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Morphism of algebraic varieties

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661:
is regular in the first sense if and only if it is so in the second sense. Also, it is not immediately clear whether regularity depends on a choice of affine charts (it does not.) This kind of a consistency issue, however, disappears if one adopts the formal definition. Formally, an (abstract)
2202:. Since morphisms of varieties are obtained by gluing morphisms of affine varieties in the same way morphisms of schemes are obtained by gluing morphisms of affine schemes, it follows that the category of varieties is a full subcategory of the category of schemes over 7416: 6141: 7566: 4851: 6635: 7044: 7669: 1196: 1859: 6911: 6765: 4013: 4235: 2034: 2557: 3821: 3465: 3113: 2671: 2094: 2189: 7188:. Then the issue here is whether the "regular-ness" can be patched together; this answer is yes and that can be seen from the construction of the structure sheaf of an affine variety as described at 5153: 2343: 5515: 4961: 252: 4641: 3694: 3358: 770: 7287: 3913: 6225: 6476: 5621: 892: 6962: 6043: 4306: 7092: 5662: 4533: 3548: 1302: 313: 2933: 5812: 5441: 5385: 3005: 2849: 7438: 4662: 1233: 2465: 6002: 1013: 169: 140: 6518: 5279: 5243: 1658: 1571: 1347: 4442: 2397: 205: 6802: 5859: 4137: 1955: 971: 7282: 7243: 5953: 5914: 5759: 5325: 5287:: The above does not say a morphism from a projective variety to a projective space is given by a single set of polynomials (unlike the affine case). For example, let 2730: 522: 2277: 1097: 435: 3247: 1260: 343: 817: 6974: 3298: 1718: 1631: 921: 542: 7571: 1104: 1432:
or more abstractly the ring of global sections of the structure sheaf) is a fundamental object in affine algebraic geometry. The only regular function on a
1785: 6807: 2470: 6643: 3707: 1437: 6246:" is a key in the proof, see Eisenbud, Ch. 14 of "Commutative algebra with a view toward algebraic geometry." In fact, the proof there shows that if 2562: 3934: 4149: 3566: 2282: 8043: 8015: 7907: 7879: 7209:
are quasi-projective, then the proof can be given. The non-quasi-projective case strongly depends on one's definition of an abstract variety
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of algebraic varieties. Because regular and biregular are very restrictive conditions – there are no non-constant regular functions on
7922: 6258: 3040: 7935: 7999: 7927: 7871: 6235: 4320:. Hence, the above construction determines a contravariant-equivalence between the category of algebraic varieties over a field 2042: 8073: 2115: 5051: 7979: 7861: 7125: 4479:, but the distinction is usually ignored in practice.) In particular, a regular map into the complex numbers is just a usual 3494: 2879: 5446: 4869: 4395: 213: 7411:{\displaystyle g\circ \phi ^{a}=g(\phi ({\overline {y_{1}}}),\dots ,\phi ({\overline {y_{m}}}))=\phi ({\overline {g}})=0} 4580: 8063: 4028: 6482: 699: 8068: 7944: 7156: 3826: 6164: 6409: 5524: 4394:), a rational function is regular if and only if it has no poles of codimension one. This is an algebraic analog of 830: 7889: 1900: 6916: 6136:{\displaystyle e(x)=\max\{\dim Z\mid Z{\text{ an irreducible component of }}f^{-1}(f(x)){\text{ containing }}x\}.} 6243: 4475:. (There is actually a slight technical difference: a regular map is a meromorphic map whose singular points are 4468: 4461: 1425: 7749: 5212: 1535: 4267: 7056: 5626: 4497: 7561:{\displaystyle {\phi ^{a}}^{\#}(g)=g(\phi ({\overline {y_{1}}}),\dots ,\phi ({\overline {y_{m}}}))=\phi (g)} 6513: 4846:{\displaystyle (a_{0}:\dots :a_{m})=(1:a_{1}/a_{0}:\dots :a_{m}/a_{0})\sim (a_{1}/a_{0},\dots ,a_{m}/a_{0})} 1265: 260: 7748:
Proof: it's enough to consider the case when the variety is affine and then use the fact that a Noetherian
7960:
The Red Book of Varieties and Schemes: Includes the Michigan Lectures (1974) on Curves and Their Jacobians
5770: 5390: 5334: 2954: 2735: 93:; a morphism between algebraic varieties is precisely a morphism of the underlying locally ringed spaces. 1204: 6630:{\displaystyle \operatorname {H} ^{p}(Y,R^{q}f_{*}f^{*}F)\Rightarrow \operatorname {H} ^{p+q}(X,f^{*}F)} 4476: 2417: 5960: 3606:) The image will either be a single point, or the whole projective line (this is a consequence of the 979: 524:
is the same as the restriction of a polynomial map whose components satisfy the defining equations of
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between the underlying topological spaces need not be an isomorphism (a counterexample is given by a
1636: 1549: 1307: 678: 90: 4414: 2348: 666:. When this definition is used, a morphism of varieties is just a morphism of locally ringed spaces. 178: 8025: 6777: 5829: 4085: 3577: 2221: 1873: 1865: 445: 39: 7050: 4324:
and dominant rational maps between them and the category of finitely generated field extension of
1927: 926: 7136: 4539: 4409: 1661: 1433: 671: 67: 35: 7796: 7260: 7221: 5919: 5880: 5725: 8039: 8011: 7975: 7931: 7903: 7875: 7146: 6373: 5294: 2703: 1906:, then, working with only the closed points, the above coincides with the definition given at 1468: 495: 83: 2249: 8003: 7989: 7967: 7917: 6501: 6385: 6344: 6312: 6254:, then the dimension equality in 2. of the theorem holds in general (not just generically). 6239: 4992:
is a fraction of homogeneous elements of the same degree in the homogeneous coordinate ring
3931:
The image of a morphism of varieties need not be open nor closed (for example, the image of
2195: 1441: 1021: 560: 359: 172: 79: 7993: 7039:{\displaystyle \operatorname {deg} (f^{*}L)=\operatorname {deg} (f)\operatorname {deg} (L)} 3118: 1238: 321: 8035: 7963: 7899: 7141: 6281: 5000:. We can arrange the fractions so that they all have the same homogeneous denominator say 4472: 3595: 3580: 1896: 1872:. All morphisms between affine schemes are of this type and gluing such morphisms gives a 1429: 1421: 346: 28: 7664:{\displaystyle f^{\#a}=({\overline {y_{1}}}\circ f,\dots ,{\overline {y_{m}}}\circ f)=f.} 778: 1191:{\displaystyle \phi ^{a}=(\phi ({\overline {y_{1}}}),\dots ,\phi ({\overline {y_{m}}}))} 7189: 6389: 4453: 4391: 4387: 3925: 3252: 1687: 1600: 897: 527: 208: 8057: 7955: 6251: 4405: 4253: 4249: 2097: 1854:{\displaystyle \phi ^{a}:X\to Y,\,{\mathfrak {p}}\mapsto \phi ^{-1}({\mathfrak {p}})} 1765: 670:
The composition of regular maps is again regular; thus, algebraic varieties form the
6906:{\displaystyle R^{q}f_{*}(f^{*}F)=R^{q}f_{*}{\mathcal {O}}_{X}\otimes L^{\otimes n}} 5694:
be a dominating (i.e., having dense image) morphism of algebraic varieties, and let
1740:. This characterization is sometimes taken as the definition of a regular function. 6760:{\displaystyle \chi (f^{*}F)=\sum _{q=0}^{\infty }(-1)^{q}\chi (R^{q}f_{*}f^{*}F).} 4309: 4241: 4024: 663: 110: 71: 2943:. It is regular at (0, 1) despite the expression since, as a rational function on 677:
Regular maps between affine varieties correspond contravariantly in one-to-one to
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This fact means that the category of affine varieties can be identified with a
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Here is the argument showing the definitions coincide. Clearly, we can assume
4566:= 0 for simplicity. Then, by continuity, there is an open affine neighborhood 3483:
given by σ(x : y) = (y : x); in particular, σ exchanges 0 and ∞. If
75: 43: 1538:; i.e., an open subvariety of a projective variety, then the function field 693:
is a morphism of affine varieties, then it defines the algebra homomorphism
4655:
are the homogeneous coordinates. Note the target space is the affine space
4008:{\displaystyle \mathbf {A} ^{2}\to \mathbf {A} ^{2},\,(x,y)\mapsto (x,xy)} 2210: 4230:{\displaystyle k(Y)=\varinjlim k\hookrightarrow k(X),\,g\mapsto g\circ f} 7752:
is the intersection of all the localizations at height-one prime ideals.
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is bijective. But the corresponding ring homomorphism is the inclusion
2029:{\displaystyle {\mathfrak {m}}_{f(x)}=\phi ^{-1}({\mathfrak {m}}_{x})} 3025:
is an algebraic variety since it is an open subset of a variety. If
2552:{\displaystyle f:\mathbf {A} ^{1}\to X,\,t\mapsto (t^{2}-1,t^{3}-t)} 641:
It is not immediately obvious that the two definitions coincide: if
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for a ramified covering shows the "étale" here cannot be omitted.)
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is the degree of the finite field extension of the function field
3816:{\displaystyle p^{\#}:k\to k=k\otimes _{k}k,\,f\mapsto f\otimes 1} 662:
algebraic variety is defined to be a particular kind of a locally
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with respect to Zariski topologies on the source and the target.
3460:{\displaystyle \mathbf {P} ^{1}=\mathbf {A} ^{1}\cup \{\infty \}} 3384:
is in fact a polynomial. Hence, the ring of regular functions on
5195:, then, by the above procedure, one can pick a different set of 3108:{\displaystyle D_{\mathbf {A} ^{2}}(x)=\mathbf {A} ^{2}-\{x=0\}} 7962:. Lecture Notes in Mathematics. Vol. 1358 (2nd ed.). 27:"Biregular" redirects here. For the graph theory concept, see 6284:
surjective morphism between algebraic varieties over a field
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is a function between the varieties that is given locally by
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is neither open nor closed). However, one can still say: if
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in the function field may all be realised as morphisms from
2666:{\displaystyle f^{\#}:k\to k,\,g\mapsto g(t^{2}-1,t^{3}-t),} 1436:
is constant (this can be viewed as an algebraic analogue of
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and, conversely, such a morphism as a rational function on
2089:{\displaystyle {\mathfrak {m}}_{x},{\mathfrak {m}}_{f(x)}} 7683:
be the coordinate ring of such an affine neighborhood of
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In Mumford's red book, the theorem is proved by means of
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simultaneously. If they vanish simultaneously at a point
2184:{\displaystyle {\mathfrak {m}}_{x}=\{g\in k\mid g(x)=0\}} 973:
is an algebra homomorphism, then it induces the morphism
5148:{\displaystyle f(x)=(f_{0}(x):f_{1}(x):\dots :f_{m}(x))} 3704:
are affine, then the corresponding ring homomorphism is
2338:{\displaystyle f:X\to \mathbf {A} ^{1},\,(x,y)\mapsto x} 58:. A regular map whose inverse is also regular is called 2559:
is a morphism. It corresponds to the ring homomorphism
4143:
induces an injection on the level of function fields:
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of the same degree in the homogeneous coordinate ring
89:
An algebraic variety has naturally the structure of a
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simultaneously (see Note at the end of the section.)
5054: 4872: 4665: 4583: 4500: 4417: 4398:. There is also a relative version of this fact; see 4367:
is a smooth complete curve, any rational function on
4270: 4248:. (More abstractly, this is the induced map from the 4152: 4088: 3937: 3829: 3710: 3639: 3497: 3417: 3306: 3255: 3121: 3043: 2957: 2882: 2851:, which is not an isomorphism and so the restriction 2738: 2706: 2565: 2473: 2420: 2351: 2285: 2252: 2118: 2045: 1966: 1930: 1788: 1690: 1639: 1603: 1552: 1353:
is an isomorphism of affine varieties if and only if
1310: 1268: 1241: 1207: 1107: 1024: 982: 929: 900: 833: 781: 702: 530: 498: 362: 324: 263: 216: 181: 148: 119: 5510:{\displaystyle \{(x:y:z)\in X\mid x\neq 0,z\neq 0\}} 5045:. Hence, going back to the homogeneous coordinates, 4956:{\displaystyle f|_{U}(x)=(g_{1}(x),\dots ,g_{m}(x))} 3479:
and ∞ = (1 : 0). There is an automorphism σ of
247:{\displaystyle \mathbb {A} ^{n}\to \mathbb {A} ^{m}} 7109:is algebraically closed, then each geometric fiber 6968:is positive, comparing the leading terms, one has: 4636:{\displaystyle f:U\to \mathbf {P} ^{m}-\{y_{0}=0\}} 4019:is a morphism between varieties, then the image of 1676:if and only if there are some homogeneous elements 7663: 7560: 7410: 7276: 7237: 7086: 7038: 6956: 6905: 6796: 6759: 6629: 6470: 6219: 6135: 5996: 5947: 5908: 5853: 5806: 5753: 5656: 5615: 5509: 5435: 5379: 5319: 5273: 5237: 5147: 4955: 4845: 4635: 4527: 4436: 4300: 4229: 4131: 4007: 3907: 3815: 3688: 3542: 3459: 3352: 3292: 3241: 3107: 2999: 2927: 2843: 2724: 2665: 2551: 2459: 2391: 2337: 2271: 2183: 2088: 2028: 1949: 1853: 1712: 1652: 1625: 1565: 1341: 1296: 1254: 1227: 1190: 1091: 1007: 965: 915: 886: 811: 764: 614:is regular as a function on some affine charts of 536: 516: 429: 337: 307: 246: 199: 163: 134: 6323:such that the restriction of the structure sheaf 4404:A morphism between algebraic varieties that is a 3689:{\displaystyle p:X\times Y\to X,\,(x,y)\mapsto x} 3353:{\displaystyle f={g \over x^{n}}={h \over y^{m}}} 765:{\displaystyle f^{\#}:k\to k,\,g\mapsto g\circ f} 6062: 5211:In fact, the above description is valid for any 4448:is bijective birational and the target space of 3908:{\displaystyle (f\otimes 1)(x,y)=f(p(x,y))=f(x)} 2345:is a morphism; it is bijective with the inverse 488:, and hence satisfies the defining equations of 6220:{\displaystyle X_{n}=\{x\in X\mid e(x)\geq n\}} 6029:be a morphism of algebraic varieties. For each 7201:It is not clear how to prove this, though. If 6471:{\displaystyle \chi (f^{*}F)=\deg(f)\chi (F).} 5616:{\displaystyle (x:y)=(xy:y^{2})=(xy:xz)=(y:z)} 4244:runs over all nonempty open affine subsets of 4062:, then there is a nonempty open affine subset 3614:is actually constant, we have to attribute to 3400:is determined by its coordinate ring and thus 887:{\displaystyle g\circ f=g(f_{1},\dots ,f_{m})} 50:. A morphism from an algebraic variety to the 5254:'s are in the homogeneous coordinate ring of 5218:, an open subvariety of a projective variety 1899:that are finitely generated algebras over an 8: 6957:{\displaystyle R^{q}f_{*}{\mathcal {O}}_{X}} 6214: 6181: 6127: 6065: 5861:and (b) for every irreducible closed subset 5504: 5450: 4630: 4611: 3454: 3448: 3102: 3090: 2178: 2136: 1364:is a closed subvariety of an affine variety 7771: 6365:is then also the rank of this free module. 6011: 5676: 1507:. Caution: the condition is for some pair ( 1376:is the restriction of regular functions on 1357:is an isomorphism of the coordinate rings. 7820: 7808: 7783: 7568:since φ is an algebra homomorphism. Also, 674:where the morphisms are the regular maps. 7632: 7626: 7600: 7594: 7579: 7573: 7526: 7520: 7491: 7485: 7455: 7448: 7443: 7440: 7389: 7363: 7357: 7328: 7322: 7301: 7289: 7268: 7262: 7229: 7223: 7078: 7072: 7071: 7064: 7058: 6991: 6976: 6948: 6942: 6941: 6934: 6924: 6918: 6894: 6881: 6875: 6874: 6867: 6857: 6838: 6825: 6815: 6809: 6785: 6779: 6742: 6732: 6722: 6706: 6687: 6676: 6657: 6645: 6615: 6587: 6568: 6558: 6548: 6526: 6520: 6423: 6411: 6172: 6166: 6119: 6092: 6083: 6045: 5962: 5927: 5921: 5888: 5882: 5831: 5772: 5733: 5727: 5648: 5643: 5628: 5562: 5526: 5448: 5392: 5336: 5302: 5296: 5261: 5259: 5225: 5223: 5127: 5099: 5077: 5053: 4935: 4907: 4882: 4877: 4871: 4834: 4825: 4819: 4800: 4791: 4785: 4766: 4757: 4751: 4732: 4723: 4717: 4692: 4673: 4664: 4618: 4602: 4597: 4582: 4519: 4514: 4499: 4428: 4416: 4335:is a smooth complete curve (for example, 4269: 4264:.) Conversely, every inclusion of fields 4211: 4168: 4151: 4093: 4087: 3968: 3959: 3954: 3944: 3939: 3936: 3828: 3797: 3776: 3715: 3709: 3664: 3638: 3529: 3502: 3496: 3439: 3434: 3424: 3419: 3416: 3342: 3333: 3322: 3313: 3305: 3278: 3254: 3221: 3190: 3174: 3169: 3139: 3134: 3132: 3120: 3081: 3076: 3055: 3050: 3048: 3042: 2979: 2956: 2904: 2881: 2829: 2783: 2764: 2737: 2705: 2645: 2626: 2609: 2570: 2564: 2534: 2515: 2501: 2486: 2481: 2472: 2451: 2438: 2425: 2419: 2380: 2350: 2313: 2304: 2299: 2284: 2263: 2251: 2127: 2121: 2120: 2117: 2071: 2065: 2064: 2054: 2048: 2047: 2044: 2017: 2011: 2010: 1997: 1975: 1969: 1968: 1965: 1941: 1929: 1842: 1841: 1829: 1816: 1815: 1814: 1793: 1787: 1697: 1689: 1640: 1638: 1610: 1602: 1553: 1551: 1324: 1317: 1312: 1309: 1282: 1275: 1270: 1267: 1246: 1240: 1219: 1209: 1206: 1171: 1165: 1136: 1130: 1112: 1106: 1078: 1069: 1050: 1023: 987: 981: 928: 899: 875: 856: 832: 780: 746: 707: 701: 529: 497: 416: 407: 388: 361: 329: 323: 296: 277: 262: 238: 234: 233: 223: 219: 218: 215: 180: 155: 151: 150: 147: 126: 122: 121: 118: 4301:{\displaystyle k(Y)\hookrightarrow k(X)} 1463:if, in some open affine neighborhood of 78:maps are widely used as well; they are 7832: 7764: 7173: 7087:{\displaystyle f_{*}{\mathcal {O}}_{X}} 6085: an irreducible component of  5657:{\displaystyle f:X\to \mathbf {P} ^{1}} 4853:. Thus, by definition, the restriction 4528:{\displaystyle f:X\to \mathbf {P} ^{m}} 2235:variables and the regular functions on 7844: 6238:. For an algebraic approach where the 3543:{\displaystyle \sigma ^{\#}(f)=f(1/z)} 2680:Continuing the preceding example, let 1424:studied in differential geometry. The 1297:{\displaystyle {\phi ^{a}}^{\#}=\phi } 308:{\displaystyle f=(f_{1},\dots ,f_{m})} 6315:, there is some nonempty open subset 6288:. Then, by definition, the degree of 6242:plays a main role and the notion of " 4139:is injective. Thus, the dominant map 4046:of algebraic varieties is said to be 2928:{\displaystyle f(x,y)={1-y \over x}.} 2673:which is seen to be injective (since 1744:Comparison with a morphism of schemes 1546:) is the same as that of the closure 7: 6492:is a finite surjective morphism, if 5818:There exists a nonempty open subset 5807:{\displaystyle \dim Z\geq \dim W+r.} 5710:For every irreducible closed subset 5436:{\displaystyle (x:y:z)\mapsto (y:z)} 5380:{\displaystyle (x:y:z)\mapsto (x:y)} 4058:is a nonempty open affine subset of 3608:completeness of projective varieties 3000:{\displaystyle f(x,y)={x \over 1+y}} 2844:{\displaystyle k=k\hookrightarrow k} 2692:is the complement of the hyperplane 1662:Projective variety#Variety structure 1475:; i.e., there are regular functions 630:, if it is regular at all points of 4050:if it has dense image. For such an 3396:cannot be affine since if it were, 2222:Morphism of schemes § Examples 2122: 2066: 2049: 2012: 1970: 1843: 1817: 1228:{\displaystyle {\overline {y}}_{i}} 7895:Algebraic Geometry, A First Course 7580: 7456: 6688: 6584: 6523: 4094: 3716: 3503: 3451: 2571: 1942: 1318: 1283: 708: 25: 8031:The Arithmetic of Elliptic Curves 7797:Foundations of algebraic geometry 2460:{\displaystyle y^{2}=x^{3}+x^{2}} 681:between the coordinate rings: if 649:are affine varieties, then a map 62:, and the biregular maps are the 5997:{\displaystyle \dim Z=\dim W+r.} 5873:and every irreducible component 5718:and every irreducible component 5644: 4598: 4515: 3955: 3940: 3924:A morphism between varieties is 3435: 3420: 3170: 3135: 3077: 3051: 2482: 2300: 1577:and thus a rational function on 1008:{\displaystyle \phi ^{a}:X\to Y} 164:{\displaystyle \mathbb {A} ^{m}} 135:{\displaystyle \mathbb {A} ^{n}} 6259:Zariski's connectedness theorem 5274:{\displaystyle {\overline {X}}} 5238:{\displaystyle {\overline {X}}} 4487:Morphisms to a projective space 3696:is a morphism of varieties. If 3603: 3554:is regular at ∞ if and only if 2407:is an isomorphism of varieties. 2231:are exactly the polynomials in 1907: 1653:{\displaystyle {\overline {X}}} 1566:{\displaystyle {\overline {X}}} 1420:, and are algebraic analogs of 1342:{\displaystyle {f^{\#}}^{a}=f.} 894:is a polynomial in elements of 672:category of algebraic varieties 254:. Explicitly, it has the form: 7649: 7591: 7555: 7549: 7540: 7537: 7517: 7502: 7482: 7476: 7467: 7461: 7399: 7386: 7377: 7374: 7354: 7339: 7319: 7313: 7284:is a map to the affine space, 7190:affine variety#Structure sheaf 7126:Degree of a continuous mapping 7033: 7027: 7018: 7012: 7000: 6984: 6847: 6831: 6751: 6715: 6703: 6693: 6666: 6650: 6624: 6602: 6580: 6577: 6535: 6462: 6456: 6450: 6444: 6432: 6416: 6205: 6199: 6116: 6113: 6107: 6101: 6056: 6050: 5942: 5936: 5903: 5897: 5848: 5842: 5748: 5742: 5639: 5610: 5598: 5592: 5574: 5568: 5546: 5540: 5528: 5471: 5453: 5430: 5418: 5415: 5412: 5394: 5374: 5362: 5359: 5356: 5338: 5142: 5139: 5133: 5111: 5105: 5089: 5083: 5070: 5064: 5058: 5032:for some homogeneous elements 4950: 4947: 4941: 4919: 4913: 4900: 4894: 4888: 4878: 4840: 4778: 4772: 4704: 4698: 4666: 4593: 4554:-th homogeneous coordinate of 4510: 4437:{\displaystyle t\mapsto t^{p}} 4421: 4295: 4289: 4283: 4280: 4274: 4215: 4205: 4199: 4193: 4190: 4184: 4162: 4156: 4126: 4120: 4114: 4111: 4105: 4002: 3987: 3984: 3981: 3969: 3950: 3902: 3896: 3887: 3884: 3872: 3866: 3857: 3845: 3842: 3830: 3801: 3791: 3785: 3769: 3763: 3754: 3742: 3736: 3733: 3727: 3680: 3677: 3665: 3655: 3618:the value ∞ at some points of 3537: 3523: 3514: 3508: 3287: 3259: 3236: 3208: 3199: 3183: 3180: 3165: 3156: 3153: 3147: 3125: 3069: 3063: 2973: 2961: 2898: 2886: 2838: 2826: 2813: 2804: 2798: 2795: 2757: 2748: 2742: 2716: 2657: 2619: 2613: 2603: 2597: 2591: 2588: 2582: 2546: 2508: 2505: 2492: 2392:{\displaystyle g(x)=(x,x^{2})} 2386: 2367: 2361: 2355: 2329: 2326: 2314: 2295: 2169: 2163: 2154: 2148: 2081: 2075: 2023: 2006: 1985: 1979: 1848: 1838: 1822: 1805: 1768:, then each ring homomorphism 1707: 1694: 1620: 1607: 1589:for some homogeneous elements 1185: 1182: 1162: 1147: 1127: 1121: 1075: 1043: 1034: 1028: 999: 960: 954: 948: 945: 939: 910: 904: 881: 849: 806: 800: 791: 785: 750: 740: 734: 728: 725: 719: 508: 413: 381: 372: 366: 302: 270: 229: 200:{\displaystyle f\colon X\to Y} 191: 1: 6797:{\displaystyle L^{\otimes n}} 6236:Noether's normalization lemma 5854:{\displaystyle U\subset f(X)} 4483:(complex-analytic function). 4132:{\displaystyle f^{\#}:k\to k} 1524: 1385: 7835:, Ch. I, § 8. Theorems 2, 3. 7638: 7606: 7532: 7497: 7394: 7369: 7334: 7149:– The algebraic analogue of 6964:has positive codimension if 5623:) and so defines a morphism 5266: 5245:; the difference being that 5230: 4975:'s are regular functions on 4371:may be viewed as a morphism 3625:For any algebraic varieties 2100:corresponding to the points 1950:{\displaystyle \phi =f^{\#}} 1924:is a morphism, then writing 1887:are affine varieties; i.e., 1702: 1664:.) Then a rational function 1645: 1615: 1558: 1396:In the particular case that 1214: 1177: 1142: 966:{\displaystyle \phi :k\to k} 819:are the coordinate rings of 602:and the restricted function 570:if there is a neighbourhood 460:define the same function on 82:that are defined locally by 7157:Resolution of singularities 6264:Degree of a finite morphism 4659:through the identification 4542:to a projective space. Let 4469:complex algebraic varieties 3471: : 1) with the points 3467:by identifying the points ( 2700:is affine. The restriction 827:; it is well-defined since 8090: 7995:Basic Algebraic Geometry 1 7823:, Ch. I, Proposition 6.8.. 7257:, then, a priori thinking 7123: 7117:) consists exactly of deg( 6256: 5166:and by continuity for all 4396:Hartogs' extension theorem 3487:is a rational function on 2939:is a rational function on 2239:are exactly the constants. 2219: 1901:algebraically closed field 26: 8008:10.1007/978-3-642-37956-7 7731:is a regular function on 7277:{\displaystyle \phi ^{a}} 7238:{\displaystyle \phi ^{a}} 6913:and since the support of 6244:universally catenary ring 6154:; i.e., for each integer 5948:{\displaystyle f^{-1}(U)} 5909:{\displaystyle f^{-1}(W)} 5754:{\displaystyle f^{-1}(W)} 5443:agree on the open subset 5204:'s that do not vanish at 4444:.) On the other hand, if 4308:is induced by a dominant 3029:is a regular function on 2227:The regular functions on 1426:ring of regular functions 1388:below for more examples. 492:. That is, a regular map 7750:integrally closed domain 5320:{\displaystyle y^{2}=xz} 5213:quasi-projective variety 3392:. (This also shows that 2725:{\displaystyle f:U\to X} 2688: − {1}. Since 1536:quasi-projective variety 517:{\displaystyle f:X\to Y} 207:is the restriction of a 86:instead of polynomials. 6804:of a line bundle, then 6514:Leray spectral sequence 6483:Riemann–Hurwitz formula 5672:The important fact is: 4343:is a rational map from 2951:can also be written as 2272:{\displaystyle y=x^{2}} 2198:of affine schemes over 1372:is the inclusion, then 452:(note: two polynomials 8074:Functions and mappings 7951:, old version v. 5.xx. 7811:, Ch. I, Theorem 4.4.. 7665: 7562: 7412: 7278: 7239: 7088: 7040: 6958: 6907: 6798: 6761: 6692: 6631: 6472: 6221: 6137: 6121: containing  5998: 5949: 5910: 5855: 5808: 5755: 5658: 5617: 5511: 5437: 5381: 5321: 5275: 5239: 5149: 4957: 4847: 4637: 4529: 4467:A regular map between 4462:Zariski's main theorem 4438: 4363:. In particular, when 4347:to a projective space 4302: 4231: 4133: 4009: 3909: 3817: 3690: 3544: 3461: 3354: 3300:. Thus, we can write: 3294: 3249:. Similarly, it is in 3243: 3109: 3001: 2929: 2861:is not an isomorphism. 2845: 2726: 2667: 2553: 2461: 2393: 2339: 2273: 2209:For more details, see 2191:. This is immediate.) 2185: 2090: 2030: 1951: 1855: 1779:determines a morphism 1714: 1684:of the same degree in 1672:is regular at a point 1654: 1627: 1567: 1459:is regular at a point 1343: 1298: 1256: 1229: 1192: 1093: 1092:{\displaystyle k=k/J,} 1009: 967: 917: 888: 813: 766: 547:More generally, a map 538: 518: 431: 430:{\displaystyle k=k/I,} 339: 309: 248: 201: 175:), then a regular map 165: 136: 46:. It is also called a 7666: 7563: 7413: 7279: 7240: 7151:local diffeomorphisms 7089: 7041: 6959: 6908: 6799: 6762: 6672: 6632: 6473: 6222: 6138: 5999: 5950: 5911: 5856: 5809: 5756: 5659: 5618: 5512: 5438: 5382: 5322: 5276: 5240: 5150: 4958: 4848: 4646:is a morphism, where 4638: 4538:be a morphism from a 4530: 4439: 4303: 4232: 4134: 4010: 3910: 3818: 3691: 3562:) is regular at zero. 3545: 3462: 3355: 3295: 3244: 3242:{\displaystyle k=k=k} 3110: 3002: 2930: 2846: 2727: 2668: 2554: 2462: 2394: 2340: 2274: 2186: 2091: 2031: 1952: 1856: 1715: 1655: 1628: 1568: 1515:) not for all pairs ( 1344: 1299: 1257: 1255:{\displaystyle y_{i}} 1230: 1193: 1094: 1010: 968: 918: 889: 814: 767: 679:algebra homomorphisms 539: 519: 432: 340: 338:{\displaystyle f_{i}} 310: 249: 202: 166: 137: 38:, a morphism between 8026:Silverman, Joseph H. 7990:Shafarevich, Igor R. 7799:, Proposition 6.5.7. 7572: 7439: 7288: 7261: 7222: 7162:contraction morphism 7057: 6975: 6917: 6808: 6778: 6644: 6519: 6508:a coherent sheaf on 6410: 6401:Euler characteristic 6399:, writing χ for the 6165: 6152:upper-semicontinuous 6044: 5961: 5920: 5881: 5830: 5771: 5726: 5668:Fibers of a morphism 5627: 5525: 5447: 5391: 5335: 5295: 5258: 5222: 5183:'s do not vanish at 5052: 5007:. Then we can write 4983:is projective, each 4870: 4663: 4581: 4498: 4481:holomorphic function 4415: 4268: 4150: 4086: 4027:of its closure (cf. 3935: 3827: 3708: 3637: 3495: 3415: 3304: 3253: 3119: 3041: 2955: 2880: 2868:be the affine curve 2736: 2704: 2563: 2471: 2418: 2414:be the affine curve 2403:is also a morphism, 2349: 2283: 2250: 2246:be the affine curve 2116: 2043: 1964: 1928: 1786: 1688: 1637: 1601: 1550: 1308: 1266: 1239: 1205: 1105: 1022: 980: 927: 898: 831: 779: 700: 578:and a neighbourhood 528: 496: 360: 322: 261: 214: 179: 146: 117: 91:locally ringed space 68:projective varieties 8064:Algebraic varieties 7867:Intersection Theory 7774:, p. 25, Def.. 7253:is a polynomial in 6015: —  5680: —  4562:) is nonzero; say, 4460:is biregular. (cf. 3610:). That is, unless 3372:. But this implies 3368:are polynomials in 1874:morphism of schemes 1736:does not vanish at 1503:does not vanish at 1471:that is regular at 1438:Liouville's theorem 812:{\displaystyle k,k} 40:algebraic varieties 8069:Types of functions 7949:Algebraic geometry 7923:Algebraic Geometry 7847:, Example 18.3.9.. 7661: 7558: 7408: 7274: 7235: 7137:Algebraic function 7084: 7036: 6954: 6903: 6794: 6774:is a tensor power 6770:In particular, if 6757: 6627: 6468: 6217: 6133: 6013: 5994: 5945: 5906: 5851: 5804: 5751: 5678: 5654: 5613: 5507: 5433: 5377: 5317: 5271: 5235: 5145: 4953: 4843: 4633: 4540:projective variety 4525: 4434: 4410:Frobenius morphism 4390:(in particular, a 4298: 4227: 4176: 4129: 4005: 3905: 3813: 3686: 3540: 3457: 3350: 3290: 3239: 3105: 2997: 2925: 2841: 2722: 2663: 2549: 2457: 2389: 2335: 2269: 2181: 2086: 2026: 1957:, we need to show 1947: 1851: 1710: 1650: 1623: 1563: 1447:A scalar function 1434:projective variety 1339: 1294: 1252: 1235:are the images of 1225: 1188: 1089: 1018:given by: writing 1005: 963: 913: 884: 809: 762: 565:regular at a point 534: 514: 427: 335: 305: 244: 197: 161: 132: 84:rational fractions 70:– the concepts of 36:algebraic geometry 8045:978-0-387-09494-6 8017:978-0-387-97716-4 7918:Hartshorne, Robin 7909:978-1-4757-2189-8 7881:978-0-387-98549-7 7707:and some nonzero 7641: 7609: 7535: 7500: 7397: 7372: 7337: 7094:is the degree of 6122: 6086: 5702: − dim 5269: 5233: 4355:is a regular map 4169: 4029:constructible set 4023:contains an open 3633:, the projection 3348: 3328: 3293:{\displaystyle k} 2995: 2920: 1713:{\displaystyle k} 1705: 1648: 1626:{\displaystyle k} 1618: 1561: 1469:rational function 1418:regular functions 1404:the regular maps 1392:Regular functions 1217: 1180: 1145: 923:. Conversely, if 916:{\displaystyle k} 537:{\displaystyle Y} 80:partial functions 54:is also called a 18:Dominant morphism 16:(Redirected from 8081: 8049: 8034:(2nd ed.). 8021: 8000:Springer Science 7985: 7941: 7913: 7885: 7872:Springer Science 7848: 7842: 7836: 7830: 7824: 7818: 7812: 7806: 7800: 7793: 7787: 7781: 7775: 7772:Shafarevich 2013 7769: 7753: 7746: 7740: 7677: 7671: 7670: 7668: 7667: 7662: 7642: 7637: 7636: 7627: 7610: 7605: 7604: 7595: 7587: 7586: 7567: 7565: 7564: 7559: 7536: 7531: 7530: 7521: 7501: 7496: 7495: 7486: 7460: 7459: 7454: 7453: 7452: 7433: 7427: 7417: 7415: 7414: 7409: 7398: 7390: 7373: 7368: 7367: 7358: 7338: 7333: 7332: 7323: 7306: 7305: 7283: 7281: 7280: 7275: 7273: 7272: 7244: 7242: 7241: 7236: 7234: 7233: 7216: 7210: 7199: 7193: 7178: 7093: 7091: 7090: 7085: 7083: 7082: 7077: 7076: 7069: 7068: 7045: 7043: 7042: 7037: 6996: 6995: 6963: 6961: 6960: 6955: 6953: 6952: 6947: 6946: 6939: 6938: 6929: 6928: 6912: 6910: 6909: 6904: 6902: 6901: 6886: 6885: 6880: 6879: 6872: 6871: 6862: 6861: 6843: 6842: 6830: 6829: 6820: 6819: 6803: 6801: 6800: 6795: 6793: 6792: 6766: 6764: 6763: 6758: 6747: 6746: 6737: 6736: 6727: 6726: 6711: 6710: 6691: 6686: 6662: 6661: 6636: 6634: 6633: 6628: 6620: 6619: 6598: 6597: 6573: 6572: 6563: 6562: 6553: 6552: 6531: 6530: 6512:, then from the 6477: 6475: 6474: 6469: 6428: 6427: 6361:. The degree of 6342: 6313:generic freeness 6240:generic freeness 6226: 6224: 6223: 6218: 6177: 6176: 6142: 6140: 6139: 6134: 6123: 6120: 6100: 6099: 6087: 6084: 6016: 6003: 6001: 6000: 5995: 5954: 5952: 5951: 5946: 5935: 5934: 5915: 5913: 5912: 5907: 5896: 5895: 5860: 5858: 5857: 5852: 5813: 5811: 5810: 5805: 5760: 5758: 5757: 5752: 5741: 5740: 5681: 5663: 5661: 5660: 5655: 5653: 5652: 5647: 5622: 5620: 5619: 5614: 5567: 5566: 5516: 5514: 5513: 5508: 5442: 5440: 5439: 5434: 5386: 5384: 5383: 5378: 5331:. Then two maps 5326: 5324: 5323: 5318: 5307: 5306: 5280: 5278: 5277: 5272: 5270: 5262: 5244: 5242: 5241: 5236: 5234: 5226: 5154: 5152: 5151: 5146: 5132: 5131: 5104: 5103: 5082: 5081: 4962: 4960: 4959: 4954: 4940: 4939: 4912: 4911: 4887: 4886: 4881: 4852: 4850: 4849: 4844: 4839: 4838: 4829: 4824: 4823: 4805: 4804: 4795: 4790: 4789: 4771: 4770: 4761: 4756: 4755: 4737: 4736: 4727: 4722: 4721: 4697: 4696: 4678: 4677: 4642: 4640: 4639: 4634: 4623: 4622: 4607: 4606: 4601: 4534: 4532: 4531: 4526: 4524: 4523: 4518: 4443: 4441: 4440: 4435: 4433: 4432: 4307: 4305: 4304: 4299: 4236: 4234: 4233: 4228: 4177: 4138: 4136: 4135: 4130: 4098: 4097: 4014: 4012: 4011: 4006: 3964: 3963: 3958: 3949: 3948: 3943: 3914: 3912: 3911: 3906: 3822: 3820: 3819: 3814: 3781: 3780: 3720: 3719: 3695: 3693: 3692: 3687: 3586:, the functions 3549: 3547: 3546: 3541: 3533: 3507: 3506: 3466: 3464: 3463: 3458: 3444: 3443: 3438: 3429: 3428: 3423: 3376:is divisible by 3359: 3357: 3356: 3351: 3349: 3347: 3346: 3334: 3329: 3327: 3326: 3314: 3299: 3297: 3296: 3291: 3286: 3285: 3248: 3246: 3245: 3240: 3229: 3228: 3198: 3197: 3179: 3178: 3173: 3146: 3145: 3144: 3143: 3138: 3114: 3112: 3111: 3106: 3086: 3085: 3080: 3062: 3061: 3060: 3059: 3054: 3020: 3006: 3004: 3003: 2998: 2996: 2994: 2980: 2934: 2932: 2931: 2926: 2921: 2916: 2905: 2850: 2848: 2847: 2842: 2837: 2836: 2788: 2787: 2769: 2768: 2731: 2729: 2728: 2723: 2672: 2670: 2669: 2664: 2650: 2649: 2631: 2630: 2575: 2574: 2558: 2556: 2555: 2550: 2539: 2538: 2520: 2519: 2491: 2490: 2485: 2466: 2464: 2463: 2458: 2456: 2455: 2443: 2442: 2430: 2429: 2398: 2396: 2395: 2390: 2385: 2384: 2344: 2342: 2341: 2336: 2309: 2308: 2303: 2278: 2276: 2275: 2270: 2268: 2267: 2196:full subcategory 2190: 2188: 2187: 2182: 2132: 2131: 2126: 2125: 2095: 2093: 2092: 2087: 2085: 2084: 2070: 2069: 2059: 2058: 2053: 2052: 2035: 2033: 2032: 2027: 2022: 2021: 2016: 2015: 2005: 2004: 1989: 1988: 1974: 1973: 1956: 1954: 1953: 1948: 1946: 1945: 1923: 1897:integral domains 1860: 1858: 1857: 1852: 1847: 1846: 1837: 1836: 1821: 1820: 1798: 1797: 1778: 1719: 1717: 1716: 1711: 1706: 1698: 1659: 1657: 1656: 1651: 1649: 1641: 1632: 1630: 1629: 1624: 1619: 1611: 1572: 1570: 1569: 1564: 1562: 1554: 1442:complex analysis 1422:smooth functions 1360:For example, if 1348: 1346: 1345: 1340: 1329: 1328: 1323: 1322: 1321: 1303: 1301: 1300: 1295: 1287: 1286: 1281: 1280: 1279: 1261: 1259: 1258: 1253: 1251: 1250: 1234: 1232: 1231: 1226: 1224: 1223: 1218: 1210: 1197: 1195: 1194: 1189: 1181: 1176: 1175: 1166: 1146: 1141: 1140: 1131: 1117: 1116: 1098: 1096: 1095: 1090: 1082: 1074: 1073: 1055: 1054: 1014: 1012: 1011: 1006: 992: 991: 972: 970: 969: 964: 922: 920: 919: 914: 893: 891: 890: 885: 880: 879: 861: 860: 818: 816: 815: 810: 771: 769: 768: 763: 712: 711: 543: 541: 540: 535: 523: 521: 520: 515: 436: 434: 433: 428: 420: 412: 411: 393: 392: 344: 342: 341: 336: 334: 333: 314: 312: 311: 306: 301: 300: 282: 281: 253: 251: 250: 245: 243: 242: 237: 228: 227: 222: 206: 204: 203: 198: 173:affine varieties 170: 168: 167: 162: 160: 159: 154: 141: 139: 138: 133: 131: 130: 125: 56:regular function 21: 8089: 8088: 8084: 8083: 8082: 8080: 8079: 8078: 8054: 8053: 8052: 8046: 8036:Springer Verlag 8024: 8018: 7988: 7982: 7964:Springer-Verlag 7954: 7938: 7928:Springer-Verlag 7916: 7910: 7900:Springer Verlag 7888: 7882: 7862:Fulton, William 7860: 7856: 7851: 7843: 7839: 7831: 7827: 7821:Hartshorne 1997 7819: 7815: 7809:Hartshorne 1997 7807: 7803: 7794: 7790: 7784:Hartshorne 1997 7782: 7778: 7770: 7766: 7762: 7757: 7756: 7747: 7743: 7678: 7674: 7628: 7596: 7575: 7570: 7569: 7522: 7487: 7444: 7442: 7437: 7436: 7434: 7430: 7359: 7324: 7297: 7286: 7285: 7264: 7259: 7258: 7225: 7220: 7219: 7217: 7213: 7200: 7196: 7179: 7175: 7170: 7147:Étale morphisms 7142:Smooth morphism 7133: 7128: 7070: 7060: 7055: 7054: 6987: 6973: 6972: 6940: 6930: 6920: 6915: 6914: 6890: 6873: 6863: 6853: 6834: 6821: 6811: 6806: 6805: 6781: 6776: 6775: 6738: 6728: 6718: 6702: 6653: 6642: 6641: 6611: 6583: 6564: 6554: 6544: 6522: 6517: 6516: 6488:In general, if 6419: 6408: 6407: 6388:, then for any 6358: 6352: 6333: 6331: 6266: 6261: 6232: 6168: 6163: 6162: 6088: 6042: 6041: 6014: 6008: 5959: 5958: 5923: 5918: 5917: 5884: 5879: 5878: 5828: 5827: 5769: 5768: 5729: 5724: 5723: 5679: 5670: 5642: 5625: 5624: 5558: 5523: 5522: 5445: 5444: 5389: 5388: 5333: 5332: 5298: 5293: 5292: 5256: 5255: 5253: 5220: 5219: 5203: 5182: 5174:as long as the 5123: 5095: 5073: 5050: 5049: 5040: 5031: 5024: 5015: 5006: 4991: 4974: 4931: 4903: 4876: 4868: 4867: 4862: 4830: 4815: 4796: 4781: 4762: 4747: 4728: 4713: 4688: 4669: 4661: 4660: 4654: 4614: 4596: 4579: 4578: 4513: 4496: 4495: 4489: 4473:holomorphic map 4424: 4413: 4412: 4266: 4265: 4148: 4147: 4089: 4084: 4083: 3953: 3938: 3933: 3932: 3922: 3825: 3824: 3772: 3711: 3706: 3705: 3635: 3634: 3596:projective line 3581:algebraic curve 3498: 3493: 3492: 3433: 3418: 3413: 3412: 3338: 3318: 3302: 3301: 3274: 3251: 3250: 3217: 3186: 3168: 3133: 3128: 3117: 3116: 3075: 3049: 3044: 3039: 3038: 3011: 2984: 2953: 2952: 2906: 2878: 2877: 2860: 2825: 2779: 2760: 2734: 2733: 2702: 2701: 2677:is surjective). 2641: 2622: 2566: 2561: 2560: 2530: 2511: 2480: 2469: 2468: 2447: 2434: 2421: 2416: 2415: 2376: 2347: 2346: 2298: 2281: 2280: 2259: 2248: 2247: 2224: 2218: 2119: 2114: 2113: 2063: 2046: 2041: 2040: 2009: 1993: 1967: 1962: 1961: 1937: 1926: 1925: 1911: 1825: 1789: 1784: 1783: 1769: 1746: 1686: 1685: 1635: 1634: 1599: 1598: 1581:is of the form 1548: 1547: 1430:coordinate ring 1394: 1349:In particular, 1313: 1311: 1306: 1305: 1271: 1269: 1264: 1263: 1242: 1237: 1236: 1208: 1203: 1202: 1167: 1132: 1108: 1103: 1102: 1065: 1046: 1020: 1019: 983: 978: 977: 925: 924: 896: 895: 871: 852: 829: 828: 777: 776: 703: 698: 697: 526: 525: 494: 493: 464:if and only if 403: 384: 358: 357: 347:coordinate ring 325: 320: 319: 292: 273: 259: 258: 232: 217: 212: 211: 177: 176: 149: 144: 143: 120: 115: 114: 99: 32: 29:Biregular graph 23: 22: 15: 12: 11: 5: 8087: 8085: 8077: 8076: 8071: 8066: 8056: 8055: 8051: 8050: 8044: 8022: 8016: 7986: 7980: 7972:10.1007/b62130 7956:Mumford, David 7952: 7942: 7936: 7914: 7908: 7886: 7880: 7857: 7855: 7852: 7850: 7849: 7837: 7825: 7813: 7801: 7788: 7786:, Ch. I, § 3.. 7776: 7763: 7761: 7758: 7755: 7754: 7741: 7672: 7660: 7657: 7654: 7651: 7648: 7645: 7640: 7635: 7631: 7625: 7622: 7619: 7616: 7613: 7608: 7603: 7599: 7593: 7590: 7585: 7582: 7578: 7557: 7554: 7551: 7548: 7545: 7542: 7539: 7534: 7529: 7525: 7519: 7516: 7513: 7510: 7507: 7504: 7499: 7494: 7490: 7484: 7481: 7478: 7475: 7472: 7469: 7466: 7463: 7458: 7451: 7447: 7428: 7407: 7404: 7401: 7396: 7393: 7388: 7385: 7382: 7379: 7376: 7371: 7366: 7362: 7356: 7353: 7350: 7347: 7344: 7341: 7336: 7331: 7327: 7321: 7318: 7315: 7312: 7309: 7304: 7300: 7296: 7293: 7271: 7267: 7232: 7228: 7211: 7194: 7172: 7171: 7169: 7166: 7165: 7164: 7159: 7154: 7144: 7139: 7132: 7129: 7081: 7075: 7067: 7063: 7047: 7046: 7035: 7032: 7029: 7026: 7023: 7020: 7017: 7014: 7011: 7008: 7005: 7002: 6999: 6994: 6990: 6986: 6983: 6980: 6951: 6945: 6937: 6933: 6927: 6923: 6900: 6897: 6893: 6889: 6884: 6878: 6870: 6866: 6860: 6856: 6852: 6849: 6846: 6841: 6837: 6833: 6828: 6824: 6818: 6814: 6791: 6788: 6784: 6768: 6767: 6756: 6753: 6750: 6745: 6741: 6735: 6731: 6725: 6721: 6717: 6714: 6709: 6705: 6701: 6698: 6695: 6690: 6685: 6682: 6679: 6675: 6671: 6668: 6665: 6660: 6656: 6652: 6649: 6626: 6623: 6618: 6614: 6610: 6607: 6604: 6601: 6596: 6593: 6590: 6586: 6582: 6579: 6576: 6571: 6567: 6561: 6557: 6551: 6547: 6543: 6540: 6537: 6534: 6529: 6525: 6479: 6478: 6467: 6464: 6461: 6458: 6455: 6452: 6449: 6446: 6443: 6440: 6437: 6434: 6431: 6426: 6422: 6418: 6415: 6390:coherent sheaf 6354: 6348: 6327: 6265: 6262: 6228: 6227: 6216: 6213: 6210: 6207: 6204: 6201: 6198: 6195: 6192: 6189: 6186: 6183: 6180: 6175: 6171: 6144: 6143: 6132: 6129: 6126: 6118: 6115: 6112: 6109: 6106: 6103: 6098: 6095: 6091: 6082: 6079: 6076: 6073: 6070: 6067: 6064: 6061: 6058: 6055: 6052: 6049: 6009: 6007: 6006: 6005: 6004: 5993: 5990: 5987: 5984: 5981: 5978: 5975: 5972: 5969: 5966: 5944: 5941: 5938: 5933: 5930: 5926: 5905: 5902: 5899: 5894: 5891: 5887: 5850: 5847: 5844: 5841: 5838: 5835: 5826:such that (a) 5816: 5815: 5814: 5803: 5800: 5797: 5794: 5791: 5788: 5785: 5782: 5779: 5776: 5750: 5747: 5744: 5739: 5736: 5732: 5674: 5669: 5666: 5651: 5646: 5641: 5638: 5635: 5632: 5612: 5609: 5606: 5603: 5600: 5597: 5594: 5591: 5588: 5585: 5582: 5579: 5576: 5573: 5570: 5565: 5561: 5557: 5554: 5551: 5548: 5545: 5542: 5539: 5536: 5533: 5530: 5506: 5503: 5500: 5497: 5494: 5491: 5488: 5485: 5482: 5479: 5476: 5473: 5470: 5467: 5464: 5461: 5458: 5455: 5452: 5432: 5429: 5426: 5423: 5420: 5417: 5414: 5411: 5408: 5405: 5402: 5399: 5396: 5376: 5373: 5370: 5367: 5364: 5361: 5358: 5355: 5352: 5349: 5346: 5343: 5340: 5316: 5313: 5310: 5305: 5301: 5268: 5265: 5249: 5232: 5229: 5199: 5178: 5156: 5155: 5144: 5141: 5138: 5135: 5130: 5126: 5122: 5119: 5116: 5113: 5110: 5107: 5102: 5098: 5094: 5091: 5088: 5085: 5080: 5076: 5072: 5069: 5066: 5063: 5060: 5057: 5036: 5029: 5020: 5011: 5004: 4987: 4970: 4964: 4963: 4952: 4949: 4946: 4943: 4938: 4934: 4930: 4927: 4924: 4921: 4918: 4915: 4910: 4906: 4902: 4899: 4896: 4893: 4890: 4885: 4880: 4875: 4858: 4842: 4837: 4833: 4828: 4822: 4818: 4814: 4811: 4808: 4803: 4799: 4794: 4788: 4784: 4780: 4777: 4774: 4769: 4765: 4760: 4754: 4750: 4746: 4743: 4740: 4735: 4731: 4726: 4720: 4716: 4712: 4709: 4706: 4703: 4700: 4695: 4691: 4687: 4684: 4681: 4676: 4672: 4668: 4650: 4644: 4643: 4632: 4629: 4626: 4621: 4617: 4613: 4610: 4605: 4600: 4595: 4592: 4589: 4586: 4546:be a point of 4536: 4535: 4522: 4517: 4512: 4509: 4506: 4503: 4488: 4485: 4454:normal variety 4431: 4427: 4423: 4420: 4392:smooth variety 4388:normal variety 4297: 4294: 4291: 4288: 4285: 4282: 4279: 4276: 4273: 4238: 4237: 4226: 4223: 4220: 4217: 4214: 4210: 4207: 4204: 4201: 4198: 4195: 4192: 4189: 4186: 4183: 4180: 4175: 4172: 4167: 4164: 4161: 4158: 4155: 4128: 4125: 4122: 4119: 4116: 4113: 4110: 4107: 4104: 4101: 4096: 4092: 4004: 4001: 3998: 3995: 3992: 3989: 3986: 3983: 3980: 3977: 3974: 3971: 3967: 3962: 3957: 3952: 3947: 3942: 3921: 3918: 3917: 3916: 3904: 3901: 3898: 3895: 3892: 3889: 3886: 3883: 3880: 3877: 3874: 3871: 3868: 3865: 3862: 3859: 3856: 3853: 3850: 3847: 3844: 3841: 3838: 3835: 3832: 3812: 3809: 3806: 3803: 3800: 3796: 3793: 3790: 3787: 3784: 3779: 3775: 3771: 3768: 3765: 3762: 3759: 3756: 3753: 3750: 3747: 3744: 3741: 3738: 3735: 3732: 3729: 3726: 3723: 3718: 3714: 3685: 3682: 3679: 3676: 3673: 3670: 3667: 3663: 3660: 3657: 3654: 3651: 3648: 3645: 3642: 3623: 3567:function field 3563: 3539: 3536: 3532: 3528: 3525: 3522: 3519: 3516: 3513: 3510: 3505: 3501: 3456: 3453: 3450: 3447: 3442: 3437: 3432: 3427: 3422: 3409: 3345: 3341: 3337: 3332: 3325: 3321: 3317: 3312: 3309: 3289: 3284: 3281: 3277: 3273: 3270: 3267: 3264: 3261: 3258: 3238: 3235: 3232: 3227: 3224: 3220: 3216: 3213: 3210: 3207: 3204: 3201: 3196: 3193: 3189: 3185: 3182: 3177: 3172: 3167: 3164: 3161: 3158: 3155: 3152: 3149: 3142: 3137: 3131: 3127: 3124: 3104: 3101: 3098: 3095: 3092: 3089: 3084: 3079: 3074: 3071: 3068: 3065: 3058: 3053: 3047: 3037:is regular on 3008: 2993: 2990: 2987: 2983: 2978: 2975: 2972: 2969: 2966: 2963: 2960: 2924: 2919: 2915: 2912: 2909: 2903: 2900: 2897: 2894: 2891: 2888: 2885: 2862: 2856: 2840: 2835: 2832: 2828: 2824: 2821: 2818: 2815: 2812: 2809: 2806: 2803: 2800: 2797: 2794: 2791: 2786: 2782: 2778: 2775: 2772: 2767: 2763: 2759: 2756: 2753: 2750: 2747: 2744: 2741: 2721: 2718: 2715: 2712: 2709: 2678: 2662: 2659: 2656: 2653: 2648: 2644: 2640: 2637: 2634: 2629: 2625: 2621: 2618: 2615: 2612: 2608: 2605: 2602: 2599: 2596: 2593: 2590: 2587: 2584: 2581: 2578: 2573: 2569: 2548: 2545: 2542: 2537: 2533: 2529: 2526: 2523: 2518: 2514: 2510: 2507: 2504: 2500: 2497: 2494: 2489: 2484: 2479: 2476: 2454: 2450: 2446: 2441: 2437: 2433: 2428: 2424: 2408: 2388: 2383: 2379: 2375: 2372: 2369: 2366: 2363: 2360: 2357: 2354: 2334: 2331: 2328: 2325: 2322: 2319: 2316: 2312: 2307: 2302: 2297: 2294: 2291: 2288: 2266: 2262: 2258: 2255: 2240: 2217: 2214: 2180: 2177: 2174: 2171: 2168: 2165: 2162: 2159: 2156: 2153: 2150: 2147: 2144: 2141: 2138: 2135: 2130: 2124: 2098:maximal ideals 2083: 2080: 2077: 2074: 2068: 2062: 2057: 2051: 2037: 2036: 2025: 2020: 2014: 2008: 2003: 2000: 1996: 1992: 1987: 1984: 1981: 1978: 1972: 1944: 1940: 1936: 1933: 1864:by taking the 1862: 1861: 1850: 1845: 1840: 1835: 1832: 1828: 1824: 1819: 1813: 1810: 1807: 1804: 1801: 1796: 1792: 1766:affine schemes 1745: 1742: 1709: 1704: 1701: 1696: 1693: 1647: 1644: 1622: 1617: 1614: 1609: 1606: 1560: 1557: 1393: 1390: 1338: 1335: 1332: 1327: 1320: 1316: 1293: 1290: 1285: 1278: 1274: 1249: 1245: 1222: 1216: 1213: 1199: 1198: 1187: 1184: 1179: 1174: 1170: 1164: 1161: 1158: 1155: 1152: 1149: 1144: 1139: 1135: 1129: 1126: 1123: 1120: 1115: 1111: 1088: 1085: 1081: 1077: 1072: 1068: 1064: 1061: 1058: 1053: 1049: 1045: 1042: 1039: 1036: 1033: 1030: 1027: 1016: 1015: 1004: 1001: 998: 995: 990: 986: 962: 959: 956: 953: 950: 947: 944: 941: 938: 935: 932: 912: 909: 906: 903: 883: 878: 874: 870: 867: 864: 859: 855: 851: 848: 845: 842: 839: 836: 808: 805: 802: 799: 796: 793: 790: 787: 784: 773: 772: 761: 758: 755: 752: 749: 745: 742: 739: 736: 733: 730: 727: 724: 721: 718: 715: 710: 706: 668: 667: 533: 513: 510: 507: 504: 501: 438: 437: 426: 423: 419: 415: 410: 406: 402: 399: 396: 391: 387: 383: 380: 377: 374: 371: 368: 365: 332: 328: 316: 315: 304: 299: 295: 291: 288: 285: 280: 276: 272: 269: 266: 241: 236: 231: 226: 221: 209:polynomial map 196: 193: 190: 187: 184: 158: 153: 129: 124: 98: 95: 24: 14: 13: 10: 9: 6: 4: 3: 2: 8086: 8075: 8072: 8070: 8067: 8065: 8062: 8061: 8059: 8047: 8041: 8037: 8033: 8032: 8027: 8023: 8019: 8013: 8009: 8005: 8001: 7997: 7996: 7991: 7987: 7983: 7977: 7973: 7969: 7965: 7961: 7957: 7953: 7950: 7946: 7943: 7939: 7937:0-387-90244-9 7933: 7929: 7925: 7924: 7919: 7915: 7911: 7905: 7901: 7897: 7896: 7891: 7887: 7883: 7877: 7873: 7869: 7868: 7863: 7859: 7858: 7853: 7846: 7841: 7838: 7834: 7829: 7826: 7822: 7817: 7814: 7810: 7805: 7802: 7798: 7792: 7789: 7785: 7780: 7777: 7773: 7768: 7765: 7759: 7751: 7745: 7742: 7738: 7734: 7730: 7726: 7722: 7718: 7714: 7710: 7706: 7702: 7698: 7694: 7690: 7686: 7682: 7676: 7673: 7658: 7655: 7652: 7646: 7643: 7633: 7629: 7623: 7620: 7617: 7614: 7611: 7601: 7597: 7588: 7583: 7576: 7552: 7546: 7543: 7527: 7523: 7514: 7511: 7508: 7505: 7492: 7488: 7479: 7473: 7470: 7464: 7449: 7445: 7432: 7429: 7425: 7421: 7405: 7402: 7391: 7383: 7380: 7364: 7360: 7351: 7348: 7345: 7342: 7329: 7325: 7316: 7310: 7307: 7302: 7298: 7294: 7291: 7269: 7265: 7256: 7252: 7248: 7230: 7226: 7218:The image of 7215: 7212: 7208: 7204: 7198: 7195: 7191: 7187: 7183: 7177: 7174: 7167: 7163: 7160: 7158: 7155: 7152: 7148: 7145: 7143: 7140: 7138: 7135: 7134: 7130: 7127: 7122: 7120: 7116: 7112: 7108: 7105:is étale and 7104: 7099: 7097: 7079: 7065: 7061: 7052: 7030: 7024: 7021: 7015: 7009: 7006: 7003: 6997: 6992: 6988: 6981: 6978: 6971: 6970: 6969: 6967: 6949: 6935: 6931: 6925: 6921: 6898: 6895: 6891: 6887: 6882: 6868: 6864: 6858: 6854: 6850: 6844: 6839: 6835: 6826: 6822: 6816: 6812: 6789: 6786: 6782: 6773: 6754: 6748: 6743: 6739: 6733: 6729: 6723: 6719: 6712: 6707: 6699: 6696: 6683: 6680: 6677: 6673: 6669: 6663: 6658: 6654: 6647: 6640: 6639: 6638: 6621: 6616: 6612: 6608: 6605: 6599: 6594: 6591: 6588: 6574: 6569: 6565: 6559: 6555: 6549: 6545: 6541: 6538: 6532: 6527: 6515: 6511: 6507: 6503: 6499: 6495: 6491: 6486: 6484: 6465: 6459: 6453: 6447: 6441: 6438: 6435: 6429: 6424: 6420: 6413: 6406: 6405: 6404: 6402: 6398: 6394: 6391: 6387: 6383: 6379: 6375: 6371: 6366: 6364: 6360: 6357: 6351: 6347: 6340: 6336: 6330: 6326: 6322: 6318: 6314: 6310: 6306: 6303: 6299: 6295: 6291: 6287: 6283: 6279: 6275: 6271: 6263: 6260: 6255: 6253: 6249: 6245: 6241: 6237: 6231: 6211: 6208: 6202: 6196: 6193: 6190: 6187: 6184: 6178: 6173: 6169: 6161: 6160: 6159: 6157: 6153: 6149: 6130: 6124: 6110: 6104: 6096: 6093: 6089: 6080: 6077: 6074: 6071: 6068: 6059: 6053: 6047: 6040: 6039: 6038: 6036: 6032: 6028: 6024: 6020: 5991: 5988: 5985: 5982: 5979: 5976: 5973: 5970: 5967: 5964: 5957: 5956: 5939: 5931: 5928: 5924: 5916:intersecting 5900: 5892: 5889: 5885: 5876: 5872: 5869:intersecting 5868: 5864: 5845: 5839: 5836: 5833: 5825: 5821: 5817: 5801: 5798: 5795: 5792: 5789: 5786: 5783: 5780: 5777: 5774: 5767: 5766: 5764: 5745: 5737: 5734: 5730: 5721: 5717: 5713: 5709: 5708: 5707: 5705: 5701: 5697: 5693: 5689: 5685: 5673: 5667: 5665: 5649: 5636: 5633: 5630: 5607: 5604: 5601: 5595: 5589: 5586: 5583: 5580: 5577: 5571: 5563: 5559: 5555: 5552: 5549: 5543: 5537: 5534: 5531: 5520: 5501: 5498: 5495: 5492: 5489: 5486: 5483: 5480: 5477: 5474: 5468: 5465: 5462: 5459: 5456: 5427: 5424: 5421: 5409: 5406: 5403: 5400: 5397: 5371: 5368: 5365: 5353: 5350: 5347: 5344: 5341: 5330: 5314: 5311: 5308: 5303: 5299: 5291:be the conic 5290: 5286: 5282: 5263: 5252: 5248: 5227: 5217: 5214: 5209: 5207: 5202: 5198: 5194: 5190: 5186: 5181: 5177: 5173: 5169: 5165: 5161: 5136: 5128: 5124: 5120: 5117: 5114: 5108: 5100: 5096: 5092: 5086: 5078: 5074: 5067: 5061: 5055: 5048: 5047: 5046: 5044: 5039: 5035: 5028: 5023: 5019: 5014: 5010: 5003: 4999: 4995: 4990: 4986: 4982: 4978: 4973: 4969: 4944: 4936: 4932: 4928: 4925: 4922: 4916: 4908: 4904: 4897: 4891: 4883: 4873: 4866: 4865: 4864: 4861: 4856: 4835: 4831: 4826: 4820: 4816: 4812: 4809: 4806: 4801: 4797: 4792: 4786: 4782: 4775: 4767: 4763: 4758: 4752: 4748: 4744: 4741: 4738: 4733: 4729: 4724: 4718: 4714: 4710: 4707: 4701: 4693: 4689: 4685: 4682: 4679: 4674: 4670: 4658: 4653: 4649: 4627: 4624: 4619: 4615: 4608: 4603: 4590: 4587: 4584: 4577: 4576: 4575: 4573: 4569: 4565: 4561: 4557: 4553: 4549: 4545: 4541: 4520: 4507: 4504: 4501: 4494: 4493: 4492: 4486: 4484: 4482: 4478: 4474: 4470: 4465: 4463: 4459: 4455: 4451: 4447: 4429: 4425: 4418: 4411: 4407: 4406:homeomorphism 4402: 4400: 4397: 4393: 4389: 4384: 4382: 4378: 4374: 4370: 4366: 4362: 4358: 4354: 4350: 4346: 4342: 4338: 4334: 4329: 4327: 4323: 4319: 4315: 4311: 4292: 4286: 4277: 4271: 4263: 4259: 4255: 4254:generic point 4251: 4250:residue field 4247: 4243: 4224: 4221: 4218: 4212: 4208: 4202: 4196: 4187: 4181: 4178: 4173: 4170: 4165: 4159: 4153: 4146: 4145: 4144: 4142: 4123: 4117: 4108: 4102: 4099: 4090: 4081: 4077: 4073: 4069: 4065: 4061: 4057: 4053: 4049: 4045: 4041: 4037: 4032: 4030: 4026: 4022: 4018: 3999: 3996: 3993: 3990: 3978: 3975: 3972: 3965: 3960: 3945: 3929: 3927: 3919: 3899: 3893: 3890: 3881: 3878: 3875: 3869: 3863: 3860: 3854: 3851: 3848: 3839: 3836: 3833: 3810: 3807: 3804: 3798: 3794: 3788: 3782: 3777: 3773: 3766: 3760: 3757: 3751: 3748: 3745: 3739: 3730: 3724: 3721: 3712: 3703: 3699: 3683: 3674: 3671: 3668: 3661: 3658: 3652: 3649: 3646: 3643: 3640: 3632: 3628: 3624: 3621: 3617: 3613: 3609: 3605: 3601: 3597: 3593: 3589: 3585: 3582: 3579: 3575: 3571: 3568: 3564: 3561: 3557: 3553: 3534: 3530: 3526: 3520: 3517: 3511: 3499: 3490: 3486: 3482: 3478: 3474: 3470: 3445: 3440: 3430: 3425: 3410: 3407: 3403: 3399: 3395: 3391: 3387: 3383: 3379: 3375: 3371: 3367: 3363: 3343: 3339: 3335: 3330: 3323: 3319: 3315: 3310: 3307: 3282: 3279: 3275: 3271: 3268: 3265: 3262: 3256: 3233: 3230: 3225: 3222: 3218: 3214: 3211: 3205: 3202: 3194: 3191: 3187: 3175: 3162: 3159: 3150: 3140: 3129: 3122: 3115:and so is in 3099: 3096: 3093: 3087: 3082: 3072: 3066: 3056: 3045: 3036: 3032: 3028: 3024: 3018: 3014: 3009: 2991: 2988: 2985: 2981: 2976: 2970: 2967: 2964: 2958: 2950: 2946: 2942: 2938: 2922: 2917: 2913: 2910: 2907: 2901: 2895: 2892: 2889: 2883: 2875: 2871: 2867: 2863: 2859: 2854: 2833: 2830: 2822: 2819: 2816: 2810: 2807: 2801: 2792: 2789: 2784: 2780: 2776: 2773: 2770: 2765: 2761: 2754: 2751: 2745: 2739: 2719: 2713: 2710: 2707: 2699: 2695: 2691: 2687: 2683: 2679: 2676: 2660: 2654: 2651: 2646: 2642: 2638: 2635: 2632: 2627: 2623: 2616: 2610: 2606: 2600: 2594: 2585: 2579: 2576: 2567: 2543: 2540: 2535: 2531: 2527: 2524: 2521: 2516: 2512: 2502: 2498: 2495: 2487: 2477: 2474: 2452: 2448: 2444: 2439: 2435: 2431: 2426: 2422: 2413: 2409: 2406: 2402: 2381: 2377: 2373: 2370: 2364: 2358: 2352: 2332: 2323: 2320: 2317: 2310: 2305: 2292: 2289: 2286: 2264: 2260: 2256: 2253: 2245: 2241: 2238: 2234: 2230: 2226: 2225: 2223: 2215: 2213: 2211: 2207: 2205: 2201: 2197: 2192: 2175: 2172: 2166: 2160: 2157: 2151: 2145: 2142: 2139: 2133: 2128: 2111: 2107: 2103: 2099: 2078: 2072: 2060: 2055: 2018: 2001: 1998: 1994: 1990: 1982: 1976: 1960: 1959: 1958: 1938: 1934: 1931: 1922: 1918: 1914: 1910:. (Proof: If 1909: 1905: 1902: 1898: 1894: 1890: 1886: 1882: 1877: 1875: 1871: 1867: 1833: 1830: 1826: 1811: 1808: 1802: 1799: 1794: 1790: 1782: 1781: 1780: 1777: 1773: 1767: 1763: 1759: 1755: 1751: 1743: 1741: 1739: 1735: 1731: 1727: 1723: 1699: 1691: 1683: 1679: 1675: 1671: 1667: 1663: 1642: 1612: 1604: 1596: 1592: 1588: 1584: 1580: 1576: 1555: 1545: 1541: 1537: 1533: 1528: 1526: 1522: 1518: 1514: 1510: 1506: 1502: 1498: 1494: 1490: 1486: 1482: 1478: 1474: 1470: 1466: 1462: 1458: 1454: 1450: 1445: 1443: 1439: 1435: 1431: 1428:(that is the 1427: 1423: 1419: 1415: 1411: 1407: 1403: 1399: 1391: 1389: 1387: 1383: 1379: 1375: 1371: 1367: 1363: 1358: 1356: 1352: 1336: 1333: 1330: 1325: 1314: 1291: 1288: 1276: 1272: 1247: 1243: 1220: 1211: 1172: 1168: 1159: 1156: 1153: 1150: 1137: 1133: 1124: 1118: 1113: 1109: 1101: 1100: 1099: 1086: 1083: 1079: 1070: 1066: 1062: 1059: 1056: 1051: 1047: 1040: 1037: 1031: 1025: 1002: 996: 993: 988: 984: 976: 975: 974: 957: 951: 942: 936: 933: 930: 907: 901: 876: 872: 868: 865: 862: 857: 853: 846: 843: 840: 837: 834: 826: 822: 803: 797: 794: 788: 782: 759: 756: 753: 747: 743: 737: 731: 722: 716: 713: 704: 696: 695: 694: 692: 688: 684: 680: 675: 673: 665: 660: 656: 652: 648: 644: 640: 637: 636: 635: 633: 629: 625: 621: 617: 613: 609: 605: 601: 597: 593: 589: 585: 581: 577: 573: 569: 566: 562: 558: 554: 550: 545: 531: 511: 505: 502: 499: 491: 487: 483: 479: 476:). The image 475: 471: 468: −  467: 463: 459: 455: 451: 447: 443: 424: 421: 417: 408: 404: 400: 397: 394: 389: 385: 378: 375: 369: 363: 356: 355: 354: 352: 348: 345:s are in the 330: 326: 297: 293: 289: 286: 283: 278: 274: 267: 264: 257: 256: 255: 239: 224: 210: 194: 188: 185: 182: 174: 171:(so they are 156: 127: 112: 108: 104: 96: 94: 92: 87: 85: 81: 77: 73: 69: 65: 61: 57: 53: 49: 45: 41: 37: 30: 19: 8030: 7994: 7959: 7921: 7894: 7866: 7840: 7833:Mumford 1999 7828: 7816: 7804: 7791: 7779: 7767: 7744: 7736: 7732: 7728: 7724: 7720: 7716: 7712: 7708: 7704: 7700: 7696: 7692: 7688: 7684: 7680: 7675: 7431: 7423: 7419: 7254: 7250: 7246: 7214: 7206: 7202: 7197: 7185: 7181: 7176: 7118: 7114: 7110: 7106: 7102: 7100: 7095: 7051:generic rank 7048: 6965: 6771: 6769: 6637:, one gets: 6509: 6505: 6497: 6493: 6489: 6487: 6480: 6396: 6392: 6381: 6377: 6369: 6367: 6362: 6355: 6349: 6345: 6338: 6334: 6328: 6324: 6320: 6316: 6308: 6304: 6301: 6297: 6293: 6289: 6285: 6277: 6273: 6269: 6267: 6247: 6233: 6229: 6155: 6147: 6145: 6034: 6030: 6026: 6022: 6018: 6010: 5874: 5870: 5866: 5862: 5823: 5819: 5762: 5719: 5715: 5711: 5703: 5699: 5695: 5691: 5687: 5683: 5675: 5671: 5518: 5328: 5288: 5284: 5283: 5250: 5246: 5215: 5210: 5205: 5200: 5196: 5192: 5188: 5184: 5179: 5175: 5171: 5167: 5163: 5159: 5157: 5042: 5037: 5033: 5026: 5021: 5017: 5012: 5008: 5001: 4997: 4993: 4988: 4984: 4980: 4976: 4971: 4967: 4965: 4863:is given by 4859: 4854: 4656: 4651: 4647: 4645: 4571: 4567: 4563: 4559: 4555: 4551: 4550:. Then some 4547: 4543: 4537: 4490: 4466: 4457: 4449: 4445: 4403: 4385: 4380: 4376: 4372: 4368: 4364: 4360: 4356: 4352: 4348: 4344: 4340: 4336: 4332: 4330: 4325: 4321: 4317: 4313: 4310:rational map 4261: 4257: 4245: 4242:direct limit 4239: 4140: 4079: 4075: 4071: 4067: 4063: 4059: 4055: 4051: 4047: 4043: 4039: 4035: 4033: 4025:dense subset 4020: 4016: 3930: 3923: 3701: 3697: 3630: 3626: 3619: 3615: 3611: 3599: 3591: 3587: 3583: 3573: 3569: 3559: 3555: 3551: 3488: 3484: 3480: 3476: 3472: 3468: 3405: 3401: 3397: 3393: 3389: 3385: 3381: 3377: 3373: 3369: 3365: 3361: 3034: 3030: 3026: 3022: 3016: 3012: 2948: 2944: 2940: 2936: 2876:= 1 and let 2873: 2869: 2865: 2857: 2852: 2697: 2693: 2689: 2685: 2681: 2674: 2411: 2404: 2400: 2243: 2236: 2232: 2228: 2208: 2203: 2199: 2193: 2109: 2105: 2101: 2038: 1920: 1916: 1912: 1903: 1892: 1888: 1884: 1880: 1878: 1876:in general. 1870:prime ideals 1863: 1775: 1771: 1761: 1757: 1753: 1749: 1747: 1737: 1733: 1729: 1725: 1721: 1681: 1677: 1673: 1669: 1665: 1594: 1590: 1586: 1582: 1578: 1574: 1543: 1539: 1531: 1529: 1520: 1516: 1512: 1508: 1504: 1500: 1496: 1492: 1488: 1484: 1480: 1476: 1472: 1464: 1460: 1456: 1452: 1448: 1446: 1417: 1413: 1409: 1405: 1401: 1397: 1395: 1381: 1377: 1373: 1369: 1365: 1361: 1359: 1354: 1350: 1200: 1017: 824: 820: 774: 690: 686: 682: 676: 669: 664:ringed space 658: 654: 650: 646: 642: 638: 631: 627: 623: 619: 615: 611: 607: 603: 599: 595: 591: 590:) such that 587: 583: 579: 575: 571: 567: 564: 559:between two 556: 552: 548: 546: 489: 485: 481: 477: 473: 469: 465: 461: 457: 453: 449: 441: 439: 350: 317: 111:subvarieties 106: 102: 100: 88: 64:isomorphisms 59: 55: 47: 33: 7945:James Milne 7890:Harris, Joe 7845:Fulton 1998 7727:; that is, 7679:Proof: Let 7049:(since the 6343:is free as 6230:is closed. 5761:dominating 4260:to that of 4034:A morphism 3604:#Properties 3578:irreducible 3565:Taking the 1908:#Definition 1416:are called 1304:as well as 109:are closed 52:affine line 48:regular map 44:polynomials 8058:Categories 7981:354063293X 7854:References 7699:with some 7124:See also: 7121:) points. 6257:See also: 6158:, the set 4574:such that 4240:where the 4070:such that 3926:continuous 3920:Properties 2220:See also: 1866:pre-images 1720:such that 1487:such that 1467:, it is a 626:is called 484:) lies in 318:where the 97:Definition 76:birational 7760:Citations 7644:∘ 7639:¯ 7621:… 7612:∘ 7607:¯ 7581:# 7547:ϕ 7533:¯ 7515:ϕ 7509:… 7498:¯ 7480:ϕ 7457:# 7446:ϕ 7395:¯ 7384:ϕ 7370:¯ 7352:ϕ 7346:… 7335:¯ 7317:ϕ 7299:ϕ 7295:∘ 7266:ϕ 7249:since if 7227:ϕ 7066:∗ 7025:⁡ 7010:⁡ 6993:∗ 6982:⁡ 6936:∗ 6896:⊗ 6888:⊗ 6869:∗ 6840:∗ 6827:∗ 6787:⊗ 6744:∗ 6734:∗ 6713:χ 6697:− 6689:∞ 6674:∑ 6659:∗ 6648:χ 6617:∗ 6600:⁡ 6581:⇒ 6570:∗ 6560:∗ 6533:⁡ 6454:χ 6442:⁡ 6425:∗ 6414:χ 6209:≥ 6194:∣ 6188:∈ 6094:− 6078:∣ 6072:⁡ 6037:, define 6012:Corollary 5980:⁡ 5968:⁡ 5929:− 5890:− 5837:⊂ 5790:⁡ 5784:≥ 5778:⁡ 5735:− 5640:→ 5499:≠ 5487:≠ 5481:∣ 5475:∈ 5416:↦ 5360:↦ 5267:¯ 5231:¯ 5118:⋯ 4926:… 4810:… 4776:∼ 4742:⋯ 4683:⋯ 4609:− 4594:→ 4511:→ 4477:removable 4422:↦ 4339:) and if 4284:↪ 4222:∘ 4216:↦ 4194:↪ 4179:⁡ 4174:→ 4115:→ 4095:# 4082:and then 3985:↦ 3951:→ 3837:⊗ 3808:⊗ 3802:↦ 3774:⊗ 3749:× 3737:→ 3717:# 3681:↦ 3656:→ 3650:× 3504:# 3500:σ 3452:∞ 3446:∪ 3280:− 3223:− 3192:− 3088:− 2911:− 2831:− 2820:− 2799:↪ 2790:− 2771:− 2717:→ 2652:− 2633:− 2614:↦ 2592:→ 2572:# 2541:− 2522:− 2506:↦ 2493:→ 2330:↦ 2296:→ 2158:∣ 2143:∈ 2112:); i.e., 1999:− 1995:ϕ 1943:# 1932:ϕ 1831:− 1827:ϕ 1823:↦ 1806:→ 1791:ϕ 1770:ϕ : 1703:¯ 1646:¯ 1616:¯ 1559:¯ 1386:#Examples 1319:# 1292:ϕ 1284:# 1273:ϕ 1262:'s. Note 1215:¯ 1178:¯ 1160:ϕ 1154:… 1143:¯ 1125:ϕ 1110:ϕ 1060:… 1000:→ 985:ϕ 949:→ 931:ϕ 866:… 838:∘ 757:∘ 751:↦ 729:→ 709:# 561:varieties 509:→ 448:defining 398:… 287:… 230:→ 192:→ 186:: 60:biregular 8028:(2009). 7992:(2013). 7958:(1999). 7920:(1997). 7892:(1992). 7864:(1998). 7245:lies in 7131:See also 6502:complete 6386:complete 5158:for all 4979:. Since 4048:dominant 3576:) of an 3411:Suppose 3388:is just 3019:− (0, 0) 2399:. Since 2216:Examples 2096:are the 1915: : 1879:Now, if 1525:Examples 72:rational 7795:Vakil, 7715:, then 7435:Proof: 6376:and if 6359:-module 6300:) over 5706:. Then 5677:Theorem 5521:(since 4456:, then 4351:, then 4252:of the 3602:. (cf. 3594:to the 3491:, then 3380:and so 3033:, then 3021:. Then 2467:. Then 2279:. Then 1760:= Spec 1752:= Spec 1523:); see 1400:equals 628:regular 622:. Then 444:is the 8042:  8014:  7978:  7934:  7906:  7878:  7719:is in 7422:is in 7418:since 6353:| 6311:). By 6282:finite 5698:= dim 5041:'s in 4966:where 3823:where 3360:where 2039:where 1384:. See 1201:where 775:where 472:is in 440:where 7687:. If 7168:Notes 6481:(The 6374:étale 6280:be a 6146:Then 4471:is a 4452:is a 4386:On a 4312:from 4054:, if 3598:over 2935:Then 2696:= 1, 1660:(cf. 1534:is a 1483:near 639:Note: 446:ideal 8040:ISBN 8012:ISBN 7976:ISBN 7932:ISBN 7904:ISBN 7876:ISBN 6504:and 6500:are 6384:are 6268:Let 6252:flat 6017:Let 5682:Let 5387:and 5285:Note 4491:Let 4078:) ⊂ 3700:and 3550:and 3010:Let 2864:Let 2410:Let 2242:Let 2104:and 1895:are 1764:are 1756:and 1732:and 1499:and 1368:and 823:and 645:and 618:and 598:) ⊂ 456:and 142:and 105:and 74:and 8004:doi 7968:doi 7711:in 7703:in 7101:If 7098:.) 7053:of 7022:deg 7007:deg 6979:deg 6439:deg 6403:, 6395:on 6372:is 6368:If 6332:to 6319:in 6250:is 6150:is 6069:dim 6063:max 6033:in 5977:dim 5965:dim 5877:of 5865:of 5822:in 5787:dim 5775:dim 5722:of 5714:of 5517:of 5327:in 5191:of 5170:in 5162:in 4996:of 4570:of 4464:.) 4331:If 4316:to 4256:of 4171:lim 4066:of 4031:). 3558:(1/ 3475:on 1868:of 1748:If 1668:on 1633:of 1573:of 1530:If 1444:). 1440:in 1380:to 582:of 574:of 563:is 349:of 113:of 101:If 34:In 8060:: 8038:. 8010:. 8002:. 7998:. 7974:. 7966:. 7947:, 7930:. 7926:. 7902:. 7898:. 7874:. 7870:. 7739:). 7723:= 7691:= 7205:, 7184:= 6496:, 6380:, 6276:→ 6272:: 6025:→ 6021:: 5955:, 5765:, 5690:→ 5686:: 5664:. 5281:. 5016:= 4401:. 4383:. 4375:→ 4359:→ 4328:. 3629:, 3408:.) 3404:= 3364:, 3015:= 2947:, 2872:+ 2684:= 2212:. 2206:. 1919:→ 1891:, 1883:, 1774:→ 1724:= 1680:, 1593:, 1527:. 1519:, 1511:, 1491:= 1479:, 634:. 544:. 353:: 8048:. 8020:. 8006:: 7984:. 7970:: 7940:. 7912:. 7884:. 7737:h 7735:( 7733:D 7729:f 7725:k 7721:A 7717:f 7713:A 7709:h 7705:A 7701:g 7697:h 7695:/ 7693:g 7689:f 7685:x 7681:A 7659:. 7656:f 7653:= 7650:) 7647:f 7634:m 7630:y 7624:, 7618:, 7615:f 7602:1 7598:y 7592:( 7589:= 7584:a 7577:f 7556:) 7553:g 7550:( 7544:= 7541:) 7538:) 7528:m 7524:y 7518:( 7512:, 7506:, 7503:) 7493:1 7489:y 7483:( 7477:( 7474:g 7471:= 7468:) 7465:g 7462:( 7450:a 7426:. 7424:J 7420:g 7406:0 7403:= 7400:) 7392:g 7387:( 7381:= 7378:) 7375:) 7365:m 7361:y 7355:( 7349:, 7343:, 7340:) 7330:1 7326:y 7320:( 7314:( 7311:g 7308:= 7303:a 7292:g 7270:a 7255:J 7251:g 7247:Y 7231:a 7207:Y 7203:X 7192:. 7186:A 7182:Y 7153:. 7119:f 7115:y 7113:( 7111:f 7107:k 7103:f 7096:f 7080:X 7074:O 7062:f 7034:) 7031:L 7028:( 7019:) 7016:f 7013:( 7004:= 7001:) 6998:L 6989:f 6985:( 6966:q 6950:X 6944:O 6932:f 6926:q 6922:R 6899:n 6892:L 6883:X 6877:O 6865:f 6859:q 6855:R 6851:= 6848:) 6845:F 6836:f 6832:( 6823:f 6817:q 6813:R 6790:n 6783:L 6772:F 6755:. 6752:) 6749:F 6740:f 6730:f 6724:q 6720:R 6716:( 6708:q 6704:) 6700:1 6694:( 6684:0 6681:= 6678:q 6670:= 6667:) 6664:F 6655:f 6651:( 6625:) 6622:F 6613:f 6609:, 6606:X 6603:( 6595:q 6592:+ 6589:p 6585:H 6578:) 6575:F 6566:f 6556:f 6550:q 6546:R 6542:, 6539:Y 6536:( 6528:p 6524:H 6510:Y 6506:F 6498:Y 6494:X 6490:f 6466:. 6463:) 6460:F 6457:( 6451:) 6448:f 6445:( 6436:= 6433:) 6430:F 6421:f 6417:( 6397:Y 6393:F 6382:Y 6378:X 6370:f 6363:f 6356:U 6350:Y 6346:O 6341:) 6339:U 6337:( 6335:f 6329:X 6325:O 6321:Y 6317:U 6309:Y 6307:( 6305:k 6302:f 6298:X 6296:( 6294:k 6290:f 6286:k 6278:Y 6274:X 6270:f 6248:f 6215:} 6212:n 6206:) 6203:x 6200:( 6197:e 6191:X 6185:x 6182:{ 6179:= 6174:n 6170:X 6156:n 6148:e 6131:. 6128:} 6125:x 6117:) 6114:) 6111:x 6108:( 6105:f 6102:( 6097:1 6090:f 6081:Z 6075:Z 6066:{ 6060:= 6057:) 6054:x 6051:( 6048:e 6035:X 6031:x 6027:Y 6023:X 6019:f 5992:. 5989:r 5986:+ 5983:W 5974:= 5971:Z 5943:) 5940:U 5937:( 5932:1 5925:f 5904:) 5901:W 5898:( 5893:1 5886:f 5875:Z 5871:U 5867:Y 5863:W 5849:) 5846:X 5843:( 5840:f 5834:U 5824:Y 5820:U 5802:. 5799:r 5796:+ 5793:W 5781:Z 5763:W 5749:) 5746:W 5743:( 5738:1 5731:f 5720:Z 5716:Y 5712:W 5704:Y 5700:X 5696:r 5692:Y 5688:X 5684:f 5650:1 5645:P 5637:X 5634:: 5631:f 5611:) 5608:z 5605:: 5602:y 5599:( 5596:= 5593:) 5590:z 5587:x 5584:: 5581:y 5578:x 5575:( 5572:= 5569:) 5564:2 5560:y 5556:: 5553:y 5550:x 5547:( 5544:= 5541:) 5538:y 5535:: 5532:x 5529:( 5519:X 5505:} 5502:0 5496:z 5493:, 5490:0 5484:x 5478:X 5472:) 5469:z 5466:: 5463:y 5460:: 5457:x 5454:( 5451:{ 5431:) 5428:z 5425:: 5422:y 5419:( 5413:) 5410:z 5407:: 5404:y 5401:: 5398:x 5395:( 5375:) 5372:y 5369:: 5366:x 5363:( 5357:) 5354:z 5351:: 5348:y 5345:: 5342:x 5339:( 5329:P 5315:z 5312:x 5309:= 5304:2 5300:y 5289:X 5264:X 5251:i 5247:f 5228:X 5216:X 5206:x 5201:i 5197:f 5193:X 5189:x 5185:x 5180:i 5176:f 5172:X 5168:x 5164:U 5160:x 5143:) 5140:) 5137:x 5134:( 5129:m 5125:f 5121:: 5115:: 5112:) 5109:x 5106:( 5101:1 5097:f 5093:: 5090:) 5087:x 5084:( 5079:0 5075:f 5071:( 5068:= 5065:) 5062:x 5059:( 5056:f 5043:k 5038:i 5034:f 5030:0 5027:f 5025:/ 5022:i 5018:f 5013:i 5009:g 5005:0 5002:f 4998:X 4994:k 4989:i 4985:g 4981:X 4977:U 4972:i 4968:g 4951:) 4948:) 4945:x 4942:( 4937:m 4933:g 4929:, 4923:, 4920:) 4917:x 4914:( 4909:1 4905:g 4901:( 4898:= 4895:) 4892:x 4889:( 4884:U 4879:| 4874:f 4860:U 4857:| 4855:f 4841:) 4836:0 4832:a 4827:/ 4821:m 4817:a 4813:, 4807:, 4802:0 4798:a 4793:/ 4787:1 4783:a 4779:( 4773:) 4768:0 4764:a 4759:/ 4753:m 4749:a 4745:: 4739:: 4734:0 4730:a 4725:/ 4719:1 4715:a 4711:: 4708:1 4705:( 4702:= 4699:) 4694:m 4690:a 4686:: 4680:: 4675:0 4671:a 4667:( 4657:A 4652:i 4648:y 4631:} 4628:0 4625:= 4620:0 4616:y 4612:{ 4604:m 4599:P 4591:U 4588:: 4585:f 4572:x 4568:U 4564:i 4560:x 4558:( 4556:f 4552:i 4548:X 4544:x 4521:m 4516:P 4508:X 4505:: 4502:f 4458:f 4450:f 4446:f 4430:p 4426:t 4419:t 4381:X 4377:P 4373:X 4369:X 4365:X 4361:P 4357:X 4353:f 4349:P 4345:X 4341:f 4337:P 4333:X 4326:k 4322:k 4318:Y 4314:X 4296:) 4293:X 4290:( 4287:k 4281:) 4278:Y 4275:( 4272:k 4262:X 4258:Y 4246:Y 4225:f 4219:g 4213:g 4209:, 4206:) 4203:X 4200:( 4197:k 4191:] 4188:V 4185:[ 4182:k 4166:= 4163:) 4160:Y 4157:( 4154:k 4141:f 4127:] 4124:U 4121:[ 4118:k 4112:] 4109:V 4106:[ 4103:k 4100:: 4091:f 4080:V 4076:U 4074:( 4072:f 4068:X 4064:U 4060:Y 4056:V 4052:f 4044:Y 4042:→ 4040:X 4038:: 4036:f 4021:f 4017:f 4003:) 4000:y 3997:x 3994:, 3991:x 3988:( 3982:) 3979:y 3976:, 3973:x 3970:( 3966:, 3961:2 3956:A 3946:2 3941:A 3915:. 3903:) 3900:x 3897:( 3894:f 3891:= 3888:) 3885:) 3882:y 3879:, 3876:x 3873:( 3870:p 3867:( 3864:f 3861:= 3858:) 3855:y 3852:, 3849:x 3846:( 3843:) 3840:1 3834:f 3831:( 3811:1 3805:f 3799:f 3795:, 3792:] 3789:Y 3786:[ 3783:k 3778:k 3770:] 3767:X 3764:[ 3761:k 3758:= 3755:] 3752:Y 3746:X 3743:[ 3740:k 3734:] 3731:X 3728:[ 3725:k 3722:: 3713:p 3702:Y 3698:X 3684:x 3678:) 3675:y 3672:, 3669:x 3666:( 3662:, 3659:X 3653:Y 3647:X 3644:: 3641:p 3631:Y 3627:X 3622:. 3620:V 3616:F 3612:F 3600:k 3592:V 3588:F 3584:V 3574:V 3572:( 3570:k 3560:z 3556:f 3552:f 3538:) 3535:z 3531:/ 3527:1 3524:( 3521:f 3518:= 3515:) 3512:f 3509:( 3489:P 3485:f 3481:P 3477:A 3473:x 3469:x 3455:} 3449:{ 3441:1 3436:A 3431:= 3426:1 3421:P 3406:A 3402:X 3398:X 3394:X 3390:k 3386:X 3382:f 3378:x 3374:g 3370:k 3366:h 3362:g 3344:m 3340:y 3336:h 3331:= 3324:n 3320:x 3316:g 3311:= 3308:f 3288:] 3283:1 3276:y 3272:, 3269:y 3266:, 3263:x 3260:[ 3257:k 3237:] 3234:y 3231:, 3226:1 3219:x 3215:, 3212:x 3209:[ 3206:k 3203:= 3200:] 3195:1 3188:x 3184:[ 3181:] 3176:2 3171:A 3166:[ 3163:k 3160:= 3157:] 3154:) 3151:x 3148:( 3141:2 3136:A 3130:D 3126:[ 3123:k 3103:} 3100:0 3097:= 3094:x 3091:{ 3083:2 3078:A 3073:= 3070:) 3067:x 3064:( 3057:2 3052:A 3046:D 3035:f 3031:X 3027:f 3023:X 3017:A 3013:X 3007:. 2992:y 2989:+ 2986:1 2982:x 2977:= 2974:) 2971:y 2968:, 2965:x 2962:( 2959:f 2949:f 2945:X 2941:X 2937:f 2923:. 2918:x 2914:y 2908:1 2902:= 2899:) 2896:y 2893:, 2890:x 2887:( 2884:f 2874:y 2870:x 2866:X 2858:U 2855:| 2853:f 2839:] 2834:1 2827:) 2823:1 2817:t 2814:( 2811:, 2808:t 2805:[ 2802:k 2796:] 2793:t 2785:3 2781:t 2777:, 2774:1 2766:2 2762:t 2758:[ 2755:k 2752:= 2749:] 2746:X 2743:[ 2740:k 2720:X 2714:U 2711:: 2708:f 2698:U 2694:t 2690:U 2686:A 2682:U 2675:f 2661:, 2658:) 2655:t 2647:3 2643:t 2639:, 2636:1 2628:2 2624:t 2620:( 2617:g 2611:g 2607:, 2604:] 2601:t 2598:[ 2595:k 2589:] 2586:X 2583:[ 2580:k 2577:: 2568:f 2547:) 2544:t 2536:3 2532:t 2528:, 2525:1 2517:2 2513:t 2509:( 2503:t 2499:, 2496:X 2488:1 2483:A 2478:: 2475:f 2453:2 2449:x 2445:+ 2440:3 2436:x 2432:= 2427:2 2423:y 2412:X 2405:f 2401:g 2387:) 2382:2 2378:x 2374:, 2371:x 2368:( 2365:= 2362:) 2359:x 2356:( 2353:g 2333:x 2327:) 2324:y 2321:, 2318:x 2315:( 2311:, 2306:1 2301:A 2293:X 2290:: 2287:f 2265:2 2261:x 2257:= 2254:y 2244:X 2237:P 2233:n 2229:A 2204:k 2200:k 2179:} 2176:0 2173:= 2170:) 2167:x 2164:( 2161:g 2155:] 2152:X 2149:[ 2146:k 2140:g 2137:{ 2134:= 2129:x 2123:m 2110:x 2108:( 2106:f 2102:x 2082:) 2079:x 2076:( 2073:f 2067:m 2061:, 2056:x 2050:m 2024:) 2019:x 2013:m 2007:( 2002:1 1991:= 1986:) 1983:x 1980:( 1977:f 1971:m 1939:f 1935:= 1921:Y 1917:X 1913:f 1904:k 1893:B 1889:A 1885:Y 1881:X 1849:) 1844:p 1839:( 1834:1 1818:p 1812:, 1809:Y 1803:X 1800:: 1795:a 1776:A 1772:B 1762:B 1758:Y 1754:A 1750:X 1738:x 1734:h 1730:h 1728:/ 1726:g 1722:f 1708:] 1700:X 1695:[ 1692:k 1682:h 1678:g 1674:x 1670:X 1666:f 1643:X 1621:] 1613:X 1608:[ 1605:k 1595:h 1591:g 1587:h 1585:/ 1583:g 1579:X 1575:X 1556:X 1544:X 1542:( 1540:k 1532:X 1521:h 1517:g 1513:h 1509:g 1505:x 1501:h 1497:h 1495:/ 1493:g 1489:f 1485:x 1481:h 1477:g 1473:x 1465:x 1461:x 1457:A 1455:→ 1453:X 1451:: 1449:f 1414:A 1412:→ 1410:X 1408:: 1406:f 1402:A 1398:Y 1382:X 1378:Y 1374:f 1370:f 1366:Y 1362:X 1355:f 1351:f 1337:. 1334:f 1331:= 1326:a 1315:f 1289:= 1277:a 1248:i 1244:y 1221:i 1212:y 1186:) 1183:) 1173:m 1169:y 1163:( 1157:, 1151:, 1148:) 1138:1 1134:y 1128:( 1122:( 1119:= 1114:a 1087:, 1084:J 1080:/ 1076:] 1071:m 1067:y 1063:, 1057:, 1052:1 1048:y 1044:[ 1041:k 1038:= 1035:] 1032:Y 1029:[ 1026:k 1003:Y 997:X 994:: 989:a 961:] 958:X 955:[ 952:k 946:] 943:Y 940:[ 937:k 934:: 911:] 908:X 905:[ 902:k 882:) 877:m 873:f 869:, 863:, 858:1 854:f 850:( 847:g 844:= 841:f 835:g 825:Y 821:X 807:] 804:Y 801:[ 798:k 795:, 792:] 789:X 786:[ 783:k 760:f 754:g 748:g 744:, 741:] 738:X 735:[ 732:k 726:] 723:Y 720:[ 717:k 714:: 705:f 691:Y 689:→ 687:X 685:: 683:f 659:Y 657:→ 655:X 653:: 651:f 647:Y 643:X 632:X 624:f 620:V 616:U 612:V 610:→ 608:U 606:: 604:f 600:V 596:U 594:( 592:f 588:x 586:( 584:f 580:V 576:x 572:U 568:x 557:Y 555:→ 553:X 551:: 549:f 532:Y 512:Y 506:X 503:: 500:f 490:Y 486:Y 482:X 480:( 478:f 474:I 470:g 466:f 462:X 458:g 454:f 450:X 442:I 425:, 422:I 418:/ 414:] 409:n 405:x 401:, 395:, 390:1 386:x 382:[ 379:k 376:= 373:] 370:X 367:[ 364:k 351:X 331:i 327:f 303:) 298:m 294:f 290:, 284:, 279:1 275:f 271:( 268:= 265:f 240:m 235:A 225:n 220:A 195:Y 189:X 183:f 157:m 152:A 128:n 123:A 107:Y 103:X 31:. 20:)

Index

Dominant morphism
Biregular graph
algebraic geometry
algebraic varieties
polynomials
affine line
isomorphisms
projective varieties
rational
birational
partial functions
rational fractions
locally ringed space
subvarieties
affine varieties
polynomial map
coordinate ring
ideal
varieties
ringed space
category of algebraic varieties
algebra homomorphisms
#Examples
smooth functions
ring of regular functions
coordinate ring
projective variety
Liouville's theorem
complex analysis
rational function

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