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Affine variety

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The affine scheme has "classical points", which correspond with points of the variety (and hence maximal ideals of the coordinate ring of the variety), and also a point for each closed subvariety of the variety (these points correspond to prime, non-maximal ideals of the coordinate ring). This
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If an author requires the base field of an affine variety to be algebraically closed (as this article does), then irreducible affine algebraic sets over non-algebraically closed fields are a generalization of affine varieties. This generalization notably includes affine varieties over the
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If the point is singular, the affine subspace defined by these equations is also called a tangent space by some authors, while other authors say that there is no tangent space at a singular point. A more intrinsic definition, which does not use coordinates is given by
3762: 3320:, is the inverse of the function assigning an algebraic set to a radical ideal, by the nullstellensatz. Hence the correspondence between affine algebraic sets and radical ideals is a bijection. The coordinate ring of an affine algebraic set is 6616:
creates a more well-defined notion of the "generic point" of an affine variety, by assigning to each closed subvariety an open point that is dense in the subvariety. More generally, an affine scheme is an affine variety if it is
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is not prime. Affine subvarieties are precisely those whose coordinate ring is an integral domain. This is because an ideal is prime if and only if the quotient of the ring by the ideal is an integral domain.
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between the coordinate rings (going in the opposite direction), and for each such homomorphism, there is a morphism of the varieties associated to the coordinate rings. This can be shown explicitly: let
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Similarly, for each homomorphism of the coordinate rings, a morphism of the affine varieties can be constructed in the opposite direction. Mirroring the paragraph above, a homomorphism
6027:.) This makes the cohomological study of an affine variety non-existent, in a sharp contrast to the projective case in which cohomology groups of line bundles are of central interest. 4891: 3811: 5552: 1972: 5918: 2030: 5364: 4750: 3207: 2670: 2605: 4784: 3298: 374: 5856: 5185: 5039: 3484: 3416: 948: 1143: 2541: 1067: 91: 1413: 910: 3513: 5984: 3858: 3251: 5600: 3066: 2504: 5620: 5465: 2814: 6010: 2247: 1199: 982: 716: 4263:
A morphism, or regular map, of affine varieties is a function between affine varieties that is polynomial in each coordinate: more precisely, for affine varieties
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are obtained by gluing affine varieties. Linear structures that are attached to varieties are also (trivially) affine varieties; e.g., tangent spaces, fibers of
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is an integer associated to every variety, and even to every algebraic set, whose importance relies on the large number of its equivalent definitions (see
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As maximal ideals are radical, maximal ideals correspond to minimal algebraic sets (those that contain no proper algebraic subsets), which are points in
609:{\displaystyle V(f_{1},\ldots ,f_{m})=\left\{(a_{1},\ldots ,a_{n})\in k^{n}\;|\;f_{1}(a_{1},\ldots ,a_{n})=\ldots =f_{m}(a_{1},\ldots ,a_{n})=0\right\}.} 3860:
An algebraic subset is a point if and only if the coordinate ring of the subset is a field, as the quotient of a ring by a maximal ideal is a field.
2072: 1666:-rational points; each such point is the second intersection point of the curve and a line with a rational slope passing through the rational point. 1453: 3863:
The following table summarises this correspondence, for algebraic subsets of an affine variety and ideals of the corresponding coordinate ring:
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going in the opposite direction. Because of this, along with the fact that there is a one-to-one correspondence between affine varieties over
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is an affine algebraic set that is not the union of two proper affine algebraic subsets. Such an affine algebraic set is often said to be
5044: 1787: 1269: 2420:{\displaystyle \sum _{i=1}^{n}{\frac {\partial f_{j}}{\partial {x_{i}}}}(a_{1},\dots ,a_{n})(x_{i}-a_{i})=0,\quad j=1,\dots ,r.} 1672: 1563: 6490: 3526: 6759: 2962:
The geometric structure of an affine variety is linked in a deep way to the algebraic structure of its coordinate ring. Let
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of the Zariski topologies on the two spaces. Indeed, the product topology is generated by products of the basic open sets
6725: 3757:{\displaystyle (a_{1},\ldots ,a_{n})\mapsto \langle {\overline {x_{1}-a_{1}}},\ldots ,{\overline {x_{n}-a_{n}}}\rangle ,} 5218: 6686:
This is because, over an algebraically closed field, the tensor product of integral domains is an integral domain; see
3088:. The reason that the base field is required to be algebraically closed is that affine varieties automatically satisfy 2823: 995:
of the coordinate ring of the variety. (Similarly, the normalization of a projective variety is a projective variety.)
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gives a cohomological characterization of an affine variety; it says an algebraic variety is affine if and only if
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There is a one-to-one correspondence between morphisms of affine varieties over an algebraically closed field
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The Red Book of Varieties and Schemes: Includes the Michigan Lectures (1974) on Curves and Their Jacobians
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The original article was written as a partial human translation of the corresponding French article.
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Using the multiplicative notation, the associativity, identity and inverse laws can be rewritten as:
1382: 226:) over which the common zeros are considered (that is, the points of the affine algebraic set are in 887: 3489: 288: 5941: 3820: 3230: 6547: 5569: 5555: 5203: 3047: 2464: 6441: 6036: 4447: 4415: 3339:
Prime ideals of the coordinate ring correspond to affine subvarieties. An affine algebraic set
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can be drawn on a piece of paper or by graphing software. The figure on the right shows the
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of an irreducible affine variety is affine; the coordinate ring of the normalization is the
6769: 6420: 6013: 4992: 2225: 1172: 960: 652: 8: 6539: 6283: 3069: 2924: 2672:(in fact, a countable intersection of affine algebraic sets is an affine algebraic set). 189: 3099: 2985: 125: 6876: 6780: 6560: 6543: 1641: 836: 105: 97: 5745:{\displaystyle {\mathcal {O}}_{X,x}=\varinjlim _{f(x)\neq 0}A=A_{{\mathfrak {m}}_{x}}} 6883: 6857: 6789: 6755: 6715: 6494: 6286:
on the variety. The above morphisms are often written using ordinary group notation:
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are exactly the hypersurfaces, that is the varieties defined by a single polynomial.
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an algebraic set whose defining ideal is prime (affine variety in the above sense).
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It can be shown that any affine algebraic group is isomorphic to a subgroup of
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is finitely-generated, so every open set is a finite union of basic open sets.
2153:{\displaystyle {\frac {\partial f_{j}}{\partial {x_{i}}}}(a_{1},\dots ,a_{n}).} 1031: 218:
in which the coefficients are considered, from the algebraically closed field
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is precisely the category of finitely-generated, nilpotent-free algebras over
6900: 6837: 6720: 6556: 6083: 1543:{\displaystyle \left({\frac {1-t^{2}}{1+t^{2}}},{\frac {2t}{1+t^{2}}}\right)} 988: 647: 6431: 3321: 4991:
Equipped with the structure sheaf described below, an affine variety is a
30: 6530: 1438: 1220: 950:(the affine plane with the origin removed) is not an affine variety; cf. 264: 193: 6871: 3343:
can be written as the union of two other algebraic sets if and only if
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is simply the subspace topology inherited from the Zariski topology on
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asserts that the affine algebraic variety (it is a curve) defined by
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is a sheaf; indeed, it says if a function is regular (pointwise) on
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A product of affine varieties can be defined using the isomorphism
2679:, where Zariski-open sets are countable unions of sets of the form 1866:{\displaystyle V(y^{2}-x^{3}+x^{2}+16x)\subseteq \mathbf {C} ^{2}.} 4440:
and their coordinate rings, the category of affine varieties over
6567:). Each affine variety has an affine scheme associated to it: if 769:), it is the space of global sections of the structure sheaf of 6844:. Lecture Notes in Mathematics. Vol. 1358 (2nd ed.). 4563:
be a morphism. Indeed, a homomorphism between polynomial rings
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and homomorphisms of coordinate rings of affine varieties over
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will define algebraic sets that are in the Zariski topology on
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It can be proved that an algebraic curve of degree two with a
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to the category of coordinate rings of affine varieties over
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The most prominent example of an affine algebraic group is
3308:. Furthermore, the function taking an affine algebraic set 4457:
The category of coordinate rings of affine varieties over
1732:{\displaystyle V(x^{2}+y^{2}+1)\subseteq \mathbf {C} ^{2}} 1623:{\displaystyle V(x^{2}+y^{2}-3)\subseteq \mathbf {C} ^{2}} 3934:
then embedding the product in this new affine space. Let
1640:-rational point. This can be deduced from the fact that, 324:
of a system of polynomial equations with coefficients in
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is the set of solutions in an algebraically closed field
3620:{\displaystyle R=k/\langle f_{1},\ldots ,f_{m}\rangle ,} 957:
The subvarieties of codimension one in the affine space
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Proof: The inclusion ⊃ is clear. For the opposite, let
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but cannot be obtained as a product of a polynomial in
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Affine algebraic groups play an important role in the
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Radical ideals (ideals that are their own radical) of
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The complement of a hypersurface in an affine variety
6508:-rational points of an affine algebraic group, where 5992: 5944: 5883: 5833: 5820:{\displaystyle {\mathfrak {m}}_{x}=\{f\in A|f(x)=0\}} 5761: 5637: 5608: 5572: 5496: 5404: 5317: 5221: 5162: 5047: 5016: 4837: 4758: 4721: 3823: 3770: 3633: 3627:
this correspondence becomes explicit through the map
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The Zariski topology can also be described by way of
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An affine variety plays a role of a local chart for
5874:); that is, "regular-ness" can be patched together. 1875: 912:(the affine line with the origin removed) is affine. 816:) is affine. Its defining equations are obtained by 6559:, a locally-ringed space that is isomorphic to the 6430:This is the group of linear transformations of the 4643:corresponds uniquely to a choice of image for each 6875: 6004: 5978: 5912: 5850: 5819: 5744: 5614: 5594: 5546: 5459: 5358: 5288:{\displaystyle \Gamma (D(f),{\mathcal {O}}_{X})=A} 5287: 5179: 5105: 5033: 4885: 4778: 4744: 3852: 3805: 3756: 3619: 3507: 3478: 3410: 3292: 3245: 3201: 3146: 3060: 3032: 2957: 2903: 2808: 2744: 2664: 2599: 2535: 2498: 2419: 2241: 2152: 2024: 1966: 1865: 1731: 1622: 1542: 1407: 1337: 1193: 1137: 1061: 976: 942: 904: 873: 710: 608: 368: 172: 85: 2904:{\displaystyle V(f)=D_{f}=\{p\in k^{n}:f(p)=0\},} 642:is the ideal of all polynomials that are zero on 6898: 5923: 4899:. This corresponds to the morphism of varieties 4252: 1884:be an affine variety defined by the polynomials 1351:and all its coordinates are integers. The point 1201:Often, if the base field is the complex numbers 27:Algebraic variety defined within an affine space 6082:, which is a regular morphism that follows the 3914: 2745:{\displaystyle U_{f}=\{p\in k^{n}:f(p)\neq 0\}} 1745:-rational points, but has many complex points. 239:, and the points of the variety that belong to 6451:is fixed, this is equivalent to the group of 5866:), then it must be in the coordinate ring of 5197:sheaf of modules#Sheaf associated to a module 5187:is determined by its values on the open sets 4486:of affine varieties, there is a homomorphism 2816:These basic open sets are the complements in 5814: 5779: 5541: 5512: 5353: 5324: 3748: 3672: 3611: 3579: 3332:is radical if and only if the quotient ring 2895: 2855: 2739: 2699: 6754:, vol. 52, New York: Springer-Verlag, 2974:, the coordinate ring of an affine variety 188:, is an affine algebraic set such that the 6740: 6555:An affine variety is a special case of an 6030: 4521:be affine varieties with coordinate rings 3813:denotes the image in the quotient algebra 3523:is an affine variety with coordinate ring 2066:is the matrix of the partial derivatives 1660:-rational point has infinitely many other 1008:A drawing of the real points of the curve 492: 486: 5386:, there is some open affine neighborhood 4886:{\displaystyle f_{i}(X_{1},\dots ,X_{n})} 3806:{\displaystyle {\overline {x_{i}-a_{i}}}} 924: 892: 214:), it is useful to distinguish the field 192:generated by the defining polynomials is 5547:{\displaystyle V(J)\subset \{x|f(x)=0\}} 5206:in the essential way, is the following: 4610:is determined uniquely by the images of 1967:{\displaystyle f_{1},\dots ,f_{r}\in k,} 1003: 29: 6836: 6699: 5152:. They form a base for the topology of 2438: 738:is prime, so the coordinate ring is an 382:, they define an affine algebraic set 302:has no rational points for any integer 14: 6899: 6775: 6645: 6491:classification of finite simple groups 5913:{\displaystyle (X,{\mathcal {O}}_{X})} 5624:The claim, first of all, implies that 2453:form the closed sets of a topology on 2025:{\displaystyle a=(a_{1},\dots ,a_{n})} 1447:-rational points that are the points 1163:-rational points of an affine variety 742:. The elements of the coordinate ring 6802: 6662: 2911:zero loci of a single polynomial. If 376:are polynomials with coefficients in 283:is a point that is rational over the 232:). In this case, the variety is said 6870: 6674: 6651: 6461:invertible matrices with entries in 5359:{\displaystyle J=\{h\in A|hg\in A\}} 4745:{\displaystyle {\overline {f_{i}}},} 3958:respectively, so that their product 3202:{\displaystyle I(V(J))={\sqrt {J}}.} 2665:{\displaystyle V(S)\cap V(T)=V(S,T)} 2600:{\displaystyle V(S)\cup V(T)=V(ST),} 1427:-rational. This variety is called a 766: 210:In some contexts (see, for example, 6726:Representations on coordinate rings 6628:over an algebraically closed field 6047:over an algebraically closed field 5827:. Secondly, the claim implies that 5765: 5729: 4779:{\displaystyle {\overline {f_{i}}}} 4142:The product is irreducible if each 3418:). This is the case if and only if 3293:{\displaystyle V(J)\subseteq V(I).} 3215:correspond to algebraic subsets of 1647:, the sum of two squares cannot be 1069:over an algebraically closed field 369:{\displaystyle f_{1},\ldots ,f_{m}} 24: 6522: 5896: 5851:{\displaystyle {\mathcal {O}}_{X}} 5837: 5641: 5628:is a "locally ringed" space since 5246: 5222: 5180:{\displaystyle {\mathcal {O}}_{X}} 5166: 5089: 5074: 5051: 5034:{\displaystyle {\mathcal {O}}_{X}} 5020: 4986: 4690:a homomorphism can be constructed 4585:factors uniquely through the ring 4472:More precisely, for each morphism 3479:{\displaystyle V(J)\subseteq V(I)} 3411:{\displaystyle V(I)=V(J)\cup V(K)} 3158:is an algebraically closed field, 2527: 2461:. This follows from the fact that 2301: 2286: 2094: 2079: 1151:whose coordinates are elements of 999: 943:{\displaystyle \mathbb {C} ^{2}-0} 830:. The coordinate ring is thus the 25: 6918: 6594:then the scheme corresponding to 4249:but not in the product topology. 2982:be the set of all polynomials in 1876:Singular points and tangent space 1760:defined over the complex numbers 1138:{\displaystyle p\in V\cap k^{n}.} 782:Dimension of an algebraic variety 6878:Undergraduate Algebraic Geometry 6563:of a commutative ring (up to an 4088:is defined as the algebraic set 2536:{\displaystyle V(1)=\emptyset ,} 1850: 1719: 1610: 1322: 1062:{\displaystyle V\subseteq K^{n}} 761:on the variety, or, simply, the 636:is an affine algebraic set, and 86:{\displaystyle y^{2}=x^{2}(x+1)} 4259:Morphism of algebraic varieties 4220:Hence, polynomials that are in 2958:Geometry–algebra correspondence 2392: 1408:{\displaystyle (i,{\sqrt {2}})} 1266:-rational point of the variety 309: 6882:. Cambridge University Press. 6693: 6680: 6668: 6656: 5967: 5955: 5907: 5884: 5805: 5799: 5792: 5715: 5699: 5682: 5676: 5532: 5526: 5519: 5506: 5500: 5454: 5438: 5429: 5426: 5420: 5414: 5337: 5282: 5266: 5257: 5237: 5231: 5225: 5202:The key fact, which relies on 5100: 5077: 5068: 5062: 4880: 4848: 3669: 3666: 3634: 3571: 3539: 3473: 3467: 3458: 3452: 3405: 3399: 3390: 3384: 3375: 3369: 3324:(nilpotent-free), as an ideal 3284: 3278: 3269: 3263: 3183: 3180: 3174: 3168: 3138: 3106: 3024: 2992: 2886: 2880: 2836: 2830: 2800: 2768: 2730: 2724: 2659: 2647: 2638: 2632: 2623: 2617: 2591: 2582: 2573: 2567: 2558: 2552: 2521: 2515: 2477: 2471: 2380: 2354: 2351: 2319: 2144: 2112: 2019: 1987: 1958: 1926: 1842: 1794: 1711: 1679: 1602: 1570: 1402: 1386: 1314: 1282: 1185: 1179: 905:{\displaystyle \mathbb {C} -0} 868: 852: 849: 843: 754:on the variety. They form the 697: 665: 589: 557: 535: 503: 488: 470: 438: 427: 395: 164: 132: 80: 68: 13: 1: 6752:Graduate Texts in Mathematics 6731: 5930:Serre's theorem on affineness 5924:Serre's theorem on affineness 5311:be in the left-hand side and 4253:Morphisms of affine varieties 3508:{\displaystyle I\subseteq J.} 3219:. Indeed, for radical ideals 2449:The affine algebraic sets of 6831:Lectures on Étale cohomology 6702:, Ch. I, § 4. Proposition 1. 5979:{\displaystyle H^{i}(X,F)=0} 4786:is the equivalence class of 4771: 4734: 3915:Products of affine varieties 3853:{\displaystyle x_{i}-a_{i}.} 3798: 3743: 3702: 3246:{\displaystyle I\subseteq J} 300: − 1 = 0 271:-rational point is called a 7: 6709: 6608:the set of prime ideals of 5920:is a locally ringed space. 5595:{\displaystyle f^{n}g\in A} 3061:{\displaystyle {\sqrt {I}}} 2942:is an affine subvariety of 2499:{\displaystyle V(0)=k^{n},} 787: 734:is an affine variety, then 259:. In the common case where 203:for any algebraic set, and 10: 6923: 6688:integral domain#Properties 6034: 5927: 4654:. Then given any morphism 4256: 3997:be an algebraic subset of 2442: 1634:of degree two that has no 1243:) are often simply called 1029: 952:Hartogs' extension theorem 621:affine (algebraic) variety 110:algebraically closed field 6565:equivalence of categories 6282:Together, these define a 6086:axiom—that is, such that 4629:Hence, each homomorphism 3442:are radical ideals, then 3090:Hilbert's nullstellensatz 3076:, the set of polynomials 1441:. It has infinitely many 1431:, because the set of its 212:Hilbert's Nullstellensatz 104:is the set of the common 6638: 6573:is an affine variety in 6548:algebraic vector bundles 5615:{\displaystyle \square } 5460:{\displaystyle g\in k=A} 5366:, which is an ideal. If 4998:Given an affine variety 4157:The Zariski topology on 3875:Type of coordinate ring 3430:correspond to points of 3080:for which some power of 2946:the Zariski topology on 1754:is an affine variety in 1437:-rational points is the 199:Some texts use the term 186:affine algebraic variety 6484:linear algebraic groups 6031:Affine algebraic groups 5556:Hilbert nullstellensatz 5204:Hilbert nullstellensatz 4031:an algebraic subset of 3880:affine algebraic subset 2931:), then every ideal of 2809:{\displaystyle f\in k.} 6214:, a regular bijection 6055:affine algebraic group 6037:linear algebraic group 6006: 6005:{\displaystyle i>0} 5980: 5914: 5852: 5821: 5746: 5616: 5596: 5548: 5461: 5360: 5289: 5181: 5107: 5041:is defined by letting 5035: 4887: 4780: 4746: 3946:have coordinate rings 3854: 3807: 3758: 3621: 3509: 3480: 3412: 3294: 3247: 3203: 3148: 3062: 3034: 2929:principal ideal domain 2905: 2810: 2746: 2666: 2601: 2537: 2500: 2421: 2282: 2243: 2154: 2026: 1968: 1867: 1733: 1624: 1557:is a rational number. 1544: 1409: 1339: 1195: 1139: 1063: 1036:For an affine variety 1027: 978: 944: 906: 875: 824:the defining ideal of 778:dimension of a variety 765:; in other words (see 712: 610: 370: 174: 93: 87: 6579:with coordinate ring 6007: 5981: 5915: 5853: 5822: 5747: 5617: 5597: 5562:is in the radical of 5549: 5462: 5361: 5290: 5182: 5108: 5036: 5002:with coordinate ring 4888: 4781: 4747: 4418:of affine varieties. 4232:with a polynomial in 3869:Type of algebraic set 3855: 3808: 3759: 3622: 3510: 3481: 3413: 3295: 3248: 3204: 3149: 3063: 3035: 2906: 2811: 2747: 2667: 2602: 2538: 2501: 2433:Zariski tangent space 2422: 2262: 2244: 2242:{\displaystyle k^{n}} 2155: 2027: 1969: 1868: 1734: 1625: 1545: 1410: 1340: 1196: 1194:{\displaystyle V(k).} 1140: 1064: 1007: 979: 977:{\displaystyle k^{n}} 945: 907: 876: 713: 711:{\displaystyle R=k/I} 611: 371: 330:. More precisely, if 289:Fermat's Last Theorem 175: 88: 33: 6808:"Algebraic Geometry" 6544:projective varieties 6421:general linear group 6014:quasi-coherent sheaf 5990: 5942: 5881: 5831: 5759: 5635: 5606: 5570: 5494: 5402: 5315: 5219: 5160: 5045: 5014: 4993:locally ringed space 4835: 4756: 4719: 3964:has coordinate ring 3821: 3768: 3631: 3527: 3490: 3446: 3363: 3257: 3231: 3162: 3100: 3048: 2986: 2824: 2756: 2683: 2611: 2546: 2509: 2465: 2439:The Zariski topology 2259: 2226: 2073: 1978: 1888: 1788: 1784:-rational points of 1772:-rational points of 1673: 1669:The complex variety 1630:is an example of an 1564: 1454: 1383: 1270: 1227:of the variety, and 1173: 1157:. The collection of 1145:That is, a point of 1107: 1040: 961: 919: 888: 837: 810:for some polynomial 752:polynomial functions 746:are also called the 653: 389: 334: 316:affine algebraic set 279:is not specified, a 126: 102:affine algebraic set 42: 18:Affine algebraic set 6540:algebraic varieties 6519:is a finite field. 5490:). In other words, 5214: —  4592:and a homomorphism 4170:topological product 4049:is a polynomial in 2820:of the closed sets 1369:is a real point of 915:On the other hand, 763:ring of the variety 205:irreducible variety 6907:Algebraic geometry 6788:. Addison-Wesley. 6747:Algebraic Geometry 6495:groups of Lie type 6339:can be written as 6301:can be written as 6041:An affine variety 6025:Cartan's theorem B 6002: 5976: 5910: 5848: 5817: 5742: 5692: 5670: 5612: 5592: 5544: 5457: 5356: 5285: 5212: 5177: 5103: 5031: 4883: 4776: 4742: 4549:respectively. Let 3850: 3817:of the polynomial 3803: 3754: 3617: 3505: 3476: 3426:Maximal ideals of 3408: 3347:for proper ideals 3290: 3243: 3199: 3147:{\displaystyle k,} 3144: 3058: 3033:{\displaystyle k,} 3030: 2919:(for instance, if 2901: 2806: 2742: 2662: 2597: 2533: 2496: 2417: 2239: 2150: 2022: 1964: 1863: 1729: 1620: 1540: 1405: 1335: 1233:-rational points ( 1207:, points that are 1191: 1135: 1059: 1028: 974: 940: 902: 871: 708: 606: 366: 306:greater than two. 173:{\displaystyle k.} 170: 115:of some family of 98:algebraic geometry 94: 83: 6761:978-0-387-90244-9 6742:Hartshorne, Robin 6716:Algebraic variety 5663: 5661: 5210: 5144:) ≠ 0 } for each 5115:regular functions 4774: 4737: 3912: 3911: 3891:affine subvariety 3801: 3746: 3705: 3194: 3056: 2317: 2110: 1533: 1500: 1400: 1260:-rational and an 1213:-rational (where 1169:is often denoted 1075:, and a subfield 874:{\displaystyle k} 758:regular functions 748:regular functions 275:. When the field 36:cubic plane curve 16:(Redirected from 6914: 6893: 6881: 6867: 6828:Milne, James S. 6825: 6823: 6821: 6812: 6799: 6787: 6782:Algebraic Curves 6772: 6703: 6697: 6691: 6684: 6678: 6672: 6666: 6660: 6654: 6649: 6634: 6614: 6607: 6599: 6593: 6578: 6572: 6518: 6507: 6497:are all sets of 6481: 6467: 6460: 6450: 6439: 6429: 6418: 6401: 6384: 6370: 6352: 6345: 6338: 6327: 6321: 6310: 6300: 6278: 6271: 6265: 6227: 6212:inverse morphism 6207: 6200: 6194: 6164: 6158:identity element 6153: 6146: 6140: 6134: 6128: 6081: 6052: 6046: 6011: 6009: 6008: 6003: 5985: 5983: 5982: 5977: 5954: 5953: 5936:theorem of Serre 5919: 5917: 5916: 5911: 5906: 5905: 5900: 5899: 5857: 5855: 5854: 5849: 5847: 5846: 5841: 5840: 5826: 5824: 5823: 5818: 5795: 5775: 5774: 5769: 5768: 5751: 5749: 5748: 5743: 5741: 5740: 5739: 5738: 5733: 5732: 5714: 5713: 5691: 5671: 5657: 5656: 5645: 5644: 5621: 5619: 5618: 5613: 5601: 5599: 5598: 5593: 5582: 5581: 5553: 5551: 5550: 5545: 5522: 5466: 5464: 5463: 5458: 5453: 5452: 5382:is regular near 5365: 5363: 5362: 5357: 5340: 5294: 5292: 5291: 5286: 5281: 5280: 5256: 5255: 5250: 5249: 5215: 5186: 5184: 5183: 5178: 5176: 5175: 5170: 5169: 5112: 5110: 5109: 5104: 5099: 5098: 5093: 5092: 5061: 5060: 5055: 5054: 5040: 5038: 5037: 5032: 5030: 5029: 5024: 5023: 4983: 4912: 4898: 4892: 4890: 4889: 4884: 4879: 4878: 4860: 4859: 4847: 4846: 4831:to a polynomial 4830: 4819: 4803: 4796: 4785: 4783: 4782: 4777: 4775: 4770: 4769: 4760: 4751: 4749: 4748: 4743: 4738: 4733: 4732: 4723: 4714: 4703: 4689: 4682: 4676: 4653: 4642: 4628: 4609: 4591: 4584: 4562: 4548: 4534: 4520: 4510: 4499: 4485: 4469: 4462: 4456: 4445: 4439: 4433: 4427: 4409: 4398: 4383: 4312: 4298: 4292: 4282: 4272: 4248: 4237: 4231: 4225: 4219: 4195: 4167: 4154:is irreducible. 4153: 4147: 4141: 4134: 4087: 4081: 4071: 4065: 4054: 4048: 4037: 4030: 4003: 3996: 3969: 3963: 3957: 3951: 3945: 3939: 3933: 3897:integral domain 3866: 3865: 3859: 3857: 3856: 3851: 3846: 3845: 3833: 3832: 3812: 3810: 3809: 3804: 3802: 3797: 3796: 3795: 3783: 3782: 3772: 3763: 3761: 3760: 3755: 3747: 3742: 3741: 3740: 3728: 3727: 3717: 3706: 3701: 3700: 3699: 3687: 3686: 3676: 3665: 3664: 3646: 3645: 3626: 3624: 3623: 3618: 3610: 3609: 3591: 3590: 3578: 3570: 3569: 3551: 3550: 3514: 3512: 3511: 3506: 3485: 3483: 3482: 3477: 3417: 3415: 3414: 3409: 3299: 3297: 3296: 3291: 3252: 3250: 3249: 3244: 3208: 3206: 3205: 3200: 3195: 3190: 3153: 3151: 3150: 3145: 3137: 3136: 3118: 3117: 3067: 3065: 3064: 3059: 3057: 3052: 3039: 3037: 3036: 3031: 3023: 3022: 3004: 3003: 2910: 2908: 2907: 2902: 2873: 2872: 2851: 2850: 2815: 2813: 2812: 2807: 2799: 2798: 2780: 2779: 2751: 2749: 2748: 2743: 2717: 2716: 2695: 2694: 2671: 2669: 2668: 2663: 2606: 2604: 2603: 2598: 2542: 2540: 2539: 2534: 2505: 2503: 2502: 2497: 2492: 2491: 2459:Zariski topology 2445:Zariski topology 2426: 2424: 2423: 2418: 2379: 2378: 2366: 2365: 2350: 2349: 2331: 2330: 2318: 2316: 2315: 2314: 2313: 2299: 2298: 2297: 2284: 2281: 2276: 2251:linear equations 2248: 2246: 2245: 2240: 2238: 2237: 2217: 2213: 2206:is regular, the 2205: 2194: 2186: 2166: 2159: 2157: 2156: 2151: 2143: 2142: 2124: 2123: 2111: 2109: 2108: 2107: 2106: 2092: 2091: 2090: 2077: 2065: 2061: 2057: 2035: 2031: 2029: 2028: 2023: 2018: 2017: 1999: 1998: 1973: 1971: 1970: 1965: 1957: 1956: 1938: 1937: 1919: 1918: 1900: 1899: 1883: 1872: 1870: 1869: 1864: 1859: 1858: 1853: 1832: 1831: 1819: 1818: 1806: 1805: 1783: 1777: 1771: 1765: 1759: 1753: 1744: 1738: 1736: 1735: 1730: 1728: 1727: 1722: 1704: 1703: 1691: 1690: 1665: 1659: 1650: 1646: 1639: 1629: 1627: 1626: 1621: 1619: 1618: 1613: 1595: 1594: 1582: 1581: 1556: 1549: 1547: 1546: 1541: 1539: 1535: 1534: 1532: 1531: 1530: 1514: 1506: 1501: 1499: 1498: 1497: 1481: 1480: 1479: 1463: 1446: 1436: 1426: 1420: 1414: 1412: 1411: 1406: 1401: 1396: 1379:-rational, and 1378: 1372: 1368: 1366: 1365: 1359: 1358: 1350: 1344: 1342: 1341: 1336: 1331: 1330: 1325: 1307: 1306: 1294: 1293: 1265: 1259: 1253: 1241:rational numbers 1238: 1232: 1218: 1212: 1206: 1200: 1198: 1197: 1192: 1168: 1162: 1156: 1150: 1144: 1142: 1141: 1136: 1131: 1130: 1102: 1092: 1086: 1080: 1074: 1068: 1066: 1065: 1060: 1058: 1057: 1026: 993:integral closure 983: 981: 980: 975: 973: 972: 949: 947: 946: 941: 933: 932: 927: 911: 909: 908: 903: 895: 884:In particular, 880: 878: 877: 872: 867: 866: 829: 823: 815: 809: 798: 767:#Structure sheaf 724: 723: 717: 715: 714: 709: 704: 696: 695: 677: 676: 645: 641: 635: 615: 613: 612: 607: 602: 598: 588: 587: 569: 568: 556: 555: 534: 533: 515: 514: 502: 501: 491: 485: 484: 469: 468: 450: 449: 426: 425: 407: 406: 381: 375: 373: 372: 367: 365: 364: 346: 345: 329: 323: 305: 301: 285:rational numbers 278: 270: 263:is the field of 262: 258: 249: 244: 238: 231: 225: 221: 217: 179: 177: 176: 171: 163: 162: 144: 143: 114: 92: 90: 89: 84: 67: 66: 54: 53: 21: 6922: 6921: 6917: 6916: 6915: 6913: 6912: 6911: 6897: 6896: 6890: 6864: 6846:Springer-Verlag 6819: 6817: 6810: 6804:Milne, James S. 6796: 6785: 6777:Fulton, William 6762: 6734: 6712: 6707: 6706: 6698: 6694: 6685: 6681: 6673: 6669: 6661: 6657: 6650: 6646: 6641: 6629: 6609: 6601: 6595: 6580: 6574: 6568: 6525: 6523:Generalizations 6517: 6509: 6506: 6498: 6475: 6469: 6462: 6452: 6445: 6434: 6424: 6412: 6406: 6386: 6372: 6362:) = ( 6354: 6347: 6340: 6329: 6323: 6312: 6302: 6287: 6284:group structure 6273: 6267: 6261:)) =  6229: 6215: 6202: 6196: 6166: 6160: 6148: 6142: 6136: 6130: 6129:for all points 6087: 6065: 6048: 6042: 6039: 6033: 5991: 5988: 5987: 5949: 5945: 5943: 5940: 5939: 5932: 5926: 5901: 5895: 5894: 5893: 5882: 5879: 5878: 5842: 5836: 5835: 5834: 5832: 5829: 5828: 5791: 5770: 5764: 5763: 5762: 5760: 5757: 5756: 5734: 5728: 5727: 5726: 5725: 5721: 5706: 5702: 5672: 5662: 5646: 5640: 5639: 5638: 5636: 5633: 5632: 5607: 5604: 5603: 5577: 5573: 5571: 5568: 5567: 5518: 5495: 5492: 5491: 5445: 5441: 5403: 5400: 5399: 5378:), then, since 5336: 5316: 5313: 5312: 5305: 5273: 5269: 5251: 5245: 5244: 5243: 5220: 5217: 5216: 5213: 5171: 5165: 5164: 5163: 5161: 5158: 5157: 5113:be the ring of 5094: 5088: 5087: 5086: 5056: 5050: 5049: 5048: 5046: 5043: 5042: 5025: 5019: 5018: 5017: 5015: 5012: 5011: 5006:, the sheaf of 4989: 4987:Structure sheaf 4981: 4972: 4965: 4956: 4947: 4940: 4933: 4924: 4914: 4900: 4894: 4874: 4870: 4855: 4851: 4842: 4838: 4836: 4833: 4832: 4829: 4821: 4807: 4798: 4795: 4787: 4765: 4761: 4759: 4757: 4754: 4753: 4728: 4724: 4722: 4720: 4717: 4716: 4713: 4705: 4691: 4684: 4678: 4674: 4665: 4655: 4652: 4644: 4630: 4626: 4617: 4611: 4593: 4586: 4564: 4550: 4536: 4522: 4512: 4502: 4487: 4473: 4464: 4458: 4451: 4441: 4435: 4429: 4422: 4400: 4393: 4385: 4381: 4372: 4365: 4356: 4347: 4340: 4333: 4324: 4314: 4300: 4294: 4288: 4274: 4264: 4261: 4255: 4239: 4233: 4227: 4221: 4205: 4197: 4181: 4173: 4158: 4149: 4143: 4136: 4132: 4123: 4116: 4107: 4089: 4083: 4077: 4067: 4064: 4056: 4050: 4047: 4039: 4032: 4028: 4019: 4005: 3998: 3994: 3985: 3971: 3965: 3959: 3953: 3947: 3941: 3935: 3920: 3917: 3841: 3837: 3828: 3824: 3822: 3819: 3818: 3791: 3787: 3778: 3774: 3773: 3771: 3769: 3766: 3765: 3736: 3732: 3723: 3719: 3718: 3716: 3695: 3691: 3682: 3678: 3677: 3675: 3660: 3656: 3641: 3637: 3632: 3629: 3628: 3605: 3601: 3586: 3582: 3574: 3565: 3561: 3546: 3542: 3528: 3525: 3524: 3491: 3488: 3487: 3486:if and only if 3447: 3444: 3443: 3364: 3361: 3360: 3359:(in which case 3304:if and only if 3258: 3255: 3254: 3253:if and only if 3232: 3229: 3228: 3189: 3163: 3160: 3159: 3132: 3128: 3113: 3109: 3101: 3098: 3097: 3092:: for an ideal 3051: 3049: 3046: 3045: 3040:that vanish on 3018: 3014: 2999: 2995: 2987: 2984: 2983: 2960: 2868: 2864: 2846: 2842: 2825: 2822: 2821: 2794: 2790: 2775: 2771: 2757: 2754: 2753: 2712: 2708: 2690: 2686: 2684: 2681: 2680: 2677:basic open sets 2612: 2609: 2608: 2547: 2544: 2543: 2510: 2507: 2506: 2487: 2483: 2466: 2463: 2462: 2447: 2441: 2374: 2370: 2361: 2357: 2345: 2341: 2326: 2322: 2309: 2305: 2304: 2300: 2293: 2289: 2285: 2283: 2277: 2266: 2260: 2257: 2256: 2249:defined by the 2233: 2229: 2227: 2224: 2223: 2220:affine subspace 2215: 2211: 2203: 2192: 2180: 2172: 2171:if the rank of 2164: 2138: 2134: 2119: 2115: 2102: 2098: 2097: 2093: 2086: 2082: 2078: 2076: 2074: 2071: 2070: 2063: 2059: 2051: 2043: 2041:Jacobian matrix 2033: 2013: 2009: 1994: 1990: 1979: 1976: 1975: 1952: 1948: 1933: 1929: 1914: 1910: 1895: 1891: 1889: 1886: 1885: 1881: 1878: 1854: 1849: 1848: 1827: 1823: 1814: 1810: 1801: 1797: 1789: 1786: 1785: 1779: 1773: 1767: 1761: 1755: 1749: 1740: 1723: 1718: 1717: 1699: 1695: 1686: 1682: 1674: 1671: 1670: 1661: 1655: 1648: 1644: 1635: 1632:algebraic curve 1614: 1609: 1608: 1590: 1586: 1577: 1573: 1565: 1562: 1561: 1554: 1526: 1522: 1515: 1507: 1505: 1493: 1489: 1482: 1475: 1471: 1464: 1462: 1461: 1457: 1455: 1452: 1451: 1442: 1432: 1422: 1416: 1395: 1384: 1381: 1380: 1374: 1370: 1363: 1361: 1356: 1354: 1352: 1346: 1326: 1321: 1320: 1302: 1298: 1289: 1285: 1271: 1268: 1267: 1261: 1255: 1251: 1245:rational points 1234: 1228: 1214: 1208: 1202: 1174: 1171: 1170: 1164: 1158: 1152: 1146: 1126: 1122: 1108: 1105: 1104: 1098: 1088: 1082: 1076: 1070: 1053: 1049: 1041: 1038: 1037: 1034: 1021: − 16 1009: 1002: 1000:Rational points 968: 964: 962: 959: 958: 928: 923: 922: 920: 917: 916: 891: 889: 886: 885: 859: 855: 838: 835: 834: 825: 821: 811: 800: 794: 790: 740:integral domain 722:coordinate ring 721: 720: 700: 691: 687: 672: 668: 654: 651: 650: 643: 637: 631: 583: 579: 564: 560: 551: 547: 529: 525: 510: 506: 497: 493: 487: 480: 476: 464: 460: 445: 441: 437: 433: 421: 417: 402: 398: 390: 387: 386: 377: 360: 356: 341: 337: 335: 332: 331: 325: 319: 312: 303: 292: 287:. For example, 276: 268: 260: 256: 247: 240: 236: 227: 223: 219: 215: 158: 154: 139: 135: 127: 124: 123: 121:polynomial ring 112: 62: 58: 49: 45: 43: 40: 39: 28: 23: 22: 15: 12: 11: 5: 6920: 6910: 6909: 6895: 6894: 6888: 6868: 6862: 6854:10.1007/b62130 6838:Mumford, David 6834: 6826: 6815:www.jmilne.org 6800: 6794: 6773: 6760: 6733: 6730: 6729: 6728: 6723: 6718: 6711: 6708: 6705: 6704: 6692: 6679: 6667: 6655: 6643: 6642: 6640: 6637: 6636: 6635: 6552: 6551: 6535: 6534: 6524: 6521: 6513: 6502: 6471: 6408: 6328:; the inverse 6280: 6279: 6245:) =  6208: 6190:) =  6178:) =  6154: 6107:) =  6063:multiplication 6035:Main article: 6032: 6029: 6001: 5998: 5995: 5975: 5972: 5969: 5966: 5963: 5960: 5957: 5952: 5948: 5928:Main article: 5925: 5922: 5909: 5904: 5898: 5892: 5889: 5886: 5845: 5839: 5816: 5813: 5810: 5807: 5804: 5801: 5798: 5794: 5790: 5787: 5784: 5781: 5778: 5773: 5767: 5753: 5752: 5737: 5731: 5724: 5720: 5717: 5712: 5709: 5705: 5701: 5698: 5695: 5690: 5687: 5684: 5681: 5678: 5675: 5669: 5666: 5660: 5655: 5652: 5649: 5643: 5611: 5591: 5588: 5585: 5580: 5576: 5543: 5540: 5537: 5534: 5531: 5528: 5525: 5521: 5517: 5514: 5511: 5508: 5505: 5502: 5499: 5456: 5451: 5448: 5444: 5440: 5437: 5434: 5431: 5428: 5425: 5422: 5419: 5416: 5413: 5410: 5407: 5355: 5352: 5349: 5346: 5343: 5339: 5335: 5332: 5329: 5326: 5323: 5320: 5284: 5279: 5276: 5272: 5268: 5265: 5262: 5259: 5254: 5248: 5242: 5239: 5236: 5233: 5230: 5227: 5224: 5208: 5195:). (See also: 5174: 5168: 5102: 5097: 5091: 5085: 5082: 5079: 5076: 5073: 5070: 5067: 5064: 5059: 5053: 5028: 5022: 4988: 4985: 4977: 4970: 4961: 4952: 4945: 4938: 4929: 4922: 4882: 4877: 4873: 4869: 4866: 4863: 4858: 4854: 4850: 4845: 4841: 4825: 4791: 4773: 4768: 4764: 4741: 4736: 4731: 4727: 4709: 4670: 4663: 4648: 4622: 4615: 4410:These are the 4389: 4377: 4370: 4361: 4352: 4345: 4338: 4329: 4322: 4257:Main article: 4254: 4251: 4201: 4177: 4128: 4121: 4112: 4105: 4060: 4043: 4024: 4017: 3990: 3983: 3916: 3913: 3910: 3909: 3906: 3903: 3899: 3898: 3895: 3892: 3888: 3887: 3884: 3881: 3877: 3876: 3873: 3870: 3849: 3844: 3840: 3836: 3831: 3827: 3800: 3794: 3790: 3786: 3781: 3777: 3753: 3750: 3745: 3739: 3735: 3731: 3726: 3722: 3715: 3712: 3709: 3704: 3698: 3694: 3690: 3685: 3681: 3674: 3671: 3668: 3663: 3659: 3655: 3652: 3649: 3644: 3640: 3636: 3616: 3613: 3608: 3604: 3600: 3597: 3594: 3589: 3585: 3581: 3577: 3573: 3568: 3564: 3560: 3557: 3554: 3549: 3545: 3541: 3538: 3535: 3532: 3504: 3501: 3498: 3495: 3475: 3472: 3469: 3466: 3463: 3460: 3457: 3454: 3451: 3407: 3404: 3401: 3398: 3395: 3392: 3389: 3386: 3383: 3380: 3377: 3374: 3371: 3368: 3312:and returning 3289: 3286: 3283: 3280: 3277: 3274: 3271: 3268: 3265: 3262: 3242: 3239: 3236: 3198: 3193: 3188: 3185: 3182: 3179: 3176: 3173: 3170: 3167: 3143: 3140: 3135: 3131: 3127: 3124: 3121: 3116: 3112: 3108: 3105: 3055: 3029: 3026: 3021: 3017: 3013: 3010: 3007: 3002: 2998: 2994: 2991: 2959: 2956: 2900: 2897: 2894: 2891: 2888: 2885: 2882: 2879: 2876: 2871: 2867: 2863: 2860: 2857: 2854: 2849: 2845: 2841: 2838: 2835: 2832: 2829: 2805: 2802: 2797: 2793: 2789: 2786: 2783: 2778: 2774: 2770: 2767: 2764: 2761: 2741: 2738: 2735: 2732: 2729: 2726: 2723: 2720: 2715: 2711: 2707: 2704: 2701: 2698: 2693: 2689: 2661: 2658: 2655: 2652: 2649: 2646: 2643: 2640: 2637: 2634: 2631: 2628: 2625: 2622: 2619: 2616: 2596: 2593: 2590: 2587: 2584: 2581: 2578: 2575: 2572: 2569: 2566: 2563: 2560: 2557: 2554: 2551: 2532: 2529: 2526: 2523: 2520: 2517: 2514: 2495: 2490: 2486: 2482: 2479: 2476: 2473: 2470: 2443:Main article: 2440: 2437: 2428: 2427: 2416: 2413: 2410: 2407: 2404: 2401: 2398: 2395: 2391: 2388: 2385: 2382: 2377: 2373: 2369: 2364: 2360: 2356: 2353: 2348: 2344: 2340: 2337: 2334: 2329: 2325: 2321: 2312: 2308: 2303: 2296: 2292: 2288: 2280: 2275: 2272: 2269: 2265: 2236: 2232: 2176: 2161: 2160: 2149: 2146: 2141: 2137: 2133: 2130: 2127: 2122: 2118: 2114: 2105: 2101: 2096: 2089: 2085: 2081: 2047: 2032:be a point of 2021: 2016: 2012: 2008: 2005: 2002: 1997: 1993: 1989: 1986: 1983: 1963: 1960: 1955: 1951: 1947: 1944: 1941: 1936: 1932: 1928: 1925: 1922: 1917: 1913: 1909: 1906: 1903: 1898: 1894: 1877: 1874: 1862: 1857: 1852: 1847: 1844: 1841: 1838: 1835: 1830: 1826: 1822: 1817: 1813: 1809: 1804: 1800: 1796: 1793: 1726: 1721: 1716: 1713: 1710: 1707: 1702: 1698: 1694: 1689: 1685: 1681: 1678: 1617: 1612: 1607: 1604: 1601: 1598: 1593: 1589: 1585: 1580: 1576: 1572: 1569: 1551: 1550: 1538: 1529: 1525: 1521: 1518: 1513: 1510: 1504: 1496: 1492: 1488: 1485: 1478: 1474: 1470: 1467: 1460: 1415:is a point of 1404: 1399: 1394: 1391: 1388: 1334: 1329: 1324: 1319: 1316: 1313: 1310: 1305: 1301: 1297: 1292: 1288: 1284: 1281: 1278: 1275: 1250:For instance, 1190: 1187: 1184: 1181: 1178: 1134: 1129: 1125: 1121: 1118: 1115: 1112: 1095:rational point 1056: 1052: 1048: 1045: 1032:rational point 1030:Main article: 1001: 998: 997: 996: 985: 971: 967: 955: 939: 936: 931: 926: 913: 901: 898: 894: 882: 870: 865: 862: 858: 854: 851: 848: 845: 842: 789: 786: 718:is called the 707: 703: 699: 694: 690: 686: 683: 680: 675: 671: 667: 664: 661: 658: 617: 616: 605: 601: 597: 594: 591: 586: 582: 578: 575: 572: 567: 563: 559: 554: 550: 546: 543: 540: 537: 532: 528: 524: 521: 518: 513: 509: 505: 500: 496: 490: 483: 479: 475: 472: 467: 463: 459: 456: 453: 448: 444: 440: 436: 432: 429: 424: 420: 416: 413: 410: 405: 401: 397: 394: 363: 359: 355: 352: 349: 344: 340: 311: 308: 281:rational point 182:affine variety 169: 166: 161: 157: 153: 150: 147: 142: 138: 134: 131: 82: 79: 76: 73: 70: 65: 61: 57: 52: 48: 26: 9: 6: 4: 3: 2: 6919: 6908: 6905: 6904: 6902: 6891: 6889:0-521-35662-8 6885: 6880: 6879: 6873: 6869: 6865: 6859: 6855: 6851: 6847: 6843: 6839: 6835: 6833: 6832: 6827: 6816: 6809: 6805: 6801: 6797: 6791: 6784: 6783: 6778: 6774: 6771: 6767: 6763: 6757: 6753: 6749: 6748: 6743: 6739: 6738: 6737: 6727: 6724: 6722: 6721:Affine scheme 6719: 6717: 6714: 6713: 6701: 6696: 6689: 6683: 6677:, p. 94. 6676: 6671: 6664: 6659: 6653: 6648: 6644: 6632: 6627: 6623: 6619: 6612: 6605: 6598: 6591: 6587: 6583: 6577: 6571: 6566: 6562: 6558: 6557:affine scheme 6554: 6553: 6549: 6545: 6541: 6537: 6536: 6532: 6527: 6526: 6520: 6516: 6512: 6505: 6501: 6496: 6492: 6487: 6485: 6479: 6474: 6465: 6459: 6455: 6448: 6443: 6437: 6433: 6427: 6422: 6416: 6411: 6403: 6400: 6397: =  6396: 6393: 6390: =  6389: 6383: 6380: =  6379: 6376: =  6375: 6369: 6365: 6361: 6357: 6350: 6344: 6336: 6332: 6326: 6319: 6315: 6309: 6306: +  6305: 6298: 6294: 6290: 6285: 6276: 6270: 6264: 6260: 6256: 6252: 6248: 6244: 6240: 6236: 6232: 6226: 6223: →  6222: 6218: 6213: 6209: 6205: 6199: 6193: 6189: 6185: 6181: 6177: 6173: 6169: 6163: 6159: 6155: 6151: 6145: 6139: 6133: 6126: 6122: 6118: 6114: 6110: 6106: 6102: 6098: 6094: 6090: 6085: 6084:associativity 6080: 6077: →  6076: 6073: ×  6072: 6068: 6064: 6060: 6059: 6058: 6056: 6053:is called an 6051: 6045: 6038: 6028: 6026: 6022: 6018: 6015: 5999: 5996: 5993: 5973: 5970: 5964: 5961: 5958: 5950: 5946: 5937: 5931: 5921: 5902: 5890: 5887: 5875: 5873: 5869: 5865: 5861: 5843: 5811: 5808: 5802: 5796: 5788: 5785: 5782: 5776: 5771: 5735: 5722: 5718: 5710: 5707: 5703: 5696: 5693: 5688: 5685: 5679: 5673: 5667: 5664: 5658: 5653: 5650: 5647: 5631: 5630: 5629: 5627: 5622: 5609: 5589: 5586: 5583: 5578: 5574: 5565: 5561: 5557: 5554:and thus the 5538: 5535: 5529: 5523: 5515: 5509: 5503: 5497: 5489: 5485: 5481: 5477: 5473: 5470: 5449: 5446: 5442: 5435: 5432: 5423: 5417: 5411: 5408: 5405: 5397: 5393: 5389: 5385: 5381: 5377: 5373: 5369: 5350: 5347: 5344: 5341: 5333: 5330: 5327: 5321: 5318: 5310: 5304: 5302: 5298: 5277: 5274: 5270: 5263: 5260: 5252: 5240: 5234: 5228: 5207: 5205: 5200: 5198: 5194: 5190: 5172: 5155: 5151: 5147: 5143: 5139: 5135: 5131: 5127: 5122: 5120: 5116: 5095: 5083: 5080: 5071: 5065: 5057: 5026: 5009: 5005: 5001: 4996: 4994: 4984: 4980: 4976: 4969: 4964: 4960: 4955: 4951: 4944: 4937: 4932: 4928: 4921: 4917: 4911: 4907: 4903: 4897: 4875: 4871: 4867: 4864: 4861: 4856: 4852: 4843: 4839: 4828: 4824: 4818: 4814: 4810: 4804: 4801: 4794: 4790: 4766: 4762: 4739: 4729: 4725: 4712: 4708: 4702: 4698: 4694: 4687: 4681: 4673: 4669: 4662: 4658: 4651: 4647: 4641: 4637: 4633: 4625: 4621: 4614: 4608: 4604: 4600: 4596: 4589: 4583: 4579: 4575: 4571: 4567: 4561: 4557: 4553: 4547: 4543: 4539: 4533: 4529: 4525: 4519: 4515: 4509: 4505: 4498: 4494: 4490: 4484: 4480: 4476: 4470: 4467: 4461: 4454: 4449: 4444: 4438: 4432: 4425: 4419: 4417: 4413: 4407: 4403: 4397: 4392: 4388: 4380: 4376: 4369: 4364: 4360: 4355: 4351: 4344: 4337: 4332: 4328: 4321: 4317: 4311: 4307: 4303: 4297: 4291: 4286: 4281: 4277: 4271: 4267: 4260: 4250: 4246: 4243: ×  4242: 4236: 4230: 4224: 4217: 4213: 4210: −  4209: 4206: =  4204: 4200: 4193: 4189: 4186: −  4185: 4182: =  4180: 4176: 4171: 4165: 4162: ×  4161: 4155: 4152: 4146: 4139: 4131: 4127: 4120: 4115: 4111: 4104: 4100: 4097: =  4096: 4093: ×  4092: 4086: 4080: 4075: 4070: 4063: 4059: 4053: 4046: 4042: 4035: 4027: 4023: 4016: 4012: 4009: =  4008: 4001: 3993: 3989: 3982: 3978: 3975: =  3974: 3968: 3962: 3956: 3950: 3944: 3938: 3931: 3928: =  3927: 3924: ×  3923: 3907: 3905:maximal ideal 3904: 3901: 3900: 3896: 3893: 3890: 3889: 3886:reduced ring 3885: 3883:radical ideal 3882: 3879: 3878: 3874: 3872:Type of ideal 3871: 3868: 3867: 3864: 3861: 3847: 3842: 3838: 3834: 3829: 3825: 3816: 3792: 3788: 3784: 3779: 3775: 3751: 3737: 3733: 3729: 3724: 3720: 3713: 3710: 3707: 3696: 3692: 3688: 3683: 3679: 3661: 3657: 3653: 3650: 3647: 3642: 3638: 3614: 3606: 3602: 3598: 3595: 3592: 3587: 3583: 3575: 3566: 3562: 3558: 3555: 3552: 3547: 3543: 3536: 3533: 3530: 3522: 3518: 3502: 3499: 3496: 3493: 3470: 3464: 3461: 3455: 3449: 3441: 3437: 3433: 3429: 3424: 3421: 3402: 3396: 3393: 3387: 3381: 3378: 3372: 3366: 3358: 3355:not equal to 3354: 3350: 3346: 3342: 3337: 3335: 3331: 3327: 3323: 3319: 3315: 3311: 3307: 3303: 3287: 3281: 3275: 3272: 3266: 3260: 3240: 3237: 3234: 3226: 3222: 3218: 3214: 3209: 3196: 3191: 3186: 3177: 3171: 3165: 3157: 3141: 3133: 3129: 3125: 3122: 3119: 3114: 3110: 3103: 3095: 3091: 3087: 3083: 3079: 3075: 3072:of the ideal 3071: 3053: 3043: 3027: 3019: 3015: 3011: 3008: 3005: 3000: 2996: 2989: 2981: 2977: 2973: 2970:be ideals of 2969: 2965: 2955: 2953: 2949: 2945: 2941: 2936: 2934: 2930: 2926: 2922: 2918: 2914: 2898: 2892: 2889: 2883: 2877: 2874: 2869: 2865: 2861: 2858: 2852: 2847: 2843: 2839: 2833: 2827: 2819: 2803: 2795: 2791: 2787: 2784: 2781: 2776: 2772: 2765: 2762: 2759: 2736: 2733: 2727: 2721: 2718: 2713: 2709: 2705: 2702: 2696: 2691: 2687: 2678: 2673: 2656: 2653: 2650: 2644: 2641: 2635: 2629: 2626: 2620: 2614: 2594: 2588: 2585: 2579: 2576: 2570: 2564: 2561: 2555: 2549: 2530: 2524: 2518: 2512: 2493: 2488: 2484: 2480: 2474: 2468: 2460: 2457:, called the 2456: 2452: 2446: 2436: 2434: 2414: 2411: 2408: 2405: 2402: 2399: 2396: 2393: 2389: 2386: 2383: 2375: 2371: 2367: 2362: 2358: 2346: 2342: 2338: 2335: 2332: 2327: 2323: 2310: 2306: 2294: 2290: 2278: 2273: 2270: 2267: 2263: 2255: 2254: 2253: 2252: 2234: 2230: 2221: 2209: 2208:tangent space 2200: 2198: 2190: 2184: 2179: 2175: 2170: 2147: 2139: 2135: 2131: 2128: 2125: 2120: 2116: 2103: 2099: 2087: 2083: 2069: 2068: 2067: 2055: 2050: 2046: 2042: 2037: 2014: 2010: 2006: 2003: 2000: 1995: 1991: 1984: 1981: 1961: 1953: 1949: 1945: 1942: 1939: 1934: 1930: 1923: 1920: 1915: 1911: 1907: 1904: 1901: 1896: 1892: 1873: 1860: 1855: 1845: 1839: 1836: 1833: 1828: 1824: 1820: 1815: 1811: 1807: 1802: 1798: 1791: 1782: 1776: 1770: 1764: 1758: 1752: 1746: 1743: 1724: 1714: 1708: 1705: 1700: 1696: 1692: 1687: 1683: 1676: 1667: 1664: 1658: 1652: 1643: 1638: 1633: 1615: 1605: 1599: 1596: 1591: 1587: 1583: 1578: 1574: 1567: 1558: 1536: 1527: 1523: 1519: 1516: 1511: 1508: 1502: 1494: 1490: 1486: 1483: 1476: 1472: 1468: 1465: 1458: 1450: 1449: 1448: 1445: 1440: 1435: 1430: 1425: 1419: 1397: 1392: 1389: 1377: 1349: 1332: 1327: 1317: 1311: 1308: 1303: 1299: 1295: 1290: 1286: 1279: 1276: 1273: 1264: 1258: 1248: 1246: 1242: 1237: 1231: 1226: 1223:) are called 1222: 1217: 1211: 1205: 1188: 1182: 1176: 1167: 1161: 1155: 1149: 1132: 1127: 1123: 1119: 1116: 1113: 1110: 1101: 1096: 1091: 1085: 1079: 1073: 1054: 1050: 1046: 1043: 1033: 1024: 1020: 1017: −  1016: 1013: =  1012: 1006: 994: 990: 989:normalization 986: 969: 965: 956: 953: 937: 934: 929: 914: 899: 896: 883: 863: 860: 856: 846: 840: 833: 828: 819: 814: 807: 803: 797: 792: 791: 785: 783: 779: 774: 772: 768: 764: 760: 759: 753: 749: 745: 741: 737: 733: 729: 725: 705: 701: 692: 688: 684: 681: 678: 673: 669: 662: 659: 656: 649: 648:quotient ring 640: 634: 628: 626: 622: 603: 599: 595: 592: 584: 580: 576: 573: 570: 565: 561: 552: 548: 544: 541: 538: 530: 526: 522: 519: 516: 511: 507: 498: 494: 481: 477: 473: 465: 461: 457: 454: 451: 446: 442: 434: 430: 422: 418: 414: 411: 408: 403: 399: 392: 385: 384: 383: 380: 361: 357: 353: 350: 347: 342: 338: 328: 322: 317: 307: 299: 296: +  295: 290: 286: 282: 274: 266: 255: 254:rational over 251: 243: 235: 230: 213: 208: 206: 202: 197: 195: 191: 187: 183: 167: 159: 155: 151: 148: 145: 140: 136: 129: 122: 118: 111: 107: 103: 99: 77: 74: 71: 63: 59: 55: 50: 46: 37: 32: 19: 6877: 6841: 6829: 6818:. Retrieved 6814: 6795:0-201-510103 6781: 6745: 6735: 6700:Mumford 1999 6695: 6682: 6670: 6663:Milne (2017) 6658: 6647: 6630: 6610: 6603: 6596: 6589: 6585: 6581: 6575: 6569: 6531:real numbers 6514: 6510: 6503: 6499: 6488: 6483: 6477: 6472: 6463: 6457: 6453: 6446: 6435: 6432:vector space 6425: 6414: 6409: 6404: 6398: 6394: 6391: 6387: 6381: 6377: 6373: 6367: 6363: 6359: 6355: 6348: 6342: 6334: 6330: 6324: 6317: 6313: 6307: 6303: 6296: 6292: 6288: 6281: 6274: 6268: 6262: 6258: 6254: 6250: 6246: 6242: 6238: 6234: 6230: 6224: 6220: 6216: 6211: 6203: 6197: 6191: 6187: 6183: 6179: 6175: 6171: 6167: 6161: 6157: 6149: 6143: 6137: 6131: 6124: 6120: 6116: 6112: 6108: 6104: 6100: 6096: 6092: 6088: 6078: 6074: 6070: 6066: 6062: 6054: 6049: 6043: 6040: 6020: 6016: 5933: 5876: 5871: 5867: 5863: 5859: 5754: 5625: 5623: 5563: 5559: 5487: 5483: 5479: 5475: 5471: 5468: 5395: 5391: 5387: 5383: 5379: 5375: 5371: 5367: 5308: 5306: 5300: 5296: 5209: 5201: 5192: 5188: 5153: 5149: 5145: 5141: 5137: 5133: 5129: 5125: 5123: 5118: 5007: 5003: 4999: 4997: 4990: 4978: 4974: 4967: 4962: 4958: 4953: 4949: 4942: 4935: 4930: 4926: 4919: 4915: 4909: 4905: 4901: 4895: 4826: 4822: 4816: 4812: 4808: 4805: 4799: 4792: 4788: 4710: 4706: 4700: 4696: 4692: 4685: 4679: 4671: 4667: 4660: 4656: 4649: 4645: 4639: 4635: 4631: 4623: 4619: 4612: 4606: 4602: 4598: 4594: 4587: 4581: 4577: 4573: 4569: 4565: 4559: 4555: 4551: 4545: 4541: 4537: 4531: 4527: 4523: 4517: 4513: 4507: 4503: 4496: 4492: 4488: 4482: 4478: 4474: 4471: 4465: 4459: 4452: 4442: 4436: 4430: 4423: 4420: 4405: 4401: 4395: 4390: 4386: 4378: 4374: 4367: 4362: 4358: 4353: 4349: 4342: 4335: 4330: 4326: 4319: 4315: 4313:of the form 4309: 4305: 4301: 4295: 4289: 4284: 4279: 4275: 4269: 4265: 4262: 4244: 4240: 4234: 4228: 4222: 4215: 4211: 4207: 4202: 4198: 4191: 4187: 4183: 4178: 4174: 4163: 4159: 4156: 4150: 4144: 4137: 4129: 4125: 4118: 4113: 4109: 4102: 4098: 4094: 4090: 4084: 4078: 4073: 4068: 4061: 4057: 4051: 4044: 4040: 4033: 4025: 4021: 4014: 4010: 4006: 3999: 3991: 3987: 3980: 3976: 3972: 3966: 3960: 3954: 3948: 3942: 3936: 3929: 3925: 3921: 3918: 3862: 3814: 3520: 3516: 3439: 3435: 3431: 3427: 3425: 3419: 3356: 3352: 3348: 3344: 3340: 3338: 3336:is reduced. 3333: 3329: 3325: 3317: 3313: 3309: 3305: 3301: 3224: 3220: 3216: 3212: 3210: 3155: 3093: 3085: 3081: 3077: 3073: 3041: 2979: 2975: 2971: 2967: 2963: 2961: 2951: 2947: 2943: 2939: 2937: 2932: 2920: 2912: 2817: 2674: 2458: 2454: 2450: 2448: 2429: 2207: 2201: 2196: 2182: 2177: 2173: 2168: 2162: 2053: 2048: 2044: 2038: 1879: 1780: 1774: 1768: 1762: 1756: 1750: 1747: 1741: 1668: 1662: 1656: 1653: 1636: 1559: 1552: 1443: 1433: 1423: 1421:that is not 1417: 1375: 1373:that is not 1347: 1345:as it is in 1262: 1256: 1249: 1244: 1235: 1229: 1224: 1221:real numbers 1215: 1209: 1203: 1165: 1159: 1153: 1147: 1099: 1094: 1089: 1083: 1077: 1071: 1035: 1022: 1018: 1014: 1010: 832:localization 826: 812: 805: 801: 795: 777: 775: 770: 762: 755: 751: 747: 743: 735: 731: 727: 719: 638: 632: 629: 624: 620: 618: 378: 326: 320: 315: 313: 310:Introduction 297: 293: 280: 272: 265:real numbers 253: 246: 241: 234:defined over 233: 228: 222:(containing 209: 204: 200: 198: 185: 181: 101: 95: 6872:Reid, Miles 6675:Reid (1988) 6652:Reid (1988) 6626:finite type 6622:irreducible 6057:if it has: 5467:; that is, 4913:defined by 4704:that sends 4168:is not the 4124:,...,  4108:,...,  4055:, and each 4020:,...,  3986:,...,  3894:prime ideal 3068:denote the 2199:otherwise. 2189:codimension 2187:equals the 1560:The circle 1439:unit circle 1225:real points 1103:is a point 646:, then the 625:irreducible 117:polynomials 6863:354063293X 6732:References 6423:of degree 6266:for every 6228:such that 6195:for every 6165:such that 5482:is not in 5398:such that 5010:-algebras 4404:= 1, ..., 4038:Then each 3328:in a ring 3044:, and let 2917:Noetherian 2163:The point 818:saturating 273:real point 6624:, and of 6493:, as the 5786:∈ 5708:− 5694:⁡ 5686:≠ 5668:→ 5610:◻ 5587:∈ 5510:⊂ 5478:and thus 5447:− 5409:∈ 5348:∈ 5331:∈ 5275:− 5223:Γ 5075:Γ 4865:… 4772:¯ 4735:¯ 4412:morphisms 4399:for each 4299:is a map 3835:− 3799:¯ 3785:− 3749:⟩ 3744:¯ 3730:− 3711:… 3703:¯ 3689:− 3673:⟨ 3670:↦ 3651:… 3612:⟩ 3596:… 3580:⟨ 3556:… 3497:⊆ 3462:⊆ 3394:∪ 3302:V(I)=V(J) 3273:⊆ 3238:⊆ 3123:… 3009:… 2862:∈ 2785:… 2763:∈ 2734:≠ 2706:∈ 2627:∩ 2562:∪ 2528:∅ 2406:… 2368:− 2336:… 2302:∂ 2287:∂ 2264:∑ 2129:… 2095:∂ 2080:∂ 2004:… 1943:… 1921:∈ 1905:… 1846:⊆ 1808:− 1715:⊆ 1606:⊆ 1597:− 1469:− 1318:⊆ 1309:− 1120:∩ 1114:∈ 1047:⊆ 935:− 897:− 861:− 799:(that is 682:… 574:… 542:… 520:… 474:∈ 455:… 412:… 351:… 250:-rational 245:are said 149:… 38:given by 6901:Category 6874:(1988). 6840:(1999). 6806:(2017). 6779:(1969). 6744:(1977), 6710:See also 6561:spectrum 6241:),  6103:),  6012:and any 5986:for any 5566:; i.e., 5558:implies 5295:for any 4957:), ..., 4925:, ... , 4904: : 4811: : 4695: : 4634: : 4597: : 4568: : 4554: : 4491: : 4477: : 4416:category 4357:), ..., 4304: : 4285:morphism 4218: ). 2197:singular 788:Examples 756:ring of 108:over an 6820:16 July 6770:0463157 6665:, Ch. 5 6618:reduced 6316:⋅ 6295:,  6253:,  6219::  6186:,  6174:,  6123:,  6115:,  6099:,  6069::  6023:. (cf. 5877:Hence, 5156:and so 4973:, ..., 4948:, ..., 4666:, ..., 4618:, ..., 4414:in the 4373:, ..., 4348:, ..., 4325:, ..., 4247: , 4214:(  4194: ) 4190:(  4117:,  4101:(  4074:product 4013:(  3979:(  3322:reduced 3070:radical 2218:is the 2169:regular 1739:has no 1362:√ 1355:√ 1219:is the 750:or the 201:variety 119:in the 6886:  6860:  6792:  6768:  6758:  5755:where 5474:is in 5370:is in 5132:) = { 4820:sends 4752:where 4384:where 4166:  4072:. The 4066:is in 3970:. Let 3908:field 3764:where 3300:Hence 3154:where 3084:is in 2978:. Let 2195:, and 1766:, the 1642:modulo 1553:where 1429:circle 1252:(1, 0) 6811:(PDF) 6786:(PDF) 6639:Notes 6602:Spec( 6442:basis 6440:if a 5394:) of 5211:Claim 4934:) = ( 4677:from 4334:) = ( 4287:from 3902:point 3519:. If 3434:. If 2927:or a 2925:field 2923:is a 1254:is a 808:= 0 } 730:. If 194:prime 190:ideal 106:zeros 100:, an 6884:ISBN 6858:ISBN 6822:2021 6790:ISBN 6756:ISBN 6597:V(I) 6570:V(I) 6419:the 6385:and 6141:and 5997:> 5124:Let 4535:and 4511:and 4448:dual 4283:, a 4273:and 4196:and 4082:and 4004:and 3952:and 3940:and 3438:and 3351:and 3345:I=JK 3341:V(I) 3314:I(W) 3223:and 2980:I(V) 2966:and 2752:for 2607:and 2039:The 1974:and 1880:Let 1360:/2, 1239:the 1087:, a 987:The 804:\ { 776:The 267:, a 6850:doi 6600:is 6486:. 6444:of 6346:or 6322:or 6272:in 6210:An 6201:in 6156:An 6147:in 6019:on 5665:lim 5299:in 5199:.) 5148:in 5117:on 4982:)). 4893:in 4797:in 4715:to 4683:to 4659:= ( 4446:is 4382:)), 4293:to 4135:in 4076:of 3334:R/I 3306:I=J 3096:in 2938:If 2915:is 2222:of 2214:at 2210:to 2202:If 2191:of 2167:is 2062:at 2058:of 1748:If 1367:/2) 1097:of 1081:of 820:by 784:). 726:of 630:If 627:. 619:An 314:An 252:or 184:or 180:An 96:In 6903:: 6856:. 6848:. 6813:. 6766:MR 6764:, 6750:, 6620:, 6606:), 6588:/ 6584:= 6470:GL 6417:), 6407:GL 6402:. 6388:gg 6378:eg 6374:ge 6371:, 6364:fg 6360:gh 6325:fg 6311:, 6135:, 6127:)) 6061:A 5934:A 5602:. 5303:. 5136:| 5121:. 4995:. 4908:→ 4815:→ 4699:→ 4638:→ 4605:→ 4601:/ 4580:/ 4576:→ 4572:/ 4558:→ 4544:/ 4540:= 4530:/ 4526:= 4516:⊆ 4506:⊆ 4495:→ 4481:→ 4394:∈ 4308:→ 4278:⊆ 4268:⊆ 4148:, 3227:, 2954:. 2435:. 2036:. 1837:16 1651:. 1247:. 773:. 196:. 34:A 6892:. 6866:. 6852:: 6824:. 6798:. 6690:. 6633:. 6631:k 6613:. 6611:R 6604:R 6592:, 6590:I 6586:k 6582:R 6576:k 6550:. 6533:. 6515:q 6511:F 6504:q 6500:F 6480:) 6478:k 6476:( 6473:n 6466:. 6464:k 6458:n 6456:× 6454:n 6449:, 6447:k 6438:; 6436:k 6428:. 6426:n 6415:k 6413:( 6410:n 6399:e 6395:g 6392:g 6382:g 6368:h 6366:) 6358:( 6356:f 6351:. 6349:g 6343:g 6341:− 6337:) 6335:g 6333:( 6331:ι 6320:, 6318:g 6314:f 6308:g 6304:f 6299:) 6297:g 6293:f 6291:( 6289:μ 6277:. 6275:G 6269:g 6263:e 6259:g 6257:( 6255:ι 6251:g 6249:( 6247:μ 6243:g 6239:g 6237:( 6235:ι 6233:( 6231:μ 6225:G 6221:G 6217:ι 6206:; 6204:G 6198:g 6192:g 6188:e 6184:g 6182:( 6180:μ 6176:g 6172:e 6170:( 6168:μ 6162:e 6152:; 6150:G 6144:h 6138:g 6132:f 6125:h 6121:g 6119:( 6117:μ 6113:f 6111:( 6109:μ 6105:h 6101:g 6097:f 6095:( 6093:μ 6091:( 6089:μ 6079:G 6075:G 6071:G 6067:μ 6050:k 6044:G 6021:X 6017:F 6000:0 5994:i 5974:0 5971:= 5968:) 5965:F 5962:, 5959:X 5956:( 5951:i 5947:H 5908:) 5903:X 5897:O 5891:, 5888:X 5885:( 5872:f 5870:( 5868:D 5864:f 5862:( 5860:D 5844:X 5838:O 5815:} 5812:0 5809:= 5806:) 5803:x 5800:( 5797:f 5793:| 5789:A 5783:f 5780:{ 5777:= 5772:x 5766:m 5736:x 5730:m 5723:A 5719:= 5716:] 5711:1 5704:f 5700:[ 5697:A 5689:0 5683:) 5680:x 5677:( 5674:f 5659:= 5654:x 5651:, 5648:X 5642:O 5626:X 5590:A 5584:g 5579:n 5575:f 5564:J 5560:f 5542:} 5539:0 5536:= 5533:) 5530:x 5527:( 5524:f 5520:| 5516:x 5513:{ 5507:) 5504:J 5501:( 5498:V 5488:J 5486:( 5484:V 5480:x 5476:A 5472:g 5469:h 5455:] 5450:1 5443:h 5439:[ 5436:A 5433:= 5430:] 5427:) 5424:h 5421:( 5418:D 5415:[ 5412:k 5406:g 5396:x 5392:h 5390:( 5388:D 5384:x 5380:g 5376:f 5374:( 5372:D 5368:x 5354:} 5351:A 5345:g 5342:h 5338:| 5334:A 5328:h 5325:{ 5322:= 5319:J 5309:g 5301:A 5297:f 5283:] 5278:1 5271:f 5267:[ 5264:A 5261:= 5258:) 5253:X 5247:O 5241:, 5238:) 5235:f 5232:( 5229:D 5226:( 5193:f 5191:( 5189:D 5173:X 5167:O 5154:X 5150:A 5146:f 5142:x 5140:( 5138:f 5134:x 5130:f 5128:( 5126:D 5119:U 5101:) 5096:X 5090:O 5084:, 5081:U 5078:( 5072:= 5069:) 5066:U 5063:( 5058:X 5052:O 5027:X 5021:O 5008:k 5004:A 5000:X 4979:n 4975:a 4971:1 4968:a 4966:( 4963:m 4959:f 4954:n 4950:a 4946:1 4943:a 4941:( 4939:1 4936:f 4931:n 4927:a 4923:1 4920:a 4918:( 4916:φ 4910:W 4906:V 4902:φ 4896:k 4881:) 4876:n 4872:X 4868:, 4862:, 4857:1 4853:X 4849:( 4844:i 4840:f 4827:i 4823:Y 4817:k 4813:k 4809:φ 4802:. 4800:k 4793:i 4789:f 4767:i 4763:f 4740:, 4730:i 4726:f 4711:i 4707:Y 4701:k 4697:k 4693:φ 4688:, 4686:W 4680:V 4675:) 4672:m 4668:f 4664:1 4661:f 4657:φ 4650:i 4646:Y 4640:k 4636:k 4632:φ 4627:. 4624:m 4620:Y 4616:1 4613:Y 4607:k 4603:J 4599:k 4595:ψ 4590:, 4588:k 4582:I 4578:k 4574:J 4570:k 4566:θ 4560:W 4556:V 4552:φ 4546:J 4542:k 4538:k 4532:I 4528:k 4524:k 4518:k 4514:W 4508:k 4504:V 4497:k 4493:k 4489:φ 4483:W 4479:V 4475:φ 4468:. 4466:k 4460:k 4455:. 4453:k 4443:k 4437:k 4431:k 4426:, 4424:k 4408:. 4406:m 4402:i 4396:k 4391:i 4387:f 4379:n 4375:a 4371:1 4368:a 4366:( 4363:m 4359:f 4354:n 4350:a 4346:1 4343:a 4341:( 4339:1 4336:f 4331:n 4327:a 4323:1 4320:a 4318:( 4316:φ 4310:W 4306:V 4302:φ 4296:W 4290:V 4280:k 4276:W 4270:k 4266:V 4245:A 4241:A 4235:k 4229:k 4223:k 4216:g 4212:V 4208:A 4203:g 4199:T 4192:f 4188:V 4184:A 4179:f 4175:U 4164:A 4160:A 4151:W 4145:V 4140:. 4138:A 4133:) 4130:M 4126:g 4122:1 4119:g 4114:N 4110:f 4106:1 4103:f 4099:V 4095:W 4091:V 4085:W 4079:V 4069:k 4062:j 4058:g 4052:k 4045:i 4041:f 4036:. 4034:A 4029:) 4026:M 4022:g 4018:1 4015:g 4011:V 4007:W 4002:, 4000:A 3995:) 3992:N 3988:f 3984:1 3981:f 3977:V 3973:V 3967:k 3961:A 3955:k 3949:k 3943:A 3937:A 3932:, 3930:A 3926:A 3922:A 3848:. 3843:i 3839:a 3830:i 3826:x 3815:R 3793:i 3789:a 3780:i 3776:x 3752:, 3738:n 3734:a 3725:n 3721:x 3714:, 3708:, 3697:1 3693:a 3684:1 3680:x 3667:) 3662:n 3658:a 3654:, 3648:, 3643:1 3639:a 3635:( 3615:, 3607:m 3603:f 3599:, 3593:, 3588:1 3584:f 3576:/ 3572:] 3567:n 3563:x 3559:, 3553:, 3548:1 3544:x 3540:[ 3537:k 3534:= 3531:R 3521:V 3517:V 3503:. 3500:J 3494:I 3474:) 3471:I 3468:( 3465:V 3459:) 3456:J 3453:( 3450:V 3440:J 3436:I 3432:V 3428:k 3420:I 3406:) 3403:K 3400:( 3397:V 3391:) 3388:J 3385:( 3382:V 3379:= 3376:) 3373:I 3370:( 3367:V 3357:I 3353:K 3349:J 3330:R 3326:I 3318:W 3310:W 3288:. 3285:) 3282:I 3279:( 3276:V 3270:) 3267:J 3264:( 3261:V 3241:J 3235:I 3225:J 3221:I 3217:V 3213:k 3197:. 3192:J 3187:= 3184:) 3181:) 3178:J 3175:( 3172:V 3169:( 3166:I 3156:k 3142:, 3139:] 3134:n 3130:x 3126:, 3120:, 3115:1 3111:x 3107:[ 3104:k 3094:J 3086:I 3082:f 3078:f 3074:I 3054:I 3042:V 3028:, 3025:] 3020:n 3016:x 3012:, 3006:, 3001:1 2997:x 2993:[ 2990:k 2976:V 2972:k 2968:J 2964:I 2952:k 2948:V 2944:k 2940:V 2933:k 2921:k 2913:k 2899:, 2896:} 2893:0 2890:= 2887:) 2884:p 2881:( 2878:f 2875:: 2870:n 2866:k 2859:p 2856:{ 2853:= 2848:f 2844:D 2840:= 2837:) 2834:f 2831:( 2828:V 2818:k 2804:. 2801:] 2796:n 2792:x 2788:, 2782:, 2777:1 2773:x 2769:[ 2766:k 2760:f 2740:} 2737:0 2731:) 2728:p 2725:( 2722:f 2719:: 2714:n 2710:k 2703:p 2700:{ 2697:= 2692:f 2688:U 2660:) 2657:T 2654:, 2651:S 2648:( 2645:V 2642:= 2639:) 2636:T 2633:( 2630:V 2624:) 2621:S 2618:( 2615:V 2595:, 2592:) 2589:T 2586:S 2583:( 2580:V 2577:= 2574:) 2571:T 2568:( 2565:V 2559:) 2556:S 2553:( 2550:V 2531:, 2525:= 2522:) 2519:1 2516:( 2513:V 2494:, 2489:n 2485:k 2481:= 2478:) 2475:0 2472:( 2469:V 2455:k 2451:k 2415:. 2412:r 2409:, 2403:, 2400:1 2397:= 2394:j 2390:, 2387:0 2384:= 2381:) 2376:i 2372:a 2363:i 2359:x 2355:( 2352:) 2347:n 2343:a 2339:, 2333:, 2328:1 2324:a 2320:( 2311:i 2307:x 2295:j 2291:f 2279:n 2274:1 2271:= 2268:i 2235:n 2231:k 2216:a 2212:V 2204:a 2193:V 2185:) 2183:a 2181:( 2178:V 2174:J 2165:a 2148:. 2145:) 2140:n 2136:a 2132:, 2126:, 2121:1 2117:a 2113:( 2104:i 2100:x 2088:j 2084:f 2064:a 2060:V 2056:) 2054:a 2052:( 2049:V 2045:J 2034:V 2020:) 2015:n 2011:a 2007:, 2001:, 1996:1 1992:a 1988:( 1985:= 1982:a 1962:, 1959:] 1954:n 1950:x 1946:, 1940:, 1935:1 1931:x 1927:[ 1924:k 1916:r 1912:f 1908:, 1902:, 1897:1 1893:f 1882:V 1861:. 1856:2 1851:C 1843:) 1840:x 1834:+ 1829:2 1825:x 1821:+ 1816:3 1812:x 1803:2 1799:y 1795:( 1792:V 1781:R 1775:V 1769:R 1763:C 1757:C 1751:V 1742:R 1725:2 1720:C 1712:) 1709:1 1706:+ 1701:2 1697:y 1693:+ 1688:2 1684:x 1680:( 1677:V 1663:Q 1657:Q 1649:3 1645:4 1637:Q 1616:2 1611:C 1603:) 1600:3 1592:2 1588:y 1584:+ 1579:2 1575:x 1571:( 1568:V 1555:t 1537:) 1528:2 1524:t 1520:+ 1517:1 1512:t 1509:2 1503:, 1495:2 1491:t 1487:+ 1484:1 1477:2 1473:t 1466:1 1459:( 1444:Q 1434:R 1424:R 1418:V 1403:) 1398:2 1393:, 1390:i 1387:( 1376:Q 1371:V 1364:2 1357:2 1353:( 1348:V 1333:, 1328:2 1323:C 1315:) 1312:1 1304:2 1300:y 1296:+ 1291:2 1287:x 1283:( 1280:V 1277:= 1274:V 1263:R 1257:Q 1236:Q 1230:Q 1216:R 1210:R 1204:C 1189:. 1186:) 1183:k 1180:( 1177:V 1166:V 1160:k 1154:k 1148:V 1133:. 1128:n 1124:k 1117:V 1111:p 1100:V 1093:- 1090:k 1084:K 1078:k 1072:K 1055:n 1051:K 1044:V 1025:. 1023:x 1019:x 1015:x 1011:y 970:n 966:k 954:. 938:0 930:2 925:C 900:0 893:C 881:. 869:] 864:1 857:f 853:[ 850:] 847:X 844:[ 841:k 827:X 822:f 813:f 806:f 802:X 796:X 771:X 744:R 736:I 732:X 728:X 706:I 702:/ 698:] 693:n 689:x 685:, 679:, 674:1 670:x 666:[ 663:k 660:= 657:R 644:X 639:I 633:X 604:. 600:} 596:0 593:= 590:) 585:n 581:a 577:, 571:, 566:1 562:a 558:( 553:m 549:f 545:= 539:= 536:) 531:n 527:a 523:, 517:, 512:1 508:a 504:( 499:1 495:f 489:| 482:n 478:k 471:) 466:n 462:a 458:, 452:, 447:1 443:a 439:( 435:{ 431:= 428:) 423:m 419:f 415:, 409:, 404:1 400:f 396:( 393:V 379:k 362:m 358:f 354:, 348:, 343:1 339:f 327:k 321:k 304:n 298:y 294:x 277:k 269:k 261:k 257:k 248:k 242:k 237:k 229:K 224:k 220:K 216:k 168:. 165:] 160:n 156:X 152:, 146:, 141:1 137:X 133:[ 130:k 113:k 81:) 78:1 75:+ 72:x 69:( 64:2 60:x 56:= 51:2 47:y 20:)

Index

Affine algebraic set

cubic plane curve
algebraic geometry
zeros
algebraically closed field
polynomials
polynomial ring
ideal
prime
Hilbert's Nullstellensatz
real numbers
rational numbers
Fermat's Last Theorem
quotient ring
integral domain
regular functions
#Structure sheaf
Dimension of an algebraic variety
saturating
localization
Hartogs' extension theorem
normalization
integral closure

rational point
real numbers
rational numbers
circle
unit circle

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