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Kazhdan–Lusztig polynomial

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2754: 1606: 2212: 1953: 1261: 2749:{\displaystyle {\begin{aligned}152q^{22}&+3,472q^{21}+38,791q^{20}+293,021q^{19}+1,370,892q^{18}+4,067,059q^{17}+7,964,012q^{16}\\&+11,159,003q^{15}+11,808,808q^{14}+9,859,915q^{13}+6,778,956q^{12}+3,964,369q^{11}+2,015,441q^{10}\\&+906,567q^{9}+363,611q^{8}+129,820q^{7}+41,239q^{6}+11,426q^{5}+2,677q^{4}+492q^{3}+61q^{2}+3q\end{aligned}}} 616: 155:). The representation had two natural bases, and the transition matrix between these two bases is essentially given by the Kazhdan–Lusztig polynomials. The actual Kazhdan–Lusztig construction of their polynomials is more elementary. Kazhdan and Lusztig used this to construct a canonical basis in the 3527:
was already known from the interpretation of coefficients of the Kazhdan–Lusztig polynomials as the dimensions of intersection cohomology groups, irrespective of the conjectures. Conversely, the relation between Kazhdan–Lusztig polynomials and the Ext groups theoretically can be used to prove the
1601:{\displaystyle R_{x,y}={\begin{cases}0,&{\mbox{if }}x\not \leq y\\1,&{\mbox{if }}x=y\\R_{sx,sy},&{\mbox{if }}sx<x{\mbox{ and }}sy<y\\R_{xs,ys},&{\mbox{if }}xs<x{\mbox{ and }}ys<y\\(q-1)R_{sx,y}+qR_{sx,sy},&{\mbox{if }}sx>x{\mbox{ and }}sy<y\end{cases}}} 4141:
Combinatorial properties of Kazhdan–Lusztig polynomials and their generalizations are a topic of active current research. Given their significance in representation theory and algebraic geometry, attempts have been undertaken to develop the theory of Kazhdan–Lusztig polynomials in purely
1617: 1970:. These formulas are tiresome to use by hand for rank greater than about 3, but are well adapted for computers, and the only limit on computing Kazhdan–Lusztig polynomials with them is that for large rank the number of such polynomials exceeds the storage capacity of computers. 4112:
are all tightly controlled by appropriate analogues of Kazhdan–Lusztig polynomials. They admit an elementary description, but the deeper properties of these polynomials necessary for representation theory follow from sophisticated techniques of modern algebraic geometry and
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are determined in terms of coefficients of Kazhdan–Lusztig polynomials. This result demonstrates that all coefficients of the Kazhdan–Lusztig polynomials of a finite Weyl group are non-negative integers. However, positivity for the case of a finite Weyl group
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The coefficients of the Kazhdan–Lusztig polynomials are conjectured to be the dimensions of some homomorphism spaces in Soergel's bimodule category. This is the only known positive interpretation of these coefficients for arbitrary Coxeter groups.
3170: 3468: 415: 3821: 993: 1948:{\displaystyle q^{{\frac {1}{2}}(\ell (w)-\ell (x))}D(P_{x,w})-q^{{\frac {1}{2}}(\ell (x)-\ell (w))}P_{x,w}=\sum _{x<y\leq w}(-1)^{\ell (x)+\ell (y)}q^{{\frac {1}{2}}(-\ell (x)+2\ell (y)-\ell (w))}D(R_{x,y})P_{y,w}} 4126: 1250: 4092:. Much of the later work of Lusztig explored analogues of Kazhdan–Lusztig polynomials in the context of other natural singular algebraic varieties arising in representation theory, in particular, closures of 3224: 2217: 420: 4430: 2901: 794: 4142:
combinatorial fashion, relying to some extent on geometry, but without reference to intersection cohomology and other advanced techniques. This has led to exciting developments in
210: 3678:, and Kazhdan and Lusztig, following a suggestion of Deligne, showed how to express Kazhdan–Lusztig polynomials in terms of intersection cohomology groups of Schubert varieties. 611:{\displaystyle {\begin{aligned}T_{y}T_{w}&=T_{yw},&&{\mbox{if }}\ell (yw)=\ell (y)+\ell (w)\\(T_{s}+1)(T_{s}-q)&=0,&&{\mbox{if }}s\in S.\end{aligned}}} 4059: 3958: 3050: 2778:
paper also put forth two equivalent conjectures, known now as Kazhdan–Lusztig conjectures, which related the values of their polynomials at 1 with representations of complex
4334: 3321: 1101: 407: 4263: 3613: 2765:
showed that any polynomial with constant term 1 and non-negative integer coefficients is the Kazhdan–Lusztig polynomial for some pair of elements of some symmetric group.
1031: 63: 264: 4289: 337: 4222: 311: 139: 4190: 4354: 3263:. Thus, the Kazhdan–Lusztig conjectures describe the Jordan–Hölder multiplicities of Verma modules in any regular integral block of Bernstein–Gelfand–Gelfand 3704: 4097: 3211:). The methods introduced in the course of the proof have guided development of representation theory throughout the 1980s and 1990s, under the name 892: 2195:
The simple values of Kazhdan–Lusztig polynomials for low rank groups are not typical of higher rank groups. For example, for the split form of E
5055: 2774:
The Kazhdan–Lusztig polynomials arise as transition coefficients between their canonical basis and the natural basis of the Hecke algebra. The
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To establish existence of the Kazhdan–Lusztig polynomials, Kazhdan and Lusztig gave a simple recursive procedure for computing the polynomials
1137: 5050: 3893:. Their definition is more complicated, reflecting relative complexity of representations of real groups compared to complex groups. 4591: 4084:
The second paper of Kazhdan and Lusztig established a geometric setting for definition of Kazhdan–Lusztig polynomials, namely, the
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This gave the first proof that all coefficients of Kazhdan–Lusztig polynomials for finite Weyl groups are non-negative integers.
4575: 2058: 3039:{\displaystyle \operatorname {ch} (L_{w})=\sum _{y\leq w}(-1)^{\ell (w)-\ell (y)}P_{y,w}(1)\operatorname {ch} (M_{y})} 4801: 4545: 183: 5065: 4567: 4359: 279: 156: 121: 162:
In their first paper Kazhdan and Lusztig mentioned that their polynomials were related to the failure of local
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Soergel, Wolfgang (2006), "Kazhdan–Lusztig polynomials and indecomposable bimodules over polynomial rings",
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In March 2007, a collaborative project, the "Atlas of Lie groups and representations", announced that the
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The distinction, in the cases directly connection to representation theory, is explained on the level of
3165:{\displaystyle \operatorname {ch} (M_{w})=\sum _{y\leq w}P_{w_{0}w,w_{0}y}(1)\operatorname {ch} (L_{y})} 3463:{\displaystyle P_{y,w}(q)=\sum _{i}q^{i}\dim(\operatorname {Ext} ^{\ell (w)-\ell (y)-2i}(M_{y},L_{w}))} 5060: 4030: 3929: 4294: 1289: 193:
The two bases for the Springer representation reminded Kazhdan and Lusztig of the two bases for the
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Polo, Patrick (1999), "Construction of arbitrary Kazhdan–Lusztig polynomials in symmetric groups",
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conjectures, although this approach to proving them turned out to be more difficult to carry out.
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These conjectures were proved over characteristic 0 algebraically closed fields independently by
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5. Kashiwara (1990) proved a generalization of the Kazhdan–Lusztig conjectures to symmetrizable
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Kobayashi, Masato (2013), "Inequalities on Bruhat graphs, R- and Kazhdan-Lusztig polynomials",
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where each term on the right means: take the complex IC of sheaves whose hyperhomology is the
240: 3827: 3619: 17: 4992: 4268: 3885:. They are analogous to Kazhdan–Lusztig polynomials, but are tailored to representations of 3863:. The odd-dimensional cohomology groups do not appear in the sum because they are all zero. 1006: 316: 5045: 4898: 4833: 4705: 4675: 4627: 4478: 4195: 4109: 3965: 3631: 2779: 289: 206: 124: 3531:
4. Some special cases of the Kazhdan–Lusztig conjectures are easy to verify. For example,
8: 4586: 4512: 4495: 4169: 4114: 4105: 3572: 3556:= 1, since the sum reduces to a single term. On the other hand, the first conjecture for 3297: 3188: 2880: 4837: 4709: 4631: 163: 4974: 4954: 4933: 4915: 4857: 4729: 4651: 4605: 4339: 4085: 3675: 3293: 3200: 194: 4978: 4937: 4886: 4861: 4849: 4797: 4764: 4733: 4721: 4643: 4571: 4541: 3292:
in certain subquotient of the Verma module determined by a canonical filtration, the
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of certain infinite dimensional representations of semisimple Lie algebras, given by
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The Kazhdan–Lusztig polynomials can then be computed recursively using the relation
186:, and gave another definition of such a basis in terms of the dimensions of certain 4964: 4925: 4878: 4841: 4789: 4759: 4713: 4663: 4635: 4609: 4516: 4499: 4122: 4011: 4001: 3889:
semisimple Lie groups, and play major role in the conjectural description of their
3831: 3301: 3204: 3192: 167: 151:. They found a new construction of these representations over the complex numbers ( 4882: 3852:, and then take the dimension of the stalk of this sheaf at any point of the cell 3816:{\displaystyle P_{y,w}(q)=\sum _{i}q^{i}\dim IH_{X_{y}}^{2i}({\overline {X_{w}}})} 4894: 4829: 4793: 4701: 4671: 4623: 4474: 4093: 3296:. The Jantzen conjecture in regular integral case was proved in a later paper of 214: 144: 117: 5007: 4969: 4811: 4777: 4745: 4687: 4670:, Progress in Mathematics, vol. 87, Boston: Birkhauser, pp. 407–433, 4101: 3920: 3538:
is the antidominant Verma module, which is known to be simple. This means that
700: 70: 4929: 4666:(1990), "The Kazhdan–Lusztig conjecture for symmetrizable KacMoody algebras", 4587:"Kazhdan–Lusztig Polynomials: History, Problems, and Combinatorial Invariance" 5039: 4890: 4853: 4773: 4741: 4725: 4683: 4647: 4533: 3969: 3901: 1967: 202: 86: 66: 3625: 988:{\displaystyle C'_{w}=q^{-{\frac {\ell (w)}{2}}}\sum _{y\leq w}P_{y,w}T_{y}} 221:
to representations of Weyl groups, led to the Kazhdan–Lusztig conjectures.
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for crystallographic Coxeter groups satisfy certain strict inequality: Let
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are locally-finite weight modules over the complex semisimple Lie algebra
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software for computing Kazhdan–Lusztig polynomials for any Coxeter group
5015: 4996: 4845: 4717: 4639: 3515: 3264: 2794: 113: 93: 5029: 4506:, Sér. I Math., vol. 292, Paris: C. R. Acad. Sci., pp. 15–18 4166:
Kobayashi (2013) proved that values of Kazhdan–Lusztig polynomials at
1245:{\displaystyle T_{y^{-1}}^{-1}=\sum _{x}D(R_{x,y})q^{-\ell (x)}T_{x}.} 4920: 4690:(June 1979), "Representations of Coxeter groups and Hecke algebras", 3977: 2200: 148: 97: 4818:(1983), "Singularities of closures of K-orbits on flag manifolds.", 4612:(October 1981), "Kazhdan–Lusztig conjecture and holonomic systems", 3923:. The original (K-L) case is then about the details of decomposing 4959: 4540:, Progress in Mathematics, vol. 182, Boston, MA: Birkhäuser, 703:. From this it follows that the Hecke algebra has an automorphism 4748:(1980a), "A topological approach to Springer's representations", 1958:
using the fact that the two terms on the left are polynomials in
4784:, Proceedings of Symposia in Pure Mathematics, vol. XXXVI, 2786:, addressing a long-standing problem in representation theory. 3575:, together with the fact that all Kazhdan–Lusztig polynomials 2099:(or more generally any Coxeter group of rank at most 2) then 65:
is a member of a family of integral polynomials introduced by
4523:, Advances in Soviet Mathematics, vol. 16, pp. 1–50 3274:
coefficients of Kazhdan–Lusztig polynomials follows from the
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1. The two conjectures are known to be equivalent. Moreover,
1594: 2203:(a variation of Kazhdan–Lusztig polynomials: see below) is 621:
The quadratic second relation implies that each generator
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Relation to intersection cohomology of Schubert varieties
4558:; Brenti, Francesco (2005), "Ch. 5: Kazhdan–Lusztig and 4080:
Generalization to other objects in representation theory
828:, and uniquely determined by the following properties. 108:
In the spring of 1978 Kazhdan and Lusztig were studying
4451:"Computing Kazhdan-Lusztig-Vogan polynomials for split 3900:; or in other terms of actions on analogues of complex 4037: 3936: 1573: 1554: 1464: 1445: 1395: 1376: 1329: 1301: 586: 470: 4995:
from Spring 2005 course on Kazhdan–Lusztig Theory at
4362: 4342: 4297: 4271: 4230: 4198: 4172: 4033: 3932: 3707: 3581: 3324: 3278:, which roughly says that individual coefficients of 3053: 2904: 2215: 1620: 1264: 1140: 1039: 1009: 895: 735: 418: 345: 319: 292: 243: 127: 29: 4599:, Ellwangen: Haus Schönenberg: Research article B49b 3184:
is the element of maximal length of the Weyl group.
682:(obtained by multiplying the quadratic relation for 1255:They can be computed using the recursion relations 4908:Journal of the Institute of Mathematics of Jussieu 4604: 4511: 4494: 4424: 4348: 4328: 4283: 4257: 4216: 4184: 4100:. It turned out that the representation theory of 4053: 3952: 3815: 3607: 3462: 3305: 3208: 3196: 3164: 3038: 2748: 1947: 1600: 1244: 1118:) in terms of more elementary polynomials denoted 1095: 1025: 987: 788: 610: 401: 331: 305: 258: 133: 57: 628:is invertible in the Hecke algebra, with inverse 5037: 5032:for computing Kazhdan–Lusztig-Vogan polynomials. 4566:, Graduate Texts in Mathematics, vol. 231, 4528: 4155: 3869: 3315:showed as a consequence of the conjectures that 4772: 4740: 4150:. Some references are given in the textbook of 3681:More precisely, the Kazhdan–Lusztig polynomial 171: 152: 4682: 4088:of singularities of Schubert varieties in the 2827:where ρ is the half-sum of positive roots (or 2769: 2192:, giving examples of non-constant polynomials. 74: 4554: 4425:{\displaystyle P_{uw}(1)>P_{tu,w}(1)>0} 4151: 4810: 3882: 3877:(also called Kazhdan–Lusztig polynomials or 4448: 5018:for computing Kazhdan–Lusztig polynomials. 4224:be a crystallographic Coxeter system and 1103:-module, called the Kazhdan–Lusztig basis. 270:(the smallest length of an expression for 4968: 4958: 4947:Journal of Combinatorial Theory, Series A 4944: 4919: 4763: 4662: 4154:. A research monograph on the subject is 4127:Beilinson–Bernstein–Deligne decomposition 3859:whose closure is the Schubert variety of 3552:, establishing the second conjecture for 2895:. The Kazhdan–Lusztig conjectures state: 2201:most complicated Lusztig–Vogan polynomial 2059:longest element of a finite Coxeter group 1041: 347: 103: 77:). They are indexed by pairs of elements 789:{\displaystyle D(T_{w})=T_{w^{-1}}^{-1}} 174:they reinterpreted this in terms of the 5008:"Tables of Kazhdan–Lusztig polynomials" 4905: 4782:Schubert varieties and Poincaré duality 4136: 4024:. Then the relevant object of study is 1033:form a basis of the Hecke algebra as a 5038: 4592:Séminaire Lotharingien de Combinatoire 4584: 3514:is odd, so the dimensions of all such 656:. These inverses satisfy the relation 5056:Representation theory of Lie algebras 3650:is a disjoint union of affine spaces 3225:Borho–Jantzen's translation principle 4868: 4265:its Kazhdan–Lusztig polynomials. If 2762: 816:) are indexed by a pair of elements 5051:Representation theory of Lie groups 5002: 4538:Singular loci of Schubert varieties 4067:L–V polynomials had been calculated 1003:of the Hecke algebra. The elements 999:are invariant under the involution 13: 4521:A proof of the Jantzen conjectures 157:Hecke algebra of the Coxeter group 14: 5077: 4986: 4336:, then there exists a reflection 3879:Kazhdan–Lusztig–Vogan polynomials 3845:), take its cohomology of degree 3259:for any dominant integral weight 2838:be its irreducible quotient, the 800:can be seen to be an involution. 409:, with multiplication defined by 92:, which can in particular be the 4668:The Grothendieck Festschrift, II 803:The Kazhdan–Lusztig polynomials 205:. This analogy, and the work of 4564:Combinatorics of Coxeter Groups 4054:{\displaystyle K\backslash G/B} 3953:{\displaystyle B\backslash G/B} 3667:. The closures of these spaces 3270:2. A similar interpretation of 3213:geometric representation theory 4442: 4413: 4407: 4382: 4376: 4329:{\displaystyle P_{uw}(1)>1} 4317: 4311: 4251: 4245: 4211: 4199: 4156:Billey & Lakshmibai (2000) 3810: 3790: 3730: 3724: 3457: 3454: 3428: 3411: 3405: 3396: 3390: 3379: 3347: 3341: 3159: 3146: 3137: 3131: 3073: 3060: 3033: 3020: 3011: 3005: 2984: 2978: 2969: 2963: 2956: 2946: 2924: 2911: 1926: 1907: 1899: 1896: 1890: 1881: 1875: 1863: 1857: 1848: 1828: 1822: 1813: 1807: 1800: 1790: 1744: 1741: 1735: 1726: 1720: 1714: 1693: 1674: 1666: 1663: 1657: 1648: 1642: 1636: 1498: 1486: 1224: 1218: 1204: 1185: 1090: 1045: 932: 926: 752: 739: 566: 547: 544: 525: 518: 512: 503: 497: 488: 479: 396: 351: 253: 247: 52: 46: 1: 4883:10.1090/S1088-4165-99-00074-6 4786:American Mathematical Society 4488: 4161: 3870:Generalization to real groups 266:for the length of an element 224: 172:Kazhdan & Lusztig (1980b) 16:In the mathematical field of 4765:10.1016/0001-8708(80)90005-5 4148:pattern-avoidance phenomenon 3805: 2840:simple highest weight module 1096:{\displaystyle \mathbb {Z} } 402:{\displaystyle \mathbb {Z} } 274:as a product of elements of 7: 4467:Nieuw Archief voor Wiskunde 4258:{\displaystyle {P_{uw}(q)}} 4152:Björner & Brenti (2005) 3915:is a complex Lie group and 3608:{\displaystyle P_{y,w_{0}}} 3573:character of a Verma module 2770:Kazhdan–Lusztig conjectures 1973: 153:Kazhdan & Lusztig 1980a 10: 5082: 4970:10.1016/j.jcta.2012.10.001 4585:Brenti, Francesco (2003), 4449:van Leeuwen, Marc (2008), 3883:Lusztig & Vogan (1983) 3659:parameterized by elements 3218: 58:{\displaystyle P_{y,w}(q)} 22:Kazhdan–Lusztig polynomial 4930:10.1017/S1474748007000023 4504:Localisation de g-modules 3964:a classical theme of the 3875:Lusztig–Vogan polynomials 3838:(the closure of the cell 2887:) for the character of a 2879:, and therefore admit an 864:their degree is at most ( 729:. More generally one has 159:and its representations. 4821:Inventiones Mathematicae 4794:10.1090/pspum/036/573434 4693:Inventiones Mathematicae 4615:Inventiones Mathematicae 4435: 3992:maximal compact subgroup 3571:and the formula for the 286:has a basis of elements 259:{\displaystyle \ell (w)} 110:Springer representations 5066:Algebraic combinatorics 4751:Advances in Mathematics 4144:algebraic combinatorics 4119:intersection cohomology 3976:. The L-V case takes a 3642:of the algebraic group 3189:Alexander Beilinson 188:intersection cohomology 176:intersection cohomology 141:-adic cohomology groups 4426: 4350: 4330: 4285: 4284:{\displaystyle u<w} 4259: 4218: 4186: 4069:for the split form of 4055: 3954: 3817: 3609: 3569:Weyl character formula 3464: 3285:are multiplicities of 3201:Jean-Luc Brylinski 3166: 3040: 2750: 1949: 1602: 1246: 1097: 1027: 1026:{\displaystyle C'_{w}} 989: 790: 612: 403: 333: 332:{\displaystyle w\in W} 307: 260: 135: 104:Motivation and history 59: 4871:Representation Theory 4427: 4351: 4331: 4286: 4260: 4219: 4217:{\displaystyle (W,S)} 4187: 4117:, such as the use of 4110:affine Hecke algebras 4056: 3968:, and before that of 3955: 3881:) were introduced in 3828:intersection homology 3818: 3610: 3465: 3167: 3041: 2780:semisimple Lie groups 2751: 2127:is the Coxeter group 2085:is the Coxeter group 1950: 1603: 1247: 1098: 1028: 990: 791: 613: 404: 334: 308: 306:{\displaystyle T_{w}} 261: 136: 134:{\displaystyle \ell } 60: 18:representation theory 4788:, pp. 185–203, 4513:Beilinson, Alexandre 4496:Beilinson, Alexandre 4360: 4340: 4295: 4269: 4228: 4196: 4170: 4137:Combinatorial theory 4106:modular Lie algebras 4031: 3966:Bruhat decomposition 3930: 3705: 3632:Bruhat decomposition 3579: 3322: 3051: 2902: 2875:with the Weyl group 2213: 2134:with generating set 2000:has constant term 1. 1618: 1262: 1138: 1037: 1007: 893: 733: 416: 343: 317: 290: 241: 233:with generating set 229:Fix a Coxeter group 207:Jens Carsten Jantzen 125: 27: 4838:1983InMat..71..365L 4710:1979InMat..53..165K 4632:1981InMat..64..387B 4606:Brylinski, Jean-Luc 4185:{\displaystyle q=1} 4115:homological algebra 3789: 3241:can be replaced by 2883:. Let us write ch( 2881:algebraic character 1168: 1022: 908: 785: 219:enveloping algebras 4999:by Monica Vazirani 4846:10.1007/BF01389103 4718:10.1007/BF01390031 4640:10.1007/BF01389272 4422: 4346: 4326: 4281: 4255: 4214: 4182: 4051: 3950: 3813: 3765: 3745: 3676:Schubert varieties 3620:Kac–Moody algebras 3605: 3460: 3362: 3294:Jantzen filtration 3276:Jantzen conjecture 3162: 3094: 3036: 2945: 2842:of highest weight 2812:of highest weight 2746: 2744: 1945: 1789: 1598: 1593: 1577: 1558: 1468: 1449: 1399: 1380: 1333: 1305: 1242: 1181: 1141: 1093: 1023: 1010: 985: 958: 896: 832:They are 0 unless 786: 758: 608: 606: 590: 474: 399: 329: 303: 256: 195:Grothendieck group 168:Schubert varieties 131: 55: 5021:Fokko du Cloux's 4664:Kashiwara, Masaki 4610:Kashiwara, Masaki 4577:978-3-540-44238-7 4517:Bernstein, Joseph 4500:Bernstein, Joseph 4349:{\displaystyle t} 3808: 3736: 3567:follows from the 3353: 3079: 2930: 1846: 1768: 1712: 1634: 1576: 1557: 1467: 1448: 1398: 1379: 1332: 1304: 1172: 943: 939: 589: 473: 184:Robert MacPherson 145:conjugacy classes 67:David Kazhdan 5073: 5061:Algebraic groups 5011: 4981: 4972: 4962: 4940: 4923: 4901: 4864: 4806: 4768: 4767: 4736: 4678: 4658: 4600: 4580: 4550: 4524: 4507: 4482: 4481: 4464: 4459: 4446: 4431: 4429: 4428: 4423: 4406: 4405: 4375: 4374: 4355: 4353: 4352: 4347: 4335: 4333: 4332: 4327: 4310: 4309: 4290: 4288: 4287: 4282: 4264: 4262: 4261: 4256: 4254: 4244: 4243: 4223: 4221: 4220: 4215: 4191: 4189: 4188: 4183: 4123:perverse sheaves 4098:quiver varieties 4094:nilpotent orbits 4060: 4058: 4057: 4052: 4047: 4023: 4012:complexification 4010:, and makes the 4009: 4002:semisimple group 3999: 3985: 3959: 3957: 3956: 3951: 3946: 3858: 3851: 3844: 3832:Schubert variety 3822: 3820: 3819: 3814: 3809: 3804: 3803: 3794: 3788: 3780: 3779: 3778: 3755: 3754: 3744: 3723: 3722: 3673: 3646:with Weyl group 3615:are equal to 1. 3614: 3612: 3611: 3606: 3604: 3603: 3602: 3601: 3513: 3490: 3469: 3467: 3466: 3461: 3453: 3452: 3440: 3439: 3424: 3423: 3372: 3371: 3361: 3340: 3339: 3291: 3284: 3262: 3258: 3240: 3205:Masaki Kashiwara 3193:Joseph Bernstein 3183: 3171: 3169: 3168: 3163: 3158: 3157: 3130: 3129: 3125: 3124: 3109: 3108: 3093: 3072: 3071: 3045: 3043: 3042: 3037: 3032: 3031: 3004: 3003: 2988: 2987: 2944: 2923: 2922: 2870: 2863: 2856: 2837: 2826: 2807: 2755: 2753: 2752: 2747: 2745: 2732: 2731: 2716: 2715: 2700: 2699: 2678: 2677: 2656: 2655: 2634: 2633: 2612: 2611: 2590: 2589: 2565: 2561: 2560: 2533: 2532: 2505: 2504: 2477: 2476: 2449: 2448: 2421: 2420: 2390: 2386: 2385: 2358: 2357: 2330: 2329: 2302: 2301: 2280: 2279: 2258: 2257: 2232: 2231: 2120:and 0 otherwise. 2029: 1954: 1952: 1951: 1946: 1944: 1943: 1925: 1924: 1903: 1902: 1847: 1839: 1832: 1831: 1788: 1764: 1763: 1748: 1747: 1713: 1705: 1692: 1691: 1670: 1669: 1635: 1627: 1607: 1605: 1604: 1599: 1597: 1596: 1578: 1574: 1559: 1555: 1547: 1546: 1519: 1518: 1469: 1465: 1450: 1446: 1438: 1437: 1400: 1396: 1381: 1377: 1369: 1368: 1334: 1330: 1306: 1302: 1280: 1279: 1251: 1249: 1248: 1243: 1238: 1237: 1228: 1227: 1203: 1202: 1180: 1167: 1159: 1158: 1157: 1102: 1100: 1099: 1094: 1089: 1088: 1084: 1065: 1064: 1060: 1044: 1032: 1030: 1029: 1024: 1018: 994: 992: 991: 986: 984: 983: 974: 973: 957: 942: 941: 940: 935: 921: 904: 795: 793: 792: 787: 784: 776: 775: 774: 751: 750: 728: 721: 699:), and also the 695: 688: 681: 655: 627: 617: 615: 614: 609: 607: 591: 587: 583: 559: 558: 537: 536: 475: 471: 467: 462: 461: 442: 441: 432: 431: 408: 406: 405: 400: 395: 394: 390: 371: 370: 366: 350: 338: 336: 335: 330: 312: 310: 309: 304: 302: 301: 265: 263: 262: 257: 215:primitive ideals 164:Poincaré duality 140: 138: 137: 132: 64: 62: 61: 56: 45: 44: 5081: 5080: 5076: 5075: 5074: 5072: 5071: 5070: 5036: 5035: 4989: 4830:Springer-Verlag 4812:Lusztig, George 4804: 4778:Lusztig, George 4746:Lusztig, George 4702:Springer-Verlag 4688:Lusztig, George 4624:Springer-Verlag 4578: 4556:Björner, Anders 4548: 4491: 4486: 4485: 4462: 4458: 4452: 4447: 4443: 4438: 4392: 4388: 4367: 4363: 4361: 4358: 4357: 4341: 4338: 4337: 4302: 4298: 4296: 4293: 4292: 4270: 4267: 4266: 4236: 4232: 4231: 4229: 4226: 4225: 4197: 4194: 4193: 4171: 4168: 4167: 4164: 4139: 4082: 4075: 4043: 4032: 4029: 4028: 4022: 4018: 4008: 4004: 3998: 3994: 3984: 3980: 3942: 3931: 3928: 3927: 3872: 3857: 3853: 3846: 3843: 3839: 3799: 3795: 3793: 3781: 3774: 3770: 3769: 3750: 3746: 3740: 3712: 3708: 3706: 3703: 3702: 3698:) is equal to 3693: 3672: 3668: 3658: 3628: 3597: 3593: 3586: 3582: 3580: 3577: 3576: 3566: 3551: 3544: 3537: 3492: 3487: 3480: 3474: 3448: 3444: 3435: 3431: 3386: 3382: 3367: 3363: 3357: 3329: 3325: 3323: 3320: 3319: 3290: 3286: 3283: 3279: 3260: 3242: 3228: 3221: 3182: 3176: 3153: 3149: 3120: 3116: 3104: 3100: 3099: 3095: 3083: 3067: 3063: 3052: 3049: 3048: 3027: 3023: 2993: 2989: 2959: 2955: 2934: 2918: 2914: 2903: 2900: 2899: 2869: 2865: 2862: 2858: 2843: 2836: 2832: 2813: 2806: 2802: 2797:. For each w ∈ 2772: 2743: 2742: 2727: 2723: 2711: 2707: 2695: 2691: 2673: 2669: 2651: 2647: 2629: 2625: 2607: 2603: 2585: 2581: 2563: 2562: 2556: 2552: 2528: 2524: 2500: 2496: 2472: 2468: 2444: 2440: 2416: 2412: 2388: 2387: 2381: 2377: 2353: 2349: 2325: 2321: 2297: 2293: 2275: 2271: 2253: 2249: 2233: 2227: 2223: 2216: 2214: 2211: 2210: 2198: 2187: 2170: 2158:commuting then 2133: 2111: 2098: 2091: 2073: 2056: 2042: 2012: 1999: 1976: 1933: 1929: 1914: 1910: 1838: 1837: 1833: 1803: 1799: 1772: 1753: 1749: 1704: 1703: 1699: 1681: 1677: 1626: 1625: 1621: 1619: 1616: 1615: 1592: 1591: 1575: and  1572: 1553: 1551: 1530: 1526: 1505: 1501: 1483: 1482: 1466: and  1463: 1444: 1442: 1421: 1417: 1414: 1413: 1397: and  1394: 1375: 1373: 1352: 1348: 1345: 1344: 1328: 1326: 1317: 1316: 1300: 1298: 1285: 1284: 1269: 1265: 1263: 1260: 1259: 1233: 1229: 1211: 1207: 1192: 1188: 1176: 1160: 1150: 1146: 1145: 1139: 1136: 1135: 1126: 1112: 1080: 1073: 1069: 1056: 1052: 1048: 1040: 1038: 1035: 1034: 1014: 1008: 1005: 1004: 979: 975: 963: 959: 947: 922: 920: 916: 912: 900: 894: 891: 890: 811: 777: 767: 763: 762: 746: 742: 734: 731: 730: 727: 723: 720: 716: 701:braid relations 694: 690: 687: 683: 675: 666: 657: 649: 637: 629: 626: 622: 605: 604: 585: 582: 569: 554: 550: 532: 528: 522: 521: 469: 466: 454: 450: 443: 437: 433: 427: 423: 419: 417: 414: 413: 386: 379: 375: 362: 358: 354: 346: 344: 341: 340: 318: 315: 314: 297: 293: 291: 288: 287: 242: 239: 238: 227: 126: 123: 122: 118:algebraic group 106: 34: 30: 28: 25: 24: 12: 11: 5: 5079: 5069: 5068: 5063: 5058: 5053: 5048: 5034: 5033: 5026: 5019: 5012: 5000: 4988: 4987:External links 4985: 4984: 4983: 4953:(2): 470–482, 4942: 4914:(3): 501–525, 4903: 4866: 4808: 4802: 4774:Kazhdan, David 4770: 4758:(2): 222–228, 4742:Kazhdan, David 4738: 4684:Kazhdan, David 4680: 4660: 4602: 4582: 4576: 4562:polynomials", 4552: 4546: 4534:Lakshmibai, V. 4526: 4509: 4490: 4487: 4484: 4483: 4473:(2): 113–116, 4456: 4440: 4439: 4437: 4434: 4421: 4418: 4415: 4412: 4409: 4404: 4401: 4398: 4395: 4391: 4387: 4384: 4381: 4378: 4373: 4370: 4366: 4345: 4325: 4322: 4319: 4316: 4313: 4308: 4305: 4301: 4280: 4277: 4274: 4253: 4250: 4247: 4242: 4239: 4235: 4213: 4210: 4207: 4204: 4201: 4181: 4178: 4175: 4163: 4160: 4138: 4135: 4102:quantum groups 4081: 4078: 4073: 4063: 4062: 4050: 4046: 4042: 4039: 4036: 4020: 4006: 3996: 3982: 3970:Schubert cells 3962: 3961: 3949: 3945: 3941: 3938: 3935: 3921:Borel subgroup 3902:flag manifolds 3871: 3868: 3855: 3841: 3824: 3823: 3812: 3807: 3802: 3798: 3792: 3787: 3784: 3777: 3773: 3768: 3764: 3761: 3758: 3753: 3749: 3743: 3739: 3735: 3732: 3729: 3726: 3721: 3718: 3715: 3711: 3685: 3670: 3654: 3627: 3624: 3600: 3596: 3592: 3589: 3585: 3564: 3549: 3542: 3535: 3485: 3478: 3471: 3470: 3459: 3456: 3451: 3447: 3443: 3438: 3434: 3430: 3427: 3422: 3419: 3416: 3413: 3410: 3407: 3404: 3401: 3398: 3395: 3392: 3389: 3385: 3381: 3378: 3375: 3370: 3366: 3360: 3356: 3352: 3349: 3346: 3343: 3338: 3335: 3332: 3328: 3288: 3281: 3220: 3217: 3180: 3173: 3172: 3161: 3156: 3152: 3148: 3145: 3142: 3139: 3136: 3133: 3128: 3123: 3119: 3115: 3112: 3107: 3103: 3098: 3092: 3089: 3086: 3082: 3078: 3075: 3070: 3066: 3062: 3059: 3056: 3046: 3035: 3030: 3026: 3022: 3019: 3016: 3013: 3010: 3007: 3002: 2999: 2996: 2992: 2986: 2983: 2980: 2977: 2974: 2971: 2968: 2965: 2962: 2958: 2954: 2951: 2948: 2943: 2940: 2937: 2933: 2929: 2926: 2921: 2917: 2913: 2910: 2907: 2867: 2860: 2834: 2804: 2771: 2768: 2767: 2766: 2759: 2758: 2757: 2756: 2741: 2738: 2735: 2730: 2726: 2722: 2719: 2714: 2710: 2706: 2703: 2698: 2694: 2690: 2687: 2684: 2681: 2676: 2672: 2668: 2665: 2662: 2659: 2654: 2650: 2646: 2643: 2640: 2637: 2632: 2628: 2624: 2621: 2618: 2615: 2610: 2606: 2602: 2599: 2596: 2593: 2588: 2584: 2580: 2577: 2574: 2571: 2568: 2566: 2564: 2559: 2555: 2551: 2548: 2545: 2542: 2539: 2536: 2531: 2527: 2523: 2520: 2517: 2514: 2511: 2508: 2503: 2499: 2495: 2492: 2489: 2486: 2483: 2480: 2475: 2471: 2467: 2464: 2461: 2458: 2455: 2452: 2447: 2443: 2439: 2436: 2433: 2430: 2427: 2424: 2419: 2415: 2411: 2408: 2405: 2402: 2399: 2396: 2393: 2391: 2389: 2384: 2380: 2376: 2373: 2370: 2367: 2364: 2361: 2356: 2352: 2348: 2345: 2342: 2339: 2336: 2333: 2328: 2324: 2320: 2317: 2314: 2311: 2308: 2305: 2300: 2296: 2292: 2289: 2286: 2283: 2278: 2274: 2270: 2267: 2264: 2261: 2256: 2252: 2248: 2245: 2242: 2239: 2236: 2234: 2230: 2226: 2222: 2219: 2218: 2205: 2204: 2196: 2193: 2179: 2162: 2131: 2121: 2103: 2096: 2089: 2079: 2065: 2054: 2044: 2034: 2028:) ∈ {0, 1, 2} 2001: 1991: 1975: 1972: 1968:constant terms 1956: 1955: 1942: 1939: 1936: 1932: 1928: 1923: 1920: 1917: 1913: 1909: 1906: 1901: 1898: 1895: 1892: 1889: 1886: 1883: 1880: 1877: 1874: 1871: 1868: 1865: 1862: 1859: 1856: 1853: 1850: 1845: 1842: 1836: 1830: 1827: 1824: 1821: 1818: 1815: 1812: 1809: 1806: 1802: 1798: 1795: 1792: 1787: 1784: 1781: 1778: 1775: 1771: 1767: 1762: 1759: 1756: 1752: 1746: 1743: 1740: 1737: 1734: 1731: 1728: 1725: 1722: 1719: 1716: 1711: 1708: 1702: 1698: 1695: 1690: 1687: 1684: 1680: 1676: 1673: 1668: 1665: 1662: 1659: 1656: 1653: 1650: 1647: 1644: 1641: 1638: 1633: 1630: 1624: 1609: 1608: 1595: 1590: 1587: 1584: 1581: 1571: 1568: 1565: 1562: 1552: 1550: 1545: 1542: 1539: 1536: 1533: 1529: 1525: 1522: 1517: 1514: 1511: 1508: 1504: 1500: 1497: 1494: 1491: 1488: 1485: 1484: 1481: 1478: 1475: 1472: 1462: 1459: 1456: 1453: 1443: 1441: 1436: 1433: 1430: 1427: 1424: 1420: 1416: 1415: 1412: 1409: 1406: 1403: 1393: 1390: 1387: 1384: 1374: 1372: 1367: 1364: 1361: 1358: 1355: 1351: 1347: 1346: 1343: 1340: 1337: 1327: 1325: 1322: 1319: 1318: 1315: 1312: 1309: 1299: 1297: 1294: 1291: 1290: 1288: 1283: 1278: 1275: 1272: 1268: 1253: 1252: 1241: 1236: 1232: 1226: 1223: 1220: 1217: 1214: 1210: 1206: 1201: 1198: 1195: 1191: 1187: 1184: 1179: 1175: 1171: 1166: 1163: 1156: 1153: 1149: 1144: 1131:). defined by 1122: 1110: 1105: 1104: 1092: 1087: 1083: 1079: 1076: 1072: 1068: 1063: 1059: 1055: 1051: 1047: 1043: 1021: 1017: 1013: 997: 996: 995: 982: 978: 972: 969: 966: 962: 956: 953: 950: 946: 938: 934: 931: 928: 925: 919: 915: 911: 907: 903: 899: 885: 884: 881: 807: 783: 780: 773: 770: 766: 761: 757: 754: 749: 745: 741: 738: 725: 718: 692: 685: 671: 662: 645: 633: 624: 619: 618: 603: 600: 597: 594: 584: 581: 578: 575: 572: 570: 568: 565: 562: 557: 553: 549: 546: 543: 540: 535: 531: 527: 524: 523: 520: 517: 514: 511: 508: 505: 502: 499: 496: 493: 490: 487: 484: 481: 478: 468: 465: 460: 457: 453: 449: 446: 444: 440: 436: 430: 426: 422: 421: 398: 393: 389: 385: 382: 378: 374: 369: 365: 361: 357: 353: 349: 339:over the ring 328: 325: 322: 300: 296: 255: 252: 249: 246: 226: 223: 211:Anthony Joseph 203:simple modules 130: 105: 102: 71:George Lusztig 54: 51: 48: 43: 40: 37: 33: 9: 6: 4: 3: 2: 5078: 5067: 5064: 5062: 5059: 5057: 5054: 5052: 5049: 5047: 5044: 5043: 5041: 5031: 5027: 5024: 5020: 5017: 5013: 5009: 5005: 5004:Goresky, Mark 5001: 4998: 4994: 4991: 4990: 4980: 4976: 4971: 4966: 4961: 4956: 4952: 4948: 4943: 4939: 4935: 4931: 4927: 4922: 4917: 4913: 4909: 4904: 4900: 4896: 4892: 4888: 4884: 4880: 4877:(4): 90–104, 4876: 4872: 4867: 4863: 4859: 4855: 4851: 4847: 4843: 4839: 4835: 4831: 4827: 4823: 4822: 4817: 4813: 4809: 4805: 4803:9780821814390 4799: 4795: 4791: 4787: 4783: 4779: 4775: 4771: 4766: 4761: 4757: 4753: 4752: 4747: 4743: 4739: 4735: 4731: 4727: 4723: 4719: 4715: 4711: 4707: 4703: 4699: 4695: 4694: 4689: 4685: 4681: 4677: 4673: 4669: 4665: 4661: 4657: 4653: 4649: 4645: 4641: 4637: 4633: 4629: 4625: 4621: 4617: 4616: 4611: 4607: 4603: 4598: 4594: 4593: 4588: 4583: 4579: 4573: 4569: 4565: 4561: 4557: 4553: 4549: 4547:0-8176-4092-4 4543: 4539: 4535: 4531: 4527: 4522: 4518: 4514: 4510: 4505: 4501: 4497: 4493: 4492: 4480: 4476: 4472: 4468: 4461: 4455: 4445: 4441: 4433: 4419: 4416: 4410: 4402: 4399: 4396: 4393: 4389: 4385: 4379: 4371: 4368: 4364: 4343: 4323: 4320: 4314: 4306: 4303: 4299: 4278: 4275: 4272: 4248: 4240: 4237: 4233: 4208: 4205: 4202: 4179: 4176: 4173: 4159: 4157: 4153: 4149: 4145: 4134: 4130: 4128: 4124: 4120: 4116: 4111: 4107: 4103: 4099: 4095: 4091: 4087: 4077: 4072: 4068: 4048: 4044: 4040: 4034: 4027: 4026: 4025: 4016: 4013: 4003: 3993: 3989: 3979: 3975: 3971: 3967: 3947: 3943: 3939: 3933: 3926: 3925: 3924: 3922: 3918: 3914: 3910: 3906: 3903: 3899: 3898:double cosets 3894: 3892: 3891:unitary duals 3888: 3884: 3880: 3876: 3867: 3864: 3862: 3850: 3837: 3833: 3829: 3800: 3796: 3785: 3782: 3775: 3771: 3766: 3762: 3759: 3756: 3751: 3747: 3741: 3737: 3733: 3727: 3719: 3716: 3713: 3709: 3701: 3700: 3699: 3697: 3692: 3688: 3684: 3679: 3677: 3666: 3662: 3657: 3653: 3649: 3645: 3641: 3637: 3633: 3623: 3621: 3616: 3598: 3594: 3590: 3587: 3583: 3574: 3570: 3563: 3559: 3555: 3548: 3541: 3534: 3529: 3526: 3521: 3517: 3511: 3507: 3503: 3499: 3495: 3488: 3481: 3449: 3445: 3441: 3436: 3432: 3425: 3420: 3417: 3414: 3408: 3402: 3399: 3393: 3387: 3383: 3376: 3373: 3368: 3364: 3358: 3354: 3350: 3344: 3336: 3333: 3330: 3326: 3318: 3317: 3316: 3314: 3309: 3307: 3303: 3300: and 3299: 3295: 3277: 3273: 3268: 3266: 3257: 3253: 3249: 3245: 3239: 3235: 3231: 3227:implies that 3226: 3216: 3214: 3210: 3206: 3203: and 3202: 3198: 3194: 3191: and 3190: 3185: 3179: 3154: 3150: 3143: 3140: 3134: 3126: 3121: 3117: 3113: 3110: 3105: 3101: 3096: 3090: 3087: 3084: 3080: 3076: 3068: 3064: 3057: 3054: 3047: 3028: 3024: 3017: 3014: 3008: 3000: 2997: 2994: 2990: 2981: 2975: 2972: 2966: 2960: 2952: 2949: 2941: 2938: 2935: 2931: 2927: 2919: 2915: 2908: 2905: 2898: 2897: 2896: 2894: 2890: 2886: 2882: 2878: 2874: 2855: 2851: 2847: 2841: 2830: 2825: 2821: 2817: 2811: 2800: 2796: 2792: 2787: 2785: 2781: 2777: 2764: 2761: 2760: 2739: 2736: 2733: 2728: 2724: 2720: 2717: 2712: 2708: 2704: 2701: 2696: 2692: 2688: 2685: 2682: 2679: 2674: 2670: 2666: 2663: 2660: 2657: 2652: 2648: 2644: 2641: 2638: 2635: 2630: 2626: 2622: 2619: 2616: 2613: 2608: 2604: 2600: 2597: 2594: 2591: 2586: 2582: 2578: 2575: 2572: 2569: 2567: 2557: 2553: 2549: 2546: 2543: 2540: 2537: 2534: 2529: 2525: 2521: 2518: 2515: 2512: 2509: 2506: 2501: 2497: 2493: 2490: 2487: 2484: 2481: 2478: 2473: 2469: 2465: 2462: 2459: 2456: 2453: 2450: 2445: 2441: 2437: 2434: 2431: 2428: 2425: 2422: 2417: 2413: 2409: 2406: 2403: 2400: 2397: 2394: 2392: 2382: 2378: 2374: 2371: 2368: 2365: 2362: 2359: 2354: 2350: 2346: 2343: 2340: 2337: 2334: 2331: 2326: 2322: 2318: 2315: 2312: 2309: 2306: 2303: 2298: 2294: 2290: 2287: 2284: 2281: 2276: 2272: 2268: 2265: 2262: 2259: 2254: 2250: 2246: 2243: 2240: 2237: 2235: 2228: 2224: 2220: 2209: 2208: 2207: 2206: 2202: 2194: 2191: 2186: 2182: 2178: 2174: 2169: 2165: 2161: 2157: 2153: 2149: 2145: 2141: 2137: 2130: 2126: 2122: 2119: 2115: 2110: 2106: 2102: 2095: 2088: 2084: 2080: 2077: 2072: 2068: 2064: 2060: 2053: 2049: 2045: 2041: 2037: 2033: 2027: 2023: 2019: 2015: 2010: 2006: 2002: 1998: 1994: 1990: 1986: 1982: 1978: 1977: 1971: 1969: 1965: 1961: 1940: 1937: 1934: 1930: 1921: 1918: 1915: 1911: 1904: 1893: 1887: 1884: 1878: 1872: 1869: 1866: 1860: 1854: 1851: 1843: 1840: 1834: 1825: 1819: 1816: 1810: 1804: 1796: 1793: 1785: 1782: 1779: 1776: 1773: 1769: 1765: 1760: 1757: 1754: 1750: 1738: 1732: 1729: 1723: 1717: 1709: 1706: 1700: 1696: 1688: 1685: 1682: 1678: 1671: 1660: 1654: 1651: 1645: 1639: 1631: 1628: 1622: 1614: 1613: 1612: 1588: 1585: 1582: 1579: 1569: 1566: 1563: 1560: 1548: 1543: 1540: 1537: 1534: 1531: 1527: 1523: 1520: 1515: 1512: 1509: 1506: 1502: 1495: 1492: 1489: 1479: 1476: 1473: 1470: 1460: 1457: 1454: 1451: 1439: 1434: 1431: 1428: 1425: 1422: 1418: 1410: 1407: 1404: 1401: 1391: 1388: 1385: 1382: 1370: 1365: 1362: 1359: 1356: 1353: 1349: 1341: 1338: 1335: 1323: 1320: 1313: 1310: 1307: 1295: 1292: 1286: 1281: 1276: 1273: 1270: 1266: 1258: 1257: 1256: 1239: 1234: 1230: 1221: 1215: 1212: 1208: 1199: 1196: 1193: 1189: 1182: 1177: 1173: 1169: 1164: 1161: 1154: 1151: 1147: 1142: 1134: 1133: 1132: 1130: 1125: 1121: 1117: 1113: 1085: 1081: 1077: 1074: 1070: 1066: 1061: 1057: 1053: 1049: 1019: 1015: 1011: 1002: 998: 980: 976: 970: 967: 964: 960: 954: 951: 948: 944: 936: 929: 923: 917: 913: 909: 905: 901: 897: 889: 888: 887: 886: 882: 879: 875: 871: 867: 863: 859: 855: 851: 847: 843: 839: 835: 831: 830: 829: 827: 823: 819: 815: 810: 806: 801: 799: 781: 778: 771: 768: 764: 759: 755: 747: 743: 736: 714: 710: 706: 702: 698: 679: 674: 670: 665: 661: 653: 648: 644: 641: 636: 632: 601: 598: 595: 592: 579: 576: 573: 571: 563: 560: 555: 551: 541: 538: 533: 529: 515: 509: 506: 500: 494: 491: 485: 482: 476: 463: 458: 455: 451: 447: 445: 438: 434: 428: 424: 412: 411: 410: 391: 387: 383: 380: 376: 372: 367: 363: 359: 355: 326: 323: 320: 298: 294: 285: 281: 280:Hecke algebra 277: 273: 269: 250: 244: 236: 232: 222: 220: 216: 212: 208: 204: 200: 199:Verma modules 196: 191: 189: 185: 181: 177: 173: 169: 165: 160: 158: 154: 150: 146: 142: 128: 119: 115: 111: 101: 99: 95: 91: 88: 87:Coxeter group 84: 80: 76: 72: 69: and 68: 49: 41: 38: 35: 31: 23: 19: 4950: 4946: 4921:math/0403496 4911: 4907: 4874: 4870: 4825: 4819: 4816:Vogan, David 4781: 4755: 4749: 4697: 4691: 4667: 4619: 4613: 4596: 4590: 4563: 4559: 4537: 4530:Billey, Sara 4520: 4503: 4470: 4466: 4453: 4444: 4165: 4147: 4140: 4131: 4090:flag variety 4083: 4070: 4064: 4014: 3987: 3974:Grassmannian 3963: 3916: 3912: 3908: 3904: 3895: 3886: 3878: 3874: 3873: 3865: 3860: 3848: 3835: 3825: 3695: 3690: 3686: 3682: 3680: 3664: 3660: 3655: 3651: 3647: 3643: 3639: 3635: 3629: 3617: 3561: 3557: 3553: 3546: 3539: 3532: 3530: 3524: 3519: 3518:in category 3509: 3505: 3501: 3497: 3493: 3491:vanishes if 3483: 3476: 3472: 3310: 3275: 3271: 3269: 3255: 3251: 3247: 3243: 3237: 3233: 3229: 3222: 3212: 3186: 3177: 3174: 2892: 2888: 2884: 2876: 2872: 2853: 2849: 2845: 2823: 2819: 2815: 2810:Verma module 2798: 2793:be a finite 2790: 2788: 2784:Lie algebras 2775: 2773: 2189: 2184: 2180: 2176: 2172: 2167: 2163: 2159: 2155: 2151: 2147: 2143: 2139: 2135: 2128: 2124: 2117: 2113: 2108: 2104: 2100: 2093: 2086: 2082: 2075: 2074:= 1 for all 2070: 2066: 2062: 2051: 2047: 2039: 2035: 2031: 2025: 2021: 2017: 2013: 2008: 2004: 1996: 1992: 1988: 1984: 1980: 1963: 1959: 1957: 1610: 1254: 1128: 1123: 1119: 1115: 1108: 1106: 1000: 883:The elements 877: 873: 869: 865: 861: 857: 853: 849: 845: 842:Bruhat order 837: 833: 825: 821: 817: 813: 808: 804: 802: 797: 712: 708: 704: 696: 677: 672: 668: 663: 659: 651: 646: 642: 639: 634: 630: 620: 283: 275: 271: 267: 237:, and write 234: 230: 228: 192: 180:Mark Goresky 161: 107: 89: 82: 78: 21: 15: 5046:Polynomials 4832:: 365–379, 4704:: 165–184, 4626:: 387–410, 3674:are called 3313:David Vogan 2831:), and let 2829:Weyl vector 2776:Inventiones 2763:Polo (1999) 707:that sends 143:related to 5040:Categories 4997:U.C. Davis 4489:References 4356:such that 4162:Inequality 4146:, such as 3634:the space 3516:Ext groups 3265:category O 2801:denote by 2795:Weyl group 856:, and for 225:Definition 147:which are 114:Weyl group 94:Weyl group 4979:205929043 4960:1211.4305 4938:120459494 4891:1088-4165 4862:120917588 4854:0020-9910 4780:(1980b), 4734:120098142 4726:0020-9910 4648:0020-9910 4038:∖ 3978:real form 3937:∖ 3806:¯ 3760:⁡ 3738:∑ 3473:and that 3426:⁡ 3415:− 3403:ℓ 3400:− 3388:ℓ 3377:⁡ 3355:∑ 3302:Bernstein 3298:Beilinson 3199:) and by 3144:⁡ 3088:≤ 3081:∑ 3058:⁡ 3018:⁡ 2976:ℓ 2973:− 2961:ℓ 2950:− 2939:≤ 2932:∑ 2909:⁡ 1888:ℓ 1885:− 1873:ℓ 1855:ℓ 1852:− 1820:ℓ 1805:ℓ 1794:− 1783:≤ 1770:∑ 1733:ℓ 1730:− 1718:ℓ 1697:− 1655:ℓ 1652:− 1640:ℓ 1493:− 1216:ℓ 1213:− 1174:∑ 1162:− 1152:− 1075:− 952:≤ 945:∑ 924:ℓ 918:− 880:) − 1)/2. 779:− 769:− 715:and each 596:∈ 561:− 510:ℓ 495:ℓ 477:ℓ 381:− 324:∈ 245:ℓ 213:relating 149:unipotent 129:ℓ 98:Lie group 5030:software 5016:programs 5014:The GAP 4993:Readings 4656:18403883 4568:Springer 4536:(2000), 4519:(1993), 4502:(1981), 4086:geometry 4000:in that 2891:-module 2112:is 1 if 1974:Examples 1966:without 1556:if  1447:if  1378:if  1331:if  1311:≰ 1303:if  1020:′ 906:′ 848:), 1 if 840:(in the 588:if  472:if  278:). The 190:groups. 5023:Coxeter 4899:1698201 4834:Bibcode 4706:Bibcode 4676:1106905 4628:Bibcode 4479:2454587 3830:of the 3630:By the 3304: ( 3219:Remarks 3207: ( 3195: ( 2857:. Both 2808:be the 2150:} with 2057:is the 796:; also 112:of the 73: ( 5028:Atlas 4977:  4936:  4897:  4889:  4860:  4852:  4800:  4732:  4724:  4674:  4654:  4646:  4574:  4544:  4477:  3911:where 3175:where 2188:= 1 + 2171:= 1 + 116:of an 85:of a 4975:S2CID 4955:arXiv 4934:S2CID 4916:arXiv 4858:S2CID 4828:(2), 4730:S2CID 4700:(2), 4652:S2CID 4622:(3), 4463:(PDF) 4436:Notes 3972:in a 2185:acbca 2175:and 2061:then 2030:then 1987:then 860:< 680:) = 0 667:+ 1)( 170:. In 96:of a 4887:ISSN 4850:ISSN 4798:ISBN 4722:ISSN 4644:ISSN 4572:ISBN 4542:ISBN 4417:> 4386:> 4321:> 4291:and 4276:< 4125:and 4108:and 4096:and 3990:, a 3887:real 3504:) + 3475:Ext( 3306:1993 3254:) − 3236:) − 3209:1981 3197:1981 2864:and 2852:) − 2822:) − 2789:Let 2782:and 2199:the 2168:bacb 2154:and 2043:= 1. 2020:) − 2011:and 1962:and 1777:< 1586:< 1567:> 1477:< 1458:< 1408:< 1389:< 872:) − 313:for 209:and 201:and 182:and 166:for 75:1979 20:, a 4965:doi 4951:120 4926:doi 4879:doi 4842:doi 4790:doi 4760:doi 4714:doi 4636:doi 4017:of 3986:of 3834:of 3757:dim 3663:of 3384:Ext 3374:dim 3311:3. 3308:). 3282:y,w 3272:all 2705:492 2689:677 2667:426 2645:239 2623:820 2617:129 2601:611 2595:363 2579:567 2573:906 2550:441 2544:015 2522:369 2516:964 2494:956 2488:778 2466:915 2460:859 2438:808 2432:808 2410:003 2404:159 2375:012 2369:964 2347:059 2341:067 2319:892 2313:370 2291:021 2285:293 2269:791 2247:472 2221:152 2138:= { 2123:If 2092:or 2081:If 2046:If 2003:If 1979:If 844:of 824:of 722:to 711:to 689:by 654:− 1 282:of 217:of 178:of 120:on 5042:: 5006:. 4973:, 4963:, 4949:, 4932:, 4924:, 4910:, 4895:MR 4893:, 4885:, 4873:, 4856:, 4848:, 4840:, 4826:71 4824:, 4814:; 4796:, 4776:; 4756:38 4754:, 4744:; 4728:, 4720:, 4712:, 4698:53 4696:, 4686:; 4672:MR 4650:, 4642:, 4634:, 4620:64 4618:, 4608:; 4597:49 4595:, 4589:, 4570:, 4560:R- 4532:; 4515:; 4498:; 4475:MR 4469:, 4465:, 4432:. 4158:. 4129:. 4121:, 4104:, 4076:. 3919:a 3622:. 3560:= 3545:= 3496:+ 3482:, 3267:. 3250:+ 3215:. 3141:ch 3055:ch 3015:ch 2906:ch 2721:61 2661:11 2639:41 2558:10 2530:11 2502:12 2474:13 2446:14 2426:11 2418:15 2398:11 2383:16 2355:17 2327:18 2299:19 2277:20 2263:38 2255:21 2229:22 2181:ac 2146:, 2142:, 2050:= 2007:≤ 1983:≤ 1124:yw 1111:yw 852:= 836:≤ 820:, 809:yw 691:−T 676:− 650:+ 638:= 100:. 81:, 5010:. 4982:. 4967:: 4957:: 4941:. 4928:: 4918:: 4912:6 4902:. 4881:: 4875:3 4865:. 4844:: 4836:: 4807:. 4792:: 4769:. 4762:: 4737:. 4716:: 4708:: 4679:. 4659:. 4638:: 4630:: 4601:. 4581:. 4551:. 4525:. 4508:. 4471:9 4460:" 4457:8 4454:E 4420:0 4414:) 4411:1 4408:( 4403:w 4400:, 4397:u 4394:t 4390:P 4383:) 4380:1 4377:( 4372:w 4369:u 4365:P 4344:t 4324:1 4318:) 4315:1 4312:( 4307:w 4304:u 4300:P 4279:w 4273:u 4252:) 4249:q 4246:( 4241:w 4238:u 4234:P 4212:) 4209:S 4206:, 4203:W 4200:( 4180:1 4177:= 4174:q 4074:8 4071:E 4061:. 4049:B 4045:/ 4041:G 4035:K 4021:R 4019:K 4015:K 4007:R 4005:G 3997:R 3995:K 3988:G 3983:R 3981:G 3960:, 3948:B 3944:/ 3940:G 3934:B 3917:B 3913:G 3909:B 3907:/ 3905:G 3861:y 3856:y 3854:X 3849:i 3847:2 3842:w 3840:X 3836:w 3811:) 3801:w 3797:X 3791:( 3786:i 3783:2 3776:y 3772:X 3767:H 3763:I 3752:i 3748:q 3742:i 3734:= 3731:) 3728:q 3725:( 3720:w 3717:, 3714:y 3710:P 3696:q 3694:( 3691:w 3689:, 3687:y 3683:P 3671:w 3669:X 3665:W 3661:w 3656:w 3652:X 3648:W 3644:G 3640:B 3638:/ 3636:G 3599:0 3595:w 3591:, 3588:y 3584:P 3565:0 3562:w 3558:w 3554:w 3550:1 3547:L 3543:1 3540:M 3536:1 3533:M 3525:W 3520:O 3512:) 3510:y 3508:( 3506:ℓ 3502:w 3500:( 3498:ℓ 3494:j 3489:) 3486:w 3484:L 3479:y 3477:M 3458:) 3455:) 3450:w 3446:L 3442:, 3437:y 3433:M 3429:( 3421:i 3418:2 3412:) 3409:y 3406:( 3397:) 3394:w 3391:( 3380:( 3369:i 3365:q 3359:i 3351:= 3348:) 3345:q 3342:( 3337:w 3334:, 3331:y 3327:P 3289:y 3287:L 3280:P 3261:λ 3256:ρ 3252:ρ 3248:λ 3246:( 3244:w 3238:ρ 3234:ρ 3232:( 3230:w 3181:0 3178:w 3160:) 3155:y 3151:L 3147:( 3138:) 3135:1 3132:( 3127:y 3122:0 3118:w 3114:, 3111:w 3106:0 3102:w 3097:P 3091:w 3085:y 3077:= 3074:) 3069:w 3065:M 3061:( 3034:) 3029:y 3025:M 3021:( 3012:) 3009:1 3006:( 3001:w 2998:, 2995:y 2991:P 2985:) 2982:y 2979:( 2970:) 2967:w 2964:( 2957:) 2953:1 2947:( 2942:w 2936:y 2928:= 2925:) 2920:w 2916:L 2912:( 2893:X 2889:g 2885:X 2877:W 2873:g 2868:w 2866:L 2861:w 2859:M 2854:ρ 2850:ρ 2848:( 2846:w 2844:− 2835:w 2833:L 2824:ρ 2820:ρ 2818:( 2816:w 2814:− 2805:w 2803:M 2799:W 2791:W 2740:q 2737:3 2734:+ 2729:2 2725:q 2718:+ 2713:3 2709:q 2702:+ 2697:4 2693:q 2686:, 2683:2 2680:+ 2675:5 2671:q 2664:, 2658:+ 2653:6 2649:q 2642:, 2636:+ 2631:7 2627:q 2620:, 2614:+ 2609:8 2605:q 2598:, 2592:+ 2587:9 2583:q 2576:, 2570:+ 2554:q 2547:, 2541:, 2538:2 2535:+ 2526:q 2519:, 2513:, 2510:3 2507:+ 2498:q 2491:, 2485:, 2482:6 2479:+ 2470:q 2463:, 2457:, 2454:9 2451:+ 2442:q 2435:, 2429:, 2423:+ 2414:q 2407:, 2401:, 2395:+ 2379:q 2372:, 2366:, 2363:7 2360:+ 2351:q 2344:, 2338:, 2335:4 2332:+ 2323:q 2316:, 2310:, 2307:1 2304:+ 2295:q 2288:, 2282:+ 2273:q 2266:, 2260:+ 2251:q 2244:, 2241:3 2238:+ 2225:q 2197:8 2190:q 2183:, 2177:P 2173:q 2166:, 2164:b 2160:P 2156:c 2152:a 2148:c 2144:b 2140:a 2136:S 2132:3 2129:A 2125:W 2118:w 2116:≤ 2114:y 2109:w 2107:, 2105:y 2101:P 2097:2 2094:A 2090:1 2087:A 2083:W 2078:. 2076:y 2071:w 2069:, 2067:y 2063:P 2055:0 2052:w 2048:w 2040:w 2038:, 2036:y 2032:P 2026:y 2024:( 2022:ℓ 2018:w 2016:( 2014:ℓ 2009:w 2005:y 1997:w 1995:, 1993:y 1989:P 1985:w 1981:y 1964:q 1960:q 1941:w 1938:, 1935:y 1931:P 1927:) 1922:y 1919:, 1916:x 1912:R 1908:( 1905:D 1900:) 1897:) 1894:w 1891:( 1882:) 1879:y 1876:( 1870:2 1867:+ 1864:) 1861:x 1858:( 1849:( 1844:2 1841:1 1835:q 1829:) 1826:y 1823:( 1817:+ 1814:) 1811:x 1808:( 1801:) 1797:1 1791:( 1786:w 1780:y 1774:x 1766:= 1761:w 1758:, 1755:x 1751:P 1745:) 1742:) 1739:w 1736:( 1727:) 1724:x 1721:( 1715:( 1710:2 1707:1 1701:q 1694:) 1689:w 1686:, 1683:x 1679:P 1675:( 1672:D 1667:) 1664:) 1661:x 1658:( 1649:) 1646:w 1643:( 1637:( 1632:2 1629:1 1623:q 1589:y 1583:y 1580:s 1570:x 1564:x 1561:s 1549:, 1544:y 1541:s 1538:, 1535:x 1532:s 1528:R 1524:q 1521:+ 1516:y 1513:, 1510:x 1507:s 1503:R 1499:) 1496:1 1490:q 1487:( 1480:y 1474:s 1471:y 1461:x 1455:s 1452:x 1440:, 1435:s 1432:y 1429:, 1426:s 1423:x 1419:R 1411:y 1405:y 1402:s 1392:x 1386:x 1383:s 1371:, 1366:y 1363:s 1360:, 1357:x 1354:s 1350:R 1342:y 1339:= 1336:x 1324:, 1321:1 1314:y 1308:x 1296:, 1293:0 1287:{ 1282:= 1277:y 1274:, 1271:x 1267:R 1240:. 1235:x 1231:T 1225:) 1222:x 1219:( 1209:q 1205:) 1200:y 1197:, 1194:x 1190:R 1186:( 1183:D 1178:x 1170:= 1165:1 1155:1 1148:y 1143:T 1129:q 1127:( 1120:R 1116:q 1114:( 1109:P 1091:] 1086:2 1082:/ 1078:1 1071:q 1067:, 1062:2 1058:/ 1054:1 1050:q 1046:[ 1042:Z 1016:w 1012:C 1001:D 981:y 977:T 971:w 968:, 965:y 961:P 955:w 949:y 937:2 933:) 930:w 927:( 914:q 910:= 902:w 898:C 878:y 876:( 874:ℓ 870:w 868:( 866:ℓ 862:w 858:y 854:w 850:y 846:W 838:w 834:y 826:W 822:w 818:y 814:q 812:( 805:P 798:D 782:1 772:1 765:w 760:T 756:= 753:) 748:w 744:T 740:( 737:D 726:s 724:T 719:s 717:T 713:q 709:q 705:D 697:q 693:s 686:s 684:T 678:q 673:s 669:T 664:s 660:T 658:( 652:q 647:s 643:T 640:q 635:s 631:T 625:s 623:T 602:. 599:S 593:s 580:, 577:0 574:= 567:) 564:q 556:s 552:T 548:( 545:) 542:1 539:+ 534:s 530:T 526:( 519:) 516:w 513:( 507:+ 504:) 501:y 498:( 492:= 489:) 486:w 483:y 480:( 464:, 459:w 456:y 452:T 448:= 439:w 435:T 429:y 425:T 397:] 392:2 388:/ 384:1 377:q 373:, 368:2 364:/ 360:1 356:q 352:[ 348:Z 327:W 321:w 299:w 295:T 284:W 276:S 272:w 268:w 254:) 251:w 248:( 235:S 231:W 90:W 83:w 79:y 53:) 50:q 47:( 42:w 39:, 36:y 32:P

Index

representation theory
David Kazhdan
George Lusztig
1979
Coxeter group
Weyl group
Lie group
Springer representations
Weyl group
algebraic group
{\displaystyle \ell } -adic cohomology groups
conjugacy classes
unipotent
Kazhdan & Lusztig 1980a
Hecke algebra of the Coxeter group
Poincaré duality
Schubert varieties
Kazhdan & Lusztig (1980b)
intersection cohomology
Mark Goresky
Robert MacPherson
intersection cohomology
Grothendieck group
Verma modules
simple modules
Jens Carsten Jantzen
Anthony Joseph
primitive ideals
enveloping algebras
Hecke algebra

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