: 881: 864: 859: 854: 851: 848: 847: 824: 797: 796: 794: 791: 790: 754: 749: 744: 741: 738: 737: 723: 702: 693: 687: 686: 681: 666: 664: 661: 660: 615: 614: 612: 609: 608: 570: 569: 567: 564: 563: 560: 520: 518: 515: 514: 431: 427: 421: 417: 403: 400: 399: 398:to be the ring 366: 365: 359: 358: 357: 334: 331: 330: 285: 280: 275: 272: 269: 268: 211: 174: 153: 152: 143: 142: 140: 137: 136: 96:Nullstellensatz 94:The projective 83:and denoted by 77:polynomial ring 36: 12: 11: 5: 2404: 2394: 2393: 2388: 2383: 2378: 2364: 2363: 2357: 2333: 2330: 2327: 2326: 2314: 2309: 2305: 2301: 2298: 2295: 2290: 2286: 2282: 2279: 2276: 2273: 2270: 2263: 2260: 2257: 2254: 2251: 2246: 2242: 2237: 2232: 2228: 2224: 2221: 2218: 2213: 2209: 2205: 2202: 2182: 2181: 2179: 2176: 2175: 2174: 2169: 2164: 2157: 2154: 2153: 2152: 2147: 2142: 2135: 2132: 2130: 2127: 2123:Bézout theorem 2114: 2111: 2084: 2081: 2075: 2070: 2066: 2063: 2060: 2054: 2048: 2045: 2023: 2018: 2013: 2008: 2003: 1989: 1986: 1985: 1984: 1968: 1965: 1962: 1959: 1956: 1951: 1946: 1941: 1936: 1931: 1928: 1925: 1920: 1916: 1889: 1878: 1877: 1866: 1863: 1860: 1857: 1854: 1849: 1842: 1838: 1834: 1831: 1828: 1825: 1822: 1819: 1816: 1813: 1810: 1807: 1802: 1797: 1792: 1787: 1782: 1779: 1776: 1771: 1767: 1743: 1740: 1737: 1732: 1725: 1721: 1698: 1693: 1688: 1685: 1682: 1679: 1610: 1605: 1600: 1597: 1594: 1591: 1571: 1567: 1563: 1558: 1555: 1552: 1547: 1544: 1541: 1517: 1511: 1505: 1466: 1463: 1462: 1461: 1450: 1447: 1444: 1441: 1438: 1435: 1432: 1429: 1426: 1422: 1419: 1416: 1388: 1385: 1382: 1379: 1376: 1371: 1366: 1361: 1357: 1354: 1351: 1341:) is given by 1339:Fano varieties 1332:Fano varieties 1325:Euler sequence 1321: 1320: 1308: 1305: 1302: 1299: 1296: 1293: 1290: 1287: 1282: 1259: 1256: 1251: 1246: 1241: 1236: 1231: 1203: 1200: 1197: 1194: 1189: 1159: 1156: 1133: 1128: 1124: 1121: 1118: 1112: 1106: 1100: 1095: 1091: 1088: 1085: 1079: 1045: 1044: 1033: 1030: 1027: 1024: 1019: 1014: 1010: 1006: 1003: 987:associated to 968: 965: 962: 957: 935: 932: 929: 925: 921: 918: 890: 867: 862: 857: 831: 827: 823: 820: 814: 811: 808: 805: 800: 762: 757: 752: 747: 722: 719: 705: 701: 696: 690: 684: 675: 672: 669: 629: 626: 623: 618: 584: 581: 578: 573: 559: 556: 544:is in fact an 533: 530: 527: 523: 501:the scheme is 434: 430: 424: 420: 416: 413: 410: 407: 396: 395: 384: 379: 376: 373: 369: 362: 356: 353: 350: 347: 344: 341: 338: 294: 291: 288: 283: 278: 210: 207: 195: 194: 183: 178: 173: 170: 167: 164: 161: 156: 151: 146: 89:graded algebra 75:is called the 35: 32: 9: 6: 4: 3: 2: 2403: 2392: 2389: 2387: 2384: 2382: 2379: 2377: 2374: 2373: 2371: 2360: 2358:0-387-90244-9 2354: 2350: 2346: 2345: 2340: 2336: 2335: 2307: 2303: 2299: 2296: 2293: 2288: 2284: 2280: 2277: 2271: 2258: 2252: 2249: 2244: 2240: 2230: 2226: 2222: 2219: 2216: 2211: 2207: 2200: 2187: 2183: 2173: 2170: 2168: 2165: 2163: 2160: 2159: 2151: 2148: 2146: 2143: 2141: 2138: 2137: 2126: 2124: 2120: 2110: 2108: 2107:hypersurfaces 2104: 2100: 2095: 2082: 2079: 2068: 2064: 2061: 2058: 2046: 2043: 2021: 2006: 1982: 1957: 1944: 1939: 1918: 1914: 1906: 1905: 1904: 1903: 1887: 1864: 1855: 1840: 1836: 1832: 1829: 1820: 1808: 1795: 1790: 1769: 1765: 1757: 1756: 1755: 1738: 1723: 1719: 1696: 1683: 1680: 1677: 1668: 1666: 1662: 1658: 1654: 1650: 1646: 1645: 1640: 1637:-dimensional 1636: 1633: 1629: 1625: 1608: 1595: 1592: 1589: 1556: 1553: 1550: 1515: 1492: 1490: 1486: 1482: 1481: 1474: 1472: 1448: 1445: 1442: 1439: 1436: 1433: 1427: 1406: 1405: 1404: 1402: 1401:characterized 1386: 1383: 1380: 1377: 1369: 1340: 1337: 1333: 1328: 1326: 1300: 1297: 1294: 1288: 1257: 1249: 1244: 1220: 1219: 1218: 1217: 1198: 1195: 1178:is the sheaf 1177: 1173: 1169: 1165: 1155: 1153: 1148: 1126: 1122: 1119: 1116: 1104: 1093: 1089: 1086: 1083: 1066: 1062: 1058: 1054: 1050: 1025: 1012: 994: 993: 992: 990: 986: 982: 963: 930: 919: 916: 907: 905: 865: 860: 845: 829: 821: 818: 812: 806: 789: 786:the twisting 785: 781: 777: 760: 755: 750: 736: 732: 728: 718: 699: 694: 658: 654: 650: 646: 641: 624: 606: 602: 598: 579: 555: 554: 551: 547: 528: 512: 508: 504: 500: 495: 493: 489: 485: 481: 478:). Since the 477: 473: 472:affine scheme 469: 465: 460: 458: 454: 450: 432: 422: 414: 408: 374: 354: 348: 342: 329: 328: 327: 325: 321: 317: 313: 308: 292: 289: 286: 281: 266: 262: 260: 254: 250: 246: 242: 238: 234: 230: 227: 223: 220: 216: 206: 204: 200: 181: 176: 171: 162: 135: 134: 133: 131: 126: 124: 121:of the ideal 120: 116: 112: 108: 104: 101: 97: 92: 90: 86: 82: 78: 74: 71: 67: 63: 59: 56: 52: 48: 45: 41: 31: 29: 25: 21: 20: 2342: 2186: 2116: 2103:MathOverflow 2096: 1991: 1980: 1879: 1669: 1664: 1656: 1652: 1648: 1642: 1634: 1631: 1627: 1623: 1493: 1477: 1475: 1468: 1400: 1335: 1329: 1322: 1176:smooth point 1161: 1149: 1064: 1060: 1056: 1052: 1048: 1047:vanishes if 1046: 988: 984: 980: 908: 844:Picard group 783: 775: 731:line bundles 730: 724: 642: 601:line bundles 561: 549: 506: 498: 496: 491: 483: 479: 475: 467: 461: 456: 452: 449:localization 397: 323: 319: 315: 309: 264: 258: 256: 252: 248: 247:) is called 244: 236: 228: 222:vector space 214: 212: 202: 198: 196: 129: 127: 122: 114: 110: 102: 93: 84: 80: 72: 61: 58:vector space 50: 39: 37: 17: 15: 1644:line bundle 1480:line bundle 649:prime ideal 503:irreducible 464:linear form 257:projective 239:defined by 2370:Categories 2332:References 1628:equivalent 1489:very ample 1483:defines a 1172:blowing up 733:, on the 488:open cover 486:) form an 115:Nullstelle 2297:… 2269:↦ 2253:⁡ 2220:… 2080:− 2012:→ 1927:Γ 1919:∗ 1841:∗ 1824:Γ 1821:⊂ 1778:Γ 1770:∗ 1724:∗ 1687:→ 1599:→ 1440:⁡ 1289:− 1196:− 1002:Γ 920:⊆ 822:∈ 657:principal 337:Γ 322:), where 2341:(1977). 2129:See also 2097:See the 1485:morphism 1065:m > 0 1170:of the 842:so the 788:sheaves 784:exactly 224:over a 119:radical 68:of the 2355:  2099:answer 1657:modulo 1624:modulo 1214:. The 816:  782:, are 678:  653:height 647:, any 595:, the 261:-space 255:. The 233:scheme 231:. The 64:. The 49:, and 42:be an 2178:Notes 1641:on a 1174:of a 780:field 729:, or 655:1 is 474:spec( 235:over 226:field 217:be a 60:over 53:be a 47:field 2353:ISBN 2036:for 1162:The 1150:The 1063:for 1055:for 774:for 725:The 550:cf. 241:Proj 213:Let 113:(or 38:Let 2250:deg 2101:on 1663:on 1647:on 1437:dim 1336:cf. 1271:is 1147:). 846:of 651:of 509:is 490:of 451:at 263:on 251:of 132:, 79:on 2372:: 2351:. 2347:. 2125:. 1667:. 1655:, 1491:. 1449:1. 1327:. 906:. 778:a 513:, 499:ie 307:. 205:. 125:. 73:V* 2361:. 2313:) 2308:n 2304:X 2300:, 2294:, 2289:1 2285:X 2281:, 2278:1 2275:( 2272:P 2262:) 2259:P 2256:( 2245:0 2241:X 2236:) 2231:n 2227:X 2223:, 2217:, 2212:0 2208:X 2204:( 2201:P 2083:1 2074:) 2069:d 2065:d 2062:+ 2059:n 2053:( 2047:= 2044:N 2022:N 2017:P 2007:n 2002:P 1983:. 1981:n 1967:) 1964:) 1961:) 1958:1 1955:( 1950:O 1945:, 1940:n 1935:P 1930:( 1924:( 1915:j 1888:j 1865:. 1862:) 1859:) 1856:1 1853:( 1848:O 1837:j 1833:, 1830:X 1827:( 1818:) 1815:) 1812:) 1809:1 1806:( 1801:O 1796:, 1791:n 1786:P 1781:( 1775:( 1766:j 1742:) 1739:1 1736:( 1731:O 1720:j 1697:n 1692:P 1684:X 1681:: 1678:j 1665:X 1653:X 1649:X 1635:n 1609:n 1604:P 1596:X 1593:: 1590:j 1570:) 1566:k 1562:( 1557:1 1554:+ 1551:n 1546:L 1543:G 1540:P 1516:n 1510:k 1504:P 1446:+ 1443:X 1434:= 1431:) 1428:X 1425:( 1421:d 1418:n 1415:I 1387:1 1384:+ 1381:n 1378:= 1375:) 1370:n 1365:P 1360:( 1356:d 1353:n 1350:I 1319:. 1307:) 1304:) 1301:1 1298:+ 1295:n 1292:( 1286:( 1281:O 1258:, 1255:) 1250:n 1245:k 1240:P 1235:( 1230:K 1202:) 1199:1 1193:( 1188:O 1132:) 1127:n 1123:n 1120:+ 1117:m 1111:( 1105:= 1099:) 1094:m 1090:n 1087:+ 1084:m 1078:( 1061:m 1057:m 1053:k 1049:m 1032:) 1029:) 1026:m 1023:( 1018:O 1013:, 1009:P 1005:( 989:U 985:V 981:k 967:) 964:k 961:( 956:O 934:) 931:V 928:( 924:P 917:U 889:Z 866:n 861:k 856:P 830:, 826:Z 819:m 813:, 810:) 807:m 804:( 799:O 776:k 761:, 756:n 751:k 746:P 704:Z 700:= 695:n 689:k 683:P 674:c 671:i 668:P 628:) 625:1 622:( 617:O 583:) 580:i 577:( 572:O 532:) 529:V 526:( 522:P 507:k 492:X 484:φ 482:( 480:D 476:k 468:D 457:P 453:P 433:0 429:) 423:P 419:] 415:V 412:[ 409:k 406:( 383:) 378:) 375:V 372:( 368:P 361:O 355:, 352:) 349:P 346:( 343:D 340:( 324:P 320:P 318:( 316:D 293:1 290:+ 287:n 282:k 277:A 265:k 259:n 253:V 245:k 243:( 237:k 229:k 215:V 203:V 199:k 182:. 177:I 172:= 169:) 166:) 163:I 160:( 155:V 150:( 145:I 130:I 123:I 111:I 103:I 85:k 81:V 62:k 51:V 40:k

Index

Projective space
algebraic geometry
algebraic geometry
algebraically closed
field
finite-dimensional
vector space
symmetric algebra
dual vector space
polynomial ring
graded algebra
Nullstellensatz
homogeneous ideal
irrelevant ideal
radical
finite-dimensional
vector space
field
scheme
Proj
base of open sets
localization
linear form
affine scheme
open cover
irreducible
algebraically closed
abstract variety
Glossary of scheme theory
Serre twisting sheaves

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