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Sigma-additive set function

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One can check that this function is additive by using the linearity of the limit. That this function is not σ-additive follows by considering the sequence of disjoint sets
1323: 3516: 3648: 2807: 2199: 741: 2055: 3604: 3309: 3304: 3215: 2763: 1939: 1818: 1243: 940: 3728: 3551: 3418: 2146: 1617: 715: 692: 2172: 1574: 1269: 3442: 1436: 3692: 3672: 3279: 2902: 2028: 1913: 1885: 1792: 1594: 1554: 1488: 1456: 1416: 1200: 512: 420: 259: 3235: 2339: 2118: 2096: 1644: 2316: 568: 548: 150: 488: 42: 381:) of a set sum when considering multiple objects. Additivity is a weaker condition than σ-additivity; that is, σ-additivity implies additivity. 3075:
is a sequence of disjoint sets of real numbers, then either none of the sets contains 0, or precisely one of them does. In either case, the equality
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If this additivity property holds for any two sets, then it also holds for any finite number of sets, namely, the function value on the union of
2547: 2630: 89: 61: 3882: 606: 108: 1281: 68: 2343: 3763: 244:(the terms are equivalent). However, a finitely additive set function might not have the additivity property for a union of an 75: 46: 2812: 57: 3781: 3013: 985: 3917: 2491: 2435: 3558: 2002: 1050: 577: 952: 491: 432: 163: 3814: 2719: 1731: 859: 3912: 3808: 2713: 35: 1501: 3001:{\displaystyle \mu (A)={\begin{cases}1&{\mbox{ if }}0\in A\\0&{\mbox{ if }}0\notin A.\end{cases}}} 1944: 1823: 747: 130: 3451: 82: 3790: 3183: 1459: 366: 3492: 3609: 2768: 2177: 2067: 1996: 720: 2939: 2727:
Note that modularity has a different and unrelated meaning in the context of complex functions; see
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where all sets in the union are disjoint. Additivity implies that both sides of the equality equal
3287: 3200: 2742: 1918: 1797: 3837: 3697: 1221: 918: 253: 153: 3521: 1175:{\displaystyle \mu \left(\bigcup _{n=1}^{\infty }A_{n}\right)=\sum _{n=1}^{\infty }\mu (A_{n}),} 3172:{\displaystyle \mu \left(\bigcup _{n=1}^{\infty }A_{n}\right)=\sum _{n=1}^{\infty }\mu (A_{n})} 3888: 3878: 3403: 2122: 1599: 1246: 849:{\displaystyle \mu \left(\bigcup _{n=1}^{N}A_{n}\right)=\sum _{n=1}^{N}\mu \left(A_{n}\right)} 697: 674: 2151: 1559: 356:{\textstyle \mu \left(\bigcup _{n=1}^{\infty }A_{n}\right)=\sum _{n=1}^{\infty }\mu (A_{n}).} 3755: 3421: 1251: 3427: 3261:
An example of an additive function which is not σ-additive is obtained by considering
1421: 1391:{\displaystyle \mu \left(\bigcup {\mathcal {G}}\right)=\sup _{G\in {\mathcal {G}}}\mu (G),} 3677: 3657: 3264: 2887: 2013: 1898: 1870: 1777: 1579: 1539: 1473: 1441: 1401: 1185: 497: 405: 3819: 3220: 2321: 2100: 2078: 1626: 3802: 3759: 3651: 3187: 2301: 2031: 553: 533: 3393:{\displaystyle \mu (A)=\lim _{k\to \infty }{\frac {1}{k}}\cdot \lambda (A\cap (0,k)),} 458: 135: 3906: 976: 427: 236:
is a finite number) equals the sum of its values on the sets. Therefore, an additive
3775: 3747: 3445: 2728: 2008: 1272: 571: 423: 237: 157: 3282: 2909: 122: 24: 3833: 1210:. Every 𝜎-additive function is additive but not vice versa, as shown below. 3892: 2905: 1721:{\displaystyle \mu (A)=\mu (A\cup \varnothing )=\mu (A)+\mu (\varnothing ).} 3872: 3824: 3238: 1276: 980: 365:
Additivity and sigma-additivity are particularly important properties of
2620:{\displaystyle A\cup B=(A\cap B)\cup (A\setminus B)\cup (B\setminus A),} 3739: 2703:{\displaystyle \mu (A\setminus B)+\mu (B\setminus A)+2\mu (A\cap B).} 378: 370: 1766:
then this equality can be satisfied only by plus or minus infinity.
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A consequence of this is that an additive function cannot take both
3750:). For sigma-additivity, one needs in addition that the concept of 2295:
and the argument below proves that additivity implies modularity.
374: 2280:{\displaystyle \phi (A\cup B)+\phi (A\cap B)=\phi (A)+\phi (B)} 152:
mapping sets to numbers, with the property that its value on a
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One may define additive functions with values in any additive
1314:{\textstyle {\mathcal {G}}\subseteq {\mathcal {A}}\cap \tau ,} 18: 3694:
applied to any of the individual sets is zero, so the sum of
369:. They are abstractions of how intuitive properties of size ( 3197:
is defined to be a finitely additive set function that maps
2422:{\displaystyle \mu (A\cup B)+\mu (A\cap B)=\mu (A)+\mu (B).} 2183: 2042: 1366: 1340: 1297: 1287: 1227: 1057: 959: 924: 584: 439: 2994: 1462:(with respect to compact sets) then it is τ-additive. 160:
sets equals the sum of its values on these sets, namely,
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Theory of charges: a study of finitely additive measures
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is a function that has the additivity property even for
3793: – Generalization of mass, length, area and volume 3786:
Pages displaying short descriptions of redirect targets
3762:. Another example, also from quantum mechanics, is the 2973: 2948: 1284: 1224: 1054: 956: 921: 581: 436: 262: 166: 138: 3827:– The set of bounded charges on a given sigma-algebra 3700: 3680: 3660: 3612: 3561: 3524: 3495: 3454: 3430: 3406: 3312: 3290: 3267: 3223: 3203: 3081: 3016: 2918: 2890: 2884:
An example of a 𝜎-additive function is the function
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This article incorporates material from additive on
3805: – Generalized notion of measure in mathematics 2870:{\displaystyle \mu (B\setminus A)=\mu (B)-\mu (A).} 49:. Unsourced material may be challenged and removed. 3784: – Theorem extending pre-measures to measures 3722: 3686: 3666: 3642: 3598: 3545: 3510: 3481: 3436: 3412: 3392: 3298: 3273: 3229: 3209: 3171: 3067: 3000: 2896: 2869: 2801: 2757: 2702: 2619: 2536: 2480: 2421: 2333: 2310: 2279: 2193: 2166: 2140: 2112: 2090: 2049: 2022: 1980: 1933: 1907: 1879: 1859: 1812: 1786: 1758: 1720: 1638: 1611: 1588: 1568: 1548: 1528: 1482: 1450: 1430: 1410: 1390: 1313: 1263: 1237: 1194: 1174: 1068: 1039: 967: 934: 907: 848: 735: 709: 686: 663: 595: 562: 542: 506: 482: 447: 414: 355: 220: 144: 3871:Bhaskara Rao, K. P. S.; Bhaskara Rao, M. (1983). 3257:An additive function which is not σ-additive 3068:{\displaystyle A_{1},A_{2},\ldots ,A_{n},\ldots } 1040:{\displaystyle A_{1},A_{2},\ldots ,A_{n},\ldots } 3838:Creative Commons Attribution/Share-Alike License 3811: – Set-to-real map with diminishing returns 3496: 3431: 3329: 1354: 3730:is also zero, which proves the counterexample. 3758:are sigma-additive functions with values in a 2537:{\displaystyle B=(A\cap B)\cup (B\setminus A)} 2481:{\displaystyle A=(A\cap B)\cup (A\setminus B)} 1470:Useful properties of an additive set function 664:{\displaystyle \mu (A\cup B)=\mu (A)+\mu (B).} 398:Additive (or finitely additive) set functions 8: 3190:for more examples of 𝜎-additive functions. 1218:Suppose that in addition to a sigma algebra 1069:{\displaystyle \scriptstyle {\mathcal {A}},} 596:{\displaystyle \scriptstyle {\mathcal {A}},} 390:is equivalent to additive set function; see 968:{\displaystyle \scriptstyle {\mathcal {A}}} 448:{\displaystyle \scriptstyle {\mathcal {A}}} 221:{\textstyle \mu (A\cup B)=\mu (A)+\mu (B).} 3711: 3699: 3679: 3659: 3611: 3566: 3560: 3523: 3494: 3453: 3429: 3405: 3344: 3332: 3311: 3292: 3291: 3289: 3266: 3249:to mean its range is a bounded subset of 3222: 3202: 3160: 3144: 3133: 3115: 3105: 3094: 3080: 3053: 3034: 3021: 3015: 2972: 2947: 2934: 2917: 2889: 2814: 2770: 2744: 2632: 2549: 2493: 2437: 2345: 2323: 2303: 2206: 2182: 2181: 2179: 2153: 2124: 2102: 2080: 2041: 2040: 2038: 2015: 1946: 1920: 1900: 1872: 1825: 1799: 1779: 1759:{\displaystyle \mu (\varnothing )\neq 0,} 1733: 1650: 1628: 1601: 1581: 1561: 1541: 1503: 1475: 1443: 1423: 1403: 1365: 1364: 1357: 1339: 1338: 1325: 1296: 1295: 1286: 1285: 1283: 1253: 1226: 1225: 1223: 1187: 1160: 1144: 1133: 1115: 1105: 1094: 1080: 1056: 1055: 1052: 1025: 1006: 993: 987: 958: 957: 954: 923: 922: 920: 908:{\displaystyle A_{1},A_{2},\ldots ,A_{N}} 899: 880: 867: 861: 836: 819: 808: 790: 780: 769: 755: 722: 699: 676: 608: 583: 582: 579: 555: 535: 499: 460: 438: 437: 434: 407: 386: 341: 325: 314: 296: 286: 275: 261: 165: 137: 109:Learn how and when to remove this message 3674:applied to the union is then one, while 3281:, defined over the Lebesgue sets of the 1623:: additivity implies that for every set 3850: 3204: 2825: 2664: 2643: 2605: 2587: 2525: 2469: 1741: 1709: 1679: 1511: 3877:. London: Academic Press. p. 35. 3754:be defined on that set. For example, 1529:{\displaystyle \mu (\varnothing )=0,} 7: 1981:{\displaystyle \mu (A)\geq \mu (B).} 1860:{\displaystyle \mu (A)\leq \mu (B).} 750:that an additive function satisfies 47:adding citations to reliable sources 3482:{\displaystyle 0\leq \mu (A)\leq 1} 2712:However, the related properties of 3505: 3339: 3245:charges, where we say a charge is 3145: 3106: 2724:are not equivalent to each other. 1606: 1563: 1145: 1106: 730: 724: 704: 681: 474: 468: 326: 287: 14: 3799: – Concept in measure theory 3511:{\displaystyle \sup A<\infty } 3764:positive operator-valued measure 23: 3650:The union of these sets is the 3643:{\displaystyle n=0,1,2,\ldots } 2802:{\displaystyle \mu (B)-\mu (A)} 2194:{\displaystyle {\mathcal {S}},} 736:{\displaystyle \infty -\infty } 391: 34:needs additional citations for 3836:, which is licensed under the 3717: 3704: 3593: 3575: 3534: 3528: 3470: 3464: 3384: 3381: 3369: 3360: 3336: 3322: 3316: 3166: 3153: 2928: 2922: 2861: 2855: 2846: 2840: 2831: 2819: 2796: 2790: 2781: 2775: 2694: 2682: 2670: 2658: 2649: 2637: 2611: 2599: 2593: 2581: 2575: 2563: 2531: 2519: 2513: 2501: 2475: 2463: 2457: 2445: 2413: 2407: 2398: 2392: 2383: 2371: 2362: 2350: 2274: 2268: 2259: 2253: 2244: 2232: 2223: 2211: 2050:{\displaystyle {\mathcal {S}}} 1972: 1966: 1957: 1951: 1851: 1845: 1836: 1830: 1744: 1738: 1712: 1706: 1697: 1691: 1682: 1670: 1661: 1655: 1576:to all sets in its domain, or 1514: 1508: 1382: 1376: 1166: 1153: 717:as values, for the expression 655: 649: 640: 634: 625: 613: 477: 462: 347: 334: 242:finitely additive set function 212: 206: 197: 191: 182: 170: 1: 3778: – Z-module homomorphism 3599:{\displaystyle A_{n}=[n,n+1)} 2287:The above property is called 1438:-additive. In particular, if 1214:τ-additive set functions 1047:of pairwise disjoint sets in 945:σ-additive set functions 58:"Sigma-additive set function" 3299:{\displaystyle \mathbb {R} } 3210:{\displaystyle \varnothing } 2758:{\displaystyle A\subseteq B} 1934:{\displaystyle A\subseteq B} 1813:{\displaystyle A\subseteq B} 1238:{\textstyle {\mathcal {A}},} 935:{\textstyle {\mathcal {A}}.} 250:σ-additive set function 3723:{\displaystyle \mu (A_{n})} 1619:to all sets in its domain. 3934: 3546:{\displaystyle \mu (A)=0.} 2003:Valuation (measure theory) 2000: 1994: 492:extended real number line 3859:Measure Theory, Volume 4 3815:Subadditive set function 3413:{\displaystyle \lambda } 2141:{\displaystyle A\cup B,} 1612:{\displaystyle -\infty } 710:{\displaystyle +\infty } 687:{\displaystyle -\infty } 3861:, Torres Fremlin, 2003. 3809:Submodular set function 3782:Hahn–Kolmogorov theorem 2167:{\displaystyle A\cap B} 1569:{\displaystyle \infty } 1490:include the following. 3724: 3688: 3668: 3644: 3600: 3547: 3512: 3483: 3438: 3414: 3394: 3300: 3275: 3241:for information about 3231: 3211: 3173: 3149: 3110: 3069: 3002: 2898: 2871: 2803: 2759: 2704: 2621: 2538: 2482: 2423: 2335: 2312: 2281: 2195: 2168: 2142: 2114: 2092: 2051: 2024: 1982: 1935: 1909: 1881: 1861: 1814: 1788: 1760: 1722: 1640: 1613: 1590: 1570: 1550: 1530: 1484: 1452: 1432: 1412: 1392: 1315: 1265: 1264:{\displaystyle \tau .} 1239: 1196: 1176: 1149: 1110: 1070: 1041: 969: 936: 909: 850: 824: 785: 748:mathematical induction 737: 711: 688: 665: 597: 564: 544: 508: 484: 449: 416: 357: 330: 291: 222: 146: 3791:Measure (mathematics) 3725: 3689: 3669: 3645: 3601: 3548: 3513: 3484: 3439: 3437:{\displaystyle \lim } 3415: 3395: 3301: 3276: 3232: 3212: 3174: 3129: 3090: 3070: 3003: 2899: 2872: 2804: 2760: 2705: 2622: 2539: 2483: 2424: 2336: 2313: 2282: 2196: 2169: 2143: 2115: 2093: 2052: 2025: 1983: 1936: 1910: 1891:monotone set function 1882: 1862: 1815: 1789: 1761: 1723: 1641: 1614: 1591: 1571: 1551: 1531: 1485: 1453: 1433: 1431:{\displaystyle \tau } 1413: 1393: 1316: 1275:family of measurable 1266: 1240: 1197: 1177: 1129: 1090: 1071: 1042: 970: 937: 910: 851: 804: 765: 738: 712: 689: 666: 598: 565: 545: 509: 485: 450: 417: 358: 310: 271: 232:disjoint sets (where 223: 147: 127:additive set function 3698: 3687:{\displaystyle \mu } 3678: 3667:{\displaystyle \mu } 3658: 3610: 3559: 3522: 3493: 3452: 3428: 3404: 3310: 3288: 3274:{\displaystyle \mu } 3265: 3221: 3201: 3079: 3014: 2916: 2897:{\displaystyle \mu } 2888: 2813: 2769: 2743: 2631: 2548: 2492: 2436: 2344: 2322: 2302: 2205: 2178: 2152: 2123: 2101: 2079: 2061:modular set function 2037: 2023:{\displaystyle \mu } 2014: 1997:Valuation (geometry) 1945: 1919: 1915:is non-positive and 1908:{\displaystyle \mu } 1899: 1880:{\displaystyle \mu } 1871: 1824: 1798: 1794:is non-negative and 1787:{\displaystyle \mu } 1778: 1732: 1649: 1627: 1600: 1589:{\displaystyle \mu } 1580: 1560: 1549:{\displaystyle \mu } 1540: 1502: 1483:{\displaystyle \mu } 1474: 1451:{\displaystyle \mu } 1442: 1422: 1411:{\displaystyle \mu } 1402: 1324: 1282: 1252: 1222: 1195:{\displaystyle \mu } 1186: 1079: 1051: 986: 953: 919: 860: 754: 721: 698: 675: 607: 578: 554: 534: 507:{\displaystyle \mu } 498: 459: 433: 415:{\displaystyle \mu } 406: 387:modular set function 260: 256:many sets, that is, 164: 136: 43:improve this article 3752:limit of a sequence 3746:or more commonly a 3918:Additive functions 3720: 3684: 3664: 3640: 3596: 3543: 3508: 3479: 3434: 3410: 3390: 3343: 3296: 3271: 3230:{\displaystyle 0.} 3227: 3207: 3169: 3065: 2998: 2993: 2977: 2952: 2894: 2867: 2799: 2755: 2700: 2617: 2534: 2478: 2419: 2334:{\displaystyle B,} 2331: 2308: 2277: 2191: 2164: 2138: 2113:{\displaystyle B,} 2110: 2091:{\displaystyle A,} 2088: 2047: 2020: 1978: 1931: 1905: 1877: 1857: 1810: 1784: 1756: 1718: 1639:{\displaystyle A,} 1636: 1609: 1586: 1566: 1546: 1526: 1494:Value of empty set 1480: 1448: 1428: 1408: 1388: 1372: 1311: 1261: 1235: 1204:countably additive 1192: 1172: 1066: 1065: 1037: 965: 964: 932: 905: 846: 733: 707: 684: 661: 593: 592: 560: 540: 504: 480: 445: 444: 412: 353: 254:countably infinite 248:number of sets. A 218: 142: 3756:spectral measures 3742:(for example any 3352: 3328: 2976: 2951: 2904:defined over the 2809:is defined, then 2311:{\displaystyle A} 1353: 915:disjoint sets in 746:One can prove by 563:{\displaystyle B} 543:{\displaystyle A} 526:finitely additive 240:is also called a 145:{\textstyle \mu } 119: 118: 111: 93: 3925: 3897: 3896: 3868: 3862: 3855: 3797:σ-finite measure 3787: 3729: 3727: 3726: 3721: 3716: 3715: 3693: 3691: 3690: 3685: 3673: 3671: 3670: 3665: 3649: 3647: 3646: 3641: 3605: 3603: 3602: 3597: 3571: 3570: 3552: 3550: 3549: 3544: 3517: 3515: 3514: 3509: 3488: 3486: 3485: 3480: 3443: 3441: 3440: 3435: 3422:Lebesgue measure 3419: 3417: 3416: 3411: 3399: 3397: 3396: 3391: 3353: 3345: 3342: 3305: 3303: 3302: 3297: 3295: 3280: 3278: 3277: 3272: 3236: 3234: 3233: 3228: 3216: 3214: 3213: 3208: 3178: 3176: 3175: 3170: 3165: 3164: 3148: 3143: 3125: 3121: 3120: 3119: 3109: 3104: 3074: 3072: 3071: 3066: 3058: 3057: 3039: 3038: 3026: 3025: 3007: 3005: 3004: 2999: 2997: 2996: 2978: 2974: 2953: 2949: 2903: 2901: 2900: 2895: 2876: 2874: 2873: 2868: 2808: 2806: 2805: 2800: 2764: 2762: 2761: 2756: 2709: 2707: 2706: 2701: 2626: 2624: 2623: 2618: 2543: 2541: 2540: 2535: 2487: 2485: 2484: 2479: 2428: 2426: 2425: 2420: 2340: 2338: 2337: 2332: 2317: 2315: 2314: 2309: 2293: 2292: 2286: 2284: 2283: 2278: 2200: 2198: 2197: 2192: 2187: 2186: 2174:are elements of 2173: 2171: 2170: 2165: 2147: 2145: 2144: 2139: 2119: 2117: 2116: 2111: 2097: 2095: 2094: 2089: 2072: 2071: 2063: 2062: 2056: 2054: 2053: 2048: 2046: 2045: 2029: 2027: 2026: 2021: 1987: 1985: 1984: 1979: 1940: 1938: 1937: 1932: 1914: 1912: 1911: 1906: 1895:. Similarly, If 1893: 1892: 1886: 1884: 1883: 1878: 1866: 1864: 1863: 1858: 1819: 1817: 1816: 1811: 1793: 1791: 1790: 1785: 1765: 1763: 1762: 1757: 1727: 1725: 1724: 1719: 1645: 1643: 1642: 1637: 1618: 1616: 1615: 1610: 1595: 1593: 1592: 1587: 1575: 1573: 1572: 1567: 1555: 1553: 1552: 1547: 1535: 1533: 1532: 1527: 1489: 1487: 1486: 1481: 1457: 1455: 1454: 1449: 1437: 1435: 1434: 1429: 1417: 1415: 1414: 1409: 1397: 1395: 1394: 1389: 1371: 1370: 1369: 1349: 1345: 1344: 1343: 1320: 1318: 1317: 1312: 1301: 1300: 1291: 1290: 1270: 1268: 1267: 1262: 1244: 1242: 1241: 1236: 1231: 1230: 1201: 1199: 1198: 1193: 1181: 1179: 1178: 1173: 1165: 1164: 1148: 1143: 1125: 1121: 1120: 1119: 1109: 1104: 1075: 1073: 1072: 1067: 1061: 1060: 1046: 1044: 1043: 1038: 1030: 1029: 1011: 1010: 998: 997: 974: 972: 971: 966: 963: 962: 941: 939: 938: 933: 928: 927: 914: 912: 911: 906: 904: 903: 885: 884: 872: 871: 855: 853: 852: 847: 845: 841: 840: 823: 818: 800: 796: 795: 794: 784: 779: 742: 740: 739: 734: 716: 714: 713: 708: 693: 691: 690: 685: 670: 668: 667: 662: 602: 600: 599: 594: 588: 587: 569: 567: 566: 561: 549: 547: 546: 541: 528: 527: 520: 519: 513: 511: 510: 505: 494:). The function 489: 487: 486: 483:{\displaystyle } 481: 454: 452: 451: 446: 443: 442: 421: 419: 418: 413: 362: 360: 359: 354: 346: 345: 329: 324: 306: 302: 301: 300: 290: 285: 227: 225: 224: 219: 151: 149: 148: 143: 114: 107: 103: 100: 94: 92: 51: 27: 19: 16:Mapping function 3933: 3932: 3928: 3927: 3926: 3924: 3923: 3922: 3903: 3902: 3901: 3900: 3885: 3870: 3869: 3865: 3856: 3852: 3847: 3785: 3772: 3736: 3734:Generalizations 3707: 3696: 3695: 3676: 3675: 3656: 3655: 3608: 3607: 3562: 3557: 3556: 3520: 3519: 3491: 3490: 3450: 3449: 3448:. It satisfies 3426: 3425: 3402: 3401: 3308: 3307: 3306:by the formula 3286: 3285: 3263: 3262: 3259: 3219: 3218: 3199: 3198: 3156: 3111: 3089: 3085: 3077: 3076: 3049: 3030: 3017: 3012: 3011: 2992: 2991: 2970: 2964: 2963: 2945: 2935: 2914: 2913: 2886: 2885: 2882: 2811: 2810: 2767: 2766: 2741: 2740: 2737: 2629: 2628: 2546: 2545: 2490: 2489: 2434: 2433: 2342: 2341: 2320: 2319: 2300: 2299: 2290: 2289: 2203: 2202: 2176: 2175: 2150: 2149: 2121: 2120: 2099: 2098: 2077: 2076: 2069: 2068: 2060: 2059: 2035: 2034: 2012: 2011: 2005: 1999: 1993: 1943: 1942: 1917: 1916: 1897: 1896: 1890: 1889: 1869: 1868: 1822: 1821: 1796: 1795: 1776: 1775: 1772: 1730: 1729: 1647: 1646: 1625: 1624: 1598: 1597: 1578: 1577: 1558: 1557: 1538: 1537: 1500: 1499: 1496: 1472: 1471: 1468: 1440: 1439: 1420: 1419: 1400: 1399: 1334: 1330: 1322: 1321: 1280: 1279: 1250: 1249: 1220: 1219: 1216: 1184: 1183: 1156: 1111: 1089: 1085: 1077: 1076: 1049: 1048: 1021: 1002: 989: 984: 983: 979:. If for every 951: 950: 947: 917: 916: 895: 876: 863: 858: 857: 832: 828: 786: 764: 760: 752: 751: 719: 718: 696: 695: 673: 672: 605: 604: 576: 575: 552: 551: 532: 531: 525: 524: 517: 516: 496: 495: 457: 456: 455:with values in 431: 430: 428:algebra of sets 404: 403: 400: 337: 292: 270: 266: 258: 257: 162: 161: 134: 133: 115: 104: 98: 95: 52: 50: 40: 28: 17: 12: 11: 5: 3931: 3929: 3921: 3920: 3915: 3913:Measure theory 3905: 3904: 3899: 3898: 3883: 3863: 3857:D. H. Fremlin 3849: 3848: 3846: 3843: 3829: 3828: 3822: 3817: 3812: 3806: 3803:Signed measure 3800: 3794: 3788: 3779: 3771: 3768: 3760:Banach algebra 3735: 3732: 3719: 3714: 3710: 3706: 3703: 3683: 3663: 3652:positive reals 3639: 3636: 3633: 3630: 3627: 3624: 3621: 3618: 3615: 3595: 3592: 3589: 3586: 3583: 3580: 3577: 3574: 3569: 3565: 3542: 3539: 3536: 3533: 3530: 3527: 3507: 3504: 3501: 3498: 3478: 3475: 3472: 3469: 3466: 3463: 3460: 3457: 3433: 3409: 3389: 3386: 3383: 3380: 3377: 3374: 3371: 3368: 3365: 3362: 3359: 3356: 3351: 3348: 3341: 3338: 3335: 3331: 3327: 3324: 3321: 3318: 3315: 3294: 3270: 3258: 3255: 3226: 3206: 3188:signed measure 3168: 3163: 3159: 3155: 3152: 3147: 3142: 3139: 3136: 3132: 3128: 3124: 3118: 3114: 3108: 3103: 3100: 3097: 3093: 3088: 3084: 3064: 3061: 3056: 3052: 3048: 3045: 3042: 3037: 3033: 3029: 3024: 3020: 2995: 2990: 2987: 2984: 2981: 2975: if  2971: 2969: 2966: 2965: 2962: 2959: 2956: 2950: if  2946: 2944: 2941: 2940: 2938: 2933: 2930: 2927: 2924: 2921: 2893: 2881: 2878: 2866: 2863: 2860: 2857: 2854: 2851: 2848: 2845: 2842: 2839: 2836: 2833: 2830: 2827: 2824: 2821: 2818: 2798: 2795: 2792: 2789: 2786: 2783: 2780: 2777: 2774: 2754: 2751: 2748: 2736: 2735:Set difference 2733: 2699: 2696: 2693: 2690: 2687: 2684: 2681: 2678: 2675: 2672: 2669: 2666: 2663: 2660: 2657: 2654: 2651: 2648: 2645: 2642: 2639: 2636: 2616: 2613: 2610: 2607: 2604: 2601: 2598: 2595: 2592: 2589: 2586: 2583: 2580: 2577: 2574: 2571: 2568: 2565: 2562: 2559: 2556: 2553: 2533: 2530: 2527: 2524: 2521: 2518: 2515: 2512: 2509: 2506: 2503: 2500: 2497: 2477: 2474: 2471: 2468: 2465: 2462: 2459: 2456: 2453: 2450: 2447: 2444: 2441: 2418: 2415: 2412: 2409: 2406: 2403: 2400: 2397: 2394: 2391: 2388: 2385: 2382: 2379: 2376: 2373: 2370: 2367: 2364: 2361: 2358: 2355: 2352: 2349: 2330: 2327: 2307: 2276: 2273: 2270: 2267: 2264: 2261: 2258: 2255: 2252: 2249: 2246: 2243: 2240: 2237: 2234: 2231: 2228: 2225: 2222: 2219: 2216: 2213: 2210: 2190: 2185: 2163: 2160: 2157: 2137: 2134: 2131: 2128: 2109: 2106: 2087: 2084: 2044: 2032:family of sets 2019: 1992: 1989: 1977: 1974: 1971: 1968: 1965: 1962: 1959: 1956: 1953: 1950: 1930: 1927: 1924: 1904: 1876: 1856: 1853: 1850: 1847: 1844: 1841: 1838: 1835: 1832: 1829: 1809: 1806: 1803: 1783: 1771: 1768: 1755: 1752: 1749: 1746: 1743: 1740: 1737: 1717: 1714: 1711: 1708: 1705: 1702: 1699: 1696: 1693: 1690: 1687: 1684: 1681: 1678: 1675: 1672: 1669: 1666: 1663: 1660: 1657: 1654: 1635: 1632: 1608: 1605: 1585: 1565: 1545: 1525: 1522: 1519: 1516: 1513: 1510: 1507: 1495: 1492: 1479: 1467: 1464: 1447: 1427: 1407: 1387: 1384: 1381: 1378: 1375: 1368: 1363: 1360: 1356: 1352: 1348: 1342: 1337: 1333: 1329: 1310: 1307: 1304: 1299: 1294: 1289: 1260: 1257: 1234: 1229: 1215: 1212: 1209: 1205: 1202:is said to be 1191: 1171: 1168: 1163: 1159: 1155: 1152: 1147: 1142: 1139: 1136: 1132: 1128: 1124: 1118: 1114: 1108: 1103: 1100: 1097: 1093: 1088: 1084: 1064: 1059: 1036: 1033: 1028: 1024: 1020: 1017: 1014: 1009: 1005: 1001: 996: 992: 977:σ-algebra 961: 946: 943: 931: 926: 902: 898: 894: 891: 888: 883: 879: 875: 870: 866: 844: 839: 835: 831: 827: 822: 817: 814: 811: 807: 803: 799: 793: 789: 783: 778: 775: 772: 768: 763: 759: 743:is undefined. 732: 729: 726: 706: 703: 683: 680: 660: 657: 654: 651: 648: 645: 642: 639: 636: 633: 630: 627: 624: 621: 618: 615: 612: 591: 586: 559: 539: 530:, if whenever 503: 479: 476: 473: 470: 467: 464: 441: 426:defined on an 411: 399: 396: 352: 349: 344: 340: 336: 333: 328: 323: 320: 317: 313: 309: 305: 299: 295: 289: 284: 281: 278: 274: 269: 265: 217: 214: 211: 208: 205: 202: 199: 196: 193: 190: 187: 184: 181: 178: 175: 172: 169: 141: 117: 116: 31: 29: 22: 15: 13: 10: 9: 6: 4: 3: 2: 3930: 3919: 3916: 3914: 3911: 3910: 3908: 3894: 3890: 3886: 3884:0-12-095780-9 3880: 3876: 3875: 3867: 3864: 3860: 3854: 3851: 3844: 3842: 3841: 3839: 3835: 3826: 3823: 3821: 3818: 3816: 3813: 3810: 3807: 3804: 3801: 3798: 3795: 3792: 3789: 3783: 3780: 3777: 3774: 3773: 3769: 3767: 3765: 3761: 3757: 3753: 3749: 3745: 3741: 3733: 3731: 3712: 3708: 3701: 3681: 3661: 3653: 3637: 3634: 3631: 3628: 3625: 3622: 3619: 3616: 3613: 3590: 3587: 3584: 3581: 3578: 3572: 3567: 3563: 3553: 3540: 3537: 3531: 3525: 3502: 3499: 3476: 3473: 3467: 3461: 3458: 3455: 3447: 3423: 3407: 3387: 3378: 3375: 3372: 3366: 3363: 3357: 3354: 3349: 3346: 3333: 3325: 3319: 3313: 3284: 3268: 3256: 3254: 3252: 3248: 3244: 3240: 3224: 3196: 3191: 3189: 3185: 3180: 3161: 3157: 3150: 3140: 3137: 3134: 3130: 3126: 3122: 3116: 3112: 3101: 3098: 3095: 3091: 3086: 3082: 3062: 3059: 3054: 3050: 3046: 3043: 3040: 3035: 3031: 3027: 3022: 3018: 3008: 2988: 2985: 2982: 2979: 2967: 2960: 2957: 2954: 2942: 2936: 2931: 2925: 2919: 2912:, such that 2911: 2907: 2891: 2879: 2877: 2864: 2858: 2852: 2849: 2843: 2837: 2834: 2828: 2822: 2816: 2793: 2787: 2784: 2778: 2772: 2752: 2749: 2746: 2734: 2732: 2730: 2725: 2723: 2722: 2721:subadditivity 2717: 2716: 2715:submodularity 2710: 2697: 2691: 2688: 2685: 2679: 2676: 2673: 2667: 2661: 2655: 2652: 2646: 2640: 2634: 2614: 2608: 2602: 2596: 2590: 2584: 2578: 2572: 2569: 2566: 2560: 2557: 2554: 2551: 2528: 2522: 2516: 2510: 2507: 2504: 2498: 2495: 2472: 2466: 2460: 2454: 2451: 2448: 2442: 2439: 2431: 2416: 2410: 2404: 2401: 2395: 2389: 2386: 2380: 2377: 2374: 2368: 2365: 2359: 2356: 2353: 2347: 2328: 2325: 2305: 2296: 2294: 2271: 2265: 2262: 2256: 2250: 2247: 2241: 2238: 2235: 2229: 2226: 2220: 2217: 2214: 2208: 2188: 2161: 2158: 2155: 2135: 2132: 2129: 2126: 2107: 2104: 2085: 2082: 2074: 2073: 2064: 2033: 2017: 2010: 2004: 1998: 1990: 1988: 1975: 1969: 1963: 1960: 1954: 1948: 1928: 1925: 1922: 1902: 1894: 1874: 1854: 1848: 1842: 1839: 1833: 1827: 1807: 1804: 1801: 1781: 1769: 1767: 1753: 1750: 1747: 1735: 1715: 1703: 1700: 1694: 1688: 1685: 1676: 1673: 1667: 1664: 1658: 1652: 1633: 1630: 1622: 1603: 1583: 1543: 1523: 1520: 1517: 1505: 1493: 1491: 1477: 1465: 1463: 1461: 1460:inner regular 1445: 1425: 1405: 1385: 1379: 1373: 1361: 1358: 1350: 1346: 1335: 1331: 1327: 1308: 1305: 1302: 1292: 1278: 1274: 1271:If for every 1258: 1255: 1248: 1232: 1213: 1211: 1207: 1203: 1189: 1169: 1161: 1157: 1150: 1140: 1137: 1134: 1130: 1126: 1122: 1116: 1112: 1101: 1098: 1095: 1091: 1086: 1082: 1062: 1034: 1031: 1026: 1022: 1018: 1015: 1012: 1007: 1003: 999: 994: 990: 982: 978: 949:Suppose that 944: 942: 929: 900: 896: 892: 889: 886: 881: 877: 873: 868: 864: 842: 837: 833: 829: 825: 820: 815: 812: 809: 805: 801: 797: 791: 787: 781: 776: 773: 770: 766: 761: 757: 749: 744: 727: 701: 678: 658: 652: 646: 643: 637: 631: 628: 622: 619: 616: 610: 589: 573: 572:disjoint sets 557: 537: 529: 521: 501: 493: 471: 465: 429: 425: 409: 397: 395: 393: 389: 388: 382: 380: 376: 372: 368: 363: 350: 342: 338: 331: 321: 318: 315: 311: 307: 303: 297: 293: 282: 279: 276: 272: 267: 263: 255: 251: 247: 243: 239: 235: 231: 215: 209: 203: 200: 194: 188: 185: 179: 176: 173: 167: 159: 155: 139: 132: 128: 124: 113: 110: 102: 91: 88: 84: 81: 77: 74: 70: 67: 63: 60: –  59: 55: 54:Find sources: 48: 44: 38: 37: 32:This article 30: 26: 21: 20: 3873: 3866: 3858: 3853: 3831: 3830: 3820:τ-additivity 3776:Additive map 3748:vector space 3737: 3554: 3446:Banach limit 3420:denotes the 3283:real numbers 3260: 3250: 3246: 3242: 3194: 3192: 3181: 3009: 2910:real numbers 2883: 2738: 2729:modular form 2726: 2720: 2714: 2711: 2429: 2297: 2288: 2075:if whenever 2066: 2058: 2057:is called a 2009:set function 2006: 1888: 1773: 1770:Monotonicity 1620: 1497: 1469: 1398:we say that 1217: 948: 745: 523: 515: 424:set function 401: 385: 383: 364: 249: 245: 241: 238:set function 233: 229: 126: 120: 105: 96: 86: 79: 72: 65: 53: 41:Please help 36:verification 33: 1208:𝜎-additive 1182:holds then 123:mathematics 3907:Categories 3845:References 3834:PlanetMath 2291:modularity 2001:See also: 1995:See also: 1991:Modularity 1466:Properties 1245:we have a 514:is called 392:modularity 99:April 2024 69:newspapers 3702:μ 3682:μ 3662:μ 3638:… 3526:μ 3506:∞ 3474:≤ 3462:μ 3459:≤ 3408:λ 3367:∩ 3358:λ 3355:⋅ 3340:∞ 3337:→ 3314:μ 3269:μ 3205:∅ 3151:μ 3146:∞ 3131:∑ 3107:∞ 3092:⋃ 3083:μ 3063:… 3044:… 2983:∉ 2958:∈ 2920:μ 2906:power set 2892:μ 2853:μ 2850:− 2838:μ 2826:∖ 2817:μ 2788:μ 2785:− 2773:μ 2750:⊆ 2689:∩ 2680:μ 2665:∖ 2656:μ 2644:∖ 2635:μ 2606:∖ 2597:∪ 2588:∖ 2579:∪ 2570:∩ 2555:∪ 2526:∖ 2517:∪ 2508:∩ 2470:∖ 2461:∪ 2452:∩ 2405:μ 2390:μ 2378:∩ 2369:μ 2357:∪ 2348:μ 2266:ϕ 2251:ϕ 2239:∩ 2230:ϕ 2218:∪ 2209:ϕ 2159:∩ 2130:∪ 2070:valuation 2018:μ 1964:μ 1961:≥ 1949:μ 1926:⊆ 1903:μ 1875:μ 1867:That is, 1843:μ 1840:≤ 1828:μ 1805:⊆ 1782:μ 1748:≠ 1742:∅ 1736:μ 1710:∅ 1704:μ 1689:μ 1680:∅ 1677:∪ 1668:μ 1653:μ 1607:∞ 1604:− 1584:μ 1564:∞ 1544:μ 1512:∅ 1506:μ 1478:μ 1446:μ 1426:τ 1406:μ 1374:μ 1362:∈ 1336:⋃ 1328:μ 1306:τ 1303:∩ 1293:⊆ 1277:open sets 1256:τ 1190:μ 1151:μ 1146:∞ 1131:∑ 1107:∞ 1092:⋃ 1083:μ 1035:… 1016:… 890:… 826:μ 806:∑ 767:⋃ 758:μ 731:∞ 728:− 725:∞ 705:∞ 682:∞ 679:− 647:μ 632:μ 620:∪ 611:μ 502:μ 490:(see the 475:∞ 469:∞ 466:− 410:μ 384:The term 332:μ 327:∞ 312:∑ 288:∞ 273:⋃ 264:μ 204:μ 189:μ 177:∪ 168:μ 140:μ 3893:21196971 3825:ba space 3770:See also 3239:ba space 2880:Examples 2432:: write 1596:assigns 1556:assigns 1273:directed 1247:topology 981:sequence 856:for any 518:additive 367:measures 246:infinite 158:disjoint 131:function 3489:and if 3247:bounded 3243:bounded 3184:measure 3179:holds. 2908:of the 1498:Either 394:below. 156:of two 83:scholar 3891:  3881:  3740:monoid 3654:, and 3400:where 3195:charge 2298:Given 2065:and a 379:volume 371:length 85:  78:  71:  64:  56:  3744:group 3518:then 3237:(Cf. 2430:Proof 2201:then 2030:on a 1941:then 1887:is a 1820:then 1621:Proof 975:is a 603:then 422:be a 154:union 129:is a 125:, an 90:JSTOR 76:books 3889:OCLC 3879:ISBN 3606:for 3503:< 3444:the 3424:and 3186:and 3182:See 2765:and 2718:and 2544:and 2488:and 2318:and 2148:and 694:and 570:are 550:and 402:Let 375:area 62:news 3497:sup 3432:lim 3330:lim 3253:.) 3217:to 3010:If 2739:If 1774:If 1728:If 1536:or 1458:is 1418:is 1355:sup 1206:or 574:in 522:or 121:In 45:by 3909:: 3887:. 3766:. 3541:0. 3225:0. 3193:A 2731:. 2007:A 377:, 373:, 3895:. 3840:. 3718:) 3713:n 3709:A 3705:( 3635:, 3632:2 3629:, 3626:1 3623:, 3620:0 3617:= 3614:n 3594:) 3591:1 3588:+ 3585:n 3582:, 3579:n 3576:[ 3573:= 3568:n 3564:A 3538:= 3535:) 3532:A 3529:( 3500:A 3477:1 3471:) 3468:A 3465:( 3456:0 3388:, 3385:) 3382:) 3379:k 3376:, 3373:0 3370:( 3364:A 3361:( 3350:k 3347:1 3334:k 3326:= 3323:) 3320:A 3317:( 3293:R 3251:R 3167:) 3162:n 3158:A 3154:( 3141:1 3138:= 3135:n 3127:= 3123:) 3117:n 3113:A 3102:1 3099:= 3096:n 3087:( 3060:, 3055:n 3051:A 3047:, 3041:, 3036:2 3032:A 3028:, 3023:1 3019:A 2989:. 2986:A 2980:0 2968:0 2961:A 2955:0 2943:1 2937:{ 2932:= 2929:) 2926:A 2923:( 2865:. 2862:) 2859:A 2856:( 2847:) 2844:B 2841:( 2835:= 2832:) 2829:A 2823:B 2820:( 2797:) 2794:A 2791:( 2782:) 2779:B 2776:( 2753:B 2747:A 2698:. 2695:) 2692:B 2686:A 2683:( 2677:2 2674:+ 2671:) 2668:A 2662:B 2659:( 2653:+ 2650:) 2647:B 2641:A 2638:( 2615:, 2612:) 2609:A 2603:B 2600:( 2594:) 2591:B 2585:A 2582:( 2576:) 2573:B 2567:A 2564:( 2561:= 2558:B 2552:A 2532:) 2529:A 2523:B 2520:( 2514:) 2511:B 2505:A 2502:( 2499:= 2496:B 2476:) 2473:B 2467:A 2464:( 2458:) 2455:B 2449:A 2446:( 2443:= 2440:A 2417:. 2414:) 2411:B 2408:( 2402:+ 2399:) 2396:A 2393:( 2387:= 2384:) 2381:B 2375:A 2372:( 2366:+ 2363:) 2360:B 2354:A 2351:( 2329:, 2326:B 2306:A 2275:) 2272:B 2269:( 2263:+ 2260:) 2257:A 2254:( 2248:= 2245:) 2242:B 2236:A 2233:( 2227:+ 2224:) 2221:B 2215:A 2212:( 2189:, 2184:S 2162:B 2156:A 2136:, 2133:B 2127:A 2108:, 2105:B 2086:, 2083:A 2043:S 1976:. 1973:) 1970:B 1967:( 1958:) 1955:A 1952:( 1929:B 1923:A 1855:. 1852:) 1849:B 1846:( 1837:) 1834:A 1831:( 1808:B 1802:A 1754:, 1751:0 1745:) 1739:( 1716:. 1713:) 1707:( 1701:+ 1698:) 1695:A 1692:( 1686:= 1683:) 1674:A 1671:( 1665:= 1662:) 1659:A 1656:( 1634:, 1631:A 1524:, 1521:0 1518:= 1515:) 1509:( 1386:, 1383:) 1380:G 1377:( 1367:G 1359:G 1351:= 1347:) 1341:G 1332:( 1309:, 1298:A 1288:G 1259:. 1233:, 1228:A 1170:, 1167:) 1162:n 1158:A 1154:( 1141:1 1138:= 1135:n 1127:= 1123:) 1117:n 1113:A 1102:1 1099:= 1096:n 1087:( 1063:, 1058:A 1032:, 1027:n 1023:A 1019:, 1013:, 1008:2 1004:A 1000:, 995:1 991:A 960:A 930:. 925:A 901:N 897:A 893:, 887:, 882:2 878:A 874:, 869:1 865:A 843:) 838:n 834:A 830:( 821:N 816:1 813:= 810:n 802:= 798:) 792:n 788:A 782:N 777:1 774:= 771:n 762:( 702:+ 659:. 656:) 653:B 650:( 644:+ 641:) 638:A 635:( 629:= 626:) 623:B 617:A 614:( 590:, 585:A 558:B 538:A 478:] 472:, 463:[ 440:A 351:. 348:) 343:n 339:A 335:( 322:1 319:= 316:n 308:= 304:) 298:n 294:A 283:1 280:= 277:n 268:( 234:k 230:k 216:. 213:) 210:B 207:( 201:+ 198:) 195:A 192:( 186:= 183:) 180:B 174:A 171:( 112:) 106:( 101:) 97:( 87:· 80:· 73:· 66:· 39:.

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