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Compact operator

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2958: 7319: 6835: 2694: 5387: 2953:{\displaystyle \dim \ker \left(T-\lambda \operatorname {Id} _{X}\right)=\dim {\big (}X/\operatorname {Im} \left(T-\lambda \operatorname {Id} _{X}\right){\big )}=\dim \ker \left(T^{*}-\lambda \operatorname {Id} _{X^{*}}\right)=\dim {\big (}X^{*}/\operatorname {Im} \left(T^{*}-\lambda \operatorname {Id} _{X^{*}}\right){\big )}} 3547:
into a Fredholm integral equation. Existence of the solution and spectral properties then follow from the theory of compact operators; in particular, an elliptic boundary value problem on a bounded domain has infinitely many isolated eigenvalues. One consequence is that a solid body can vibrate only
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Somewhat confusingly, compact operators are sometimes referred to as "completely continuous" in older literature, even though they are not necessarily completely continuous by the definition of that phrase in modern terminology.
3801: 4161: 3322: 4815: 2338: 1812: 3661: 4686: 292:, it is true that any compact operator is a limit of finite-rank operators, so that the class of compact operators can be defined alternatively as the closure of the set of finite-rank operators in the 4351: 3704: 4221: 3955: 3393: 2660: 2624: 945: 5991: 2287: 1594: 1494: 872: 2201: 4261: 3909: 3857: 1246: 3357: 3144: 4030: 4002: 3460: 6156: 3080: 821: 3109: 2689: 2588: 2507: 2148: 7208: 6093: 4287: 4068: 786: 1370: 1320: 2992: 4533: 2252: 4462: 3164: 2559: 2533: 2070: 1927: 541: 377: 75: 4422: 1093: 3242: 1697: 1520: 1443: 1408: 1219: 1193: 1154: 1128: 5726: 3213: 2340:
is closed. This is essential in developing the spectral properties of compact operators. One can notice the similarity between this property and the fact that, if
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of all bounded operators on the space. Indeed, the compact operators on an infinite-dimensional separable Hilbert space form a maximal ideal, so the
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a linear operator. Then the following statements are equivalent, and some of them are used as the principal definition by different authors
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of the operator, and the series on the right hand side converges in the operator norm. The singular values can
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at isolated frequencies, given by the eigenvalues, and arbitrarily high vibration frequencies always exist.
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William McLean, Strongly Elliptic Systems and Boundary Integral Equations, Cambridge University Press, 2000
4223:. While all trace-class operators are compact operators, the converse is not necessarily true. For example 7279: 7223: 7187: 6820: 6810: 6794: 6494: 6443: 6343: 6328: 5602: 4477: 4389: 1700: 305: 297: 262:
is a compact operator; indeed, the class of compact operators is a natural generalization of the class of
6789: 6489: 6476: 6458: 6423: 5654: 1022: 6263: 5351: 5185:. Texts in Mathematical Sciences. Vol. 12 (2nd ed.). New York: Springer-Verlag. p. 292. 4007: 3536: 3968: 3421: 7262: 6805: 6749: 6728: 6068: 6047: 5961: 5846: 5809: 5290:. International Series in Pure and Applied Mathematics. Vol. 8 (Second ed.). New York, NY: 4844: 3556: 3413: 3050: 1815: 791: 263: 3088: 2668: 2567: 2480: 2121: 7228: 7166: 6880: 6688: 6683: 6641: 6220: 5871: 5607: 5088: 3552: 1848: 104: 31: 4266: 4035: 1890:
A bounded linear operator between Banach spaces is compact if and only if its adjoint is compact (
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For Hilbert spaces, another equivalent definition of compact operators is given as follows.
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is the unknown function to be solved for) behaves much like as in finite dimensions. The
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on an infinite-dimensional Banach space has spectrum that is either a finite subset of
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Functional analysis, Sobolev spaces and partial differential equations
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The compact operators from a Banach space to itself form a two-sided
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only at zero. If the sequence becomes stationary at zero, that is
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The origin of the theory of compact operators is in the theory of
5119:"A counterexample to the approximation problem in Banach spaces" 4810:{\displaystyle (Tf)(x)=\int _{\Omega }k(x,y)f(y)\,\mathrm {d} y} 2333:{\displaystyle \operatorname {Im} ({\operatorname {Id} _{X}}-T)} 6853: 6138: 5486: 1807:{\displaystyle B(Y,Z)\circ K(X,Y)\circ B(W,X)\subseteq K(W,Z),} 5380: 3957:
is a sequence of positive numbers with limit zero, called the
3656:{\displaystyle ({\mathcal {H}},\langle \cdot ,\cdot \rangle )} 4889: 4887: 4681:{\displaystyle (Tf)(x)=\int _{0}^{x}f(t)g(t)\,\mathrm {d} t.} 233:, but the definition can be extended to more general spaces. 3691: 3681: 3627: 5013: 5011: 5009: 4979: 4977: 4975: 4973: 4971: 4969: 4967: 4965: 4963: 296:. Whether this was true in general for Banach spaces (the 4346:{\textstyle \sum _{n=1}^{\infty }|\lambda _{n}|=\infty } 3699:{\displaystyle T\colon {\mathcal {H}}\to {\mathcal {H}}} 1049:
If a linear operator is compact, then it is continuous.
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is the limit of finite rank operators. Notably, this "
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are orthonormal sets (not necessarily complete), and
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are Hilbert spaces, then every compact operator from
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Topological Vector Spaces, Distributions and Kernels
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Pages displaying wikidata descriptions as a fallback
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Pages displaying wikidata descriptions as a fallback
4074:, a finite-dimensional range, and can be written as 973:
is Banach, these statements are also equivalent to:
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Unsourced material may be challenged and removed. 4999:, (2005) London Mathematical Society Student Texts 4216:{\displaystyle \operatorname {Tr} (|T|)<\infty } 300:) was an unsolved question for many years; in 1973 7209:Spectral theory of ordinary differential equations 6094:Spectral theory of ordinary differential equations 5164:Introductory functional analysis with applications 4809: 4680: 4527: 4456: 4416: 4345: 4281: 4255: 4215: 4167:An important subclass of compact operators is the 4155: 4062: 4024: 3996: 3949: 3903: 3851: 3795: 3698: 3655: 3604: 3454: 3387: 3351: 3316: 3236: 3207: 3179: 3158: 3138: 3103: 3074: 3039: 3007: 2986: 2952: 2683: 2654: 2618: 2582: 2553: 2527: 2501: 2466: 2439: 2418: 2397: 2375: 2353: 2332: 2281: 2246: 2195: 2142: 2110: 2085: 2064: 2028: 2000: 1974: 1945: 1921: 1872: 1839: 1806: 1691: 1665: 1633: 1608: 1588: 1540: 1514: 1488: 1437: 1402: 1364: 1314: 1264: 1240: 1213: 1187: 1148: 1122: 1087: 1037: 1012: 990: 964: 939: 887: 866: 815: 780: 753: 732: 705: 679: 657: 632: 606: 584: 559: 535: 503: 473: 452: 422: 400: 371: 279: 249: 221: 191: 167: 143: 119: 95: 69: 5992:Schröder–Bernstein theorems for operator algebras 5259:An introduction to partial differential equations 4543:converging to zero, the multiplication operator ( 3950:{\displaystyle \lambda _{1},\lambda _{2},\ldots } 3571:. More generally, the compact operators form an 3388:{\displaystyle T-\lambda \operatorname {Id} _{X}} 2655:{\displaystyle T-\lambda \operatorname {Id} _{X}} 2619:{\displaystyle T-\lambda \operatorname {Id} _{X}} 3412:A crucial property of compact operators is the 203:, and so continuous. Some authors require that 5230:Narici, Lawrence; Beckenstein, Edward (2011). 3527:An important example of a compact operator is 1818:of sets is taken element-wise. In particular, 6865: 6150: 5498: 4916: 4369:be Banach spaces. A bounded linear operator 2945: 2874: 2800: 2750: 8: 4480:, then every completely continuous operator 4140: 4121: 3898: 3866: 3846: 3814: 3780: 3761: 3647: 3635: 940:{\displaystyle (Tx_{n})_{n\in \mathbb {N} }} 304:gave a counter-example, building on work by 2282:{\displaystyle {\operatorname {Id} _{X}}-T} 1589:{\displaystyle (T_{n})_{n\in \mathbf {N} }} 1489:{\displaystyle (T_{n})_{n\in \mathbf {N} }} 867:{\displaystyle (x_{n})_{n\in \mathbb {N} }} 6900: 6872: 6858: 6850: 6157: 6143: 6135: 5505: 5491: 5483: 2196:{\displaystyle T^{*}\colon X^{*}\to X^{*}} 5471:Learn how and when to remove this message 5136: 5087:. Vol. 96 (2nd ed.). New York: 4799: 4798: 4762: 4732: 4707: : Î© Ă— Î© â†’  4667: 4666: 4636: 4631: 4601: 4519: 4513: 4445: 4433: 4405: 4396: 4332: 4326: 4317: 4311: 4300: 4294: 4268: 4243: 4234: 4228: 4199: 4191: 4180: 4147: 4128: 4115: 4105: 4094: 4082: 4037: 4018: 4017: 4009: 3976: 3970: 3935: 3922: 3916: 3886: 3873: 3864: 3834: 3821: 3812: 3787: 3768: 3755: 3745: 3734: 3722: 3690: 3689: 3680: 3679: 3671: 3626: 3625: 3620: 3597: 3484:(1918). It shows that a compact operator 3423: 3379: 3364: 3329: 3298: 3290: 3255: 3249: 3223: 3199: 3193: 3172: 3151: 3116: 3090: 3052: 3032: 3000: 2970: 2944: 2943: 2930: 2925: 2909: 2889: 2883: 2873: 2872: 2850: 2845: 2829: 2799: 2798: 2787: 2758: 2749: 2748: 2728: 2696: 2691:then the following are finite and equal: 2670: 2646: 2631: 2610: 2595: 2569: 2540: 2514: 2509:is any bounded linear operator then both 2482: 2453: 2432: 2411: 2390: 2368: 2346: 2314: 2309: 2298: 2266: 2261: 2259: 2224: 2187: 2174: 2161: 2155: 2123: 2103: 2078: 2045: 2021: 1993: 1967: 1938: 1902: 1856: 1823: 1718: 1678: 1652: 1626: 1601: 1579: 1572: 1562: 1553: 1527: 1501: 1479: 1472: 1462: 1453: 1415: 1380: 1327: 1277: 1257: 1232: 1226: 1200: 1165: 1135: 1100: 1062: 1030: 1005: 983: 957: 931: 930: 923: 913: 901: 880: 858: 857: 850: 840: 831: 793: 767: 746: 725: 698: 672: 650: 625: 599: 577: 552: 516: 490: 466: 436: 415: 393: 352: 272: 266:in an infinite-dimensional setting. When 242: 208: 184: 160: 136: 112: 82: 50: 7162:Group algebra of a locally compact group 5038: 4256:{\textstyle \lambda _{n}={\frac {1}{n}}} 3024:, which would necessarily be the origin. 4883: 3904:{\displaystyle \{g_{1},g_{2},\ldots \}} 3852:{\displaystyle \{f_{1},f_{2},\ldots \}} 3492:which includes 0, or the spectrum is a 1448:given a sequence of compact operators 1241:{\displaystyle \operatorname {Id} _{X}} 1195:denotes the space of compact operators 331:; the compactness property is shown by 6296:Uniform boundedness (Banach–Steinhaus) 5017: 4893: 4699:More generally, if Ω is any domain in 4505:Every finite rank operator is compact. 4469: 3352:{\displaystyle \lambda \in \sigma (T)} 3139:{\displaystyle \lambda \in \sigma (T)} 2036:is a Banach space and there exists an 1445:(in the norm topology). Equivalently, 5825:Spectral theory of normal C*-algebras 5623:Spectral theory of normal C*-algebras 5358:. Mineola, N.Y.: Dover Publications. 4997:A Short Course on Banach Space Theory 4983: 4905: 4070:, then the operator has finite rank, 1703:" is false for general Banach spaces 199:). Such an operator is necessarily a 7: 5820:Spectral theory of compact operators 5409:adding citations to reliable sources 5292:McGraw-Hill Science/Engineering/Math 4927: 4925: 4873:Spectral theory of compact operators 3512:with finite multiplicities (so that 3478:spectral theory of compact operators 5257:Renardy, M.; Rogers, R. C. (2004). 5183:Fundamentals of Functional Analysis 4692:is indeed compact follows from the 3408:Origins in integral equation theory 977:the image of any bounded subset of 644:the image of any bounded subset of 5972:Cohen–Hewitt factorization theorem 4938:. H.. BrĂ©zis. New York: Springer. 4800: 4763: 4668: 4340: 4312: 4276: 4210: 3746: 3579:Compact operator on Hilbert spaces 3324:is finite, and for every non-zero 2150:is a compact linear operator, and 2094:is necessarily finite-dimensional. 1130:is the space of bounded operators 947:contains a converging subsequence. 460:is a relatively compact subset of 27:Type of continuous linear operator 25: 5977:Extensions of symmetric operators 4840:Compact operator on Hilbert space 4025:{\displaystyle N\in \mathbb {N} } 3714:if it can be written in the form 3585:Compact operator on Hilbert space 339:is derived from this connection. 323:gives rise to a compact operator 7318: 7317: 7244:Topological quantum field theory 6834: 6833: 5795:Positive operator-valued measure 5385: 5207:. New York: Wiley-Interscience. 5061:. Springer-Verlag. Section 2.4. 3997:{\displaystyle \lambda _{N+k}=0} 3455:{\displaystyle (\lambda K+I)u=f} 1580: 1480: 6821:With the approximation property 6079:Rayleigh–Faber–Krahn inequality 5396:needs additional citations for 5081:A Course in Functional Analysis 5059:A course in functional analysis 4357:Completely continuous operators 3545:elliptic boundary value problem 3480:then follows, and it is due to 3075:{\displaystyle 0\in \sigma (T)} 816:{\displaystyle T(U)\subseteq V} 387:if there exists a neighborhood 6284:Open mapping (Banach–Schauder) 4795: 4789: 4783: 4771: 4752: 4746: 4743: 4734: 4663: 4657: 4651: 4645: 4621: 4615: 4612: 4603: 4576:), define the linear operator 4451: 4435: 4411: 4398: 4333: 4318: 4273: 4204: 4200: 4192: 4188: 3686: 3650: 3622: 3440: 3425: 3346: 3340: 3299: 3291: 3284: 3278: 3133: 3127: 3104:{\displaystyle \lambda \neq 0} 3069: 3063: 2981: 2975: 2684:{\displaystyle \lambda \neq 0} 2583:{\displaystyle \lambda \neq 0} 2502:{\displaystyle S\colon X\to X} 2493: 2327: 2306: 2241: 2235: 2180: 2143:{\displaystyle T\colon X\to X} 2134: 2056: 1929:is bounded and compact, then: 1913: 1867: 1861: 1834: 1828: 1798: 1786: 1777: 1765: 1756: 1744: 1735: 1723: 1683: 1569: 1555: 1506: 1469: 1455: 1432: 1420: 1397: 1385: 1359: 1347: 1338: 1332: 1309: 1297: 1288: 1282: 1205: 1182: 1170: 1140: 1117: 1105: 920: 903: 847: 833: 804: 798: 571:the image of the unit ball of 527: 447: 441: 363: 61: 1: 7040:Uniform boundedness principle 5987:Limiting absorption principle 5085:Graduate Texts in Mathematics 5003:, Cambridge University Press. 3047:is infinite-dimensional then 5613:Singular value decomposition 5320:; Wolff, Manfred P. (1999). 4847: â€“ mathematical theorem 4282:{\displaystyle n\to \infty } 4063:{\displaystyle k=1,2,\dots } 3543:, can be used to convert an 2626:is closed and the kernel of 2448:is finite-dimensional, then 2293:of index 0. In particular, 1932:the closure of the range of 781:{\displaystyle V\subseteq Y} 6505:Radially convex/Star-shaped 6490:Pre-compact/Totally bounded 6044:Hearing the shape of a drum 5727:Decomposition of a spectrum 3612:on an infinite-dimensional 1548:are Banach) and given that 1365:{\displaystyle K(X)=K(X,X)} 1315:{\displaystyle B(X)=B(X,X)} 7370: 7183:Invariant subspace problem 6191:Continuous linear operator 5632:Special Elements/Operators 5181:Kutateladze, S.S. (1996). 4868:Strictly singular operator 4854:Fredholm integral equation 3582: 2987:{\displaystyle \sigma (T)} 321:Fredholm integral equation 7344:Compactness (mathematics) 7313: 6903: 6829: 6536:Algebraic interior (core) 6278:Vector-valued Hahn–Banach 6166:Topological vector spaces 6104:Superstrong approximation 5967:Banach algebra cohomology 5800:Projection-valued measure 5785:Borel functional calculus 5557:Projection-valued measure 5322:Topological Vector Spaces 5232:Topological Vector Spaces 5166:. John Wiley & Sons. 4917:Schaefer & Wolff 1999 4528:{\displaystyle \ell ^{p}} 3520:has a finite-dimensional 3472:is a given function, and 3166:is an eigenvalue of both 2247:{\displaystyle T\in K(X)} 2040:bounded compact operator 826:for any bounded sequence 381:topological vector spaces 107:, with the property that 7152:Spectrum of a C*-algebra 6366:Topological homomorphism 6226:Topological vector space 5696:Spectrum of a C*-algebra 5567:Spectrum of a C*-algebra 5162:Kreyszig, Erwin (1978). 5041:, Theorems 2.5-3, 2.5-5. 4703:and the integral kernel 4457:{\displaystyle (Tx_{n})} 3535:, which, along with the 3524:for all complex λ ≠ 0). 3500:which has 0 as its only 3159:{\displaystyle \lambda } 2554:{\displaystyle T\circ S} 2528:{\displaystyle S\circ T} 2065:{\displaystyle T:X\to X} 1922:{\displaystyle T:X\to Y} 1883:Any compact operator is 1410:is a closed subspace of 536:{\displaystyle T:X\to Y} 372:{\displaystyle T:X\to Y} 70:{\displaystyle T:X\to Y} 7249:Noncommutative geometry 6124:Wiener–Khinchin theorem 6059:Kuznetsov trace formula 6034:Almost Mathieu operator 5852:Banach function algebra 5841:Amenable Banach algebra 5598:Gelfand–Naimark theorem 5552:Noncommutative topology 4417:{\displaystyle (x_{n})} 3468:is a compact operator, 1088:{\displaystyle X,Y,Z,W} 343:Equivalent formulations 7305:Tomita–Takesaki theory 7280:Approximation property 7224:Calculus of variations 6424:Absolutely convex/disk 6099:Sturm–Liouville theory 5997:Sherman–Takeda theorem 5877:Tomita–Takesaki theory 5652:Hermitian/Self-adjoint 5603:Gelfand representation 4817:is a compact operator. 4811: 4713:Hilbert–Schmidt kernel 4682: 4529: 4478:reflexive Banach space 4464:is norm-convergent in 4458: 4418: 4347: 4316: 4283: 4257: 4217: 4157: 4110: 4064: 4026: 3998: 3951: 3905: 3853: 3797: 3750: 3700: 3657: 3606: 3456: 3389: 3353: 3318: 3238: 3237:{\displaystyle r>0} 3209: 3181: 3160: 3140: 3105: 3076: 3041: 3020:, and has at most one 3009: 2988: 2954: 2685: 2662:is finite-dimensional. 2656: 2620: 2584: 2561:are compact operators. 2555: 2529: 2503: 2468: 2441: 2420: 2399: 2377: 2355: 2334: 2283: 2248: 2197: 2144: 2118:is a Banach space and 2112: 2087: 2066: 2030: 2009:is finite-dimensional. 2002: 1976: 1947: 1923: 1874: 1841: 1808: 1701:approximation property 1693: 1692:{\displaystyle X\to Y} 1667: 1635: 1610: 1590: 1542: 1516: 1515:{\displaystyle X\to Y} 1490: 1439: 1438:{\displaystyle B(X,Y)} 1404: 1403:{\displaystyle K(X,Y)} 1366: 1316: 1266: 1242: 1215: 1214:{\displaystyle X\to Y} 1189: 1188:{\displaystyle K(X,Y)} 1150: 1149:{\displaystyle X\to Y} 1124: 1123:{\displaystyle B(X,Y)} 1089: 1039: 1014: 992: 966: 941: 889: 868: 817: 782: 755: 734: 707: 681: 659: 634: 608: 586: 568:is a compact operator; 561: 537: 505: 475: 454: 424: 402: 373: 298:approximation property 281: 251: 223: 193: 175:(subsets with compact 169: 145: 121: 97: 71: 7300:Banach–Mazur distance 7263:Generalized functions 6459:Complemented subspace 6273:hyperplane separation 5593:Gelfand–Mazur theorem 4812: 4683: 4530: 4459: 4419: 4383:completely continuous 4348: 4296: 4284: 4258: 4218: 4158: 4090: 4065: 4027: 3999: 3952: 3906: 3854: 3798: 3730: 3701: 3658: 3607: 3457: 3390: 3354: 3319: 3239: 3210: 3208:{\displaystyle T^{*}} 3182: 3161: 3141: 3106: 3077: 3042: 3010: 2989: 2955: 2686: 2657: 2621: 2585: 2556: 2530: 2504: 2469: 2442: 2421: 2400: 2378: 2356: 2335: 2284: 2249: 2198: 2145: 2113: 2088: 2067: 2031: 2003: 1977: 1948: 1924: 1887:, but not vice versa. 1875: 1842: 1809: 1694: 1668: 1636: 1611: 1591: 1543: 1517: 1491: 1440: 1405: 1367: 1317: 1267: 1243: 1216: 1190: 1151: 1125: 1090: 1040: 1015: 993: 967: 942: 890: 869: 818: 783: 762:and a compact subset 756: 735: 708: 682: 660: 635: 609: 587: 562: 538: 511:be normed spaces and 506: 476: 455: 425: 403: 374: 282: 264:finite-rank operators 252: 236:Any bounded operator 224: 194: 170: 146: 122: 98: 72: 18:Approximation problem 7045:Kakutani fixed-point 7030:Riesz representation 6709:Locally convex space 6259:Closed graph theorem 6211:Locally convex space 6069:Proto-value function 6048:Dirichlet eigenvalue 5962:Abstract index group 5847:Approximate identity 5810:Rigged Hilbert space 5686:Krein–Rutman theorem 5532:Involution/*-algebra 5405:improve this article 4845:Fredholm alternative 4731: 4715:, then the operator 4600: 4512: 4432: 4395: 4293: 4267: 4227: 4179: 4081: 4036: 4008: 3969: 3915: 3863: 3811: 3721: 3670: 3619: 3596: 3422: 3414:Fredholm alternative 3363: 3328: 3248: 3222: 3192: 3171: 3150: 3115: 3089: 3051: 3031: 2999: 2969: 2695: 2669: 2630: 2594: 2568: 2539: 2513: 2481: 2452: 2431: 2410: 2389: 2367: 2345: 2297: 2258: 2223: 2154: 2122: 2102: 2077: 2044: 2020: 1992: 1987:, then the range of 1966: 1937: 1901: 1873:{\displaystyle B(X)} 1855: 1840:{\displaystyle K(X)} 1822: 1717: 1677: 1651: 1625: 1616:with respect to the 1600: 1552: 1526: 1500: 1452: 1414: 1379: 1326: 1276: 1256: 1225: 1199: 1164: 1134: 1099: 1061: 1029: 1004: 982: 956: 900: 879: 830: 792: 766: 745: 724: 697: 671: 649: 624: 598: 576: 551: 515: 489: 465: 453:{\displaystyle T(U)} 435: 414: 392: 351: 271: 241: 207: 183: 159: 135: 111: 105:normed vector spaces 81: 49: 7229:Functional calculus 7188:Mahler's conjecture 7167:Von Neumann algebra 6881:Functional analysis 6689:Interpolation space 6221:Operator topologies 5872:Von Neumann algebra 5608:Polar decomposition 5318:Schaefer, Helmut H. 5287:Functional Analysis 5205:Functional Analysis 5020:, pp. 173–177. 4986:, pp. 103–115. 4932:BrĂ©zis, H. (2011). 4641: 3541:Lax–Milgram theorem 2467:{\displaystyle M+N} 1666:{\displaystyle X,Y} 1541:{\displaystyle X,Y} 1095:are Banach spaces, 504:{\displaystyle X,Y} 222:{\displaystyle X,Y} 96:{\displaystyle X,Y} 32:functional analysis 7254:Riemann hypothesis 6953:Topological vector 6719:(Pseudo)Metrizable 6551:Minkowski addition 6403:Sublinear function 6002:Unbounded operator 5931:Essential spectrum 5910:Schur–Horn theorem 5900:Bauer–Fike theorem 5895:Alon–Boppana bound 5888:Finite-Dimensional 5862:Nuclear C*-algebra 5706:Spectral asymmetry 5420:"Compact operator" 5138:10.1007/BF02392270 4807: 4688:That the operator 4678: 4627: 4525: 4454: 4414: 4343: 4279: 4263:tends to zero for 4253: 4213: 4175:, i.e., such that 4153: 4060: 4022: 3994: 3947: 3901: 3849: 3793: 3696: 3653: 3602: 3537:GĂ„rding inequality 3494:countably infinite 3452: 3385: 3349: 3314: 3234: 3205: 3177: 3156: 3136: 3101: 3072: 3037: 3005: 2984: 2950: 2681: 2652: 2616: 2590:then the range of 2580: 2551: 2525: 2499: 2464: 2437: 2416: 2395: 2373: 2351: 2330: 2279: 2244: 2193: 2140: 2108: 2083: 2062: 2026: 1998: 1972: 1943: 1919: 1892:Schauder's theorem 1870: 1847:forms a two-sided 1837: 1804: 1689: 1663: 1631: 1606: 1586: 1538: 1512: 1486: 1435: 1400: 1362: 1312: 1262: 1238: 1211: 1185: 1146: 1120: 1085: 1057:In the following, 1035: 1010: 988: 962: 937: 885: 864: 813: 778: 751: 730: 703: 690:relatively compact 677: 655: 630: 617:relatively compact 604: 582: 557: 533: 501: 471: 450: 420: 398: 369: 317:integral equations 277: 247: 219: 189: 165: 153:relatively compact 141: 117: 93: 67: 7331: 7330: 7234:Integral operator 7011: 7010: 6847: 6846: 6566:Relative interior 6312:Bilinear operator 6196:Linear functional 6132: 6131: 6109:Transfer operator 6084:Spectral geometry 5769:Spectral abscissa 5749:Approximate point 5691:Normal eigenvalue 5481: 5480: 5473: 5455: 5365:978-0-486-45352-1 5335:978-1-4612-7155-0 5301:978-0-07-054236-5 5272:978-0-387-00444-0 5214:978-0-471-55604-6 5192:978-0-7923-3898-7 5173:978-0-471-50731-4 5098:978-0-387-97245-9 5068:978-3-540-96042-3 4945:978-0-387-70914-7 4859:Fredholm operator 4835:Compact embedding 4387:weakly convergent 4251: 4173:nuclear operators 3605:{\displaystyle T} 3529:compact embedding 3180:{\displaystyle T} 3040:{\displaystyle X} 3008:{\displaystyle T} 2440:{\displaystyle N} 2419:{\displaystyle M} 2398:{\displaystyle X} 2384:are subspaces of 2376:{\displaystyle N} 2354:{\displaystyle M} 2291:Fredholm operator 2111:{\displaystyle X} 2098:Now suppose that 2086:{\displaystyle X} 2029:{\displaystyle X} 2001:{\displaystyle T} 1975:{\displaystyle T} 1946:{\displaystyle T} 1885:strictly singular 1634:{\displaystyle T} 1609:{\displaystyle T} 1265:{\displaystyle X} 1250:identity operator 1038:{\displaystyle Y} 1013:{\displaystyle T} 991:{\displaystyle X} 965:{\displaystyle Y} 888:{\displaystyle X} 754:{\displaystyle X} 740:of the origin in 733:{\displaystyle U} 706:{\displaystyle Y} 680:{\displaystyle T} 658:{\displaystyle X} 633:{\displaystyle Y} 607:{\displaystyle T} 585:{\displaystyle X} 560:{\displaystyle T} 474:{\displaystyle Y} 423:{\displaystyle X} 409:of the origin in 401:{\displaystyle U} 337:Fredholm operator 280:{\displaystyle Y} 250:{\displaystyle T} 192:{\displaystyle Y} 168:{\displaystyle Y} 144:{\displaystyle X} 120:{\displaystyle T} 16:(Redirected from 7361: 7349:Linear operators 7321: 7320: 7239:Jones polynomial 7157:Operator algebra 6901: 6874: 6867: 6860: 6851: 6837: 6836: 6811:Uniformly smooth 6480: 6472: 6439:Balanced/Circled 6429:Absorbing/Radial 6159: 6152: 6145: 6136: 6114:Transform theory 5834:Special algebras 5815:Spectral theorem 5778:Spectral Theorem 5618:Spectral theorem 5507: 5500: 5493: 5484: 5476: 5469: 5465: 5462: 5456: 5454: 5413: 5389: 5381: 5377: 5352:TrĂšves, François 5347: 5313: 5276: 5253: 5226: 5196: 5177: 5158: 5140: 5124:Acta Mathematica 5110: 5072: 5042: 5036: 5030: 5027: 5021: 5015: 5004: 4995:N.L. Carothers, 4993: 4987: 4981: 4958: 4957: 4929: 4920: 4914: 4908: 4903: 4897: 4891: 4864: 4850: 4816: 4814: 4813: 4808: 4803: 4767: 4766: 4687: 4685: 4684: 4679: 4671: 4640: 4635: 4534: 4532: 4531: 4526: 4524: 4523: 4463: 4461: 4460: 4455: 4450: 4449: 4423: 4421: 4420: 4415: 4410: 4409: 4352: 4350: 4349: 4344: 4336: 4331: 4330: 4321: 4315: 4310: 4288: 4286: 4285: 4280: 4262: 4260: 4259: 4254: 4252: 4244: 4239: 4238: 4222: 4220: 4219: 4214: 4203: 4195: 4162: 4160: 4159: 4154: 4152: 4151: 4133: 4132: 4120: 4119: 4109: 4104: 4069: 4067: 4066: 4061: 4031: 4029: 4028: 4023: 4021: 4003: 4001: 4000: 3995: 3987: 3986: 3956: 3954: 3953: 3948: 3940: 3939: 3927: 3926: 3910: 3908: 3907: 3902: 3891: 3890: 3878: 3877: 3858: 3856: 3855: 3850: 3839: 3838: 3826: 3825: 3802: 3800: 3799: 3794: 3792: 3791: 3773: 3772: 3760: 3759: 3749: 3744: 3705: 3703: 3702: 3697: 3695: 3694: 3685: 3684: 3662: 3660: 3659: 3654: 3631: 3630: 3611: 3609: 3608: 3603: 3561:quotient algebra 3461: 3459: 3458: 3453: 3394: 3392: 3391: 3386: 3384: 3383: 3358: 3356: 3355: 3350: 3323: 3321: 3320: 3315: 3313: 3309: 3302: 3294: 3260: 3259: 3243: 3241: 3240: 3235: 3214: 3212: 3211: 3206: 3204: 3203: 3186: 3184: 3183: 3178: 3165: 3163: 3162: 3157: 3145: 3143: 3142: 3137: 3110: 3108: 3107: 3102: 3081: 3079: 3078: 3073: 3046: 3044: 3043: 3038: 3014: 3012: 3011: 3006: 2993: 2991: 2990: 2985: 2959: 2957: 2956: 2951: 2949: 2948: 2942: 2938: 2937: 2936: 2935: 2934: 2914: 2913: 2893: 2888: 2887: 2878: 2877: 2862: 2858: 2857: 2856: 2855: 2854: 2834: 2833: 2804: 2803: 2797: 2793: 2792: 2791: 2762: 2754: 2753: 2738: 2734: 2733: 2732: 2690: 2688: 2687: 2682: 2661: 2659: 2658: 2653: 2651: 2650: 2625: 2623: 2622: 2617: 2615: 2614: 2589: 2587: 2586: 2581: 2560: 2558: 2557: 2552: 2534: 2532: 2531: 2526: 2508: 2506: 2505: 2500: 2473: 2471: 2470: 2465: 2446: 2444: 2443: 2438: 2425: 2423: 2422: 2417: 2404: 2402: 2401: 2396: 2382: 2380: 2379: 2374: 2360: 2358: 2357: 2352: 2339: 2337: 2336: 2331: 2320: 2319: 2318: 2288: 2286: 2285: 2280: 2272: 2271: 2270: 2253: 2251: 2250: 2245: 2202: 2200: 2199: 2194: 2192: 2191: 2179: 2178: 2166: 2165: 2149: 2147: 2146: 2141: 2117: 2115: 2114: 2109: 2092: 2090: 2089: 2084: 2071: 2069: 2068: 2063: 2035: 2033: 2032: 2027: 2007: 2005: 2004: 1999: 1981: 1979: 1978: 1973: 1961:if the range of 1952: 1950: 1949: 1944: 1928: 1926: 1925: 1920: 1879: 1877: 1876: 1871: 1846: 1844: 1843: 1838: 1813: 1811: 1810: 1805: 1698: 1696: 1695: 1690: 1672: 1670: 1669: 1664: 1642:is then compact. 1640: 1638: 1637: 1632: 1615: 1613: 1612: 1607: 1595: 1593: 1592: 1587: 1585: 1584: 1583: 1567: 1566: 1547: 1545: 1544: 1539: 1521: 1519: 1518: 1513: 1495: 1493: 1492: 1487: 1485: 1484: 1483: 1467: 1466: 1444: 1442: 1441: 1436: 1409: 1407: 1406: 1401: 1371: 1369: 1368: 1363: 1321: 1319: 1318: 1313: 1271: 1269: 1268: 1263: 1247: 1245: 1244: 1239: 1237: 1236: 1220: 1218: 1217: 1212: 1194: 1192: 1191: 1186: 1155: 1153: 1152: 1147: 1129: 1127: 1126: 1121: 1094: 1092: 1091: 1086: 1044: 1042: 1041: 1036: 1019: 1017: 1016: 1011: 997: 995: 994: 989: 971: 969: 968: 963: 946: 944: 943: 938: 936: 935: 934: 918: 917: 894: 892: 891: 886: 873: 871: 870: 865: 863: 862: 861: 845: 844: 822: 820: 819: 814: 787: 785: 784: 779: 760: 758: 757: 752: 739: 737: 736: 731: 712: 710: 709: 704: 686: 684: 683: 678: 664: 662: 661: 656: 639: 637: 636: 631: 613: 611: 610: 605: 591: 589: 588: 583: 566: 564: 563: 558: 542: 540: 539: 534: 510: 508: 507: 502: 480: 478: 477: 472: 459: 457: 456: 451: 429: 427: 426: 421: 407: 405: 404: 399: 378: 376: 375: 370: 286: 284: 283: 278: 258:that has finite 256: 254: 253: 248: 228: 226: 225: 220: 201:bounded operator 198: 196: 195: 190: 174: 172: 171: 166: 150: 148: 147: 142: 126: 124: 123: 118: 102: 100: 99: 94: 76: 74: 73: 68: 40:compact operator 21: 7369: 7368: 7364: 7363: 7362: 7360: 7359: 7358: 7354:Operator theory 7334: 7333: 7332: 7327: 7309: 7273:Advanced topics 7268: 7192: 7171: 7130: 7096:Hilbert–Schmidt 7069: 7060:Gelfand–Naimark 7007: 6957: 6892: 6878: 6848: 6843: 6825: 6587:B-complete/Ptak 6570: 6514: 6478: 6470: 6449:Bounding points 6412: 6354:Densely defined 6300: 6289:Bounded inverse 6235: 6169: 6163: 6133: 6128: 6089:Spectral method 6074:Ramanujan graph 6022: 6006: 5982:Fredholm theory 5950: 5945:Shilov boundary 5941:Structure space 5919:Generalizations 5914: 5905:Numerical range 5883: 5867:Uniform algebra 5829: 5805:Riesz projector 5790:Min-max theorem 5773: 5759:Direct integral 5715: 5701:Spectral radius 5672: 5627: 5581: 5572:Spectral radius 5520: 5514:Spectral theory 5511: 5477: 5466: 5460: 5457: 5414: 5412: 5402: 5390: 5366: 5350: 5336: 5316: 5302: 5280: 5273: 5265:. p. 356. 5263:Springer-Verlag 5256: 5242: 5229: 5215: 5199: 5193: 5180: 5174: 5161: 5113: 5099: 5089:Springer-Verlag 5077:Conway, John B. 5075: 5069: 5055:Conway, John B. 5053: 5050: 5045: 5037: 5033: 5028: 5024: 5016: 5007: 4994: 4990: 4982: 4961: 4946: 4931: 4930: 4923: 4915: 4911: 4904: 4900: 4892: 4885: 4881: 4862: 4848: 4831: 4758: 4729: 4728: 4598: 4597: 4564:For some fixed 4559: 4555: 4551: 4540: 4535:and a sequence 4515: 4510: 4509: 4502: 4441: 4430: 4429: 4428:, the sequence 4401: 4393: 4392: 4359: 4322: 4291: 4290: 4265: 4264: 4230: 4225: 4224: 4177: 4176: 4143: 4124: 4111: 4079: 4078: 4034: 4033: 4006: 4005: 3972: 3967: 3966: 3959:singular values 3931: 3918: 3913: 3912: 3882: 3869: 3861: 3860: 3830: 3817: 3809: 3808: 3783: 3764: 3751: 3719: 3718: 3668: 3667: 3617: 3616: 3594: 3593: 3587: 3581: 3563:, known as the 3420: 3419: 3410: 3375: 3361: 3360: 3326: 3325: 3268: 3264: 3251: 3246: 3245: 3220: 3219: 3195: 3190: 3189: 3169: 3168: 3148: 3147: 3113: 3112: 3087: 3086: 3049: 3048: 3029: 3028: 2997: 2996: 2967: 2966: 2926: 2921: 2905: 2904: 2900: 2879: 2846: 2841: 2825: 2824: 2820: 2783: 2773: 2769: 2724: 2714: 2710: 2693: 2692: 2667: 2666: 2642: 2628: 2627: 2606: 2592: 2591: 2566: 2565: 2537: 2536: 2511: 2510: 2479: 2478: 2474:is also closed. 2450: 2449: 2429: 2428: 2408: 2407: 2387: 2386: 2365: 2364: 2343: 2342: 2310: 2295: 2294: 2262: 2256: 2255: 2221: 2220: 2183: 2170: 2157: 2152: 2151: 2120: 2119: 2100: 2099: 2075: 2074: 2042: 2041: 2018: 2017: 1990: 1989: 1964: 1963: 1935: 1934: 1899: 1898: 1853: 1852: 1820: 1819: 1715: 1714: 1675: 1674: 1649: 1648: 1647:Conversely, if 1623: 1622: 1598: 1597: 1568: 1558: 1550: 1549: 1524: 1523: 1498: 1497: 1468: 1458: 1450: 1449: 1412: 1411: 1377: 1376: 1324: 1323: 1274: 1273: 1254: 1253: 1228: 1223: 1222: 1197: 1196: 1162: 1161: 1132: 1131: 1097: 1096: 1059: 1058: 1055: 1027: 1026: 1023:totally bounded 1002: 1001: 980: 979: 954: 953: 951:If in addition 919: 909: 898: 897: 896:, the sequence 877: 876: 846: 836: 828: 827: 790: 789: 764: 763: 743: 742: 722: 721: 717:there exists a 695: 694: 669: 668: 647: 646: 622: 621: 596: 595: 574: 573: 549: 548: 513: 512: 487: 486: 463: 462: 433: 432: 412: 411: 390: 389: 349: 348: 345: 329:function spaces 269: 268: 239: 238: 205: 204: 181: 180: 157: 156: 133: 132: 129:bounded subsets 109: 108: 79: 78: 47: 46: 44:linear operator 28: 23: 22: 15: 12: 11: 5: 7367: 7365: 7357: 7356: 7351: 7346: 7336: 7335: 7329: 7328: 7326: 7325: 7314: 7311: 7310: 7308: 7307: 7302: 7297: 7292: 7290:Choquet theory 7287: 7282: 7276: 7274: 7270: 7269: 7267: 7266: 7256: 7251: 7246: 7241: 7236: 7231: 7226: 7221: 7216: 7211: 7206: 7200: 7198: 7194: 7193: 7191: 7190: 7185: 7179: 7177: 7173: 7172: 7170: 7169: 7164: 7159: 7154: 7149: 7144: 7142:Banach algebra 7138: 7136: 7132: 7131: 7129: 7128: 7123: 7118: 7113: 7108: 7103: 7098: 7093: 7088: 7083: 7077: 7075: 7071: 7070: 7068: 7067: 7065:Banach–Alaoglu 7062: 7057: 7052: 7047: 7042: 7037: 7032: 7027: 7021: 7019: 7013: 7012: 7009: 7008: 7006: 7005: 7000: 6995: 6993:Locally convex 6990: 6976: 6971: 6965: 6963: 6959: 6958: 6956: 6955: 6950: 6945: 6940: 6935: 6930: 6925: 6920: 6915: 6910: 6904: 6898: 6894: 6893: 6879: 6877: 6876: 6869: 6862: 6854: 6845: 6844: 6842: 6841: 6830: 6827: 6826: 6824: 6823: 6818: 6813: 6808: 6806:Ultrabarrelled 6798: 6792: 6787: 6781: 6776: 6771: 6766: 6761: 6756: 6747: 6741: 6736: 6734:Quasi-complete 6731: 6729:Quasibarrelled 6726: 6721: 6716: 6711: 6706: 6701: 6696: 6691: 6686: 6681: 6676: 6671: 6670: 6669: 6659: 6654: 6649: 6644: 6639: 6634: 6629: 6624: 6619: 6609: 6604: 6594: 6589: 6584: 6578: 6576: 6572: 6571: 6569: 6568: 6558: 6553: 6548: 6543: 6538: 6528: 6522: 6520: 6519:Set operations 6516: 6515: 6513: 6512: 6507: 6502: 6497: 6492: 6487: 6482: 6474: 6466: 6461: 6456: 6451: 6446: 6441: 6436: 6431: 6426: 6420: 6418: 6414: 6413: 6411: 6410: 6405: 6400: 6395: 6390: 6389: 6388: 6383: 6378: 6368: 6363: 6362: 6361: 6356: 6351: 6346: 6341: 6336: 6331: 6321: 6320: 6319: 6308: 6306: 6302: 6301: 6299: 6298: 6293: 6292: 6291: 6281: 6275: 6266: 6261: 6256: 6254:Banach–Alaoglu 6251: 6249:Anderson–Kadec 6245: 6243: 6237: 6236: 6234: 6233: 6228: 6223: 6218: 6213: 6208: 6203: 6198: 6193: 6188: 6183: 6177: 6175: 6174:Basic concepts 6171: 6170: 6164: 6162: 6161: 6154: 6147: 6139: 6130: 6129: 6127: 6126: 6121: 6116: 6111: 6106: 6101: 6096: 6091: 6086: 6081: 6076: 6071: 6066: 6061: 6056: 6051: 6041: 6039:Corona theorem 6036: 6030: 6028: 6024: 6023: 6021: 6020: 6018:Wiener algebra 6014: 6012: 6008: 6007: 6005: 6004: 5999: 5994: 5989: 5984: 5979: 5974: 5969: 5964: 5958: 5956: 5952: 5951: 5949: 5948: 5938: 5936:Pseudospectrum 5933: 5928: 5926:Dirac spectrum 5922: 5920: 5916: 5915: 5913: 5912: 5907: 5902: 5897: 5891: 5889: 5885: 5884: 5882: 5881: 5880: 5879: 5869: 5864: 5859: 5854: 5849: 5843: 5837: 5835: 5831: 5830: 5828: 5827: 5822: 5817: 5812: 5807: 5802: 5797: 5792: 5787: 5781: 5779: 5775: 5774: 5772: 5771: 5766: 5761: 5756: 5751: 5746: 5745: 5744: 5739: 5734: 5723: 5721: 5717: 5716: 5714: 5713: 5708: 5703: 5698: 5693: 5688: 5682: 5680: 5674: 5673: 5671: 5670: 5665: 5657: 5649: 5641: 5635: 5633: 5629: 5628: 5626: 5625: 5620: 5615: 5610: 5605: 5600: 5595: 5589: 5587: 5583: 5582: 5580: 5579: 5577:Operator space 5574: 5569: 5564: 5559: 5554: 5549: 5544: 5539: 5537:Banach algebra 5534: 5528: 5526: 5525:Basic concepts 5522: 5521: 5512: 5510: 5509: 5502: 5495: 5487: 5479: 5478: 5393: 5391: 5384: 5379: 5378: 5364: 5348: 5334: 5314: 5300: 5278: 5271: 5254: 5241:978-1584888666 5240: 5227: 5213: 5197: 5191: 5178: 5172: 5159: 5131:(1): 309–317. 5111: 5097: 5073: 5067: 5049: 5046: 5044: 5043: 5031: 5022: 5005: 4988: 4959: 4944: 4921: 4909: 4898: 4882: 4880: 4877: 4876: 4875: 4870: 4865: 4856: 4851: 4842: 4837: 4830: 4827: 4826: 4825: 4818: 4806: 4802: 4797: 4794: 4791: 4788: 4785: 4782: 4779: 4776: 4773: 4770: 4765: 4761: 4757: 4754: 4751: 4748: 4745: 4742: 4739: 4736: 4697: 4694:Ascoli theorem 4677: 4674: 4670: 4665: 4662: 4659: 4656: 4653: 4650: 4647: 4644: 4639: 4634: 4630: 4626: 4623: 4620: 4617: 4614: 4611: 4608: 4605: 4562: 4557: 4553: 4549: 4538: 4522: 4518: 4506: 4501: 4498: 4453: 4448: 4444: 4440: 4437: 4413: 4408: 4404: 4400: 4385:if, for every 4358: 4355: 4342: 4339: 4335: 4329: 4325: 4320: 4314: 4309: 4306: 4303: 4299: 4278: 4275: 4272: 4250: 4247: 4242: 4237: 4233: 4212: 4209: 4206: 4202: 4198: 4194: 4190: 4187: 4184: 4165: 4164: 4150: 4146: 4142: 4139: 4136: 4131: 4127: 4123: 4118: 4114: 4108: 4103: 4100: 4097: 4093: 4089: 4086: 4059: 4056: 4053: 4050: 4047: 4044: 4041: 4020: 4016: 4013: 3993: 3990: 3985: 3982: 3979: 3975: 3946: 3943: 3938: 3934: 3930: 3925: 3921: 3900: 3897: 3894: 3889: 3885: 3881: 3876: 3872: 3868: 3848: 3845: 3842: 3837: 3833: 3829: 3824: 3820: 3816: 3805: 3804: 3790: 3786: 3782: 3779: 3776: 3771: 3767: 3763: 3758: 3754: 3748: 3743: 3740: 3737: 3733: 3729: 3726: 3710:is said to be 3708: 3707: 3693: 3688: 3683: 3678: 3675: 3652: 3649: 3646: 3643: 3640: 3637: 3634: 3629: 3624: 3601: 3583:Main article: 3580: 3577: 3573:operator ideal 3565:Calkin algebra 3533:Sobolev spaces 3451: 3448: 3445: 3442: 3439: 3436: 3433: 3430: 3427: 3409: 3406: 3405: 3404: 3382: 3378: 3374: 3371: 3368: 3348: 3345: 3342: 3339: 3336: 3333: 3312: 3308: 3305: 3301: 3297: 3293: 3289: 3286: 3283: 3280: 3277: 3274: 3271: 3267: 3263: 3258: 3254: 3233: 3230: 3227: 3216: 3202: 3198: 3176: 3155: 3135: 3132: 3129: 3126: 3123: 3120: 3100: 3097: 3094: 3083: 3071: 3068: 3065: 3062: 3059: 3056: 3036: 3025: 3004: 2983: 2980: 2977: 2974: 2960: 2947: 2941: 2933: 2929: 2924: 2920: 2917: 2912: 2908: 2903: 2899: 2896: 2892: 2886: 2882: 2876: 2871: 2868: 2865: 2861: 2853: 2849: 2844: 2840: 2837: 2832: 2828: 2823: 2819: 2816: 2813: 2810: 2807: 2802: 2796: 2790: 2786: 2782: 2779: 2776: 2772: 2768: 2765: 2761: 2757: 2752: 2747: 2744: 2741: 2737: 2731: 2727: 2723: 2720: 2717: 2713: 2709: 2706: 2703: 2700: 2680: 2677: 2674: 2663: 2649: 2645: 2641: 2638: 2635: 2613: 2609: 2605: 2602: 2599: 2579: 2576: 2573: 2562: 2550: 2547: 2544: 2524: 2521: 2518: 2498: 2495: 2492: 2489: 2486: 2475: 2463: 2460: 2457: 2436: 2426:is closed and 2415: 2394: 2372: 2350: 2329: 2326: 2323: 2317: 2313: 2308: 2305: 2302: 2278: 2275: 2269: 2265: 2243: 2240: 2237: 2234: 2231: 2228: 2190: 2186: 2182: 2177: 2173: 2169: 2164: 2160: 2139: 2136: 2133: 2130: 2127: 2107: 2096: 2095: 2082: 2061: 2058: 2055: 2052: 2049: 2025: 2014: 2013: 2012: 2011: 2010: 1997: 1971: 1959: 1942: 1918: 1915: 1912: 1909: 1906: 1888: 1881: 1869: 1866: 1863: 1860: 1836: 1833: 1830: 1827: 1803: 1800: 1797: 1794: 1791: 1788: 1785: 1782: 1779: 1776: 1773: 1770: 1767: 1764: 1761: 1758: 1755: 1752: 1749: 1746: 1743: 1740: 1737: 1734: 1731: 1728: 1725: 1722: 1712: 1688: 1685: 1682: 1662: 1659: 1656: 1645: 1644: 1643: 1630: 1605: 1582: 1578: 1575: 1571: 1565: 1561: 1557: 1537: 1534: 1531: 1511: 1508: 1505: 1482: 1478: 1475: 1471: 1465: 1461: 1457: 1434: 1431: 1428: 1425: 1422: 1419: 1399: 1396: 1393: 1390: 1387: 1384: 1361: 1358: 1355: 1352: 1349: 1346: 1343: 1340: 1337: 1334: 1331: 1311: 1308: 1305: 1302: 1299: 1296: 1293: 1290: 1287: 1284: 1281: 1261: 1235: 1231: 1210: 1207: 1204: 1184: 1181: 1178: 1175: 1172: 1169: 1145: 1142: 1139: 1119: 1116: 1113: 1110: 1107: 1104: 1084: 1081: 1078: 1075: 1072: 1069: 1066: 1054: 1051: 1047: 1046: 1034: 1009: 987: 961: 949: 948: 933: 929: 926: 922: 916: 912: 908: 905: 884: 860: 856: 853: 849: 843: 839: 835: 824: 812: 809: 806: 803: 800: 797: 777: 774: 771: 750: 729: 715: 702: 676: 654: 642: 629: 603: 581: 569: 556: 532: 529: 526: 523: 520: 500: 497: 494: 470: 449: 446: 443: 440: 419: 397: 383:is said to be 368: 365: 362: 359: 356: 344: 341: 333:equicontinuity 276: 246: 218: 215: 212: 188: 164: 140: 116: 92: 89: 86: 66: 63: 60: 57: 54: 34:, a branch of 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 7366: 7355: 7352: 7350: 7347: 7345: 7342: 7341: 7339: 7324: 7316: 7315: 7312: 7306: 7303: 7301: 7298: 7296: 7295:Weak topology 7293: 7291: 7288: 7286: 7283: 7281: 7278: 7277: 7275: 7271: 7264: 7260: 7257: 7255: 7252: 7250: 7247: 7245: 7242: 7240: 7237: 7235: 7232: 7230: 7227: 7225: 7222: 7220: 7219:Index theorem 7217: 7215: 7212: 7210: 7207: 7205: 7202: 7201: 7199: 7195: 7189: 7186: 7184: 7181: 7180: 7178: 7176:Open problems 7174: 7168: 7165: 7163: 7160: 7158: 7155: 7153: 7150: 7148: 7145: 7143: 7140: 7139: 7137: 7133: 7127: 7124: 7122: 7119: 7117: 7114: 7112: 7109: 7107: 7104: 7102: 7099: 7097: 7094: 7092: 7089: 7087: 7084: 7082: 7079: 7078: 7076: 7072: 7066: 7063: 7061: 7058: 7056: 7053: 7051: 7048: 7046: 7043: 7041: 7038: 7036: 7033: 7031: 7028: 7026: 7023: 7022: 7020: 7018: 7014: 7004: 7001: 6999: 6996: 6994: 6991: 6988: 6984: 6980: 6977: 6975: 6972: 6970: 6967: 6966: 6964: 6960: 6954: 6951: 6949: 6946: 6944: 6941: 6939: 6936: 6934: 6931: 6929: 6926: 6924: 6921: 6919: 6916: 6914: 6911: 6909: 6906: 6905: 6902: 6899: 6895: 6890: 6886: 6882: 6875: 6870: 6868: 6863: 6861: 6856: 6855: 6852: 6840: 6832: 6831: 6828: 6822: 6819: 6817: 6814: 6812: 6809: 6807: 6803: 6799: 6797:) convex 6796: 6793: 6791: 6788: 6786: 6782: 6780: 6777: 6775: 6772: 6770: 6769:Semi-complete 6767: 6765: 6762: 6760: 6757: 6755: 6751: 6748: 6746: 6742: 6740: 6737: 6735: 6732: 6730: 6727: 6725: 6722: 6720: 6717: 6715: 6712: 6710: 6707: 6705: 6702: 6700: 6697: 6695: 6692: 6690: 6687: 6685: 6684:Infrabarreled 6682: 6680: 6677: 6675: 6672: 6668: 6665: 6664: 6663: 6660: 6658: 6655: 6653: 6650: 6648: 6645: 6643: 6642:Distinguished 6640: 6638: 6635: 6633: 6630: 6628: 6625: 6623: 6620: 6618: 6614: 6610: 6608: 6605: 6603: 6599: 6595: 6593: 6590: 6588: 6585: 6583: 6580: 6579: 6577: 6575:Types of TVSs 6573: 6567: 6563: 6559: 6557: 6554: 6552: 6549: 6547: 6544: 6542: 6539: 6537: 6533: 6529: 6527: 6524: 6523: 6521: 6517: 6511: 6508: 6506: 6503: 6501: 6498: 6496: 6495:Prevalent/Shy 6493: 6491: 6488: 6486: 6485:Extreme point 6483: 6481: 6475: 6473: 6467: 6465: 6462: 6460: 6457: 6455: 6452: 6450: 6447: 6445: 6442: 6440: 6437: 6435: 6432: 6430: 6427: 6425: 6422: 6421: 6419: 6417:Types of sets 6415: 6409: 6406: 6404: 6401: 6399: 6396: 6394: 6391: 6387: 6384: 6382: 6379: 6377: 6374: 6373: 6372: 6369: 6367: 6364: 6360: 6359:Discontinuous 6357: 6355: 6352: 6350: 6347: 6345: 6342: 6340: 6337: 6335: 6332: 6330: 6327: 6326: 6325: 6322: 6318: 6315: 6314: 6313: 6310: 6309: 6307: 6303: 6297: 6294: 6290: 6287: 6286: 6285: 6282: 6279: 6276: 6274: 6270: 6267: 6265: 6262: 6260: 6257: 6255: 6252: 6250: 6247: 6246: 6244: 6242: 6238: 6232: 6229: 6227: 6224: 6222: 6219: 6217: 6216:Metrizability 6214: 6212: 6209: 6207: 6204: 6202: 6201:FrĂ©chet space 6199: 6197: 6194: 6192: 6189: 6187: 6184: 6182: 6179: 6178: 6176: 6172: 6167: 6160: 6155: 6153: 6148: 6146: 6141: 6140: 6137: 6125: 6122: 6120: 6117: 6115: 6112: 6110: 6107: 6105: 6102: 6100: 6097: 6095: 6092: 6090: 6087: 6085: 6082: 6080: 6077: 6075: 6072: 6070: 6067: 6065: 6062: 6060: 6057: 6055: 6052: 6049: 6045: 6042: 6040: 6037: 6035: 6032: 6031: 6029: 6025: 6019: 6016: 6015: 6013: 6009: 6003: 6000: 5998: 5995: 5993: 5990: 5988: 5985: 5983: 5980: 5978: 5975: 5973: 5970: 5968: 5965: 5963: 5960: 5959: 5957: 5955:Miscellaneous 5953: 5946: 5942: 5939: 5937: 5934: 5932: 5929: 5927: 5924: 5923: 5921: 5917: 5911: 5908: 5906: 5903: 5901: 5898: 5896: 5893: 5892: 5890: 5886: 5878: 5875: 5874: 5873: 5870: 5868: 5865: 5863: 5860: 5858: 5855: 5853: 5850: 5848: 5844: 5842: 5839: 5838: 5836: 5832: 5826: 5823: 5821: 5818: 5816: 5813: 5811: 5808: 5806: 5803: 5801: 5798: 5796: 5793: 5791: 5788: 5786: 5783: 5782: 5780: 5776: 5770: 5767: 5765: 5762: 5760: 5757: 5755: 5752: 5750: 5747: 5743: 5740: 5738: 5735: 5733: 5730: 5729: 5728: 5725: 5724: 5722: 5720:Decomposition 5718: 5712: 5709: 5707: 5704: 5702: 5699: 5697: 5694: 5692: 5689: 5687: 5684: 5683: 5681: 5679: 5675: 5669: 5666: 5664: 5661: 5658: 5656: 5653: 5650: 5648: 5645: 5642: 5640: 5637: 5636: 5634: 5630: 5624: 5621: 5619: 5616: 5614: 5611: 5609: 5606: 5604: 5601: 5599: 5596: 5594: 5591: 5590: 5588: 5584: 5578: 5575: 5573: 5570: 5568: 5565: 5563: 5560: 5558: 5555: 5553: 5550: 5548: 5545: 5543: 5540: 5538: 5535: 5533: 5530: 5529: 5527: 5523: 5519: 5515: 5508: 5503: 5501: 5496: 5494: 5489: 5488: 5485: 5475: 5472: 5464: 5453: 5450: 5446: 5443: 5439: 5436: 5432: 5429: 5425: 5422: â€“  5421: 5417: 5416:Find sources: 5410: 5406: 5400: 5399: 5394:This article 5392: 5388: 5383: 5382: 5375: 5371: 5367: 5361: 5357: 5353: 5349: 5345: 5341: 5337: 5331: 5327: 5323: 5319: 5315: 5311: 5307: 5303: 5297: 5293: 5289: 5288: 5283: 5282:Rudin, Walter 5279: 5277:(Section 7.5) 5274: 5268: 5264: 5260: 5255: 5251: 5247: 5243: 5237: 5233: 5228: 5224: 5220: 5216: 5210: 5206: 5202: 5198: 5194: 5188: 5184: 5179: 5175: 5169: 5165: 5160: 5156: 5152: 5148: 5144: 5139: 5134: 5130: 5126: 5125: 5120: 5116: 5112: 5108: 5104: 5100: 5094: 5090: 5086: 5082: 5078: 5074: 5070: 5064: 5060: 5056: 5052: 5051: 5047: 5040: 5039:Kreyszig 1978 5035: 5032: 5026: 5023: 5019: 5014: 5012: 5010: 5006: 5002: 4998: 4992: 4989: 4985: 4980: 4978: 4976: 4974: 4972: 4970: 4968: 4966: 4964: 4960: 4955: 4951: 4947: 4941: 4937: 4936: 4928: 4926: 4922: 4919:, p. 98. 4918: 4913: 4910: 4907: 4902: 4899: 4896:, Section 2.4 4895: 4890: 4888: 4884: 4878: 4874: 4871: 4869: 4866: 4860: 4857: 4855: 4852: 4846: 4843: 4841: 4838: 4836: 4833: 4832: 4828: 4823: 4822:Riesz's lemma 4819: 4804: 4792: 4786: 4780: 4777: 4774: 4768: 4759: 4755: 4749: 4740: 4737: 4727:) defined by 4726: 4722: 4718: 4714: 4710: 4706: 4702: 4698: 4695: 4691: 4675: 4672: 4660: 4654: 4648: 4642: 4637: 4632: 4628: 4624: 4618: 4609: 4606: 4595: 4591: 4587: 4583: 4579: 4575: 4571: 4568: âˆˆ  4567: 4563: 4560: 4546: 4542: 4520: 4516: 4507: 4504: 4503: 4499: 4497: 4493: 4491: 4487: 4483: 4479: 4475: 4471: 4467: 4446: 4442: 4438: 4427: 4406: 4402: 4391: 4388: 4384: 4380: 4376: 4372: 4368: 4364: 4356: 4354: 4337: 4327: 4323: 4307: 4304: 4301: 4297: 4270: 4248: 4245: 4240: 4235: 4231: 4207: 4196: 4185: 4182: 4174: 4170: 4148: 4144: 4137: 4134: 4129: 4125: 4116: 4112: 4106: 4101: 4098: 4095: 4091: 4087: 4084: 4077: 4076: 4075: 4073: 4057: 4054: 4051: 4048: 4045: 4042: 4039: 4014: 4011: 3991: 3988: 3983: 3980: 3977: 3973: 3964: 3960: 3944: 3941: 3936: 3932: 3928: 3923: 3919: 3895: 3892: 3887: 3883: 3879: 3874: 3870: 3843: 3840: 3835: 3831: 3827: 3822: 3818: 3788: 3784: 3777: 3774: 3769: 3765: 3756: 3752: 3741: 3738: 3735: 3731: 3727: 3724: 3717: 3716: 3715: 3713: 3676: 3673: 3666: 3665: 3664: 3644: 3641: 3638: 3632: 3615: 3614:Hilbert space 3599: 3590: 3586: 3578: 3576: 3574: 3570: 3566: 3562: 3558: 3554: 3549: 3546: 3542: 3538: 3534: 3530: 3525: 3523: 3519: 3515: 3511: 3507: 3503: 3499: 3495: 3491: 3487: 3483: 3482:Frigyes Riesz 3479: 3475: 3471: 3467: 3462: 3449: 3446: 3443: 3437: 3434: 3431: 3428: 3417: 3415: 3407: 3402: 3398: 3397:proper subset 3380: 3376: 3372: 3369: 3366: 3359:the range of 3343: 3337: 3334: 3331: 3310: 3306: 3303: 3295: 3287: 3281: 3275: 3272: 3269: 3265: 3261: 3256: 3252: 3231: 3228: 3225: 3217: 3200: 3196: 3187: 3174: 3153: 3130: 3124: 3121: 3118: 3098: 3095: 3092: 3084: 3066: 3060: 3057: 3054: 3034: 3026: 3023: 3019: 3015: 3002: 2978: 2972: 2965: 2961: 2939: 2931: 2927: 2922: 2918: 2915: 2910: 2906: 2901: 2897: 2894: 2890: 2884: 2880: 2869: 2866: 2863: 2859: 2851: 2847: 2842: 2838: 2835: 2830: 2826: 2821: 2817: 2814: 2811: 2808: 2805: 2794: 2788: 2784: 2780: 2777: 2774: 2770: 2766: 2763: 2759: 2755: 2745: 2742: 2739: 2735: 2729: 2725: 2721: 2718: 2715: 2711: 2707: 2704: 2701: 2698: 2678: 2675: 2672: 2664: 2647: 2643: 2639: 2636: 2633: 2611: 2607: 2603: 2600: 2597: 2577: 2574: 2571: 2563: 2548: 2545: 2542: 2522: 2519: 2516: 2496: 2490: 2487: 2484: 2476: 2461: 2458: 2455: 2447: 2434: 2413: 2405: 2392: 2383: 2370: 2361: 2348: 2324: 2321: 2315: 2311: 2303: 2300: 2292: 2289:  is a 2276: 2273: 2267: 2263: 2238: 2232: 2229: 2226: 2218: 2217: 2216: 2214: 2210: 2206: 2188: 2184: 2175: 2171: 2167: 2162: 2158: 2137: 2131: 2128: 2125: 2105: 2093: 2080: 2059: 2053: 2050: 2047: 2039: 2023: 2015: 2008: 1995: 1986: 1983:is closed in 1982: 1969: 1960: 1957: 1953: 1940: 1931: 1930: 1916: 1910: 1907: 1904: 1896: 1895: 1893: 1889: 1886: 1882: 1864: 1858: 1850: 1831: 1825: 1817: 1801: 1795: 1792: 1789: 1783: 1780: 1774: 1771: 1768: 1762: 1759: 1753: 1750: 1747: 1741: 1738: 1732: 1729: 1726: 1720: 1713: 1710: 1706: 1702: 1686: 1680: 1660: 1657: 1654: 1646: 1641: 1628: 1619: 1618:operator norm 1603: 1596:converges to 1576: 1573: 1563: 1559: 1535: 1532: 1529: 1509: 1503: 1476: 1473: 1463: 1459: 1447: 1446: 1429: 1426: 1423: 1417: 1394: 1391: 1388: 1382: 1375: 1374: 1373: 1356: 1353: 1350: 1344: 1341: 1335: 1329: 1306: 1303: 1300: 1294: 1291: 1285: 1279: 1259: 1251: 1233: 1229: 1208: 1202: 1179: 1176: 1173: 1167: 1159: 1158:operator norm 1143: 1137: 1114: 1111: 1108: 1102: 1082: 1079: 1076: 1073: 1070: 1067: 1064: 1052: 1050: 1032: 1024: 1020: 1007: 998: 985: 976: 975: 974: 972: 959: 927: 924: 914: 910: 906: 895: 882: 854: 851: 841: 837: 825: 810: 807: 801: 795: 775: 772: 769: 761: 748: 727: 720: 719:neighbourhood 716: 713: 700: 691: 687: 674: 665: 652: 643: 640: 627: 618: 614: 601: 592: 579: 570: 567: 554: 546: 545: 544: 530: 524: 521: 518: 498: 495: 492: 483: 481: 468: 444: 438: 430: 417: 408: 395: 386: 382: 366: 360: 357: 354: 347:A linear map 342: 340: 338: 334: 330: 326: 322: 318: 313: 311: 307: 303: 299: 295: 294:norm topology 291: 290:Hilbert space 287: 274: 265: 261: 257: 244: 234: 232: 216: 213: 210: 202: 186: 178: 162: 154: 138: 130: 114: 106: 90: 87: 84: 64: 58: 55: 52: 45: 41: 37: 33: 19: 7285:Balanced set 7259:Distribution 7197:Applications 7090: 7050:Krein–Milman 7035:Closed graph 6745:Polynomially 6674:Grothendieck 6667:tame FrĂ©chet 6617:Bornological 6477:Linear cone 6469:Convex cone 6444:Banach disks 6386:Sesquilinear 6348: 6241:Main results 6231:Vector space 6186:Completeness 6181:Banach space 6027:Applications 5857:Disk algebra 5711:Spectral gap 5586:Main results 5467: 5458: 5448: 5441: 5434: 5427: 5415: 5403:Please help 5398:verification 5395: 5355: 5321: 5286: 5258: 5231: 5204: 5182: 5163: 5128: 5122: 5080: 5058: 5034: 5025: 5000: 4996: 4991: 4934: 4912: 4901: 4724: 4720: 4716: 4708: 4704: 4700: 4689: 4593: 4589: 4585: 4581: 4577: 4573: 4569: 4565: 4548: 4544: 4536: 4494: 4492:is compact. 4489: 4485: 4481: 4473: 4465: 4425: 4382: 4378: 4374: 4370: 4366: 4362: 4360: 4166: 4071: 3806: 3711: 3709: 3592:An operator 3591: 3588: 3550: 3526: 3517: 3513: 3509: 3497: 3489: 3485: 3473: 3469: 3465: 3463: 3418: 3411: 3400: 3167: 3016:is compact, 2995: 2427: 2385: 2363: 2341: 2212: 2097: 2073: 1988: 1984: 1962: 1933: 1891: 1708: 1704: 1621: 1248:denotes the 1056: 1048: 1000: 978: 952: 950: 875: 741: 693: 667: 645: 620: 594: 572: 547: 484: 461: 410: 388: 384: 379:between two 346: 324: 314: 306:Grothendieck 267: 237: 235: 39: 29: 7214:Heat kernel 7204:Hardy space 7111:Trace class 7025:Hahn–Banach 6987:Topological 6739:Quasinormed 6652:FK-AK space 6546:Linear span 6541:Convex hull 6526:Affine hull 6329:Almost open 6269:Hahn–Banach 6054:Heat kernel 5754:Compression 5639:Isospectral 5018:Conway 1990 4894:Conway 1985 4561:is compact. 4470:Conway 1985 4169:trace-class 3506:eigenvalues 3502:limit point 3022:limit point 1816:composition 155:subsets of 36:mathematics 7338:Categories 7147:C*-algebra 6962:Properties 6779:Stereotype 6637:(DF)-space 6632:Convenient 6371:Functional 6339:Continuous 6324:Linear map 6264:F. Riesz's 6206:Linear map 5732:Continuous 5547:C*-algebra 5542:B*-algebra 5431:newspapers 5201:Lax, Peter 5048:References 4984:Rudin 1991 4906:Enflo 1973 4381:is called 4032:and every 3963:accumulate 3496:subset of 3218:For every 2038:invertible 1814:where the 1156:under the 1053:Properties 788:such that 431:such that 7121:Unbounded 7116:Transpose 7074:Operators 7003:Separable 6998:Reflexive 6983:Algebraic 6969:Barrelled 6795:Uniformly 6754:Reflexive 6602:Barrelled 6598:Countably 6510:Symmetric 6408:Transpose 5518:-algebras 5374:853623322 5354:(2006) . 5344:840278135 5250:144216834 5147:0001-5962 5115:Enflo, P. 4954:695395895 4764:Ω 4760:∫ 4723:(Ω;  4629:∫ 4517:ℓ 4341:∞ 4324:λ 4313:∞ 4298:∑ 4277:∞ 4274:→ 4232:λ 4211:∞ 4186:⁡ 4141:⟩ 4138:⋅ 4122:⟨ 4113:λ 4092:∑ 4058:… 4015:∈ 4004:for some 3974:λ 3945:… 3933:λ 3920:λ 3896:… 3844:… 3781:⟩ 3778:⋅ 3762:⟨ 3753:λ 3747:∞ 3732:∑ 3687:→ 3677:: 3648:⟩ 3645:⋅ 3639:⋅ 3636:⟨ 3429:λ 3373:λ 3370:− 3338:σ 3335:∈ 3332:λ 3296:λ 3276:σ 3273:∈ 3270:λ 3201:∗ 3154:λ 3125:σ 3122:∈ 3119:λ 3096:≠ 3093:λ 3061:σ 3058:∈ 3018:countable 2973:σ 2932:∗ 2919:λ 2916:− 2911:∗ 2898:⁡ 2885:∗ 2870:⁡ 2852:∗ 2839:λ 2836:− 2831:∗ 2818:⁡ 2812:⁡ 2781:λ 2778:− 2767:⁡ 2746:⁡ 2722:λ 2719:− 2708:⁡ 2702:⁡ 2676:≠ 2673:λ 2640:λ 2637:− 2604:λ 2601:− 2575:≠ 2572:λ 2546:∘ 2520:∘ 2494:→ 2488:: 2322:− 2304:⁡ 2274:− 2230:∈ 2209:transpose 2189:∗ 2181:→ 2176:∗ 2168:: 2163:∗ 2135:→ 2129:: 2057:→ 1956:separable 1914:→ 1781:⊆ 1760:∘ 1739:∘ 1684:→ 1577:∈ 1507:→ 1477:∈ 1206:→ 1141:→ 928:∈ 855:∈ 808:⊆ 773:⊆ 528:→ 364:→ 302:Per Enflo 62:→ 7323:Category 7135:Algebras 7017:Theorems 6974:Complete 6943:Schwartz 6889:glossary 6839:Category 6790:Strictly 6764:Schwartz 6704:LF-space 6699:LB-space 6657:FK-space 6627:Complete 6607:BK-space 6532:Relative 6479:(subset) 6471:(subset) 6398:Seminorm 6381:Bilinear 6119:Weyl law 6064:Lax pair 6011:Examples 5845:With an 5764:Discrete 5742:Residual 5678:Spectrum 5663:operator 5655:operator 5647:operator 5562:Spectrum 5461:May 2008 5310:21163277 5284:(1991). 5223:47767143 5203:(2002). 5117:(1973). 5107:21195908 5079:(1990). 5057:(1985). 4829:See also 4592:(;  4584:(;  4572:(;  4500:Examples 4484: : 4390:sequence 4373: : 3539:and the 3244:the set 2964:spectrum 2219:For any 1496:mapping 77:, where 7126:Unitary 7106:Nuclear 7091:Compact 7086:Bounded 7081:Adjoint 7055:Min–max 6948:Sobolev 6933:Nuclear 6923:Hilbert 6918:FrĂ©chet 6883: ( 6804:)  6752:)  6694:K-space 6679:Hilbert 6662:FrĂ©chet 6647:F-space 6622:Brauner 6615:)  6600:)  6582:Asplund 6564:)  6534:)  6454:Bounded 6349:Compact 6334:Bounded 6271: ( 5660:Unitary 5445:scholar 5155:0402468 3712:compact 3557:algebra 3555:in the 3464:(where 2205:adjoint 2203:is the 1522:(where 385:compact 177:closure 7101:Normal 6938:Orlicz 6928:Hölder 6908:Banach 6897:Spaces 6885:topics 6816:Webbed 6802:Quasi- 6724:Montel 6714:Mackey 6613:Ultra- 6592:Banach 6500:Radial 6464:Convex 6434:Affine 6376:Linear 6344:Closed 6168:(TVSs) 5644:Normal 5447:  5440:  5433:  5426:  5418:  5372:  5362:  5342:  5332:  5308:  5298:  5269:  5248:  5238:  5221:  5211:  5189:  5170:  5153:  5145:  5105:  5095:  5065:  4952:  4942:  4289:while 3807:where 3569:simple 3522:kernel 2406:where 1322:, and 1160:, and 999:under 666:under 593:under 310:Banach 231:Banach 6913:Besov 6774:Smith 6759:Riesz 6750:Semi- 6562:Quasi 6556:Polar 5737:Point 5452:JSTOR 5438:books 4879:Notes 4711:is a 4596:) by 4588:) to 4580:from 4476:is a 4424:from 3567:, is 3553:ideal 3395:is a 3146:then 2072:then 1849:ideal 288:is a 127:maps 42:is a 7261:(or 6979:Dual 6393:Norm 6317:form 6305:Maps 5668:Unit 5516:and 5424:news 5370:OCLC 5360:ISBN 5340:OCLC 5330:ISBN 5306:OCLC 5296:ISBN 5267:ISBN 5246:OCLC 5236:ISBN 5219:OCLC 5209:ISBN 5187:ISBN 5168:ISBN 5143:ISSN 5103:OCLC 5093:ISBN 5063:ISBN 4950:OCLC 4940:ISBN 4508:For 4365:and 4361:Let 4208:< 4072:i.e. 3859:and 3304:> 3229:> 3188:and 3111:and 2962:The 2535:and 2362:and 1707:and 485:Let 308:and 260:rank 229:are 103:are 38:, a 5407:by 5326:GTM 5133:doi 5129:130 4820:By 4719:on 4552:= t 4171:or 3531:of 3516:− λ 3508:of 3399:of 3085:If 3027:If 2994:of 2867:dim 2815:ker 2809:dim 2743:dim 2705:ker 2699:dim 2665:If 2564:If 2477:If 2211:of 2207:or 2016:If 1954:is 1897:If 1894:). 1851:in 1252:on 1025:in 1021:is 874:in 692:in 688:is 619:in 615:is 327:on 179:in 151:to 131:of 30:In 7340:: 6887:– 5368:. 5338:. 5324:. 5304:. 5294:. 5244:. 5217:. 5151:MR 5149:. 5141:. 5127:. 5121:. 5101:. 5091:. 5083:. 5008:^ 5001:64 4962:^ 4948:. 4924:^ 4886:^ 4545:Tx 4537:(t 4488:→ 4377:→ 4353:. 4183:Tr 3663:, 3575:. 3377:Id 2923:Id 2895:Im 2843:Id 2785:Id 2764:Im 2726:Id 2644:Id 2608:Id 2312:Id 2301:Im 2264:Id 2254:, 2215:. 1620:, 1372:. 1272:, 1230:Id 1221:. 482:. 312:. 7265:) 6989:) 6985:/ 6981:( 6891:) 6873:e 6866:t 6859:v 6800:( 6785:B 6783:( 6743:( 6611:( 6596:( 6560:( 6530:( 6280:) 6158:e 6151:t 6144:v 6050:) 6046:( 5947:) 5943:( 5506:e 5499:t 5492:v 5474:) 5468:( 5463:) 5459:( 5449:· 5442:· 5435:· 5428:· 5401:. 5376:. 5346:. 5312:. 5275:. 5252:. 5225:. 5195:. 5176:. 5157:. 5135:: 5109:. 5071:. 4956:. 4805:y 4801:d 4796:) 4793:y 4790:( 4787:f 4784:) 4781:y 4778:, 4775:x 4772:( 4769:k 4756:= 4753:) 4750:x 4747:( 4744:) 4741:f 4738:T 4735:( 4725:R 4721:L 4717:T 4709:R 4705:k 4701:R 4696:. 4690:T 4676:. 4673:t 4669:d 4664:) 4661:t 4658:( 4655:g 4652:) 4649:t 4646:( 4643:f 4638:x 4633:0 4625:= 4622:) 4619:x 4616:( 4613:) 4610:f 4607:T 4604:( 4594:R 4590:C 4586:R 4582:C 4578:T 4574:R 4570:C 4566:g 4558:n 4556:x 4554:n 4550:n 4547:) 4541:) 4539:n 4521:p 4490:Y 4486:X 4482:T 4474:X 4468:( 4466:Y 4452:) 4447:n 4443:x 4439:T 4436:( 4426:X 4412:) 4407:n 4403:x 4399:( 4379:Y 4375:X 4371:T 4367:Y 4363:X 4338:= 4334:| 4328:n 4319:| 4308:1 4305:= 4302:n 4271:n 4249:n 4246:1 4241:= 4236:n 4205:) 4201:| 4197:T 4193:| 4189:( 4163:. 4149:n 4145:g 4135:, 4130:n 4126:f 4117:n 4107:N 4102:1 4099:= 4096:n 4088:= 4085:T 4055:, 4052:2 4049:, 4046:1 4043:= 4040:k 4019:N 4012:N 3992:0 3989:= 3984:k 3981:+ 3978:N 3942:, 3937:2 3929:, 3924:1 3899:} 3893:, 3888:2 3884:g 3880:, 3875:1 3871:g 3867:{ 3847:} 3841:, 3836:2 3832:f 3828:, 3823:1 3819:f 3815:{ 3803:, 3789:n 3785:g 3775:, 3770:n 3766:f 3757:n 3742:1 3739:= 3736:n 3728:= 3725:T 3706:, 3692:H 3682:H 3674:T 3651:) 3642:, 3633:, 3628:H 3623:( 3600:T 3518:I 3514:K 3510:K 3498:C 3490:C 3486:K 3474:u 3470:f 3466:K 3450:f 3447:= 3444:u 3441:) 3438:I 3435:+ 3432:K 3426:( 3403:. 3401:X 3381:X 3367:T 3347:) 3344:T 3341:( 3311:} 3307:r 3300:| 3292:| 3288:: 3285:) 3282:T 3279:( 3266:{ 3262:= 3257:r 3253:E 3232:0 3226:r 3215:. 3197:T 3175:T 3134:) 3131:T 3128:( 3099:0 3082:. 3070:) 3067:T 3064:( 3055:0 3035:X 3003:T 2982:) 2979:T 2976:( 2946:) 2940:) 2928:X 2907:T 2902:( 2891:/ 2881:X 2875:( 2864:= 2860:) 2848:X 2827:T 2822:( 2806:= 2801:) 2795:) 2789:X 2775:T 2771:( 2760:/ 2756:X 2751:( 2740:= 2736:) 2730:X 2716:T 2712:( 2679:0 2648:X 2634:T 2612:X 2598:T 2578:0 2549:S 2543:T 2523:T 2517:S 2497:X 2491:X 2485:S 2462:N 2459:+ 2456:M 2435:N 2414:M 2393:X 2371:N 2349:M 2328:) 2325:T 2316:X 2307:( 2277:T 2268:X 2242:) 2239:X 2236:( 2233:K 2227:T 2213:T 2185:X 2172:X 2159:T 2138:X 2132:X 2126:T 2106:X 2081:X 2060:X 2054:X 2051:: 2048:T 2024:X 1996:T 1985:Y 1970:T 1958:. 1941:T 1917:Y 1911:X 1908:: 1905:T 1880:. 1868:) 1865:X 1862:( 1859:B 1835:) 1832:X 1829:( 1826:K 1802:, 1799:) 1796:Z 1793:, 1790:W 1787:( 1784:K 1778:) 1775:X 1772:, 1769:W 1766:( 1763:B 1757:) 1754:Y 1751:, 1748:X 1745:( 1742:K 1736:) 1733:Z 1730:, 1727:Y 1724:( 1721:B 1711:. 1709:Y 1705:X 1687:Y 1681:X 1661:Y 1658:, 1655:X 1629:T 1604:T 1581:N 1574:n 1570:) 1564:n 1560:T 1556:( 1536:Y 1533:, 1530:X 1510:Y 1504:X 1481:N 1474:n 1470:) 1464:n 1460:T 1456:( 1433:) 1430:Y 1427:, 1424:X 1421:( 1418:B 1398:) 1395:Y 1392:, 1389:X 1386:( 1383:K 1360:) 1357:X 1354:, 1351:X 1348:( 1345:K 1342:= 1339:) 1336:X 1333:( 1330:K 1310:) 1307:X 1304:, 1301:X 1298:( 1295:B 1292:= 1289:) 1286:X 1283:( 1280:B 1260:X 1234:X 1209:Y 1203:X 1183:) 1180:Y 1177:, 1174:X 1171:( 1168:K 1144:Y 1138:X 1118:) 1115:Y 1112:, 1109:X 1106:( 1103:B 1083:W 1080:, 1077:Z 1074:, 1071:Y 1068:, 1065:X 1045:. 1033:Y 1008:T 986:X 960:Y 932:N 925:n 921:) 915:n 911:x 907:T 904:( 883:X 859:N 852:n 848:) 842:n 838:x 834:( 823:; 811:V 805:) 802:U 799:( 796:T 776:Y 770:V 749:X 728:U 714:; 701:Y 675:T 653:X 641:; 628:Y 602:T 580:X 555:T 531:Y 525:X 522:: 519:T 499:Y 496:, 493:X 469:Y 448:) 445:U 442:( 439:T 418:X 396:U 367:Y 361:X 358:: 355:T 325:K 275:Y 245:T 217:Y 214:, 211:X 187:Y 163:Y 139:X 115:T 91:Y 88:, 85:X 65:Y 59:X 56:: 53:T 20:)

Index

Approximation problem
functional analysis
mathematics
linear operator
normed vector spaces
bounded subsets
relatively compact
closure
bounded operator
Banach
rank
finite-rank operators
Hilbert space
norm topology
approximation property
Per Enflo
Grothendieck
Banach
integral equations
Fredholm integral equation
function spaces
equicontinuity
Fredholm operator
topological vector spaces
relatively compact
relatively compact
neighbourhood
totally bounded
operator norm
identity operator

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