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Discontinuous linear map

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The argument for the existence of discontinuous linear maps on normed spaces can be generalized to all metrizable topological vector spaces, especially to all Fréchet spaces, but there exist infinite-dimensional locally convex topological vector spaces such that every functional is continuous. On the
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of a topological vector space is the collection of continuous linear maps from the space into the underlying field. Thus the failure of some linear maps to be continuous for infinite-dimensional normed spaces implies that for these spaces, one needs to distinguish the algebraic dual space from the
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The upshot is that the existence of discontinuous linear maps depends on AC; it is consistent with set theory without AC that there are no discontinuous linear maps on complete spaces. In particular, no concrete construction such as the derivative can succeed in defining a discontinuous linear map
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So the natural question to ask about linear operators that are not everywhere-defined is whether they are closable. The answer is, "not necessarily"; indeed, every infinite-dimensional normed space admits linear operators that are not closable. As in the case of discontinuous operators considered
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function is continuous (this is to be understood in the terminology of constructivism, according to which only representable functions are considered to be functions). Such stances are held by only a small minority of working mathematicians.
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Notice that by using the fact that any set of linearly independent vectors can be completed to a basis, we implicitly used the axiom of choice, which was not needed for the concrete example in the previous section.
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continuous dual space which is then a proper subset. It illustrates the fact that an extra dose of caution is needed in doing analysis on infinite-dimensional spaces as compared to finite-dimensional ones.
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viewpoint. For example, H. G. Garnir, in searching for so-called "dream spaces" (topological vector spaces on which every linear map into a normed space is continuous), was led to adopt ZF +
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Solovay's result shows that it is not necessary to assume that all infinite-dimensional vector spaces admit discontinuous linear maps, and there are schools of analysis which adopt a more
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This example can be extended into a general theorem about the existence of discontinuous linear maps on any infinite-dimensional normed space (as long as the codomain is not trivial).
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closed operator on a complete domain is continuous, so to obtain a discontinuous closed operator, one must permit operators which are not defined everywhere.
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in which every set of reals is measurable. This implies that there are no discontinuous linear real functions. Clearly AC does not hold in the model.
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which assigns to each function its derivative is similarly discontinuous. Note that although the derivative operator is not continuous, it is
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The fact that the domain is not complete here is important: discontinuous operators on complete spaces require a little more work.
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One can consider even more general spaces. For example, the existence of a homomorphism between complete separable metric
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is infinite-dimensional, to show the existence of a linear functional which is not continuous then amounts to constructing
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Examples of discontinuous linear maps are easy to construct in spaces that are not complete; on any Cauchy sequence
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grow without bound. In a sense, the linear operators are not continuous because the space has "holes".
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above, the proof requires the axiom of choice and so is in general nonconstructive, though again, if
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That is, in studying operators that are not everywhere-defined, one may restrict one's attention to
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Discontinuous linear maps can be proven to exist more generally, even if the space is complete. Let
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real function is linear if and only if it is measurable, so for every such function there is a
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For example, the weak topology w.r.t. the space of all (algebraically) linear functionals.
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of linearly independent vectors which does not have a limit, there is a linear operator
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from which it follows that these spaces are nonconvex. Note that here is indicated the
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and with real values, is linear, but not continuous. Indeed, consider the sequence
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is not complete here, as must be the case when there is such a constructible map.
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is infinite-dimensional, this proof will fail as there is no guarantee that the
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In fact, there is even an example of a linear operator whose graph has closure
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acts as the identity on the rest of the Hamel basis, and extend to all of
1675:{\displaystyle T(f_{n})={\frac {n^{2}\cos(n^{2}\cdot 0)}{n}}=n\to \infty } 4894: 4879: 4772: 4666: 4661: 4646: 4625: 4589: 4496: 4316: 4135: 4125: 4032: 3834: 1891: 1883: 1584:. This sequence converges uniformly to the constantly zero function, but 17: 1161:
is the zero map which is trivially continuous. In all other cases, when
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so this provides a sort of maximally discontinuous linear map (confer
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and are often used as approximations to more general functions (see
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A linear map from a finite-dimensional space is always continuous
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is not the zero space. We will find a discontinuous linear map
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which states, among other things, that any linear map from an
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is not the zero space, one can find a discontinuous map from
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and so is continuous. In fact, to see this, simply note that
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Many naturally occurring linear discontinuous operators are
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Complete this sequence of linearly independent vectors to a
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any two norms on a finite-dimensional space are equivalent
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This non-locally convex space has a trivial dual space.
859:{\displaystyle \|f(x)-f(x')\|=\|f(x-x')\|\leq K\|x-x'\|} 3642:
Pages displaying short descriptions of redirect targets
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is a negation of strong AC) as his axioms to prove the
194:{\displaystyle \left(e_{1},e_{2},\ldots ,e_{n}\right)} 52:
topological vector spaces (e.g., infinite-dimensional
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Going to the extreme of 1767:, as would hold for a continuous map. Note that 597:{\displaystyle \sum _{i=1}^{n}|x_{i}|\leq C\|x\|} 48:. It turns out that for maps defined on infinite- 4972: 2034:be any sequence of rationals which converges to 1346: 478: 2566: 2551:at the other vectors in the basis to be zero. 4271: 3787: 2616:(dependent choice is a weakened form and the 205:which may be taken to be unit vectors. Then, 3528: 3522: 2487: 2474: 2181: 1877: 1339: 1333: 1282: 1269: 1261: 1239: 1153:is the zero space {0}, the only map between 853: 836: 827: 801: 795: 760: 709: 703: 634: 619: 591: 585: 524:{\displaystyle M=\sup _{i}\{\|f(e_{i})\|\},} 515: 512: 490: 487: 448: 426: 316: 301: 3236:the space of polynomial functions from to 2389:which is not bounded. For that, consider a 56:), the answer is generally no: there exist 4278: 4264: 3794: 3780: 3649: â€“ Type of function in linear algebra 1401:{\displaystyle \|f\|=\sup _{x\in }|f(x)|.} 68:and does not provide an explicit example. 28:which preserve the algebraic structure of 3706: 3379: 3326: 3286:, the graph of this operator is dense in 3244: 3218: 2490: 2244: 2216: 2141: 2119: 2005: 1936: 1454: 4084:Group algebra of a locally compact group 3758:Handbook of Analysis and its Foundations 3710:Handbook of Analysis and Its Foundations 3045:{\displaystyle {\overline {\Gamma (T)}}} 2978:{\displaystyle {\overline {\Gamma (T)}}} 2848:{\displaystyle \operatorname {Dom} (T).} 2756:{\displaystyle \operatorname {Dom} (T),} 3666: 3339: 3202:Such an operator is not closable. Let 926:{\displaystyle \delta \leq \epsilon /K} 608:>0 which follows from the fact that 4973: 4417:Uniform boundedness (Banach–Steinhaus) 3504:which do have nontrivial dual spaces. 3398:{\displaystyle L^{p}(\mathbb {R} ,dx)} 2442:, which we normalize. Then, we define 1288:{\displaystyle \|T(e_{i})\|/\|e_{i}\|} 4259: 3775: 3628:can also be shown nonconstructively. 3052:is itself the graph of some operator 2494:{\displaystyle T(e_{n})=n\|e_{n}\|\,} 1787:is real-valued, and so is actually a 1180: 3270:which takes the polynomial function 36:). If the spaces involved are also 24:form an important class of "simple" 3445:on the real line. There are other 2648: 1949:{\displaystyle f:\mathbb {R} \to R} 13: 3741:Constantin Costara, Dumitru Popa, 3024: 2957: 2947:. Otherwise, consider its closure 2869: 2622:Garnir–Wright closed graph theorem 2374:is an arbitrary nonzero vector in 2155:), but not continuous. Note that 1898:vector space). Note that any two 1760:{\displaystyle T(f_{n})\to T(0)=0} 1697: 1669: 60:. If the domain of definition is 14: 5002: 2816:We don't lose much if we replace 1079:{\displaystyle B(f(x),\epsilon )} 4955: 4954: 4240: 4239: 4166:Topological quantum field theory 3743:Exercises in Functional Analysis 3075:{\displaystyle {\overline {T}},} 2645:everywhere on a complete space. 1298:For example, consider the space 4942:With the approximation property 3713:, Academic Press, p. 136, 3125:{\displaystyle {\overline {T}}} 2254:{\displaystyle K=\mathbb {C} .} 2175:relies on the axiom of choice. 892:{\displaystyle \epsilon >0,} 4405:Open mapping (Banach–Schauder) 3727: 3700: 3660: 3638:Finest locally convex topology 3595: 3591: 3585: 3578: 3565: 3561: 3555: 3548: 3392: 3375: 3033: 3027: 2966: 2960: 2878: 2872: 2839: 2833: 2797: 2788: 2782: 2747: 2741: 2465: 2452: 2340:{\displaystyle g(x)=f(x)y_{0}} 2324: 2318: 2309: 2303: 2223:{\displaystyle K=\mathbb {R} } 2088: 2082: 1972: 1966: 1940: 1851: 1748: 1742: 1736: 1733: 1720: 1694: 1666: 1651: 1632: 1607: 1594: 1539: 1523: 1508: 1502: 1451: 1445: 1431: 1425: 1391: 1387: 1381: 1374: 1368: 1356: 1258: 1245: 1122: 1116: 1073: 1064: 1058: 1052: 1029: 1017: 994: 985: 979: 973: 964: 961: 949: 943: 824: 807: 792: 781: 772: 766: 682: 667: 631: 625: 575: 560: 509: 496: 445: 432: 422: 407: 378: 374: 361: 323: 313: 307: 274: 261: 221: 215: 100: 1: 3962:Uniform boundedness principle 3653: 2532:{\displaystyle n=1,2,\ldots } 1811:(an element of the algebraic 3434:{\displaystyle 0<p<1,} 3251:{\displaystyle \mathbb {R} } 3225:{\displaystyle \mathbb {R} } 3117: 3064: 3037: 2970: 2859:without loss of generality. 2265:is infinite-dimensional and 2148:{\displaystyle \mathbb {R} } 2126:{\displaystyle \mathbb {Q} } 2012:{\displaystyle \mathbb {R} } 1703:{\displaystyle n\to \infty } 1458:{\displaystyle T(f)=f'(0)\,} 1165:is infinite-dimensional and 1086:are the normed balls around 1035:{\displaystyle B(x,\delta )} 866:for some universal constant 7: 4626:Radially convex/Star-shaped 4611:Pre-compact/Totally bounded 3631: 3497:{\displaystyle 0<p<1} 3317:nowhere continuous function 2589:On the other hand, in 1970 2567:Role of the axiom of choice 1886:as a vector space over the 1882:An algebraic basis for the 1135:), which gives continuity. 10: 5007: 4312:Continuous linear operator 4105:Invariant subspace problem 3511:on the unit interval with 3308:{\displaystyle X\times Y,} 3195:{\displaystyle X\times Y.} 3007:{\displaystyle X\times Y.} 2933:{\displaystyle X\times Y,} 2884:{\displaystyle \Gamma (T)} 2100:{\displaystyle f(\pi )=0.} 1987:{\displaystyle f(\pi )=0,} 1322:on the interval with the 4950: 4695: 4657:Algebraic interior (core) 4639: 4537: 4425: 4399:Vector-valued Hahn–Banach 4360: 4294: 4287:Topological vector spaces 4235: 4194: 4118: 4097: 4056: 3995: 3937: 3883: 3825: 3818: 3284:Stone–Weierstrass theorem 3258:. They are subspaces of 2857:densely defined operators 2668:To be more concrete, let 2182:General existence theorem 1878:A nonconstructive example 1232:such that the quantities 753:is linear, and therefore 84:be two normed spaces and 58:discontinuous linear maps 42:topological vector spaces 4487:Topological homomorphism 4347:Topological vector space 4074:Spectrum of a C*-algebra 3760:, Academic Press, 1997. 3707:Schechter, Eric (1996), 3353:associates a continuous 531:and using the fact that 109:{\displaystyle f:X\to Y} 4171:Noncommutative geometry 2427:{\displaystyle n\geq 1} 2171:. The construction of 1577:{\displaystyle n\geq 1} 747:bounded linear operator 4991:Functions and mappings 4545:Absolutely convex/disk 4227:Tomita–Takesaki theory 4202:Approximation property 4146:Calculus of variations 3615: 3498: 3466: 3435: 3399: 3327:Impact for dual spaces 3309: 3252: 3226: 3196: 3153: 3126: 3095: 3076: 3046: 3008: 2979: 2934: 2905: 2885: 2849: 2810: 2757: 2722: 2702: 2682: 2533: 2495: 2428: 2368: 2341: 2255: 2224: 2149: 2127: 2101: 2048: 2013: 1988: 1950: 1916: 1861: 1860:{\displaystyle X\to X} 1835: 1805: 1781: 1761: 1704: 1676: 1578: 1552: 1479: 1459: 1402: 1312: 1289: 1226: 1206: 1129: 1100: 1080: 1036: 1001: 927: 893: 860: 739: 719: 665: 598: 558: 525: 458: 405: 347: 284: 247: 195: 110: 4580:Complemented subspace 4394:hyperplane separation 4222:Banach–Mazur distance 4185:Generalized functions 3673:Annals of Mathematics 3616: 3499: 3467: 3465:{\displaystyle L^{p}} 3436: 3400: 3310: 3253: 3227: 3197: 3154: 3127: 3096: 3077: 3047: 3009: 2980: 2935: 2906: 2886: 2850: 2811: 2758: 2723: 2703: 2683: 2534: 2496: 2429: 2369: 2367:{\displaystyle y_{0}} 2342: 2293:given by the formula 2256: 2225: 2150: 2128: 2102: 2049: 2014: 1989: 1951: 1917: 1862: 1836: 1834:{\displaystyle X^{*}} 1806: 1782: 1762: 1705: 1677: 1579: 1553: 1480: 1460: 1403: 1313: 1290: 1227: 1207: 1205:{\displaystyle e_{i}} 1130: 1101: 1081: 1037: 1002: 928: 894: 861: 740: 720: 645: 599: 538: 526: 459: 385: 327: 285: 227: 196: 111: 4830:Locally convex space 4380:Closed graph theorem 4332:Locally convex space 3967:Kakutani fixed-point 3952:Riesz representation 3519: 3509:measurable functions 3476: 3449: 3410: 3362: 3340:Beyond normed spaces 3290: 3240: 3214: 3208:polynomial functions 3177: 3140: 3109: 3085: 3056: 3018: 2989: 2951: 2915: 2895: 2866: 2824: 2767: 2732: 2712: 2692: 2672: 2659:closed graph theorem 2636:, which states that 2571:As noted above, the 2505: 2446: 2436:linearly independent 2412: 2351: 2297: 2234: 2206: 2137: 2115: 2076: 2047:{\displaystyle \pi } 2038: 2019:by linearity. Let { 2001: 1960: 1926: 1915:{\displaystyle \pi } 1906: 1845: 1818: 1795: 1771: 1714: 1688: 1588: 1562: 1489: 1469: 1419: 1330: 1302: 1236: 1216: 1189: 1128:{\displaystyle f(x)} 1110: 1090: 1046: 1011: 937: 903: 874: 757: 729: 616: 535: 468: 298: 209: 136: 88: 34:linear approximation 4981:Functional analysis 4810:Interpolation space 4342:Operator topologies 4151:Functional calculus 4110:Mahler's conjecture 4089:Von Neumann algebra 3803:Functional analysis 3347:Hahn–Banach theorem 1902:numbers, say 1 and 1841:). The linear map 292:triangle inequality 4840:(Pseudo)Metrizable 4672:Minkowski addition 4524:Sublinear function 4176:Riemann hypothesis 3875:Topological vector 3745:, Springer, 2003. 3668:Solovay, Robert M. 3647:Sublinear function 3611: 3494: 3462: 3431: 3395: 3305: 3248: 3222: 3192: 3152:{\displaystyle T.} 3149: 3122: 3091: 3072: 3042: 3004: 2975: 2930: 2901: 2881: 2845: 2820:by the closure of 2806: 2753: 2718: 2698: 2678: 2663:everywhere-defined 2541:vector space basis 2529: 2491: 2424: 2364: 2337: 2251: 2220: 2145: 2123: 2097: 2044: 2009: 1984: 1946: 1912: 1857: 1831: 1801: 1777: 1757: 1700: 1672: 1574: 1548: 1475: 1455: 1398: 1372: 1308: 1285: 1222: 1202: 1181:A concrete example 1125: 1096: 1076: 1032: 997: 923: 889: 856: 735: 715: 594: 521: 486: 454: 280: 191: 130:finite-dimensional 116:a linear map from 106: 38:topological spaces 4968: 4967: 4687:Relative interior 4433:Bilinear operator 4317:Linear functional 4253: 4252: 4156:Integral operator 3933: 3932: 3756:Schechter, Eric, 3676:, Second Series, 3600: 3355:linear functional 3120: 3094:{\displaystyle T} 3067: 3040: 2973: 2904:{\displaystyle T} 2721:{\displaystyle Y} 2701:{\displaystyle X} 2681:{\displaystyle T} 2591:Robert M. Solovay 2107:By construction, 1804:{\displaystyle X} 1789:linear functional 1780:{\displaystyle T} 1658: 1546: 1478:{\displaystyle X} 1345: 1311:{\displaystyle X} 1225:{\displaystyle T} 1099:{\displaystyle x} 738:{\displaystyle f} 477: 132:, choose a basis 4998: 4958: 4957: 4932:Uniformly smooth 4601: 4593: 4560:Balanced/Circled 4550:Absorbing/Radial 4280: 4273: 4266: 4257: 4256: 4243: 4242: 4161:Jones polynomial 4079:Operator algebra 3823: 3822: 3796: 3789: 3782: 3773: 3772: 3734: 3731: 3725: 3723: 3704: 3698: 3696: 3664: 3643: 3620: 3618: 3617: 3612: 3601: 3599: 3598: 3581: 3569: 3568: 3551: 3545: 3543: 3542: 3503: 3501: 3500: 3495: 3471: 3469: 3468: 3463: 3461: 3460: 3443:Lebesgue measure 3440: 3438: 3437: 3432: 3404: 3402: 3401: 3396: 3382: 3374: 3373: 3345:other hand, the 3314: 3312: 3311: 3306: 3257: 3255: 3254: 3249: 3247: 3231: 3229: 3228: 3223: 3221: 3206:be the space of 3201: 3199: 3198: 3193: 3158: 3156: 3155: 3150: 3131: 3129: 3128: 3123: 3121: 3113: 3100: 3098: 3097: 3092: 3081: 3079: 3078: 3073: 3068: 3060: 3051: 3049: 3048: 3043: 3041: 3036: 3022: 3013: 3011: 3010: 3005: 2984: 2982: 2981: 2976: 2974: 2969: 2955: 2939: 2937: 2936: 2931: 2910: 2908: 2907: 2902: 2890: 2888: 2887: 2882: 2854: 2852: 2851: 2846: 2815: 2813: 2812: 2807: 2762: 2760: 2759: 2754: 2727: 2725: 2724: 2719: 2707: 2705: 2704: 2699: 2687: 2685: 2684: 2679: 2661:asserts that an 2649:Closed operators 2634:Ceitin's theorem 2538: 2536: 2535: 2530: 2500: 2498: 2497: 2492: 2486: 2485: 2464: 2463: 2433: 2431: 2430: 2425: 2373: 2371: 2370: 2365: 2363: 2362: 2346: 2344: 2343: 2338: 2336: 2335: 2260: 2258: 2257: 2252: 2247: 2229: 2227: 2226: 2221: 2219: 2154: 2152: 2151: 2146: 2144: 2132: 2130: 2129: 2124: 2122: 2106: 2104: 2103: 2098: 2053: 2051: 2050: 2045: 2018: 2016: 2015: 2010: 2008: 1993: 1991: 1990: 1985: 1955: 1953: 1952: 1947: 1939: 1921: 1919: 1918: 1913: 1900:noncommensurable 1866: 1864: 1863: 1858: 1840: 1838: 1837: 1832: 1830: 1829: 1810: 1808: 1807: 1802: 1786: 1784: 1783: 1778: 1766: 1764: 1763: 1758: 1732: 1731: 1709: 1707: 1706: 1701: 1681: 1679: 1678: 1673: 1659: 1654: 1644: 1643: 1625: 1624: 1614: 1606: 1605: 1583: 1581: 1580: 1575: 1557: 1555: 1554: 1549: 1547: 1542: 1535: 1534: 1515: 1501: 1500: 1484: 1482: 1481: 1476: 1464: 1462: 1461: 1456: 1444: 1407: 1405: 1404: 1399: 1394: 1377: 1371: 1320:smooth functions 1317: 1315: 1314: 1309: 1294: 1292: 1291: 1286: 1281: 1280: 1268: 1257: 1256: 1231: 1229: 1228: 1223: 1211: 1209: 1208: 1203: 1201: 1200: 1134: 1132: 1131: 1126: 1105: 1103: 1102: 1097: 1085: 1083: 1082: 1077: 1041: 1039: 1038: 1033: 1006: 1004: 1003: 998: 932: 930: 929: 924: 919: 898: 896: 895: 890: 865: 863: 862: 857: 852: 823: 791: 744: 742: 741: 736: 724: 722: 721: 716: 690: 686: 685: 680: 679: 670: 664: 659: 603: 601: 600: 595: 578: 573: 572: 563: 557: 552: 530: 528: 527: 522: 508: 507: 485: 463: 461: 460: 455: 444: 443: 425: 420: 419: 410: 404: 399: 381: 377: 373: 372: 357: 356: 346: 341: 289: 287: 286: 281: 273: 272: 257: 256: 246: 241: 200: 198: 197: 192: 190: 186: 185: 184: 166: 165: 153: 152: 115: 113: 112: 107: 5006: 5005: 5001: 5000: 4999: 4997: 4996: 4995: 4986:Axiom of choice 4971: 4970: 4969: 4964: 4946: 4708:B-complete/Ptak 4691: 4635: 4599: 4591: 4570:Bounding points 4533: 4475:Densely defined 4421: 4410:Bounded inverse 4356: 4290: 4284: 4254: 4249: 4231: 4195:Advanced topics 4190: 4114: 4093: 4052: 4018:Hilbert–Schmidt 3991: 3982:Gelfand–Naimark 3929: 3879: 3814: 3800: 3738: 3737: 3732: 3728: 3721: 3705: 3701: 3686:10.2307/1970696 3665: 3661: 3656: 3641: 3634: 3594: 3577: 3570: 3564: 3547: 3546: 3544: 3538: 3534: 3520: 3517: 3516: 3477: 3474: 3473: 3456: 3452: 3450: 3447: 3446: 3411: 3408: 3407: 3378: 3369: 3365: 3363: 3360: 3359: 3351:Minkowski gauge 3342: 3329: 3291: 3288: 3287: 3243: 3241: 3238: 3237: 3217: 3215: 3212: 3211: 3178: 3175: 3174: 3141: 3138: 3137: 3112: 3110: 3107: 3106: 3086: 3083: 3082: 3059: 3057: 3054: 3053: 3023: 3021: 3019: 3016: 3015: 2990: 2987: 2986: 2956: 2954: 2952: 2949: 2948: 2916: 2913: 2912: 2896: 2893: 2892: 2867: 2864: 2863: 2825: 2822: 2821: 2768: 2765: 2764: 2733: 2730: 2729: 2713: 2710: 2709: 2693: 2690: 2689: 2673: 2670: 2669: 2651: 2573:axiom of choice 2569: 2506: 2503: 2502: 2481: 2477: 2459: 2455: 2447: 2444: 2443: 2413: 2410: 2409: 2407: 2401: 2358: 2354: 2352: 2349: 2348: 2331: 2327: 2298: 2295: 2294: 2243: 2235: 2232: 2231: 2215: 2207: 2204: 2203: 2198:over the field 2184: 2140: 2138: 2135: 2134: 2118: 2116: 2113: 2112: 2111:is linear over 2077: 2074: 2073: 2071: 2059: 2039: 2036: 2035: 2033: 2027: 2004: 2002: 1999: 1998: 1961: 1958: 1957: 1935: 1927: 1924: 1923: 1907: 1904: 1903: 1880: 1846: 1843: 1842: 1825: 1821: 1819: 1816: 1815: 1796: 1793: 1792: 1772: 1769: 1768: 1727: 1723: 1715: 1712: 1711: 1689: 1686: 1685: 1639: 1635: 1620: 1616: 1615: 1613: 1601: 1597: 1589: 1586: 1585: 1563: 1560: 1559: 1530: 1526: 1516: 1514: 1496: 1492: 1490: 1487: 1486: 1470: 1467: 1466: 1437: 1420: 1417: 1416: 1390: 1373: 1349: 1331: 1328: 1327: 1318:of real-valued 1303: 1300: 1299: 1276: 1272: 1264: 1252: 1248: 1237: 1234: 1233: 1217: 1214: 1213: 1196: 1192: 1190: 1187: 1186: 1183: 1111: 1108: 1107: 1091: 1088: 1087: 1047: 1044: 1043: 1012: 1009: 1008: 938: 935: 934: 915: 904: 901: 900: 875: 872: 871: 870:. Thus for any 845: 816: 784: 758: 755: 754: 730: 727: 726: 681: 675: 671: 666: 660: 649: 644: 640: 617: 614: 613: 574: 568: 564: 559: 553: 542: 536: 533: 532: 503: 499: 481: 469: 466: 465: 439: 435: 421: 415: 411: 406: 400: 389: 368: 364: 352: 348: 342: 331: 326: 322: 299: 296: 295: 268: 264: 252: 248: 242: 231: 210: 207: 206: 180: 176: 161: 157: 148: 144: 143: 139: 137: 134: 133: 89: 86: 85: 74: 66:axiom of choice 12: 11: 5: 5004: 4994: 4993: 4988: 4983: 4966: 4965: 4963: 4962: 4951: 4948: 4947: 4945: 4944: 4939: 4934: 4929: 4927:Ultrabarrelled 4919: 4913: 4908: 4902: 4897: 4892: 4887: 4882: 4877: 4868: 4862: 4857: 4855:Quasi-complete 4852: 4850:Quasibarrelled 4847: 4842: 4837: 4832: 4827: 4822: 4817: 4812: 4807: 4802: 4797: 4792: 4791: 4790: 4780: 4775: 4770: 4765: 4760: 4755: 4750: 4745: 4740: 4730: 4725: 4715: 4710: 4705: 4699: 4697: 4693: 4692: 4690: 4689: 4679: 4674: 4669: 4664: 4659: 4649: 4643: 4641: 4640:Set operations 4637: 4636: 4634: 4633: 4628: 4623: 4618: 4613: 4608: 4603: 4595: 4587: 4582: 4577: 4572: 4567: 4562: 4557: 4552: 4547: 4541: 4539: 4535: 4534: 4532: 4531: 4526: 4521: 4516: 4511: 4510: 4509: 4504: 4499: 4489: 4484: 4483: 4482: 4477: 4472: 4467: 4462: 4457: 4452: 4442: 4441: 4440: 4429: 4427: 4423: 4422: 4420: 4419: 4414: 4413: 4412: 4402: 4396: 4387: 4382: 4377: 4375:Banach–Alaoglu 4372: 4370:Anderson–Kadec 4366: 4364: 4358: 4357: 4355: 4354: 4349: 4344: 4339: 4334: 4329: 4324: 4319: 4314: 4309: 4304: 4298: 4296: 4295:Basic concepts 4292: 4291: 4283: 4282: 4275: 4268: 4260: 4251: 4250: 4248: 4247: 4236: 4233: 4232: 4230: 4229: 4224: 4219: 4214: 4212:Choquet theory 4209: 4204: 4198: 4196: 4192: 4191: 4189: 4188: 4178: 4173: 4168: 4163: 4158: 4153: 4148: 4143: 4138: 4133: 4128: 4122: 4120: 4116: 4115: 4113: 4112: 4107: 4101: 4099: 4095: 4094: 4092: 4091: 4086: 4081: 4076: 4071: 4066: 4064:Banach algebra 4060: 4058: 4054: 4053: 4051: 4050: 4045: 4040: 4035: 4030: 4025: 4020: 4015: 4010: 4005: 3999: 3997: 3993: 3992: 3990: 3989: 3987:Banach–Alaoglu 3984: 3979: 3974: 3969: 3964: 3959: 3954: 3949: 3943: 3941: 3935: 3934: 3931: 3930: 3928: 3927: 3922: 3917: 3915:Locally convex 3912: 3898: 3893: 3887: 3885: 3881: 3880: 3878: 3877: 3872: 3867: 3862: 3857: 3852: 3847: 3842: 3837: 3832: 3826: 3820: 3816: 3815: 3799: 3798: 3791: 3784: 3776: 3770: 3769: 3754: 3736: 3735: 3726: 3719: 3699: 3658: 3657: 3655: 3652: 3651: 3650: 3644: 3633: 3630: 3610: 3607: 3604: 3597: 3593: 3590: 3587: 3584: 3580: 3576: 3573: 3567: 3563: 3560: 3557: 3554: 3550: 3541: 3537: 3533: 3530: 3527: 3524: 3493: 3490: 3487: 3484: 3481: 3459: 3455: 3430: 3427: 3424: 3421: 3418: 3415: 3394: 3391: 3388: 3385: 3381: 3377: 3372: 3368: 3341: 3338: 3328: 3325: 3319:). Note that 3304: 3301: 3298: 3295: 3246: 3220: 3191: 3188: 3185: 3182: 3148: 3145: 3132:is called the 3119: 3116: 3090: 3071: 3066: 3063: 3039: 3035: 3032: 3029: 3026: 3003: 3000: 2997: 2994: 2972: 2968: 2965: 2962: 2959: 2929: 2926: 2923: 2920: 2900: 2880: 2877: 2874: 2871: 2844: 2841: 2838: 2835: 2832: 2829: 2805: 2802: 2799: 2796: 2793: 2790: 2787: 2784: 2781: 2778: 2775: 2772: 2752: 2749: 2746: 2743: 2740: 2737: 2717: 2697: 2688:be a map from 2677: 2650: 2647: 2630:constructivism 2618:Baire property 2606:constructivist 2568: 2565: 2528: 2525: 2522: 2519: 2516: 2513: 2510: 2489: 2484: 2480: 2476: 2473: 2470: 2467: 2462: 2458: 2454: 2451: 2423: 2420: 2417: 2403: 2397: 2361: 2357: 2334: 2330: 2326: 2323: 2320: 2317: 2314: 2311: 2308: 2305: 2302: 2250: 2246: 2242: 2239: 2218: 2214: 2211: 2183: 2180: 2143: 2121: 2096: 2093: 2090: 2087: 2084: 2081: 2067: 2055: 2043: 2029: 2023: 2007: 1983: 1980: 1977: 1974: 1971: 1968: 1965: 1945: 1942: 1938: 1934: 1931: 1911: 1890:is known as a 1879: 1876: 1856: 1853: 1850: 1828: 1824: 1800: 1776: 1756: 1753: 1750: 1747: 1744: 1741: 1738: 1735: 1730: 1726: 1722: 1719: 1699: 1696: 1693: 1671: 1668: 1665: 1662: 1657: 1653: 1650: 1647: 1642: 1638: 1634: 1631: 1628: 1623: 1619: 1612: 1609: 1604: 1600: 1596: 1593: 1573: 1570: 1567: 1545: 1541: 1538: 1533: 1529: 1525: 1522: 1519: 1513: 1510: 1507: 1504: 1499: 1495: 1474: 1453: 1450: 1447: 1443: 1440: 1436: 1433: 1430: 1427: 1424: 1415:map, given by 1397: 1393: 1389: 1386: 1383: 1380: 1376: 1370: 1367: 1364: 1361: 1358: 1355: 1352: 1348: 1344: 1341: 1338: 1335: 1307: 1284: 1279: 1275: 1271: 1267: 1263: 1260: 1255: 1251: 1247: 1244: 1241: 1221: 1199: 1195: 1182: 1179: 1124: 1121: 1118: 1115: 1095: 1075: 1072: 1069: 1066: 1063: 1060: 1057: 1054: 1051: 1031: 1028: 1025: 1022: 1019: 1016: 996: 993: 990: 987: 984: 981: 978: 975: 972: 969: 966: 963: 960: 957: 954: 951: 948: 945: 942: 922: 918: 914: 911: 908: 899:we can choose 888: 885: 882: 879: 855: 851: 848: 844: 841: 838: 835: 832: 829: 826: 822: 819: 815: 812: 809: 806: 803: 800: 797: 794: 790: 787: 783: 780: 777: 774: 771: 768: 765: 762: 734: 714: 711: 708: 705: 702: 699: 696: 693: 689: 684: 678: 674: 669: 663: 658: 655: 652: 648: 643: 639: 636: 633: 630: 627: 624: 621: 593: 590: 587: 584: 581: 577: 571: 567: 562: 556: 551: 548: 545: 541: 520: 517: 514: 511: 506: 502: 498: 495: 492: 489: 484: 480: 476: 473: 453: 450: 447: 442: 438: 434: 431: 428: 424: 418: 414: 409: 403: 398: 395: 392: 388: 384: 380: 376: 371: 367: 363: 360: 355: 351: 345: 340: 337: 334: 330: 325: 321: 318: 315: 312: 309: 306: 303: 290:and so by the 279: 276: 271: 267: 263: 260: 255: 251: 245: 240: 237: 234: 230: 226: 223: 220: 217: 214: 189: 183: 179: 175: 172: 169: 164: 160: 156: 151: 147: 142: 105: 102: 99: 96: 93: 73: 70: 9: 6: 4: 3: 2: 5003: 4992: 4989: 4987: 4984: 4982: 4979: 4978: 4976: 4961: 4953: 4952: 4949: 4943: 4940: 4938: 4935: 4933: 4930: 4928: 4924: 4920: 4918:) convex 4917: 4914: 4912: 4909: 4907: 4903: 4901: 4898: 4896: 4893: 4891: 4890:Semi-complete 4888: 4886: 4883: 4881: 4878: 4876: 4872: 4869: 4867: 4863: 4861: 4858: 4856: 4853: 4851: 4848: 4846: 4843: 4841: 4838: 4836: 4833: 4831: 4828: 4826: 4823: 4821: 4818: 4816: 4813: 4811: 4808: 4806: 4805:Infrabarreled 4803: 4801: 4798: 4796: 4793: 4789: 4786: 4785: 4784: 4781: 4779: 4776: 4774: 4771: 4769: 4766: 4764: 4763:Distinguished 4761: 4759: 4756: 4754: 4751: 4749: 4746: 4744: 4741: 4739: 4735: 4731: 4729: 4726: 4724: 4720: 4716: 4714: 4711: 4709: 4706: 4704: 4701: 4700: 4698: 4696:Types of TVSs 4694: 4688: 4684: 4680: 4678: 4675: 4673: 4670: 4668: 4665: 4663: 4660: 4658: 4654: 4650: 4648: 4645: 4644: 4642: 4638: 4632: 4629: 4627: 4624: 4622: 4619: 4617: 4616:Prevalent/Shy 4614: 4612: 4609: 4607: 4606:Extreme point 4604: 4602: 4596: 4594: 4588: 4586: 4583: 4581: 4578: 4576: 4573: 4571: 4568: 4566: 4563: 4561: 4558: 4556: 4553: 4551: 4548: 4546: 4543: 4542: 4540: 4538:Types of sets 4536: 4530: 4527: 4525: 4522: 4520: 4517: 4515: 4512: 4508: 4505: 4503: 4500: 4498: 4495: 4494: 4493: 4490: 4488: 4485: 4481: 4480:Discontinuous 4478: 4476: 4473: 4471: 4468: 4466: 4463: 4461: 4458: 4456: 4453: 4451: 4448: 4447: 4446: 4443: 4439: 4436: 4435: 4434: 4431: 4430: 4428: 4424: 4418: 4415: 4411: 4408: 4407: 4406: 4403: 4400: 4397: 4395: 4391: 4388: 4386: 4383: 4381: 4378: 4376: 4373: 4371: 4368: 4367: 4365: 4363: 4359: 4353: 4350: 4348: 4345: 4343: 4340: 4338: 4337:Metrizability 4335: 4333: 4330: 4328: 4325: 4323: 4322:FrĂ©chet space 4320: 4318: 4315: 4313: 4310: 4308: 4305: 4303: 4300: 4299: 4297: 4293: 4288: 4281: 4276: 4274: 4269: 4267: 4262: 4261: 4258: 4246: 4238: 4237: 4234: 4228: 4225: 4223: 4220: 4218: 4217:Weak topology 4215: 4213: 4210: 4208: 4205: 4203: 4200: 4199: 4197: 4193: 4186: 4182: 4179: 4177: 4174: 4172: 4169: 4167: 4164: 4162: 4159: 4157: 4154: 4152: 4149: 4147: 4144: 4142: 4141:Index theorem 4139: 4137: 4134: 4132: 4129: 4127: 4124: 4123: 4121: 4117: 4111: 4108: 4106: 4103: 4102: 4100: 4098:Open problems 4096: 4090: 4087: 4085: 4082: 4080: 4077: 4075: 4072: 4070: 4067: 4065: 4062: 4061: 4059: 4055: 4049: 4046: 4044: 4041: 4039: 4036: 4034: 4031: 4029: 4026: 4024: 4021: 4019: 4016: 4014: 4011: 4009: 4006: 4004: 4001: 4000: 3998: 3994: 3988: 3985: 3983: 3980: 3978: 3975: 3973: 3970: 3968: 3965: 3963: 3960: 3958: 3955: 3953: 3950: 3948: 3945: 3944: 3942: 3940: 3936: 3926: 3923: 3921: 3918: 3916: 3913: 3910: 3906: 3902: 3899: 3897: 3894: 3892: 3889: 3888: 3886: 3882: 3876: 3873: 3871: 3868: 3866: 3863: 3861: 3858: 3856: 3853: 3851: 3848: 3846: 3843: 3841: 3838: 3836: 3833: 3831: 3828: 3827: 3824: 3821: 3817: 3812: 3808: 3804: 3797: 3792: 3790: 3785: 3783: 3778: 3777: 3774: 3767: 3766:0-12-622760-8 3763: 3759: 3755: 3752: 3751:1-4020-1560-7 3748: 3744: 3740: 3739: 3730: 3722: 3720:9780080532998 3716: 3712: 3711: 3703: 3695: 3691: 3687: 3683: 3679: 3675: 3674: 3669: 3663: 3659: 3648: 3645: 3639: 3636: 3635: 3629: 3627: 3622: 3608: 3605: 3602: 3588: 3582: 3574: 3571: 3558: 3552: 3539: 3535: 3531: 3525: 3514: 3510: 3505: 3491: 3488: 3485: 3482: 3479: 3457: 3453: 3444: 3428: 3425: 3422: 3419: 3416: 3413: 3405: 3389: 3386: 3383: 3370: 3366: 3356: 3352: 3348: 3337: 3334: 3324: 3322: 3318: 3302: 3299: 3296: 3293: 3285: 3281: 3277: 3273: 3269: 3265: 3261: 3235: 3209: 3205: 3189: 3186: 3183: 3180: 3172: 3167: 3165: 3159: 3146: 3143: 3135: 3114: 3104: 3088: 3069: 3061: 3030: 3001: 2998: 2995: 2992: 2963: 2946: 2943: 2927: 2924: 2921: 2918: 2911:is closed in 2898: 2875: 2862:If the graph 2860: 2858: 2842: 2836: 2830: 2827: 2819: 2803: 2800: 2794: 2791: 2785: 2779: 2776: 2773: 2770: 2750: 2744: 2738: 2735: 2715: 2695: 2675: 2666: 2664: 2660: 2656: 2646: 2642: 2639: 2635: 2631: 2627: 2623: 2619: 2615: 2611: 2607: 2602: 2600: 2596: 2592: 2587: 2585: 2582: 2578: 2577:Banach spaces 2574: 2564: 2560: 2558: 2554: 2550: 2546: 2542: 2526: 2523: 2520: 2517: 2514: 2511: 2508: 2482: 2478: 2471: 2468: 2460: 2456: 2449: 2441: 2437: 2421: 2418: 2415: 2406: 2400: 2396: 2392: 2388: 2384: 2379: 2377: 2359: 2355: 2332: 2328: 2321: 2315: 2312: 2306: 2300: 2292: 2288: 2284: 2280: 2276: 2272: 2268: 2264: 2248: 2240: 2237: 2212: 2209: 2201: 2197: 2196:normed spaces 2193: 2189: 2179: 2176: 2174: 2170: 2166: 2162: 2158: 2110: 2094: 2091: 2085: 2079: 2070: 2066: 2062: 2058: 2041: 2032: 2026: 2022: 1996: 1981: 1978: 1975: 1969: 1963: 1943: 1932: 1929: 1909: 1901: 1897: 1893: 1889: 1885: 1875: 1872: 1870: 1854: 1848: 1826: 1822: 1814: 1798: 1790: 1774: 1754: 1751: 1745: 1739: 1728: 1724: 1717: 1691: 1682: 1663: 1660: 1655: 1648: 1645: 1640: 1636: 1629: 1626: 1621: 1617: 1610: 1602: 1598: 1591: 1571: 1568: 1565: 1543: 1536: 1531: 1527: 1520: 1517: 1511: 1505: 1497: 1493: 1472: 1448: 1441: 1438: 1434: 1428: 1422: 1414: 1412: 1395: 1384: 1378: 1365: 1362: 1359: 1353: 1350: 1342: 1336: 1325: 1321: 1305: 1296: 1277: 1273: 1265: 1253: 1249: 1242: 1219: 1197: 1193: 1178: 1176: 1172: 1168: 1164: 1160: 1156: 1152: 1148: 1145: 1141: 1136: 1119: 1113: 1093: 1070: 1067: 1061: 1055: 1049: 1026: 1023: 1020: 1014: 991: 988: 982: 976: 970: 967: 958: 955: 952: 946: 940: 920: 916: 912: 909: 906: 886: 883: 880: 877: 869: 849: 846: 842: 839: 833: 830: 820: 817: 813: 810: 804: 798: 788: 785: 778: 775: 769: 763: 752: 748: 732: 712: 706: 700: 697: 694: 691: 687: 676: 672: 661: 656: 653: 650: 646: 641: 637: 628: 622: 612:, one finds 611: 607: 588: 582: 579: 569: 565: 554: 549: 546: 543: 539: 518: 504: 500: 493: 482: 474: 471: 451: 440: 436: 429: 416: 412: 401: 396: 393: 390: 386: 382: 369: 365: 358: 353: 349: 343: 338: 335: 332: 328: 319: 310: 304: 293: 277: 269: 265: 258: 253: 249: 243: 238: 235: 232: 228: 224: 218: 212: 204: 187: 181: 177: 173: 170: 167: 162: 158: 154: 149: 145: 140: 131: 127: 123: 119: 103: 97: 94: 91: 83: 79: 69: 67: 63: 59: 55: 54:normed spaces 51: 47: 43: 39: 35: 31: 30:linear spaces 27: 23: 19: 4866:Polynomially 4795:Grothendieck 4788:tame FrĂ©chet 4738:Bornological 4598:Linear cone 4590:Convex cone 4565:Banach disks 4507:Sesquilinear 4479: 4362:Main results 4352:Vector space 4307:Completeness 4302:Banach space 4207:Balanced set 4181:Distribution 4119:Applications 3972:Krein–Milman 3957:Closed graph 3757: 3742: 3729: 3709: 3702: 3677: 3671: 3662: 3623: 3506: 3472:spaces with 3406:spaces with 3343: 3330: 3320: 3279: 3275: 3271: 3267: 3263: 3259: 3233: 3203: 3170: 3168: 3163: 3160: 3133: 3102: 2944: 2941: 2861: 2817: 2728:with domain 2667: 2662: 2652: 2643: 2637: 2603: 2593:exhibited a 2588: 2570: 2561: 2556: 2552: 2548: 2547:by defining 2544: 2439: 2404: 2398: 2394: 2386: 2382: 2380: 2375: 2290: 2286: 2282: 2278: 2274: 2270: 2266: 2262: 2261:Assume that 2199: 2191: 2187: 2185: 2177: 2172: 2159:is also not 2156: 2108: 2068: 2064: 2060: 2056: 2030: 2024: 2020: 1994: 1895: 1884:real numbers 1881: 1873: 1683: 1409: 1326:, that is, 1324:uniform norm 1297: 1184: 1174: 1170: 1166: 1162: 1158: 1154: 1150: 1149:exists. If 1146: 1139: 1137: 867: 750: 605: 202: 125: 121: 117: 81: 77: 75: 57: 15: 4860:Quasinormed 4773:FK-AK space 4667:Linear span 4662:Convex hull 4647:Affine hull 4450:Almost open 4390:Hahn–Banach 4136:Heat kernel 4126:Hardy space 4033:Trace class 3947:Hahn–Banach 3909:Topological 2632:, there is 2438:vectors in 2072:) = Ď€, but 2054:. Then lim 1892:Hamel basis 1710:instead of 1465:defined on 1413:-at-a-point 50:dimensional 22:linear maps 18:mathematics 4975:Categories 4900:Stereotype 4758:(DF)-space 4753:Convenient 4492:Functional 4460:Continuous 4445:Linear map 4385:F. Riesz's 4327:Linear map 4069:C*-algebra 3884:Properties 3654:References 3515:given by 3333:dual space 3101:is called 2599:set theory 2584:set theory 2169:Vitali set 2161:measurable 2133:(not over 1813:dual space 1411:derivative 46:continuous 40:(that is, 4916:Uniformly 4875:Reflexive 4723:Barrelled 4719:Countably 4631:Symmetric 4529:Transpose 4043:Unbounded 4038:Transpose 3996:Operators 3925:Separable 3920:Reflexive 3905:Algebraic 3891:Barrelled 3536:∫ 3529:‖ 3523:‖ 3513:quasinorm 3297:× 3210:from to 3184:× 3118:¯ 3065:¯ 3038:¯ 3025:Γ 2996:× 2971:¯ 2958:Γ 2922:× 2870:Γ 2831:⁡ 2798:→ 2792:⊆ 2780:⁡ 2739:⁡ 2527:… 2501:for each 2488:‖ 2475:‖ 2419:≥ 2086:π 2042:π 1970:π 1941:→ 1910:π 1888:rationals 1852:→ 1827:∗ 1737:→ 1698:∞ 1695:→ 1670:∞ 1667:→ 1646:⋅ 1630:⁡ 1569:≥ 1521:⁡ 1354:∈ 1340:‖ 1334:‖ 1283:‖ 1270:‖ 1262:‖ 1240:‖ 1071:ϵ 1027:δ 992:ϵ 968:⊆ 959:δ 913:ϵ 910:≤ 907:δ 878:ϵ 854:‖ 843:− 837:‖ 831:≤ 828:‖ 814:− 802:‖ 796:‖ 776:− 761:‖ 710:‖ 704:‖ 695:≤ 647:∑ 638:≤ 635:‖ 620:‖ 604:for some 592:‖ 586:‖ 580:≤ 540:∑ 513:‖ 491:‖ 464:Letting 449:‖ 427:‖ 387:∑ 383:≤ 329:∑ 317:‖ 302:‖ 229:∑ 171:… 101:→ 26:functions 4960:Category 4911:Strictly 4885:Schwartz 4825:LF-space 4820:LB-space 4778:FK-space 4748:Complete 4728:BK-space 4653:Relative 4600:(subset) 4592:(subset) 4519:Seminorm 4502:Bilinear 4245:Category 4057:Algebras 3939:Theorems 3896:Complete 3865:Schwartz 3811:glossary 3680:: 1–56, 3632:See also 3103:closable 2940:we call 2763:written 2391:sequence 2165:additive 1956:so that 1442:′ 1144:supremum 933:so that 850:′ 821:′ 789:′ 379:‖ 324:‖ 62:complete 4925:)  4873:)  4815:K-space 4800:Hilbert 4783:FrĂ©chet 4768:F-space 4743:Brauner 4736:)  4721:)  4703:Asplund 4685:)  4655:)  4575:Bounded 4470:Compact 4455:Bounded 4392: ( 4048:Unitary 4028:Nuclear 4013:Compact 4008:Bounded 4003:Adjoint 3977:Min–max 3870:Sobolev 3855:Nuclear 3845:Hilbert 3840:FrĂ©chet 3805: ( 3694:0265151 3262:() and 3134:closure 2626:F-space 4937:Webbed 4923:Quasi- 4845:Montel 4835:Mackey 4734:Ultra- 4713:Banach 4621:Radial 4585:Convex 4555:Affine 4497:Linear 4465:Closed 4289:(TVSs) 4023:Normal 3860:Orlicz 3850:Hölder 3830:Banach 3819:Spaces 3807:topics 3764:  3749:  3717:  3692:  3626:groups 3105:, and 2945:closed 2655:closed 2347:where 2202:where 1869:closed 725:Thus, 4895:Smith 4880:Riesz 4871:Semi- 4683:Quasi 4677:Polar 3835:Besov 2638:every 2595:model 2434:) of 2285:from 2273:from 2163:; an 745:is a 124:. If 4514:Norm 4438:form 4426:Maps 4183:(or 3901:Dual 3762:ISBN 3747:ISBN 3715:ISBN 3489:< 3483:< 3423:< 3417:< 3331:The 3232:and 2190:and 1558:for 1408:The 1157:and 1106:and 1042:and 881:> 80:and 76:Let 3682:doi 3173:of 3171:all 3136:of 3014:If 2985:in 2891:of 2828:Dom 2777:Dom 2736:Dom 2708:to 2597:of 2581:ZFC 2543:of 2381:If 2289:to 2277:to 2230:or 2194:be 1896:any 1791:on 1684:as 1627:cos 1518:sin 1347:sup 1173:to 1138:If 479:sup 294:, 201:in 128:is 120:to 16:In 4977:: 3809:– 3690:MR 3688:, 3678:92 3274:↦ 2614:BP 2612:+ 2610:DC 2378:. 2095:0. 1871:. 1177:. 20:, 4921:( 4906:B 4904:( 4864:( 4732:( 4717:( 4681:( 4651:( 4401:) 4279:e 4272:t 4265:v 4187:) 3911:) 3907:/ 3903:( 3813:) 3795:e 3788:t 3781:v 3768:. 3753:. 3724:. 3697:. 3684:: 3609:. 3606:x 3603:d 3596:| 3592:) 3589:x 3586:( 3583:f 3579:| 3575:+ 3572:1 3566:| 3562:) 3559:x 3556:( 3553:f 3549:| 3540:I 3532:= 3526:f 3492:1 3486:p 3480:0 3458:p 3454:L 3429:, 3426:1 3420:p 3414:0 3393:) 3390:x 3387:d 3384:, 3380:R 3376:( 3371:p 3367:L 3321:X 3303:, 3300:Y 3294:X 3280:x 3278:( 3276:p 3272:x 3268:T 3264:C 3260:C 3245:R 3234:Y 3219:R 3204:X 3190:. 3187:Y 3181:X 3164:X 3147:. 3144:T 3115:T 3089:T 3070:, 3062:T 3034:) 3031:T 3028:( 3002:. 2999:Y 2993:X 2967:) 2964:T 2961:( 2942:T 2928:, 2925:Y 2919:X 2899:T 2879:) 2876:T 2873:( 2843:. 2840:) 2837:T 2834:( 2818:X 2804:. 2801:Y 2795:X 2789:) 2786:T 2783:( 2774:: 2771:T 2751:, 2748:) 2745:T 2742:( 2716:Y 2696:X 2676:T 2557:X 2553:T 2549:T 2545:X 2524:, 2521:2 2518:, 2515:1 2512:= 2509:n 2483:n 2479:e 2472:n 2469:= 2466:) 2461:n 2457:e 2453:( 2450:T 2440:X 2422:1 2416:n 2408:( 2405:n 2402:) 2399:n 2395:e 2393:( 2387:f 2383:X 2376:Y 2360:0 2356:y 2333:0 2329:y 2325:) 2322:x 2319:( 2316:f 2313:= 2310:) 2307:x 2304:( 2301:g 2291:Y 2287:X 2283:g 2279:K 2275:X 2271:f 2267:Y 2263:X 2249:. 2245:C 2241:= 2238:K 2217:R 2213:= 2210:K 2200:K 2192:Y 2188:X 2173:f 2157:f 2142:R 2120:Q 2109:f 2092:= 2089:) 2083:( 2080:f 2069:n 2065:r 2063:( 2061:f 2057:n 2031:n 2028:} 2025:n 2021:r 2006:R 1995:f 1982:, 1979:0 1976:= 1973:) 1967:( 1964:f 1944:R 1937:R 1933:: 1930:f 1855:X 1849:X 1823:X 1799:X 1775:T 1755:0 1752:= 1749:) 1746:0 1743:( 1740:T 1734:) 1729:n 1725:f 1721:( 1718:T 1692:n 1664:n 1661:= 1656:n 1652:) 1649:0 1641:2 1637:n 1633:( 1622:2 1618:n 1611:= 1608:) 1603:n 1599:f 1595:( 1592:T 1572:1 1566:n 1544:n 1540:) 1537:x 1532:2 1528:n 1524:( 1512:= 1509:) 1506:x 1503:( 1498:n 1494:f 1473:X 1452:) 1449:0 1446:( 1439:f 1435:= 1432:) 1429:f 1426:( 1423:T 1396:. 1392:| 1388:) 1385:x 1382:( 1379:f 1375:| 1369:] 1366:1 1363:, 1360:0 1357:[ 1351:x 1343:= 1337:f 1306:X 1278:i 1274:e 1266:/ 1259:) 1254:i 1250:e 1246:( 1243:T 1220:T 1198:i 1194:e 1175:Y 1171:X 1167:Y 1163:X 1159:Y 1155:X 1151:Y 1147:M 1140:X 1123:) 1120:x 1117:( 1114:f 1094:x 1074:) 1068:, 1065:) 1062:x 1059:( 1056:f 1053:( 1050:B 1030:) 1024:, 1021:x 1018:( 1015:B 1007:( 995:) 989:, 986:) 983:x 980:( 977:f 974:( 971:B 965:) 962:) 956:, 953:x 950:( 947:B 944:( 941:f 921:K 917:/ 887:, 884:0 868:K 847:x 840:x 834:K 825:) 818:x 811:x 808:( 805:f 799:= 793:) 786:x 782:( 779:f 773:) 770:x 767:( 764:f 751:f 733:f 713:. 707:x 701:M 698:C 692:M 688:) 683:| 677:i 673:x 668:| 662:n 657:1 654:= 651:i 642:( 632:) 629:x 626:( 623:f 606:C 589:x 583:C 576:| 570:i 566:x 561:| 555:n 550:1 547:= 544:i 519:, 516:} 510:) 505:i 501:e 497:( 494:f 488:{ 483:i 475:= 472:M 452:. 446:) 441:i 437:e 433:( 430:f 423:| 417:i 413:x 408:| 402:n 397:1 394:= 391:i 375:) 370:i 366:e 362:( 359:f 354:i 350:x 344:n 339:1 336:= 333:i 320:= 314:) 311:x 308:( 305:f 278:, 275:) 270:i 266:e 262:( 259:f 254:i 250:x 244:n 239:1 236:= 233:i 225:= 222:) 219:x 216:( 213:f 203:X 188:) 182:n 178:e 174:, 168:, 163:2 159:e 155:, 150:1 146:e 141:( 126:X 122:Y 118:X 104:Y 98:X 95:: 92:f 82:Y 78:X

Index

mathematics
linear maps
functions
linear spaces
linear approximation
topological spaces
topological vector spaces
continuous
dimensional
normed spaces
complete
axiom of choice
finite-dimensional
triangle inequality
any two norms on a finite-dimensional space are equivalent
bounded linear operator
supremum
smooth functions
uniform norm
derivative
linear functional
dual space
closed
real numbers
rationals
Hamel basis
noncommensurable
measurable
additive
Vitali set

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