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Banach algebra

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Proof: Since every element of a commutative C*-algebra is normal, the Gelfand representation is isometric; in particular, it is injective and its image is closed. But the image of the Gelfand representation is dense by the
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is a real Banach algebra, but it is not a complex algebra (and hence not a complex Banach algebra) for the simple reason that the center of the quaternions is the real numbers, which cannot contain a copy of the complex
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since the kernel of a character is a maximal ideal, which is closed. Moreover, the norm (that is, operator norm) of a character is one. Equipped with the topology of pointwise convergence on
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is isomorphic to the reals, the complexes, or the quaternions. Hence, the only complex Banach algebra that is a division algebra is the complexes. (This is known as the
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The various algebras of functions given in the examples above have very different properties from standard examples of algebras such as the reals. For example:
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is zero) if and only if its Gelfand representation has trivial kernel. An important example of such an algebra is a commutative C*-algebra. In fact, when
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is a Banach algebra that is a field, and it follows from the Gelfand–Mazur theorem that there is a bijection between the set of all maximal ideals of
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of an element of a nontrivial complex Banach algebra can never be empty, whereas in a real Banach algebra it could be empty for some elements.
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and then applying the outcome in the original algebra. However, this is not the case all the time. For example, one cannot define all the
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The algebra of all bounded real- or complex-valued functions defined on some set (with pointwise multiplication and the
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The theory of real Banach algebras can be very different from the theory of complex Banach algebras. For example, the
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is a certain kind of Banach algebra over a nonarchimedean field. Affinoid algebras are the basic building blocks in
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of a C*-algebra coincides with its spectral radius. This generalizes an analogous fact for normal operators.
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Every commutative real unital Noetherian Banach algebra (possibly having zero divisors) is finite-dimensional.
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is a commutative unital C*-algebra, the Gelfand representation is then an isometric *-isomorphism between
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form a 4-dimensional real Banach algebra, with the norm being given by the absolute value of quaternions.
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that the algebra under consideration is unital because one can develop much of the theory by considering
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Unital Banach algebras over the complex field provide a general setting to develop spectral theory. The
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Some authors include this isometric property in the definition of a Banach *-algebra.
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with the supremum norm and that contains the constants and separates the points of
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Banach algebra with no zero divisors is isomorphic to the real or complex numbers.
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The set of real (or complex) numbers is a Banach algebra with norm given by the
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is then a commutative ring with unit, every non-invertible element of
583:. More generally, every C*-algebra is a Banach algebra by definition. 4933: 4931: 4055:{\displaystyle \sigma ({\hat {x}})=\{\chi (x):\chi \in \Delta (A)\}.} 4979: 1830:
have a multiplicative inverse element in a Banach algebra extension
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be a complex unital Banach algebra in which every non-zero element
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may be defined in any unital Banach algebra; examples include the
5130:. Chicago Lectures in Mathematics. University of Chicago Press). 5101:
Introduction to Banach Algebras, Operators and Harmonic Analysis
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in the formula above, is the spectrum as element of the algebra
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is a Banach algebra and closed ideal. It is without identity if
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In most natural examples, one also has that the involution is
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In other words, a Banach *-algebra is a Banach algebra over
1498:. (In particular, the exponential map can be used to define 1261:{\displaystyle xy(g)=\int x(h)y\left(h^{-1}g\right)d\mu (h)} 4964:"A New Simple Proof of the Gelfand-Mazur-Kaplansky Theorem" 1510:
also holds for two commuting elements of a Banach algebra.
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GarcĂ­a, Miguel Cabrera; Palacios, Angel RodrĂ­guez (1995).
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Banach algebra if we equip it with a sub-multiplicative
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Pages displaying short descriptions of redirect targets
976:(with functional composition as multiplication and the 4460:{\displaystyle (\lambda x)^{*}={\bar {\lambda }}x^{*}} 4064:
As an algebra, a unital commutative Banach algebra is
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of bounded linear operators on a complex Banach space
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of complex continuous functions on the compact space
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some elements that are singular in the given algebra
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Permanently singular elements in Banach algebras are
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remains valid in general unital Banach algebras. The
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induced by the norm. The norm is required to satisfy
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Dales, H. G.; Aeina, P.; Eschmeier, J; Laursen, K.;
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Pages displaying wikidata descriptions as a fallback
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as norm) is a unital Banach algebra. The set of all
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Graduate Texts in Mathematics. Vol. 96. 2804:is invertible (a division algebra). For every 7674:{\displaystyle S\left(\mathbb {R} ^{n}\right)} 3681:{\displaystyle \sigma (x)=\sigma ({\hat {x}})} 248:(whether it is unital or not) can be embedded 7782:Mathematical formulation of quantum mechanics 6327: 5843: 5191: 8: 4828: 4822: 4819: 4806: 4800: 4784: 4743: 4737: 4731: 4718: 4046: 4010: 2723: 2696: 2517:{\displaystyle \sigma (f(x))=f(\sigma (x)).} 2304: 2290: 2268: 2231: 2124: 2118: 719: 713: 143: 137: 133: 127: 118: 108: 3870:{\displaystyle {\hat {x}}(\chi )=\chi (x).} 3436:{\displaystyle \chi (ab)=\chi (a)\chi (b),} 2892:is not invertible (because the spectrum of 2732:{\displaystyle \sigma (f)=\{f(t):t\in X\}.} 6334: 6320: 6312: 5878: 5850: 5836: 5828: 5198: 5184: 5176: 1373:(which must be a compact Hausdorff space). 942:real- or complex-valued functions on some 7738: 7720: 7661: 7657: 7656: 7646: 7614: 7608: 7575: 7569: 7523: 7517: 7457:{\displaystyle B_{p,q}^{s}(\mathbb {R} )} 7447: 7446: 7437: 7426: 7420: 7371: 4834:{\displaystyle \|x^{*}x\|=\|x^{*}\|\|x\|} 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2000: 1968: 1939: 1898: 1878: 1858: 1835: 1815: 1795: 1775: 1741:Every unital real Banach algebra with no 1709: 1682: 1659: 1624: 1604: 1584: 1560: 1558: 1535: 1533: 1443: 1442: 1440: 1384: 1358: 1329: 1291: 1273: 1226: 1179: 1156: 1136: 1106: 1100: 1076: 1046: 1009: 989: 961: 898: 888: 869: 859: 836: 817: 797: 778: 767: 762:and define multiplication componentwise: 747: 741: 732: 729: 711: 690: 686: 685: 682: 661: 657: 656: 653: 619: 599: 554: 548: 516: 486: 480: 456: 423: 417: 387: 364: 328: 322: 297: 291: 263: 257: 233: 202: 147: 136: 114: 106: 54: 6140:Group algebra of a locally compact group 5008: 4488:{\displaystyle \lambda \in \mathbb {C} } 4266:{\displaystyle \left(x^{*}\right)^{*}=x} 2854:{\displaystyle \lambda \in \mathbb {C} } 7547:{\displaystyle L^{\lambda ,p}(\Omega )} 4915: 4890: 2939:{\displaystyle a=\lambda \mathbf {1} :} 7787:Ordinary Differential Equations (ODEs) 6901:Banach–Steinhaus (Uniform boundedness) 4949: 4937: 4922: 4180:is a Banach algebra over the field of 3473:{\displaystyle \chi (\mathbf {1} )=1.} 2885:{\displaystyle a-\lambda \mathbf {1} } 2039:{\displaystyle x-\lambda \mathbf {1} } 1612:{\displaystyle xy-yx\neq \mathbf {1} } 348:in a Banach algebra without identity. 27:Particular kind of algebraic structure 5518:Spectral theory of normal C*-algebras 5316:Spectral theory of normal C*-algebras 4875: â€“ Branch of functional analysis 4363:{\displaystyle (x+y)^{*}=x^{*}+y^{*}} 1417:: A Banach algebra consisting of all 755:{\displaystyle \|x\|=\max _{}|x_{i}|} 197:for the multiplication whose norm is 186:with respect to the metric topology. 7: 5513:Spectral theory of compact operators 1730:Every real Banach algebra that is a 4633:{\displaystyle (xy)^{*}=y^{*}x^{*}} 4222:that has the following properties: 3173: 3121: 1517:in any unital Banach algebra is an 1171:becomes a Banach algebra under the 7615: 7576: 7538: 7382: 5665:Cohen–Hewitt factorization theorem 4125: 4034: 3954: 3922: 3777: 3579: 3289: 3237:of all nonzero homomorphisms from 3215: 2285: 1770:, that is, considering extensions 1023: 85:) that at the same time is also a 25: 7279:Subsets / set operations 7056:Differentiation in FrĂ©chet spaces 5670:Extensions of symmetric operators 4546:{\displaystyle {\bar {\lambda }}} 3181:{\displaystyle A/{\mathfrak {m}}} 935:norm) is a unital Banach algebra. 7823:Science and technology in Poland 6296: 6295: 6222:Topological quantum field theory 5488:Positive operator-valued measure 3770:is the continuous function from 3457: 2929: 2878: 2654:(with a compact Hausdorff space 2615:coincides with the usual one in 2032: 1992:, consists of all those complex 1853:Topological divisors of zero in 1605: 1561: 1536: 1312:{\displaystyle x,y\in L^{1}(G).} 699:{\displaystyle \mathbb {C} ^{n}} 670:{\displaystyle \mathbb {R} ^{n}} 7584:{\displaystyle \ell ^{\infty }} 5772:Rayleigh–Faber–Krahn inequality 5074:A Course in Functional Analysis 4746: 3129:{\displaystyle {\mathfrak {m}}} 2367:holomorphic functional calculus 1377:Natural Banach function algebra 1032:{\displaystyle \dim E=\infty .} 594:The set of all real or complex 450:locally compact Hausdorff space 146: 7744: 7725: 7541: 7535: 7451: 7443: 7385: 7379: 6973:Lomonosov's invariant subspace 6896:Banach–Schauder (open mapping) 5103:. Cambridge University Press. 5032:. Cambridge University Press. 4777:A Banach *-algebra satisfying 4598: 4588: 4537: 4441: 4423: 4413: 4325: 4312: 4206: 4146:{\displaystyle C(\Delta (A)).} 4137: 4134: 4128: 4122: 4043: 4037: 4022: 4016: 4004: 3998: 3989: 3963: 3957: 3934: 3931: 3925: 3919: 3890: 3861: 3855: 3846: 3840: 3834: 3786: 3780: 3754: 3701: 3675: 3669: 3660: 3651: 3645: 3604:is a Hausdorff compact space. 3588: 3582: 3461: 3453: 3427: 3421: 3415: 3409: 3400: 3391: 3338:and its members "characters". 3298: 3292: 3224: 3218: 2708: 2702: 2690: 2684: 2641: 2635: 2562: 2556: 2508: 2505: 2499: 2493: 2484: 2481: 2475: 2469: 2443: 2437: 2385: 2379: 2282: 2265: 2259: 2243: 2235: 2180: 2174: 1979: 1973: 1756:Every commutative real unital 1340: 1334: 1303: 1297: 1255: 1249: 1211: 1205: 1193: 1187: 1118: 1112: 748: 733: 566: 560: 498: 492: 435: 429: 1: 6018:Uniform boundedness principle 5680:Limiting absorption principle 5150:Theory of Operator Algebras I 5054:. New York: Springer-Verlag. 4215:{\displaystyle {}^{*}:A\to A} 3940:{\displaystyle C(\Delta (A))} 3518:{\displaystyle \mathbb {C} ,} 3275:{\displaystyle \mathbb {C} .} 3038:{\displaystyle \mathbb {C} .} 2741:The norm of a normal element 1546:{\displaystyle \mathbf {1} ,} 1528:If a Banach algebra has unit 252:into a unital Banach algebra 6858:Singular value decomposition 5306:Singular value decomposition 4693:{\displaystyle \mathbb {C} } 3814:{\displaystyle \mathbb {C} } 2981:{\displaystyle \mathbb {C} } 2104:{\displaystyle \mathbb {C} } 2069:The spectrum of any element 1768:topological divisors of zero 1568:{\displaystyle \mathbf {1} } 1450:{\displaystyle \mathbb {H} } 956:operators on a Banach space 7623:{\displaystyle L^{\infty }} 7391:{\displaystyle ba(\Sigma )} 7260:Radially convex/Star-shaped 5737:Hearing the shape of a drum 5420:Decomposition of a spectrum 3972:{\displaystyle \Delta (A).} 3902:{\displaystyle {\hat {x}},} 3597:{\displaystyle \Delta (A),} 2966:is naturally isomorphic to 2452:{\displaystyle \sigma (x).} 938:The algebra of all bounded 189:A Banach algebra is called 7839: 7750:{\displaystyle W(X,L^{p})} 6161:Invariant subspace problem 5325:Special Elements/Operators 3792:{\displaystyle \Delta (A)} 3763:{\displaystyle {\hat {x}}} 3710:{\displaystyle {\hat {x}}} 3361:is a linear functional on 3315:" or "character space" of 3304:{\displaystyle \Delta (A)} 3230:{\displaystyle \Delta (A)} 2186:{\displaystyle \sigma (x)} 1985:{\displaystyle \sigma (x)} 1923: 7296:Algebraic interior (core) 6911:Cauchy–Schwarz inequality 6554:Function space Topologies 6291: 5881: 5797:Superstrong approximation 5660:Banach algebra cohomology 5493:Projection-valued measure 5478:Borel functional calculus 5250:Projection-valued measure 4900:Stone–Weierstrass theorem 4668:{\displaystyle x,y\in A.} 4573:{\displaystyle \lambda .} 4398:{\displaystyle x,y\in A.} 2647:{\displaystyle f\in C(X)} 2397:{\displaystyle f(x)\in A} 2164:. Moreover, the spectrum 1647:{\displaystyle x,y\in A.} 1494:, and more generally any 1151:-integrable functions on 511:is unital if and only if 224:if its multiplication is 6130:Spectrum of a C*-algebra 5389:Spectrum of a C*-algebra 5260:Spectrum of a C*-algebra 5109:10.1017/CBO9780511615429 5052:Complete Normed Algebras 3572:), the character space, 2526:When the Banach algebra 2008:{\displaystyle \lambda } 1124:{\displaystyle L^{1}(G)} 1095:, then the Banach space 572:{\displaystyle C_{0}(X)} 504:{\displaystyle C_{0}(X)} 441:{\displaystyle C_{0}(X)} 6227:Noncommutative geometry 5817:Wiener–Khinchin theorem 5752:Kuznetsov trace formula 5727:Almost Mathieu operator 5545:Banach function algebra 5534:Amenable Banach algebra 5291:Gelfand–Naimark theorem 5245:Noncommutative topology 4517:{\displaystyle x\in A;} 3629:{\displaystyle x\in A,} 2826:{\displaystyle a\in A,} 2358:{\displaystyle x\in A,} 1956:{\displaystyle x\in A,} 1502:.) The formula for the 1492:trigonometric functions 1467:rigid analytic geometry 1427:convolution of measures 346:trigonometric functions 7751: 7675: 7624: 7585: 7548: 7458: 7392: 6561:Banach–Mazur compactum 6351:Types of Banach spaces 6283:Tomita–Takesaki theory 6258:Approximation property 6202:Calculus of variations 5792:Sturm–Liouville theory 5690:Sherman–Takeda theorem 5570:Tomita–Takesaki theory 5345:Hermitian/Self-adjoint 5296:Gelfand representation 4864:Kaplansky's conjecture 4835: 4768: 4694: 4669: 4634: 4574: 4547: 4518: 4489: 4461: 4399: 4364: 4293: 4292:{\displaystyle x\in A} 4267: 4216: 4184:, together with a map 4174: 4147: 4106: 4086: 4056: 3973: 3941: 3903: 3871: 3815: 3793: 3764: 3735: 3719:Gelfand representation 3711: 3682: 3630: 3598: 3566: 3539: 3519: 3494: 3474: 3437: 3375: 3355: 3332: 3305: 3276: 3251: 3231: 3202: 3182: 3150: 3130: 3112:Since a maximal ideal 3106: 3079: 3059: 3039: 3010: 2982: 2960: 2940: 2906: 2886: 2855: 2827: 2798: 2778: 2755: 2733: 2668: 2648: 2609: 2589: 2569: 2540: 2518: 2453: 2418: 2398: 2359: 2328: 2207: 2187: 2154: 2131: 2105: 2083: 2063: 2040: 2009: 1986: 1957: 1910: 1887: 1867: 1847: 1824: 1804: 1784: 1718: 1694: 1671: 1648: 1613: 1569: 1547: 1525:under multiplication. 1451: 1396: 1367: 1347: 1313: 1262: 1165: 1145: 1125: 1085: 1055: 1033: 998: 970: 916: 756: 700: 671: 648:Take the Banach space 628: 608: 573: 525: 505: 465: 442: 396: 373: 338: 307: 273: 242: 214: 174: 63: 7777:Finite element method 7772:Differential operator 7752: 7676: 7625: 7586: 7549: 7459: 7393: 7233:Convex series related 7029:Abstract Wiener space 6956:hyperplane separation 6511:Minkowski functionals 6395:Polarization identity 6278:Banach–Mazur distance 6241:Generalized functions 5286:Gelfand–Mazur theorem 5126:Mosak, R. D. (1975). 5050:; Duncan, J. (1973). 4836: 4769: 4695: 4670: 4635: 4575: 4548: 4519: 4490: 4462: 4400: 4365: 4294: 4268: 4217: 4175: 4148: 4107: 4087: 4057: 3974: 3942: 3904: 3872: 3816: 3794: 3765: 3736: 3712: 3683: 3631: 3599: 3567: 3565:{\displaystyle A^{*}} 3540: 3520: 3495: 3475: 3438: 3376: 3356: 3354:{\displaystyle \chi } 3333: 3306: 3277: 3252: 3232: 3203: 3183: 3151: 3131: 3107: 3080: 3060: 3040: 3011: 2992:Ideals and characters 2983: 2961: 2941: 2907: 2887: 2856: 2828: 2799: 2779: 2756: 2734: 2669: 2649: 2610: 2590: 2570: 2541: 2519: 2454: 2427:in a neighborhood of 2419: 2399: 2360: 2329: 2208: 2188: 2155: 2132: 2130:{\displaystyle \|x\|} 2106: 2084: 2064: 2046:is not invertible in 2041: 2010: 1987: 1958: 1911: 1888: 1868: 1848: 1825: 1805: 1785: 1745:, and in which every 1736:Gelfand–Mazur theorem 1719: 1695: 1672: 1649: 1614: 1570: 1548: 1500:abstract index groups 1482:that are defined via 1452: 1423:locally compact group 1397: 1368: 1348: 1314: 1263: 1166: 1146: 1126: 1086: 1056: 1034: 999: 971: 944:locally compact space 917: 757: 701: 672: 629: 609: 574: 526: 506: 466: 443: 397: 374: 339: 337:{\displaystyle A_{e}} 308: 306:{\displaystyle A_{e}} 274: 272:{\displaystyle A_{e}} 243: 228:. Any Banach algebra 215: 175: 64: 7719: 7645: 7607: 7568: 7516: 7419: 7370: 7359:Absolute continuity 7013:Schauder fixed-point 7003:Riesz representation 6963:Kakutani fixed-point 6931:Freudenthal spectral 6417:L-semi-inner product 6023:Kakutani fixed-point 6008:Riesz representation 5762:Proto-value function 5741:Dirichlet eigenvalue 5655:Abstract index group 5540:Approximate identity 5503:Rigged Hilbert space 5379:Krein–Rutman theorem 5225:Involution/*-algebra 4855:Approximate identity 4781: 4715: 4682: 4644: 4585: 4561: 4528: 4499: 4471: 4410: 4374: 4309: 4277: 4229: 4188: 4164: 4116: 4096: 4076: 3983: 3951: 3913: 3881: 3825: 3803: 3774: 3745: 3741:defined as follows: 3725: 3692: 3639: 3611: 3576: 3549: 3529: 3504: 3484: 3447: 3385: 3365: 3345: 3319: 3286: 3261: 3241: 3212: 3192: 3160: 3140: 3116: 3093: 3069: 3049: 3024: 3020:Banach algebra over 3000: 2970: 2950: 2916: 2912:is not empty) hence 2896: 2865: 2837: 2808: 2788: 2768: 2745: 2678: 2658: 2623: 2599: 2579: 2568:{\displaystyle L(X)} 2550: 2530: 2463: 2431: 2408: 2373: 2340: 2225: 2197: 2168: 2141: 2115: 2093: 2073: 2050: 2019: 1999: 1967: 1938: 1897: 1877: 1857: 1834: 1814: 1794: 1774: 1708: 1681: 1658: 1623: 1583: 1557: 1532: 1488:exponential function 1480:elementary functions 1439: 1383: 1357: 1346:{\displaystyle C(X)} 1328: 1272: 1178: 1155: 1144:{\displaystyle \mu } 1135: 1099: 1084:{\displaystyle \mu } 1075: 1045: 1008: 988: 960: 766: 710: 681: 652: 618: 598: 547: 515: 479: 455: 416: 386: 363: 321: 313:. Often one assumes 290: 256: 232: 201: 105: 53: 7442: 7180:measurable function 7130:Functional calculus 6993:Parseval's identity 6906:Bessel's inequality 6853:Polar decomposition 6632:Uniform convergence 6390:Inner product space 6207:Functional calculus 6166:Mahler's conjecture 6145:Von Neumann algebra 5859:Functional analysis 5565:Von Neumann algebra 5301:Polar decomposition 4749: for all  4160:A Banach *-algebra 1790:of Banach algebras 1515:invertible elements 1432:The algebra of the 949:The algebra of all 537:complex conjugation 149: for all  77:numbers (or over a 48:associative algebra 36:functional analysis 7792:Validated numerics 7747: 7703:Sobolev inequality 7671: 7620: 7581: 7544: 7473:Bounded variation 7454: 7422: 7407:Banach coordinate 7388: 7326:Minkowski addition 6988:M. Riesz extension 6468:Banach spaces are: 6232:Riemann hypothesis 5931:Topological vector 5695:Unbounded operator 5624:Essential spectrum 5603:Schur–Horn theorem 5593:Bauer–Fike theorem 5588:Alon–Boppana bound 5581:Finite-Dimensional 5555:Nuclear C*-algebra 5399:Spectral asymmetry 5011:, Proposition 2.8. 4952:, Theorem VII.2.2. 4940:, Example VII.1.9. 4925:, Example VII.1.8. 4831: 4764: 4690: 4665: 4630: 4570: 4543: 4514: 4485: 4457: 4395: 4360: 4299:(so the map is an 4289: 4263: 4212: 4170: 4143: 4102: 4082: 4052: 3969: 3937: 3899: 3867: 3811: 3789: 3760: 3731: 3707: 3678: 3626: 3594: 3562: 3535: 3515: 3490: 3470: 3433: 3371: 3351: 3331:{\displaystyle A,} 3328: 3301: 3272: 3247: 3227: 3198: 3178: 3146: 3126: 3105:{\displaystyle A.} 3102: 3075: 3055: 3035: 3006: 2978: 2956: 2936: 2902: 2882: 2851: 2823: 2794: 2774: 2751: 2729: 2674:), one sees that: 2664: 2644: 2605: 2585: 2565: 2536: 2514: 2449: 2414: 2394: 2355: 2324: 2289: 2217:and satisfies the 2203: 2183: 2153:{\displaystyle 0,} 2150: 2127: 2101: 2079: 2062:{\displaystyle A.} 2059: 2036: 2005: 1982: 1953: 1909:{\displaystyle A.} 1906: 1883: 1863: 1846:{\displaystyle B.} 1843: 1820: 1800: 1780: 1717:{\displaystyle 0.} 1714: 1693:{\displaystyle yx} 1690: 1670:{\displaystyle xy} 1667: 1644: 1609: 1565: 1543: 1447: 1395:{\displaystyle X.} 1392: 1363: 1343: 1309: 1258: 1161: 1141: 1121: 1081: 1051: 1029: 994: 966: 912: 752: 731: 696: 667: 624: 604: 569: 521: 501: 473:vanish at infinity 461: 438: 392: 381:. This is part of 369: 334: 303: 269: 238: 213:{\displaystyle 1,} 210: 170: 59: 7800: 7799: 7512:Morrey–Campanato 7494:compact Hausdorff 7341:Relative interior 7195:Absolutely convex 7162:Projection-valued 6771:Strictly singular 6697:on Hilbert spaces 6458:of Hilbert spaces 6309: 6308: 6212:Integral operator 5989: 5988: 5825: 5824: 5802:Transfer operator 5777:Spectral geometry 5462:Spectral abscissa 5442:Approximate point 5384:Normal eigenvalue 5159:978-3-540-42248-8 4750: 4555:complex conjugate 4540: 4444: 4173:{\displaystyle A} 4156:Banach *-algebras 4105:{\displaystyle A} 4085:{\displaystyle A} 4001: 3893: 3837: 3757: 3734:{\displaystyle x} 3704: 3672: 3538:{\displaystyle A} 3493:{\displaystyle A} 3374:{\displaystyle A} 3250:{\displaystyle A} 3201:{\displaystyle A} 3149:{\displaystyle A} 3078:{\displaystyle A} 3058:{\displaystyle A} 3009:{\displaystyle A} 2959:{\displaystyle A} 2905:{\displaystyle a} 2797:{\displaystyle x} 2777:{\displaystyle A} 2754:{\displaystyle x} 2667:{\displaystyle X} 2608:{\displaystyle A} 2588:{\displaystyle X} 2539:{\displaystyle A} 2417:{\displaystyle f} 2404:for any function 2369:allows to define 2274: 2206:{\displaystyle x} 2082:{\displaystyle x} 1886:{\displaystyle B} 1866:{\displaystyle A} 1823:{\displaystyle A} 1803:{\displaystyle A} 1783:{\displaystyle B} 1523:topological group 1366:{\displaystyle X} 1164:{\displaystyle G} 1069:topological group 1054:{\displaystyle G} 997:{\displaystyle E} 982:compact operators 969:{\displaystyle E} 725: 627:{\displaystyle n} 607:{\displaystyle n} 524:{\displaystyle X} 464:{\displaystyle X} 395:{\displaystyle p} 372:{\displaystyle p} 241:{\displaystyle A} 150: 123: 62:{\displaystyle A} 16:(Redirected from 7830: 7818:Fourier analysis 7756: 7754: 7753: 7748: 7743: 7742: 7710:Triebel–Lizorkin 7680: 7678: 7677: 7672: 7670: 7666: 7665: 7660: 7629: 7627: 7626: 7621: 7619: 7618: 7590: 7588: 7587: 7582: 7580: 7579: 7553: 7551: 7550: 7545: 7534: 7533: 7463: 7461: 7460: 7455: 7450: 7441: 7436: 7397: 7395: 7394: 7389: 7250: 7228: 7210:Balanced/Circled 7008:Robinson-Ursescu 6926:Eberlein–Šmulian 6846:Spectral theorem 6642:Linear operators 6439:Uniformly smooth 6336: 6329: 6322: 6313: 6299: 6298: 6217:Jones polynomial 6135:Operator algebra 5879: 5852: 5845: 5838: 5829: 5807:Transform theory 5527:Special algebras 5508:Spectral theorem 5471:Spectral Theorem 5311:Spectral theorem 5200: 5193: 5186: 5177: 5171: 5141: 5122: 5091: 5065: 5043: 5031: 5012: 5006: 5000: 4999: 4974:(9): 2663–2666. 4959: 4953: 4947: 4941: 4935: 4926: 4920: 4903: 4895: 4873:Operator algebra 4869: 4860: 4840: 4838: 4837: 4832: 4818: 4817: 4796: 4795: 4773: 4771: 4770: 4765: 4751: 4748: 4730: 4729: 4699: 4697: 4696: 4691: 4689: 4674: 4672: 4671: 4666: 4639: 4637: 4636: 4631: 4629: 4628: 4619: 4618: 4606: 4605: 4579: 4577: 4576: 4571: 4552: 4550: 4549: 4544: 4542: 4541: 4533: 4523: 4521: 4520: 4515: 4494: 4492: 4491: 4486: 4484: 4466: 4464: 4463: 4458: 4456: 4455: 4446: 4445: 4437: 4431: 4430: 4404: 4402: 4401: 4396: 4369: 4367: 4366: 4361: 4359: 4358: 4346: 4345: 4333: 4332: 4298: 4296: 4295: 4290: 4272: 4270: 4269: 4264: 4256: 4255: 4250: 4246: 4245: 4221: 4219: 4218: 4213: 4199: 4198: 4193: 4179: 4177: 4176: 4171: 4152: 4150: 4149: 4144: 4111: 4109: 4108: 4103: 4091: 4089: 4088: 4083: 4070:Jacobson radical 4061: 4059: 4058: 4053: 4003: 4002: 3994: 3978: 3976: 3975: 3970: 3946: 3944: 3943: 3938: 3908: 3906: 3905: 3900: 3895: 3894: 3886: 3877:The spectrum of 3876: 3874: 3873: 3868: 3839: 3838: 3830: 3820: 3818: 3817: 3812: 3810: 3798: 3796: 3795: 3790: 3769: 3767: 3766: 3761: 3759: 3758: 3750: 3740: 3738: 3737: 3732: 3716: 3714: 3713: 3708: 3706: 3705: 3697: 3687: 3685: 3684: 3679: 3674: 3673: 3665: 3635: 3633: 3632: 3627: 3603: 3601: 3600: 3595: 3571: 3569: 3568: 3563: 3561: 3560: 3544: 3542: 3541: 3536: 3524: 3522: 3521: 3516: 3511: 3499: 3497: 3496: 3491: 3479: 3477: 3476: 3471: 3460: 3442: 3440: 3439: 3434: 3380: 3378: 3377: 3372: 3360: 3358: 3357: 3352: 3337: 3335: 3334: 3329: 3310: 3308: 3307: 3302: 3281: 3279: 3278: 3273: 3268: 3256: 3254: 3253: 3248: 3236: 3234: 3233: 3228: 3207: 3205: 3204: 3199: 3187: 3185: 3184: 3179: 3177: 3176: 3170: 3155: 3153: 3152: 3147: 3135: 3133: 3132: 3127: 3125: 3124: 3111: 3109: 3108: 3103: 3085:belongs to some 3084: 3082: 3081: 3076: 3064: 3062: 3061: 3056: 3044: 3042: 3041: 3036: 3031: 3015: 3013: 3012: 3007: 2987: 2985: 2984: 2979: 2977: 2965: 2963: 2962: 2957: 2945: 2943: 2942: 2937: 2932: 2911: 2909: 2908: 2903: 2891: 2889: 2888: 2883: 2881: 2860: 2858: 2857: 2852: 2850: 2832: 2830: 2829: 2824: 2803: 2801: 2800: 2795: 2783: 2781: 2780: 2775: 2760: 2758: 2757: 2752: 2738: 2736: 2735: 2730: 2673: 2671: 2670: 2665: 2653: 2651: 2650: 2645: 2614: 2612: 2611: 2606: 2594: 2592: 2591: 2586: 2574: 2572: 2571: 2566: 2545: 2543: 2542: 2537: 2523: 2521: 2520: 2515: 2458: 2456: 2455: 2450: 2423: 2421: 2420: 2415: 2403: 2401: 2400: 2395: 2364: 2362: 2361: 2356: 2333: 2331: 2330: 2325: 2320: 2319: 2315: 2302: 2301: 2288: 2246: 2238: 2212: 2210: 2209: 2204: 2192: 2190: 2189: 2184: 2159: 2157: 2156: 2151: 2136: 2134: 2133: 2128: 2110: 2108: 2107: 2102: 2100: 2088: 2086: 2085: 2080: 2068: 2066: 2065: 2060: 2045: 2043: 2042: 2037: 2035: 2014: 2012: 2011: 2006: 1991: 1989: 1988: 1983: 1962: 1960: 1959: 1954: 1915: 1913: 1912: 1907: 1892: 1890: 1889: 1884: 1872: 1870: 1869: 1864: 1852: 1850: 1849: 1844: 1829: 1827: 1826: 1821: 1809: 1807: 1806: 1801: 1789: 1787: 1786: 1781: 1732:division algebra 1723: 1721: 1720: 1715: 1704:except possibly 1699: 1697: 1696: 1691: 1676: 1674: 1673: 1668: 1654:This is because 1653: 1651: 1650: 1645: 1619:  for any 1618: 1616: 1615: 1610: 1608: 1574: 1572: 1571: 1566: 1564: 1552: 1550: 1549: 1544: 1539: 1508:binomial theorem 1504:geometric series 1463:affinoid algebra 1456: 1454: 1453: 1448: 1446: 1401: 1399: 1398: 1393: 1372: 1370: 1369: 1364: 1352: 1350: 1349: 1344: 1318: 1316: 1315: 1310: 1296: 1295: 1267: 1265: 1264: 1259: 1242: 1238: 1234: 1233: 1170: 1168: 1167: 1162: 1150: 1148: 1147: 1142: 1130: 1128: 1127: 1122: 1111: 1110: 1090: 1088: 1087: 1082: 1060: 1058: 1057: 1052: 1038: 1036: 1035: 1030: 1003: 1001: 1000: 995: 975: 973: 972: 967: 921: 919: 918: 913: 908: 904: 903: 902: 893: 892: 874: 873: 864: 863: 846: 842: 841: 840: 822: 821: 807: 803: 802: 801: 783: 782: 761: 759: 758: 753: 751: 746: 745: 736: 730: 705: 703: 702: 697: 695: 694: 689: 676: 674: 673: 668: 666: 665: 660: 633: 631: 630: 625: 613: 611: 610: 605: 578: 576: 575: 570: 559: 558: 530: 528: 527: 522: 510: 508: 507: 502: 491: 490: 470: 468: 467: 462: 447: 445: 444: 439: 428: 427: 401: 399: 398: 393: 378: 376: 375: 370: 343: 341: 340: 335: 333: 332: 312: 310: 309: 304: 302: 301: 279:so as to form a 278: 276: 275: 270: 268: 267: 247: 245: 244: 239: 219: 217: 216: 211: 195:identity element 179: 177: 176: 171: 151: 148: 121: 68: 66: 65: 60: 21: 7838: 7837: 7833: 7832: 7831: 7829: 7828: 7827: 7813:Banach algebras 7803: 7802: 7801: 7796: 7760: 7734: 7717: 7716: 7715:Wiener amalgam 7685:Segal–Bargmann 7655: 7651: 7643: 7642: 7610: 7605: 7604: 7571: 7566: 7565: 7519: 7514: 7513: 7468:Birnbaum–Orlicz 7417: 7416: 7368: 7367: 7345: 7301:Bounding points 7274: 7248: 7226: 7183: 7034:Banach manifold 7017: 6941:Gelfand–Naimark 6862: 6836:Spectral theory 6804:Banach algebras 6796:Operator theory 6790: 6751:Pseudo-monotone 6734:Hilbert–Schmidt 6714:Densely defined 6636: 6549: 6463: 6346: 6340: 6310: 6305: 6287: 6251:Advanced topics 6246: 6170: 6149: 6108: 6074:Hilbert–Schmidt 6047: 6038:Gelfand–Naimark 5985: 5935: 5870: 5856: 5826: 5821: 5782:Spectral method 5767:Ramanujan graph 5715: 5699: 5675:Fredholm theory 5643: 5638:Shilov boundary 5634:Structure space 5612:Generalizations 5607: 5598:Numerical range 5576: 5560:Uniform algebra 5522: 5498:Riesz projector 5483:Min-max theorem 5466: 5452:Direct integral 5408: 5394:Spectral radius 5365: 5320: 5274: 5265:Spectral radius 5213: 5207:Spectral theory 5204: 5174: 5160: 5144: 5138: 5128:Banach algebras 5125: 5119: 5094: 5088: 5078:Springer Verlag 5068: 5062: 5046: 5040: 5028:Linear Analysis 5020: 5016: 5015: 5007: 5003: 4980:10.2307/2160559 4961: 4960: 4956: 4948: 4944: 4936: 4929: 4921: 4917: 4912: 4907: 4906: 4896: 4892: 4887: 4879:Shilov boundary 4867: 4858: 4851: 4809: 4787: 4779: 4778: 4721: 4713: 4712: 4700:that is also a 4680: 4679: 4642: 4641: 4620: 4610: 4597: 4583: 4582: 4559: 4558: 4526: 4525: 4497: 4496: 4469: 4468: 4447: 4422: 4408: 4407: 4372: 4371: 4350: 4337: 4324: 4307: 4306: 4275: 4274: 4237: 4233: 4232: 4227: 4226: 4191: 4186: 4185: 4182:complex numbers 4162: 4161: 4158: 4114: 4113: 4094: 4093: 4074: 4073: 3981: 3980: 3949: 3948: 3911: 3910: 3879: 3878: 3823: 3822: 3801: 3800: 3772: 3771: 3743: 3742: 3723: 3722: 3690: 3689: 3637: 3636: 3609: 3608: 3574: 3573: 3552: 3547: 3546: 3527: 3526: 3502: 3501: 3482: 3481: 3445: 3444: 3383: 3382: 3363: 3362: 3343: 3342: 3317: 3316: 3313:structure space 3311:is called the " 3284: 3283: 3259: 3258: 3239: 3238: 3210: 3209: 3190: 3189: 3158: 3157: 3138: 3137: 3114: 3113: 3091: 3090: 3067: 3066: 3047: 3046: 3022: 3021: 2998: 2997: 2994: 2968: 2967: 2948: 2947: 2914: 2913: 2894: 2893: 2863: 2862: 2835: 2834: 2806: 2805: 2786: 2785: 2766: 2765: 2743: 2742: 2676: 2675: 2656: 2655: 2621: 2620: 2617:operator theory 2597: 2596: 2577: 2576: 2548: 2547: 2546:is the algebra 2528: 2527: 2461: 2460: 2429: 2428: 2406: 2405: 2371: 2370: 2338: 2337: 2303: 2293: 2223: 2222: 2219:spectral radius 2195: 2194: 2166: 2165: 2139: 2138: 2113: 2112: 2091: 2090: 2071: 2070: 2048: 2047: 2017: 2016: 1997: 1996: 1965: 1964: 1936: 1935: 1928: 1926:Spectral theory 1922: 1920:Spectral theory 1895: 1894: 1875: 1874: 1855: 1854: 1832: 1831: 1812: 1811: 1792: 1791: 1772: 1771: 1747:principal ideal 1706: 1705: 1679: 1678: 1656: 1655: 1621: 1620: 1581: 1580: 1555: 1554: 1530: 1529: 1496:entire function 1476: 1437: 1436: 1415:Measure algebra 1381: 1380: 1355: 1354: 1326: 1325: 1322:Uniform algebra 1287: 1270: 1269: 1222: 1221: 1217: 1176: 1175: 1153: 1152: 1133: 1132: 1102: 1097: 1096: 1073: 1072: 1063:locally compact 1043: 1042: 1006: 1005: 986: 985: 958: 957: 894: 884: 865: 855: 854: 850: 832: 813: 812: 808: 793: 774: 773: 769: 764: 763: 737: 708: 707: 684: 679: 678: 655: 650: 649: 616: 615: 596: 595: 550: 545: 544: 513: 512: 482: 477: 476: 453: 452: 419: 414: 413: 410: 384: 383: 361: 360: 324: 319: 318: 293: 288: 287: 259: 254: 253: 230: 229: 199: 198: 103: 102: 79:non-Archimedean 51: 50: 28: 23: 22: 18:Structure space 15: 12: 11: 5: 7836: 7834: 7826: 7825: 7820: 7815: 7805: 7804: 7798: 7797: 7795: 7794: 7789: 7784: 7779: 7774: 7768: 7766: 7762: 7761: 7759: 7758: 7746: 7741: 7737: 7733: 7730: 7727: 7724: 7712: 7707: 7706: 7705: 7695: 7693:Sequence space 7690: 7682: 7669: 7664: 7659: 7654: 7650: 7638: 7637: 7636: 7631: 7617: 7613: 7594: 7593: 7592: 7578: 7574: 7555: 7543: 7540: 7537: 7532: 7529: 7526: 7522: 7509: 7501: 7496: 7483: 7478: 7470: 7465: 7453: 7449: 7445: 7440: 7435: 7432: 7429: 7425: 7412: 7404: 7399: 7387: 7384: 7381: 7378: 7375: 7364: 7355: 7353: 7347: 7346: 7344: 7343: 7333: 7328: 7323: 7318: 7313: 7308: 7303: 7298: 7288: 7282: 7280: 7276: 7275: 7273: 7272: 7267: 7262: 7257: 7252: 7244: 7230: 7222: 7217: 7212: 7207: 7202: 7197: 7191: 7189: 7185: 7184: 7182: 7181: 7171: 7170: 7169: 7164: 7159: 7149: 7148: 7147: 7142: 7137: 7127: 7126: 7125: 7120: 7115: 7110: 7108:Gelfand–Pettis 7105: 7100: 7090: 7089: 7088: 7083: 7078: 7073: 7068: 7058: 7053: 7048: 7043: 7042: 7041: 7031: 7025: 7023: 7019: 7018: 7016: 7015: 7010: 7005: 7000: 6995: 6990: 6985: 6980: 6975: 6970: 6965: 6960: 6959: 6958: 6948: 6943: 6938: 6933: 6928: 6923: 6918: 6913: 6908: 6903: 6898: 6893: 6888: 6883: 6881:Banach–Alaoglu 6878: 6876:Anderson–Kadec 6872: 6870: 6864: 6863: 6861: 6860: 6855: 6850: 6849: 6848: 6843: 6833: 6832: 6831: 6826: 6816: 6814:Operator space 6811: 6806: 6800: 6798: 6792: 6791: 6789: 6788: 6783: 6778: 6773: 6768: 6763: 6758: 6753: 6748: 6747: 6746: 6736: 6731: 6730: 6729: 6724: 6716: 6711: 6701: 6700: 6699: 6689: 6684: 6674: 6673: 6672: 6667: 6662: 6652: 6646: 6644: 6638: 6637: 6635: 6634: 6629: 6624: 6623: 6622: 6617: 6607: 6606: 6605: 6600: 6590: 6585: 6580: 6579: 6578: 6568: 6563: 6557: 6555: 6551: 6550: 6548: 6547: 6542: 6537: 6536: 6535: 6525: 6520: 6515: 6514: 6513: 6502:Locally convex 6499: 6498: 6497: 6487: 6482: 6477: 6471: 6469: 6465: 6464: 6462: 6461: 6454:Tensor product 6447: 6441: 6436: 6430: 6425: 6419: 6414: 6409: 6399: 6398: 6397: 6392: 6382: 6377: 6375:Banach lattice 6372: 6371: 6370: 6360: 6354: 6352: 6348: 6347: 6341: 6339: 6338: 6331: 6324: 6316: 6307: 6306: 6304: 6303: 6292: 6289: 6288: 6286: 6285: 6280: 6275: 6270: 6268:Choquet theory 6265: 6260: 6254: 6252: 6248: 6247: 6245: 6244: 6234: 6229: 6224: 6219: 6214: 6209: 6204: 6199: 6194: 6189: 6184: 6178: 6176: 6172: 6171: 6169: 6168: 6163: 6157: 6155: 6151: 6150: 6148: 6147: 6142: 6137: 6132: 6127: 6122: 6120:Banach algebra 6116: 6114: 6110: 6109: 6107: 6106: 6101: 6096: 6091: 6086: 6081: 6076: 6071: 6066: 6061: 6055: 6053: 6049: 6048: 6046: 6045: 6043:Banach–Alaoglu 6040: 6035: 6030: 6025: 6020: 6015: 6010: 6005: 5999: 5997: 5991: 5990: 5987: 5986: 5984: 5983: 5978: 5973: 5971:Locally convex 5968: 5954: 5949: 5943: 5941: 5937: 5936: 5934: 5933: 5928: 5923: 5918: 5913: 5908: 5903: 5898: 5893: 5888: 5882: 5876: 5872: 5871: 5857: 5855: 5854: 5847: 5840: 5832: 5823: 5822: 5820: 5819: 5814: 5809: 5804: 5799: 5794: 5789: 5784: 5779: 5774: 5769: 5764: 5759: 5754: 5749: 5744: 5734: 5732:Corona theorem 5729: 5723: 5721: 5717: 5716: 5714: 5713: 5711:Wiener algebra 5707: 5705: 5701: 5700: 5698: 5697: 5692: 5687: 5682: 5677: 5672: 5667: 5662: 5657: 5651: 5649: 5645: 5644: 5642: 5641: 5631: 5629:Pseudospectrum 5626: 5621: 5619:Dirac spectrum 5615: 5613: 5609: 5608: 5606: 5605: 5600: 5595: 5590: 5584: 5582: 5578: 5577: 5575: 5574: 5573: 5572: 5562: 5557: 5552: 5547: 5542: 5536: 5530: 5528: 5524: 5523: 5521: 5520: 5515: 5510: 5505: 5500: 5495: 5490: 5485: 5480: 5474: 5472: 5468: 5467: 5465: 5464: 5459: 5454: 5449: 5444: 5439: 5438: 5437: 5432: 5427: 5416: 5414: 5410: 5409: 5407: 5406: 5401: 5396: 5391: 5386: 5381: 5375: 5373: 5367: 5366: 5364: 5363: 5358: 5350: 5342: 5334: 5328: 5326: 5322: 5321: 5319: 5318: 5313: 5308: 5303: 5298: 5293: 5288: 5282: 5280: 5276: 5275: 5273: 5272: 5270:Operator space 5267: 5262: 5257: 5252: 5247: 5242: 5237: 5232: 5230:Banach algebra 5227: 5221: 5219: 5218:Basic concepts 5215: 5214: 5205: 5203: 5202: 5195: 5188: 5180: 5173: 5172: 5158: 5142: 5136: 5123: 5117: 5092: 5086: 5066: 5060: 5048:Bonsall, F. F. 5044: 5038: 5017: 5014: 5013: 5001: 4954: 4942: 4927: 4914: 4913: 4911: 4908: 4905: 4904: 4889: 4888: 4886: 4883: 4882: 4881: 4876: 4870: 4861: 4850: 4847: 4830: 4827: 4824: 4821: 4816: 4812: 4808: 4805: 4802: 4799: 4794: 4790: 4786: 4763: 4760: 4757: 4754: 4745: 4742: 4739: 4736: 4733: 4728: 4724: 4720: 4688: 4676: 4675: 4664: 4661: 4658: 4655: 4652: 4649: 4627: 4623: 4617: 4613: 4609: 4604: 4600: 4596: 4593: 4590: 4580: 4569: 4566: 4539: 4536: 4513: 4510: 4507: 4504: 4483: 4479: 4476: 4454: 4450: 4443: 4440: 4434: 4429: 4425: 4421: 4418: 4415: 4405: 4394: 4391: 4388: 4385: 4382: 4379: 4357: 4353: 4349: 4344: 4340: 4336: 4331: 4327: 4323: 4320: 4317: 4314: 4304: 4288: 4285: 4282: 4262: 4259: 4254: 4249: 4244: 4240: 4236: 4211: 4208: 4205: 4202: 4197: 4169: 4157: 4154: 4142: 4139: 4136: 4133: 4130: 4127: 4124: 4121: 4101: 4081: 4068:(that is, its 4051: 4048: 4045: 4042: 4039: 4036: 4033: 4030: 4027: 4024: 4021: 4018: 4015: 4012: 4009: 4006: 4000: 3997: 3991: 3988: 3968: 3965: 3962: 3959: 3956: 3936: 3933: 3930: 3927: 3924: 3921: 3918: 3898: 3892: 3889: 3866: 3863: 3860: 3857: 3854: 3851: 3848: 3845: 3842: 3836: 3833: 3809: 3788: 3785: 3782: 3779: 3756: 3753: 3730: 3703: 3700: 3677: 3671: 3668: 3662: 3659: 3656: 3653: 3650: 3647: 3644: 3625: 3622: 3619: 3616: 3593: 3590: 3587: 3584: 3581: 3559: 3555: 3534: 3514: 3510: 3489: 3469: 3466: 3463: 3459: 3455: 3452: 3443:and satisfies 3432: 3429: 3426: 3423: 3420: 3417: 3414: 3411: 3408: 3405: 3402: 3399: 3396: 3393: 3390: 3370: 3350: 3327: 3324: 3300: 3297: 3294: 3291: 3271: 3267: 3246: 3226: 3223: 3220: 3217: 3197: 3175: 3169: 3165: 3145: 3123: 3101: 3098: 3074: 3054: 3034: 3030: 3005: 2993: 2990: 2976: 2955: 2935: 2931: 2927: 2924: 2921: 2901: 2880: 2876: 2873: 2870: 2849: 2845: 2842: 2822: 2819: 2816: 2813: 2793: 2773: 2750: 2728: 2725: 2722: 2719: 2716: 2713: 2710: 2707: 2704: 2701: 2698: 2695: 2692: 2689: 2686: 2683: 2663: 2643: 2640: 2637: 2634: 2631: 2628: 2604: 2584: 2564: 2561: 2558: 2555: 2535: 2513: 2510: 2507: 2504: 2501: 2498: 2495: 2492: 2489: 2486: 2483: 2480: 2477: 2474: 2471: 2468: 2448: 2445: 2442: 2439: 2436: 2413: 2393: 2390: 2387: 2384: 2381: 2378: 2354: 2351: 2348: 2345: 2323: 2318: 2314: 2310: 2306: 2300: 2296: 2292: 2287: 2284: 2281: 2277: 2273: 2270: 2267: 2264: 2261: 2258: 2255: 2252: 2249: 2245: 2241: 2237: 2233: 2230: 2202: 2193:of an element 2182: 2179: 2176: 2173: 2149: 2146: 2126: 2123: 2120: 2099: 2078: 2058: 2055: 2034: 2030: 2027: 2024: 2004: 1981: 1978: 1975: 1972: 1952: 1949: 1946: 1943: 1934:of an element 1924:Main article: 1921: 1918: 1917: 1916: 1905: 1902: 1882: 1862: 1842: 1839: 1819: 1799: 1779: 1764: 1761: 1754: 1739: 1713: 1700:have the same 1689: 1686: 1666: 1663: 1643: 1640: 1637: 1634: 1631: 1628: 1607: 1603: 1600: 1597: 1594: 1591: 1588: 1563: 1542: 1538: 1475: 1472: 1471: 1470: 1459: 1445: 1430: 1419:Radon measures 1412: 1402: 1391: 1388: 1374: 1362: 1342: 1339: 1336: 1333: 1319: 1308: 1305: 1302: 1299: 1294: 1290: 1286: 1283: 1280: 1277: 1257: 1254: 1251: 1248: 1245: 1241: 1237: 1232: 1229: 1225: 1220: 1216: 1213: 1210: 1207: 1204: 1201: 1198: 1195: 1192: 1189: 1186: 1183: 1160: 1140: 1120: 1117: 1114: 1109: 1105: 1080: 1050: 1039: 1028: 1025: 1022: 1019: 1016: 1013: 993: 965: 947: 936: 929: 922: 911: 907: 901: 897: 891: 887: 883: 880: 877: 872: 868: 862: 858: 853: 849: 845: 839: 835: 831: 828: 825: 820: 816: 811: 806: 800: 796: 792: 789: 786: 781: 777: 772: 750: 744: 740: 735: 728: 724: 721: 718: 715: 693: 688: 664: 659: 646: 623: 603: 592: 589:absolute value 568: 565: 562: 557: 553: 520: 500: 497: 494: 489: 485: 460: 437: 434: 431: 426: 422: 409: 406: 402:-adic analysis 391: 368: 331: 327: 300: 296: 266: 262: 237: 209: 206: 169: 166: 163: 160: 157: 154: 145: 142: 139: 135: 132: 129: 126: 120: 117: 113: 110: 58: 42:, named after 40:Banach algebra 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 7835: 7824: 7821: 7819: 7816: 7814: 7811: 7810: 7808: 7793: 7790: 7788: 7785: 7783: 7780: 7778: 7775: 7773: 7770: 7769: 7767: 7763: 7757: 7739: 7735: 7731: 7728: 7722: 7713: 7711: 7708: 7704: 7701: 7700: 7699: 7696: 7694: 7691: 7689: 7688: 7683: 7681: 7667: 7662: 7652: 7648: 7639: 7635: 7632: 7630: 7611: 7602: 7601: 7600: 7599: 7595: 7591: 7572: 7563: 7562: 7561: 7560: 7556: 7554: 7530: 7527: 7524: 7520: 7510: 7508: 7507: 7502: 7500: 7497: 7495: 7493: 7489: 7484: 7482: 7479: 7477: 7476: 7471: 7469: 7466: 7464: 7438: 7433: 7430: 7427: 7423: 7413: 7411: 7410: 7405: 7403: 7400: 7398: 7376: 7373: 7365: 7363: 7362: 7357: 7356: 7354: 7352: 7348: 7342: 7338: 7334: 7332: 7329: 7327: 7324: 7322: 7319: 7317: 7314: 7312: 7311:Extreme point 7309: 7307: 7304: 7302: 7299: 7297: 7293: 7289: 7287: 7284: 7283: 7281: 7277: 7271: 7268: 7266: 7263: 7261: 7258: 7256: 7253: 7251: 7245: 7242: 7238: 7234: 7231: 7229: 7223: 7221: 7218: 7216: 7213: 7211: 7208: 7206: 7203: 7201: 7198: 7196: 7193: 7192: 7190: 7188:Types of sets 7186: 7179: 7175: 7172: 7168: 7165: 7163: 7160: 7158: 7155: 7154: 7153: 7150: 7146: 7143: 7141: 7138: 7136: 7133: 7132: 7131: 7128: 7124: 7121: 7119: 7116: 7114: 7111: 7109: 7106: 7104: 7101: 7099: 7096: 7095: 7094: 7091: 7087: 7084: 7082: 7079: 7077: 7074: 7072: 7069: 7067: 7064: 7063: 7062: 7059: 7057: 7054: 7052: 7051:Convex series 7049: 7047: 7046:Bochner space 7044: 7040: 7037: 7036: 7035: 7032: 7030: 7027: 7026: 7024: 7020: 7014: 7011: 7009: 7006: 7004: 7001: 6999: 6998:Riesz's lemma 6996: 6994: 6991: 6989: 6986: 6984: 6983:Mazur's lemma 6981: 6979: 6976: 6974: 6971: 6969: 6966: 6964: 6961: 6957: 6954: 6953: 6952: 6949: 6947: 6944: 6942: 6939: 6937: 6936:Gelfand–Mazur 6934: 6932: 6929: 6927: 6924: 6922: 6919: 6917: 6914: 6912: 6909: 6907: 6904: 6902: 6899: 6897: 6894: 6892: 6889: 6887: 6884: 6882: 6879: 6877: 6874: 6873: 6871: 6869: 6865: 6859: 6856: 6854: 6851: 6847: 6844: 6842: 6839: 6838: 6837: 6834: 6830: 6827: 6825: 6822: 6821: 6820: 6817: 6815: 6812: 6810: 6807: 6805: 6802: 6801: 6799: 6797: 6793: 6787: 6784: 6782: 6779: 6777: 6774: 6772: 6769: 6767: 6764: 6762: 6759: 6757: 6754: 6752: 6749: 6745: 6742: 6741: 6740: 6737: 6735: 6732: 6728: 6725: 6723: 6720: 6719: 6717: 6715: 6712: 6710: 6706: 6702: 6698: 6695: 6694: 6693: 6690: 6688: 6685: 6683: 6679: 6675: 6671: 6668: 6666: 6663: 6661: 6658: 6657: 6656: 6653: 6651: 6648: 6647: 6645: 6643: 6639: 6633: 6630: 6628: 6625: 6621: 6618: 6616: 6613: 6612: 6611: 6608: 6604: 6601: 6599: 6596: 6595: 6594: 6591: 6589: 6586: 6584: 6581: 6577: 6574: 6573: 6572: 6569: 6567: 6564: 6562: 6559: 6558: 6556: 6552: 6546: 6543: 6541: 6538: 6534: 6531: 6530: 6529: 6526: 6524: 6521: 6519: 6516: 6512: 6508: 6505: 6504: 6503: 6500: 6496: 6493: 6492: 6491: 6488: 6486: 6483: 6481: 6478: 6476: 6473: 6472: 6470: 6466: 6459: 6455: 6451: 6448: 6446: 6442: 6440: 6437: 6435:) convex 6434: 6431: 6429: 6426: 6424: 6420: 6418: 6415: 6413: 6410: 6408: 6404: 6400: 6396: 6393: 6391: 6388: 6387: 6386: 6383: 6381: 6380:Grothendieck 6378: 6376: 6373: 6369: 6366: 6365: 6364: 6361: 6359: 6356: 6355: 6353: 6349: 6344: 6337: 6332: 6330: 6325: 6323: 6318: 6317: 6314: 6302: 6294: 6293: 6290: 6284: 6281: 6279: 6276: 6274: 6273:Weak topology 6271: 6269: 6266: 6264: 6261: 6259: 6256: 6255: 6253: 6249: 6242: 6238: 6235: 6233: 6230: 6228: 6225: 6223: 6220: 6218: 6215: 6213: 6210: 6208: 6205: 6203: 6200: 6198: 6197:Index theorem 6195: 6193: 6190: 6188: 6185: 6183: 6180: 6179: 6177: 6173: 6167: 6164: 6162: 6159: 6158: 6156: 6154:Open problems 6152: 6146: 6143: 6141: 6138: 6136: 6133: 6131: 6128: 6126: 6123: 6121: 6118: 6117: 6115: 6111: 6105: 6102: 6100: 6097: 6095: 6092: 6090: 6087: 6085: 6082: 6080: 6077: 6075: 6072: 6070: 6067: 6065: 6062: 6060: 6057: 6056: 6054: 6050: 6044: 6041: 6039: 6036: 6034: 6031: 6029: 6026: 6024: 6021: 6019: 6016: 6014: 6011: 6009: 6006: 6004: 6001: 6000: 5998: 5996: 5992: 5982: 5979: 5977: 5974: 5972: 5969: 5966: 5962: 5958: 5955: 5953: 5950: 5948: 5945: 5944: 5942: 5938: 5932: 5929: 5927: 5924: 5922: 5919: 5917: 5914: 5912: 5909: 5907: 5904: 5902: 5899: 5897: 5894: 5892: 5889: 5887: 5884: 5883: 5880: 5877: 5873: 5868: 5864: 5860: 5853: 5848: 5846: 5841: 5839: 5834: 5833: 5830: 5818: 5815: 5813: 5810: 5808: 5805: 5803: 5800: 5798: 5795: 5793: 5790: 5788: 5785: 5783: 5780: 5778: 5775: 5773: 5770: 5768: 5765: 5763: 5760: 5758: 5755: 5753: 5750: 5748: 5745: 5742: 5738: 5735: 5733: 5730: 5728: 5725: 5724: 5722: 5718: 5712: 5709: 5708: 5706: 5702: 5696: 5693: 5691: 5688: 5686: 5683: 5681: 5678: 5676: 5673: 5671: 5668: 5666: 5663: 5661: 5658: 5656: 5653: 5652: 5650: 5648:Miscellaneous 5646: 5639: 5635: 5632: 5630: 5627: 5625: 5622: 5620: 5617: 5616: 5614: 5610: 5604: 5601: 5599: 5596: 5594: 5591: 5589: 5586: 5585: 5583: 5579: 5571: 5568: 5567: 5566: 5563: 5561: 5558: 5556: 5553: 5551: 5548: 5546: 5543: 5541: 5537: 5535: 5532: 5531: 5529: 5525: 5519: 5516: 5514: 5511: 5509: 5506: 5504: 5501: 5499: 5496: 5494: 5491: 5489: 5486: 5484: 5481: 5479: 5476: 5475: 5473: 5469: 5463: 5460: 5458: 5455: 5453: 5450: 5448: 5445: 5443: 5440: 5436: 5433: 5431: 5428: 5426: 5423: 5422: 5421: 5418: 5417: 5415: 5413:Decomposition 5411: 5405: 5402: 5400: 5397: 5395: 5392: 5390: 5387: 5385: 5382: 5380: 5377: 5376: 5374: 5372: 5368: 5362: 5359: 5357: 5354: 5351: 5349: 5346: 5343: 5341: 5338: 5335: 5333: 5330: 5329: 5327: 5323: 5317: 5314: 5312: 5309: 5307: 5304: 5302: 5299: 5297: 5294: 5292: 5289: 5287: 5284: 5283: 5281: 5277: 5271: 5268: 5266: 5263: 5261: 5258: 5256: 5253: 5251: 5248: 5246: 5243: 5241: 5238: 5236: 5233: 5231: 5228: 5226: 5223: 5222: 5220: 5216: 5212: 5208: 5201: 5196: 5194: 5189: 5187: 5182: 5181: 5178: 5169: 5165: 5161: 5155: 5151: 5147: 5143: 5139: 5137:0-226-54203-3 5133: 5129: 5124: 5120: 5118:0-521-53584-0 5114: 5110: 5106: 5102: 5098: 5097:Willis, G. A. 5093: 5089: 5087:0-387-97245-5 5083: 5079: 5075: 5071: 5070:Conway, J. B. 5067: 5063: 5061:0-387-06386-2 5057: 5053: 5049: 5045: 5041: 5039:0-521-38729-9 5035: 5030: 5029: 5023: 5019: 5018: 5010: 5009:Takesaki 1979 5005: 5002: 4997: 4993: 4989: 4985: 4981: 4977: 4973: 4969: 4965: 4958: 4955: 4951: 4946: 4943: 4939: 4934: 4932: 4928: 4924: 4919: 4916: 4909: 4901: 4894: 4891: 4884: 4880: 4877: 4874: 4871: 4865: 4862: 4856: 4853: 4852: 4848: 4846: 4844: 4825: 4814: 4810: 4803: 4797: 4792: 4788: 4775: 4761: 4758: 4755: 4752: 4740: 4734: 4726: 4722: 4710: 4705: 4703: 4662: 4659: 4656: 4653: 4650: 4647: 4625: 4621: 4615: 4611: 4607: 4602: 4594: 4591: 4581: 4567: 4564: 4556: 4534: 4511: 4508: 4505: 4502: 4477: 4474: 4452: 4448: 4438: 4432: 4427: 4419: 4416: 4406: 4392: 4389: 4386: 4383: 4380: 4377: 4355: 4351: 4347: 4342: 4338: 4334: 4329: 4321: 4318: 4315: 4305: 4302: 4286: 4283: 4280: 4260: 4257: 4252: 4247: 4242: 4238: 4234: 4225: 4224: 4223: 4209: 4203: 4200: 4195: 4183: 4167: 4155: 4153: 4140: 4131: 4119: 4099: 4079: 4071: 4067: 4062: 4049: 4040: 4031: 4028: 4025: 4019: 4013: 4007: 3995: 3986: 3966: 3960: 3928: 3916: 3896: 3887: 3864: 3858: 3852: 3849: 3843: 3831: 3783: 3751: 3728: 3720: 3698: 3666: 3657: 3654: 3648: 3642: 3623: 3620: 3617: 3614: 3605: 3591: 3585: 3557: 3553: 3532: 3512: 3487: 3467: 3464: 3450: 3430: 3424: 3418: 3412: 3406: 3403: 3397: 3394: 3388: 3368: 3348: 3339: 3325: 3322: 3314: 3295: 3269: 3244: 3221: 3195: 3167: 3163: 3143: 3099: 3096: 3088: 3087:maximal ideal 3072: 3052: 3032: 3019: 3003: 2991: 2989: 2953: 2946:this algebra 2933: 2925: 2922: 2919: 2899: 2874: 2871: 2868: 2843: 2840: 2820: 2817: 2814: 2811: 2791: 2771: 2762: 2748: 2739: 2726: 2720: 2717: 2714: 2711: 2705: 2699: 2693: 2687: 2681: 2661: 2638: 2632: 2629: 2626: 2618: 2602: 2582: 2559: 2553: 2533: 2524: 2511: 2502: 2496: 2490: 2487: 2478: 2472: 2466: 2446: 2440: 2434: 2426: 2411: 2391: 2388: 2382: 2376: 2368: 2352: 2349: 2346: 2343: 2334: 2321: 2316: 2312: 2308: 2298: 2294: 2279: 2271: 2262: 2256: 2253: 2250: 2247: 2239: 2220: 2216: 2200: 2177: 2171: 2163: 2160:and thus is 2147: 2144: 2121: 2076: 2056: 2053: 2028: 2025: 2022: 2002: 1995: 1976: 1970: 1950: 1947: 1944: 1941: 1933: 1927: 1919: 1903: 1900: 1880: 1860: 1840: 1837: 1817: 1797: 1777: 1769: 1765: 1762: 1759: 1755: 1752: 1748: 1744: 1743:zero divisors 1740: 1737: 1733: 1729: 1728: 1727: 1724: 1711: 1703: 1687: 1684: 1664: 1661: 1641: 1638: 1635: 1632: 1629: 1626: 1601: 1598: 1595: 1592: 1589: 1586: 1578: 1540: 1526: 1524: 1520: 1516: 1511: 1509: 1505: 1501: 1497: 1493: 1489: 1485: 1481: 1473: 1468: 1464: 1460: 1435: 1431: 1428: 1424: 1420: 1416: 1413: 1410: 1409:Hilbert space 1406: 1403: 1389: 1386: 1378: 1375: 1360: 1337: 1331: 1323: 1320: 1306: 1300: 1292: 1288: 1284: 1281: 1278: 1275: 1252: 1246: 1243: 1239: 1235: 1230: 1227: 1223: 1218: 1214: 1208: 1202: 1199: 1196: 1190: 1184: 1181: 1174: 1158: 1138: 1115: 1107: 1103: 1094: 1078: 1070: 1067: 1064: 1048: 1040: 1026: 1020: 1017: 1014: 1011: 991: 983: 979: 978:operator norm 963: 955: 952: 948: 945: 941: 937: 934: 930: 927: 923: 909: 905: 899: 895: 889: 885: 881: 878: 875: 870: 866: 860: 856: 851: 847: 843: 837: 833: 829: 826: 823: 818: 814: 809: 804: 798: 794: 790: 787: 784: 779: 775: 770: 742: 738: 722: 716: 691: 662: 647: 644: 640: 636: 621: 601: 593: 590: 586: 585: 584: 582: 579:is in fact a 563: 555: 551: 542: 538: 534: 518: 495: 487: 483: 474: 458: 451: 432: 424: 420: 407: 405: 403: 389: 380: 379:-adic numbers 366: 356: 354: 349: 347: 329: 325: 316: 298: 294: 285: 282: 264: 260: 251: 250:isometrically 235: 227: 223: 207: 204: 196: 193:if it has an 192: 187: 185: 180: 167: 164: 161: 158: 155: 152: 140: 130: 124: 115: 111: 100: 96: 92: 89:, that is, a 88: 84: 80: 76: 72: 56: 49: 45: 44:Stefan Banach 41: 37: 34:, especially 33: 19: 7765:Applications 7686: 7597: 7558: 7505: 7491: 7487: 7474: 7408: 7360: 7247:Linear cone 7240: 7236: 7225:Convex cone 7118:Paley–Wiener 6978:Mackey–Arens 6968:Krein–Milman 6921:Closed range 6916:Closed graph 6886:Banach–Mazur 6803: 6766:Self-adjoint 6670:sesquilinear 6403:Polynomially 6343:Banach space 6263:Balanced set 6237:Distribution 6175:Applications 6119: 6028:Krein–Milman 6013:Closed graph 5720:Applications 5550:Disk algebra 5404:Spectral gap 5279:Main results 5229: 5149: 5146:Takesaki, M. 5127: 5100: 5073: 5051: 5027: 5004: 4971: 4967: 4957: 4945: 4918: 4893: 4776: 4711:, that is, 4706: 4677: 4553:denotes the 4159: 4063: 3979:Explicitly, 3606: 3341:A character 3340: 3208:and the set 3017: 3016:be a unital 2995: 2763: 2740: 2525: 2335: 2111:with radius 1931: 1929: 1725: 1575:cannot be a 1527: 1512: 1484:power series 1477: 1093:Haar measure 706:) with norm 411: 357: 350: 314: 221: 190: 188: 181: 91:normed space 87:Banach space 83:normed field 39: 29: 7486:Continuous 7321:Linear span 7306:Convex hull 7286:Affine hull 7145:holomorphic 7081:holomorphic 7061:Derivatives 6951:Hahn–Banach 6891:Banach–Saks 6809:C*-algebras 6776:Trace class 6739:Functionals 6627:Ultrastrong 6540:Quasinormed 6192:Heat kernel 6182:Hardy space 6089:Trace class 6003:Hahn–Banach 5965:Topological 5747:Heat kernel 5447:Compression 5332:Isospectral 5022:Bollobás, B 4950:Conway 1990 4938:Conway 1990 4923:Conway 1990 3156:is closed, 3018:commutative 2425:holomorphic 2137:and center 1963:denoted by 1579:; that is, 1513:The set of 1434:quaternions 1173:convolution 926:quaternions 643:matrix norm 226:commutative 222:commutative 32:mathematics 7807:Categories 7239:), and (Hw 7140:continuous 7076:functional 6824:C*-algebra 6709:Continuous 6571:Dual space 6545:Stereotype 6523:Metrizable 6450:Projective 6125:C*-algebra 5940:Properties 5425:Continuous 5240:C*-algebra 5235:B*-algebra 4910:References 4843:C*-algebra 4495:and every 4467:for every 4301:involution 4066:semisimple 2861:such that 2015:such that 1758:Noetherian 1577:commutator 1474:Properties 1405:C*-algebra 951:continuous 940:continuous 637:becomes a 581:C*-algebra 541:involution 184:continuous 7698:Sobolev W 7641:Schwartz 7616:∞ 7577:∞ 7573:ℓ 7539:Ω 7525:λ 7383:Σ 7265:Symmetric 7200:Absorbing 7113:regulated 7093:Integrals 6946:Goldstine 6781:Transpose 6718:Fredholm 6588:Ultraweak 6576:Dual norm 6507:Seminorms 6475:Barrelled 6445:Injective 6433:Uniformly 6407:Reflexive 6099:Unbounded 6094:Transpose 6052:Operators 5981:Separable 5976:Reflexive 5961:Algebraic 5947:Barrelled 5211:-algebras 5168:0938-0396 4988:0002-9939 4829:‖ 4823:‖ 4820:‖ 4815:∗ 4807:‖ 4801:‖ 4793:∗ 4785:‖ 4756:∈ 4744:‖ 4738:‖ 4732:‖ 4727:∗ 4719:‖ 4709:isometric 4702:*-algebra 4657:∈ 4626:∗ 4616:∗ 4603:∗ 4565:λ 4538:¯ 4535:λ 4506:∈ 4478:∈ 4475:λ 4453:∗ 4442:¯ 4439:λ 4428:∗ 4417:λ 4387:∈ 4356:∗ 4343:∗ 4330:∗ 4284:∈ 4253:∗ 4243:∗ 4207:→ 4196:∗ 4126:Δ 4035:Δ 4032:∈ 4029:χ 4014:χ 3999:^ 3987:σ 3955:Δ 3923:Δ 3891:^ 3853:χ 3844:χ 3835:^ 3821:given by 3778:Δ 3755:^ 3702:^ 3670:^ 3658:σ 3643:σ 3618:∈ 3580:Δ 3558:∗ 3451:χ 3419:χ 3407:χ 3389:χ 3349:χ 3290:Δ 3216:Δ 2926:λ 2875:λ 2872:− 2844:∈ 2841:λ 2833:there is 2815:∈ 2718:∈ 2682:σ 2630:∈ 2497:σ 2467:σ 2435:σ 2389:∈ 2347:∈ 2305:‖ 2291:‖ 2286:∞ 2283:→ 2257:σ 2254:∈ 2251:λ 2240:λ 2221:formula: 2215:non-empty 2172:σ 2125:‖ 2119:‖ 2029:λ 2026:− 2003:λ 1971:σ 1945:∈ 1636:∈ 1602:≠ 1593:− 1285:∈ 1247:μ 1228:− 1200:∫ 1139:μ 1079:μ 1066:Hausdorff 1024:∞ 1015:⁡ 879:… 827:… 788:… 720:‖ 714:‖ 539:being an 162:∈ 144:‖ 138:‖ 134:‖ 128:‖ 125:≤ 119:‖ 109:‖ 81:complete 69:over the 7634:weighted 7504:Hilbert 7481:Bs space 7351:Examples 7316:Interior 7292:Relative 7270:Zonotope 7249:(subset) 7227:(subset) 7178:Strongly 7157:Lebesgue 7152:Measures 7022:Analysis 6868:Theorems 6819:Spectrum 6744:positive 6727:operator 6665:operator 6655:Bilinear 6620:operator 6603:operator 6583:Operator 6480:Complete 6428:Strictly 6301:Category 6113:Algebras 5995:Theorems 5952:Complete 5921:Schwartz 5867:glossary 5812:Weyl law 5757:Lax pair 5704:Examples 5538:With an 5457:Discrete 5435:Residual 5371:Spectrum 5356:operator 5348:operator 5340:operator 5255:Spectrum 5148:(1979). 5099:(2003). 5072:(1990). 5024:(1990). 4849:See also 4640:for all 4370:for all 4273:for all 3607:For any 3282:The set 1932:spectrum 1702:spectrum 1519:open set 1490:and the 1478:Several 1458:numbers. 1421:on some 933:supremum 635:matrices 408:Examples 353:spectrum 315:a priori 95:complete 93:that is 46:, is an 7499:Hardy H 7402:c space 7339:)  7294:)  7215:Bounded 7103:Dunford 7098:Bochner 7071:Gateaux 7066:FrĂ©chet 6841:of ODEs 6786:Unitary 6761:Nuclear 6692:Compact 6682:Bounded 6650:Adjoint 6490:FrĂ©chet 6485:F-space 6456: ( 6452:)  6405:)  6385:Hilbert 6358:Asplund 6104:Unitary 6084:Nuclear 6069:Compact 6064:Bounded 6059:Adjoint 6033:Min–max 5926:Sobolev 5911:Nuclear 5901:Hilbert 5896:FrĂ©chet 5861: ( 5353:Unitary 4996:2160559 3717:is the 2162:compact 1994:scalars 1131:of all 1091:is its 533:compact 471:, that 97:in the 75:complex 7415:Besov 7255:Radial 7220:Convex 7205:Affine 7174:Weakly 7167:Vector 7039:bundle 6829:radius 6756:Normal 6722:kernel 6687:Closed 6610:Strong 6528:Normed 6518:Mackey 6363:Banach 6345:topics 6079:Normal 5916:Orlicz 5906:Hölder 5886:Banach 5875:Spaces 5863:topics 5337:Normal 5166:  5156:  5134:  5115:  5084:  5058:  5036:  4994:  4986:  4524:here, 3688:where 3045:Since 2619:. For 2336:Given 1751:closed 954:linear 639:unital 535:. The 281:closed 191:unital 122:  99:metric 7490:with 7337:Quasi 7331:Polar 7135:Borel 7086:quasi 6615:polar 6598:polar 6412:Riesz 5891:Besov 5430:Point 4992:JSTOR 4885:Notes 4841:is a 1553:then 1061:is a 284:ideal 7488:C(K) 7123:weak 6660:form 6593:Weak 6566:Dual 6533:norm 6495:tame 6368:list 6239:(or 5957:Dual 5361:Unit 5209:and 5164:ISSN 5154:ISBN 5132:ISBN 5113:ISBN 5082:ISBN 5056:ISBN 5034:ISBN 4984:ISSN 4112:and 2996:Let 2764:Let 2365:the 1677:and 1268:for 1071:and 924:The 677:(or 614:-by- 220:and 71:real 38:, a 6705:Dis 5105:doi 4976:doi 4972:123 4557:of 3799:to 3721:of 3500:to 3257:to 3136:in 3089:of 2276:lim 2229:sup 2213:is 1893:of 1749:is 1461:An 1041:If 1012:dim 984:on 727:max 531:is 286:of 73:or 30:In 7809:: 7475:BV 7409:BK 7361:AC 7243:)) 7176:/ 6678:Un 5865:– 5162:. 5111:. 5080:. 4990:. 4982:. 4970:. 4966:. 4930:^ 4845:. 4704:. 4303:). 3468:1. 1738:.) 1712:0. 543:, 475:. 404:. 7745:) 7740:p 7736:L 7732:, 7729:X 7726:( 7723:W 7687:F 7668:) 7663:n 7658:R 7653:( 7649:S 7612:L 7598:L 7559:â„“ 7542:) 7536:( 7531:p 7528:, 7521:L 7506:H 7492:K 7452:) 7448:R 7444:( 7439:s 7434:q 7431:, 7428:p 7424:B 7386:) 7380:( 7377:a 7374:b 7335:( 7290:( 7241:x 7237:x 6707:) 6703:( 6680:) 6676:( 6509:/ 6460:) 6443:( 6423:B 6421:( 6401:( 6335:e 6328:t 6321:v 6243:) 5967:) 5963:/ 5959:( 5869:) 5851:e 5844:t 5837:v 5743:) 5739:( 5640:) 5636:( 5199:e 5192:t 5185:v 5170:. 5140:. 5121:. 5107:: 5090:. 5064:. 5042:. 4998:. 4978:: 4902:. 4826:x 4811:x 4804:= 4798:x 4789:x 4762:. 4759:A 4753:x 4741:x 4735:= 4723:x 4687:C 4663:. 4660:A 4654:y 4651:, 4648:x 4622:x 4612:y 4608:= 4599:) 4595:y 4592:x 4589:( 4568:. 4512:; 4509:A 4503:x 4482:C 4449:x 4433:= 4424:) 4420:x 4414:( 4393:. 4390:A 4384:y 4381:, 4378:x 4352:y 4348:+ 4339:x 4335:= 4326:) 4322:y 4319:+ 4316:x 4313:( 4287:A 4281:x 4261:x 4258:= 4248:) 4239:x 4235:( 4210:A 4204:A 4201:: 4168:A 4141:. 4138:) 4135:) 4132:A 4129:( 4123:( 4120:C 4100:A 4080:A 4050:. 4047:} 4044:) 4041:A 4038:( 4026:: 4023:) 4020:x 4017:( 4011:{ 4008:= 4005:) 3996:x 3990:( 3967:. 3964:) 3961:A 3958:( 3935:) 3932:) 3929:A 3926:( 3920:( 3917:C 3897:, 3888:x 3865:. 3862:) 3859:x 3856:( 3850:= 3847:) 3841:( 3832:x 3808:C 3787:) 3784:A 3781:( 3752:x 3729:x 3699:x 3676:) 3667:x 3661:( 3655:= 3652:) 3649:x 3646:( 3624:, 3621:A 3615:x 3592:, 3589:) 3586:A 3583:( 3554:A 3533:A 3513:, 3509:C 3488:A 3465:= 3462:) 3458:1 3454:( 3431:, 3428:) 3425:b 3422:( 3416:) 3413:a 3410:( 3404:= 3401:) 3398:b 3395:a 3392:( 3369:A 3326:, 3323:A 3299:) 3296:A 3293:( 3270:. 3266:C 3245:A 3225:) 3222:A 3219:( 3196:A 3174:m 3168:/ 3164:A 3144:A 3122:m 3100:. 3097:A 3073:A 3053:A 3033:. 3029:C 3004:A 2975:C 2954:A 2934:: 2930:1 2923:= 2920:a 2900:a 2879:1 2869:a 2848:C 2821:, 2818:A 2812:a 2792:x 2772:A 2749:x 2727:. 2724:} 2721:X 2715:t 2712:: 2709:) 2706:t 2703:( 2700:f 2697:{ 2694:= 2691:) 2688:f 2685:( 2662:X 2642:) 2639:X 2636:( 2633:C 2627:f 2603:A 2583:X 2563:) 2560:X 2557:( 2554:L 2534:A 2512:. 2509:) 2506:) 2503:x 2500:( 2494:( 2491:f 2488:= 2485:) 2482:) 2479:x 2476:( 2473:f 2470:( 2447:. 2444:) 2441:x 2438:( 2412:f 2392:A 2386:) 2383:x 2380:( 2377:f 2353:, 2350:A 2344:x 2322:. 2317:n 2313:/ 2309:1 2299:n 2295:x 2280:n 2272:= 2269:} 2266:) 2263:x 2260:( 2248:: 2244:| 2236:| 2232:{ 2201:x 2181:) 2178:x 2175:( 2148:, 2145:0 2122:x 2098:C 2077:x 2057:. 2054:A 2033:1 2023:x 1980:) 1977:x 1974:( 1951:, 1948:A 1942:x 1904:. 1901:A 1881:B 1861:A 1841:. 1838:B 1818:A 1798:A 1778:B 1688:x 1685:y 1665:y 1662:x 1642:. 1639:A 1633:y 1630:, 1627:x 1606:1 1599:x 1596:y 1590:y 1587:x 1562:1 1541:, 1537:1 1469:. 1444:H 1429:. 1411:. 1390:. 1387:X 1361:X 1341:) 1338:X 1335:( 1332:C 1307:. 1304:) 1301:G 1298:( 1293:1 1289:L 1282:y 1279:, 1276:x 1256:) 1253:h 1250:( 1244:d 1240:) 1236:g 1231:1 1224:h 1219:( 1215:y 1212:) 1209:h 1206:( 1203:x 1197:= 1194:) 1191:g 1188:( 1185:y 1182:x 1159:G 1119:) 1116:G 1113:( 1108:1 1104:L 1049:G 1027:. 1021:= 1018:E 992:E 964:E 910:. 906:) 900:n 896:y 890:n 886:x 882:, 876:, 871:1 867:y 861:1 857:x 852:( 848:= 844:) 838:n 834:y 830:, 824:, 819:1 815:y 810:( 805:) 799:n 795:x 791:, 785:, 780:1 776:x 771:( 749:| 743:i 739:x 734:| 723:= 717:x 692:n 687:C 663:n 658:R 645:. 622:n 602:n 591:. 567:) 564:X 561:( 556:0 552:C 519:X 499:) 496:X 493:( 488:0 484:C 459:X 436:) 433:X 430:( 425:0 421:C 390:p 367:p 330:e 326:A 299:e 295:A 265:e 261:A 236:A 208:, 205:1 168:. 165:A 159:y 156:, 153:x 141:y 131:x 116:y 112:x 57:A 20:)

Index

Structure space
mathematics
functional analysis
Stefan Banach
associative algebra
real
complex
non-Archimedean
normed field
Banach space
normed space
complete
metric
continuous
identity element
commutative
isometrically
closed
ideal
trigonometric functions
spectrum
p {\displaystyle p} -adic numbers
p {\displaystyle p} -adic analysis
locally compact Hausdorff space
vanish at infinity
compact
complex conjugation
involution
C*-algebra
absolute value

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