Knowledge

Direct limit

Source 📝

5045: 2797: 5292: 5312: 5302: 4570:
In the literature, one finds the terms "directed limit", "direct inductive limit", "directed colimit", "direct colimit" and "inductive limit" for the concept of direct limit defined above. The term "inductive limit" is ambiguous however, as some authors use it for the general concept of colimit.
4349:
and form the colimit of this functor. One can show that a category has all directed limits if and only if it has all filtered colimits, and a functor defined on such a category commutes with all direct limits if and only if it commutes with all filtered colimits.
3387: 3845: 4025: 1546: 2185: 1989: 4251: 1829:. Intuitively, two elements in the disjoint union are equivalent if and only if they "eventually become equal" in the direct system. An equivalent formulation that highlights the duality to the 1049: 2948:
Unlike for algebraic objects, not every direct system in an arbitrary category has a direct limit. If it does, however, the direct limit is unique in a strong sense: given another direct limit
2431: 3921: 4296: 2513: 3311: 1827: 4521: 4486: 3192: 2916: 2588: 2273: 2079: 1366: 1286: 233: 2708: 2669: 2630: 2340: 2786: 3472: 1891: 1201: 525: 4093: 919: 2740: 3237:) that enlarges matrices by putting a 1 in the lower right corner and zeros elsewhere in the last row and column. The direct limit of this system is the general linear group of 2864: 2030: 1670: 2119: 1406: 968: 791: 478: 441: 4549: 4451: 4423: 4399: 4375: 4347: 4323: 4166: 4120: 4057: 2385: 2297: 2220: 1629: 1589: 3054: 1233: 187: 2943: 1109: 4194: 2539: 1917: 1748: 1722: 1466: 1137: 1075: 2457: 1696: 3146: 3000: 1437: 708: 3525: 2361: 993: 4214: 4140: 3499: 3431: 3407: 3316: 3119: 3096: 3020: 1310: 751: 728: 3735: 3926: 651:
is a way to construct a (typically large) object from many (typically smaller) objects that are put together in a specific way. These objects may be
3249:) can be thought of as an infinite invertible matrix that differs from the infinite identity matrix in only finitely many entries. The group GL( 630: 1475: 2124: 1928: 4689: 4562:. As above, inverse limits can be viewed as limits of certain functors and are closely related to limits over cofiltered categories. 4655: 4974: 4222: 87: 998: 2390: 3861: 4267: 5336: 4611: 2462: 623: 575: 3274: 4426: 1753: 793:. This notation suppresses the system of homomorphisms; however, the limit depends on the system of homomorphisms. 4491: 4456: 3151: 2872: 2544: 2229: 2035: 1322: 1242: 197: 2674: 2635: 2596: 2306: 2745: 3702: 3439: 1836: 1144: 492: 4682: 4660: 4066: 892: 2713: 4886: 4841: 616: 483: 5315: 5255: 3528: 333: 4964: 2823: 1994: 5305: 5091: 4955: 4863: 2032:
are defined such that these maps become homomorphisms. Formally, the direct limit of the direct system
1634: 93: 2084: 1371: 928: 756: 454: 417: 108: 5341: 5264: 4908: 4846: 4769: 4530: 4432: 4404: 4380: 4356: 4328: 4304: 4145: 4101: 4038: 2366: 2278: 2201: 1594: 1554: 5295: 5251: 4856: 4675: 3029: 1206: 568: 371: 321: 170: 4851: 4833: 4254: 813: 797: 380: 114: 73: 5058: 4824: 4804: 4727: 4580: 4555: 2921: 2196: 1527: 837: 805: 664: 537: 388: 339: 120: 1083: 4940: 4779: 4173: 2518: 1896: 1833:
is that an element is equivalent to all its images under the maps of the direct system, i.e.
1727: 1701: 1450: 1114: 1054: 2436: 1675: 4752: 4747: 4643: 3851: 3478: 3206: 3124: 2978: 1445: 1415: 869: 865: 833: 686: 261: 135: 3382:{\displaystyle \mathbb {Z} /p^{n}\mathbb {Z} \rightarrow \mathbb {Z} /p^{n+1}\mathbb {Z} } 8: 5096: 5044: 4970: 4774: 3608: 3543: 3504: 2803: 2345: 977: 873: 857: 853: 829: 825: 652: 543: 351: 302: 247: 141: 127: 55: 23: 4950: 4945: 4927: 4809: 4784: 4199: 4125: 3840:{\displaystyle \mathrm {Hom} (\varinjlim X_{i},Y)=\varprojlim \mathrm {Hom} (X_{i},Y).} 3686: 3484: 3416: 3392: 3254: 3104: 3081: 3005: 2223: 1295: 883: 861: 736: 713: 672: 656: 556: 42: 5259: 5196: 5184: 5086: 5011: 5006: 4960: 4742: 4737: 4650: 4607: 4299: 4261: 4217: 3547: 849: 676: 597: 394: 159: 100: 5220: 5106: 5081: 5016: 5001: 4996: 4935: 4764: 4732: 4631: 3099: 603: 589: 403: 345: 308: 81: 67: 4020:{\displaystyle 0\to \varinjlim A_{i}\to \varinjlim B_{i}\to \varinjlim C_{i}\to 0} 5132: 4698: 4639: 4601: 1440: 801: 365: 315: 153: 3434: 683:
in the category) between those smaller objects. The direct limit of the objects
5169: 5164: 5148: 5111: 5101: 5021: 4257:
of this functor is the same as the direct limit of the original direct system.
4168: 4096: 3858:. This means that if you start with a directed system of short exact sequences 3706: 3410: 3269: 1409: 409: 5330: 5159: 4991: 4868: 4794: 4559: 3855: 3726: 3068: 3023: 1830: 809: 550: 446: 61: 4814: 3265: 3026:
by inclusion. If the collection is directed, its direct limit is the union
1991:
sending each element to its equivalence class. The algebraic operations on
922: 878: 731: 668: 660: 582: 357: 253: 5174: 5154: 5026: 4896: 2956: 644: 562: 273: 147: 29: 2796: 5206: 5144: 4757: 4524: 3713: 3121:. The direct limit of any corresponding direct system is isomorphic to 3072: 327: 4425:(consider for example the category of finite sets, or the category of 3850:
An important property is that taking direct limits in the category of
3606:
is the restriction map. The direct limit of this system is called the
3477:
There is a (non-obvious) injective ring homomorphism from the ring of
5200: 4891: 3527:
variables. Forming the direct limit of this direct system yields the
971: 287: 192: 5269: 4901: 4799: 3057: 1541:{\displaystyle \varinjlim A_{i}=\bigsqcup _{i}A_{i}{\bigg /}\sim .} 680: 281: 267: 4667: 5239: 5229: 4878: 4789: 4060: 3061: 2180:{\displaystyle \phi _{j}\colon A_{j}\rightarrow \varinjlim A_{i}} 1984:{\displaystyle \phi _{j}\colon A_{j}\rightarrow \varinjlim A_{i}} 165: 49: 848:
In this section objects are understood to consist of underlying
5234: 5116: 667:. The way they are put together is specified by a system of 4030: 836:, and then the general definition, which can be used in any 3923:
and form direct limits, you obtain a short exact sequence
2190: 4246:{\displaystyle {\mathcal {I}}\rightarrow {\mathcal {C}}} 3409:. The direct limit of this system consists of all the 4533: 4494: 4459: 4435: 4407: 4383: 4359: 4331: 4307: 4270: 4225: 4202: 4176: 4148: 4128: 4104: 4069: 4041: 3929: 3864: 3738: 3507: 3487: 3442: 3419: 3395: 3319: 3277: 3154: 3127: 3107: 3084: 3032: 3008: 2981: 2924: 2875: 2826: 2748: 2716: 2677: 2638: 2599: 2547: 2521: 2465: 2439: 2393: 2369: 2348: 2309: 2281: 2232: 2204: 2127: 2087: 2038: 1997: 1931: 1899: 1839: 1756: 1730: 1704: 1678: 1637: 1597: 1557: 1478: 1453: 1418: 1408:
and is defined as follows. Its underlying set is the
1374: 1325: 1298: 1245: 1209: 1147: 1117: 1086: 1057: 1001: 980: 931: 895: 843: 759: 739: 716: 689: 495: 457: 420: 200: 173: 1044:{\displaystyle f_{ij}\colon A_{i}\rightarrow A_{j}} 796:Direct limits are a special case of the concept of 4543: 4515: 4488:in which all direct limits exist; the objects of 4480: 4445: 4417: 4393: 4369: 4341: 4317: 4290: 4260:A notion closely related to direct limits are the 4245: 4208: 4188: 4160: 4134: 4114: 4087: 4051: 4019: 3915: 3839: 3519: 3501:variables to the ring of symmetric polynomials in 3493: 3466: 3425: 3401: 3381: 3305: 3186: 3140: 3113: 3090: 3048: 3014: 2994: 2937: 2910: 2858: 2780: 2734: 2702: 2663: 2624: 2582: 2533: 2507: 2451: 2426:{\displaystyle \phi _{i}\colon X_{i}\rightarrow X} 2425: 2379: 2355: 2334: 2291: 2267: 2214: 2179: 2113: 2073: 2024: 1983: 1911: 1885: 1821: 1742: 1716: 1690: 1664: 1623: 1583: 1540: 1460: 1431: 1400: 1360: 1304: 1280: 1227: 1195: 1131: 1103: 1069: 1043: 987: 962: 913: 785: 745: 722: 702: 519: 472: 435: 227: 181: 3916:{\displaystyle 0\to A_{i}\to B_{i}\to C_{i}\to 0} 5328: 4291:{\displaystyle {\mathcal {J}}\to {\mathcal {C}}} 3056:. The same is true for a directed collection of 2195:The direct limit can be defined in an arbitrary 2508:{\displaystyle \phi _{i}=\phi _{j}\circ f_{ij}} 2275:be a direct system of objects and morphisms in 4059:admits an alternative description in terms of 3306:{\displaystyle \mathbb {Z} /p^{n}\mathbb {Z} } 3060:of a given group, or a directed collection of 4683: 4663:, vol. 5 (2nd ed.), Springer-Verlag 4603:Locally Presentable and Accessible Categories 4599: 3709:on the underlying set-theoretic direct limit. 3268:. Consider the direct system composed of the 1822:{\displaystyle f_{ik}(x_{i})=f_{jk}(x_{j})\,} 882:are understood in the corresponding setting ( 624: 4516:{\displaystyle {\text{Ind}}({\mathcal {C}})} 4481:{\displaystyle {\text{Ind}}({\mathcal {C}})} 4082: 4070: 3187:{\displaystyle \phi _{m}:X_{m}\rightarrow X} 2966:that commutes with the canonical morphisms. 2911:{\displaystyle \langle X_{i},f_{ij}\rangle } 2905: 2876: 2697: 2678: 2658: 2639: 2619: 2600: 2583:{\displaystyle \langle X_{i},f_{ij}\rangle } 2577: 2548: 2329: 2310: 2268:{\displaystyle \langle X_{i},f_{ij}\rangle } 2262: 2233: 2074:{\displaystyle \langle A_{i},f_{ij}\rangle } 2068: 2039: 1361:{\displaystyle \langle A_{i},f_{ij}\rangle } 1355: 1326: 1281:{\displaystyle \langle A_{i},f_{ij}\rangle } 1275: 1246: 957: 932: 908: 896: 228:{\displaystyle 0=\mathbb {Z} /1\mathbb {Z} } 4035:We note that a direct system in a category 2703:{\displaystyle \langle Y,\psi _{i}\rangle } 2664:{\displaystyle \langle X,\phi _{i}\rangle } 2625:{\displaystyle \langle X,\phi _{i}\rangle } 2335:{\displaystyle \langle X,\phi _{i}\rangle } 5311: 5301: 5057: 4690: 4676: 4638:, Translated from French, Paris: Hermann, 4606:. Cambridge University Press. p. 15. 3565:form a directed set ordered by inclusion ( 2781:{\displaystyle u\circ \phi _{i}=\psi _{i}} 2121:together with the canonical homomorphisms 631: 617: 16:Special case of colimit in category theory 4264:. Here we start with a covariant functor 4031:Related constructions and generalizations 3467:{\displaystyle \mathbb {Z} (p^{\infty })} 3444: 3375: 3349: 3341: 3321: 3299: 3279: 2352: 2021: 1886:{\displaystyle x_{i}\sim \,f_{ij}(x_{i})} 1853: 1818: 1651: 1457: 1196:{\displaystyle f_{ik}=f_{jk}\circ f_{ij}} 1128: 1100: 984: 520:{\displaystyle \mathbb {Z} (p^{\infty })} 497: 460: 423: 221: 208: 175: 4656:Categories for the Working Mathematician 4649: 4630: 4636:Elements of mathematics. Theory of sets 4088:{\displaystyle \langle I,\leq \rangle } 3581:). The corresponding direct system is ( 914:{\displaystyle \langle I,\leq \rangle } 5329: 2735:{\displaystyle u\colon X\rightarrow Y} 2541:. A direct limit of the direct system 2191:Direct limits in an arbitrary category 824:We will first give the definition for 5056: 4709: 4671: 4429:). In this case, we can always embed 819: 88:Free product of associative algebras 4697: 3201:be a field. For a positive integer 13: 4558:of the direct limit is called the 4536: 4505: 4470: 4438: 4410: 4401:that don't have a direct limit in 4386: 4362: 4334: 4310: 4283: 4273: 4238: 4228: 4107: 4044: 3808: 3805: 3802: 3746: 3743: 3740: 3456: 3225:. We have a group homomorphism GL( 2859:{\displaystyle X=\varinjlim X_{i}} 2817:The direct limit is often denoted 2372: 2284: 2207: 2025:{\displaystyle \varinjlim A_{i}\,} 844:Direct limits of algebraic objects 509: 14: 5353: 4427:finitely generated abelian groups 4377:, there may be direct systems in 3716:is an inductive limit of schemes. 1922:One obtains from this definition 1665:{\displaystyle x_{i}\sim \,x_{j}} 576:Noncommutative algebraic geometry 5310: 5300: 5291: 5290: 5043: 4710: 4600:Adamek, J.; Rosicky, J. (1994). 2795: 2671:is a target and for each target 2114:{\displaystyle \varinjlim A_{i}} 1401:{\displaystyle \varinjlim A_{i}} 963:{\displaystyle \{A_{i}:i\in I\}} 786:{\displaystyle \varinjlim A_{i}} 473:{\displaystyle \mathbb {Q} _{p}} 436:{\displaystyle \mathbb {Z} _{p}} 4122:whose objects are the elements 1077:with the following properties: 663:or in general objects from any 4593: 4565: 4544:{\displaystyle {\mathcal {C}}} 4510: 4500: 4475: 4465: 4446:{\displaystyle {\mathcal {C}}} 4418:{\displaystyle {\mathcal {C}}} 4394:{\displaystyle {\mathcal {C}}} 4370:{\displaystyle {\mathcal {C}}} 4342:{\displaystyle {\mathcal {C}}} 4318:{\displaystyle {\mathcal {J}}} 4278: 4233: 4161:{\displaystyle i\rightarrow j} 4152: 4115:{\displaystyle {\mathcal {I}}} 4052:{\displaystyle {\mathcal {C}}} 4011: 3985: 3959: 3933: 3907: 3894: 3881: 3868: 3831: 3812: 3782: 3750: 3703:category of topological spaces 3461: 3448: 3345: 3178: 2726: 2417: 2380:{\displaystyle {\mathcal {C}}} 2292:{\displaystyle {\mathcal {C}}} 2215:{\displaystyle {\mathcal {C}}} 2151: 1955: 1880: 1867: 1815: 1802: 1783: 1770: 1624:{\displaystyle x_{j}\in A_{j}} 1584:{\displaystyle x_{i}\in A_{i}} 1028: 812:, which are a special case of 514: 501: 1: 4661:Graduate Texts in Mathematics 4624: 3720: 3389:induced by multiplication by 3221:- matrices with entries from 3075:is defined as a direct limit. 3049:{\displaystyle \bigcup M_{i}} 2710:, there is a unique morphism 1672:if and only if there is some 1228:{\displaystyle i\leq j\leq k} 4353:Given an arbitrary category 3725:Direct limits are linked to 3561:. The open neighborhoods of 3253:) is of vital importance in 2918:and the canonical morphisms 2592:universally repelling target 182:{\displaystyle \mathbb {Z} } 7: 4985:Constructions on categories 4574: 3529:ring of symmetric functions 3213:) consisting of invertible 3148:and the canonical morphism 3098:be any directed set with a 2969: 876:), etc. With this in mind, 334:Unique factorization domain 10: 5358: 5092:Higher-dimensional algebra 4142:and there is a morphisms 1051:be a homomorphism for all 94:Tensor product of algebras 5286: 5219: 5183: 5131: 5124: 5075: 5065: 5052: 5041: 4984: 4926: 4877: 4832: 4823: 4720: 4716: 4705: 3705:are given by placing the 3637:, the canonical morphism 2938:{\displaystyle \phi _{i}} 5337:Limits (category theory) 4586: 3654:associates to a section 3629:. For each neighborhood 2975:A collection of subsets 2792:. The following diagram 1104:{\displaystyle f_{ii}\,} 372:Formal power series ring 322:Integrally closed domain 4902:Cokernels and quotients 4825:Universal constructions 4581:Direct limits of groups 4196:. A direct system over 4189:{\displaystyle i\leq j} 4095:can be considered as a 3413:of order some power of 2869:with the direct system 2534:{\displaystyle i\leq j} 2433:are morphisms for each 2081:consists of the object 1912:{\displaystyle i\leq j} 1743:{\displaystyle j\leq k} 1717:{\displaystyle i\leq k} 1461:{\displaystyle \sim \,} 1132:{\displaystyle A_{i}\,} 1070:{\displaystyle i\leq j} 970:be a family of objects 381:Algebraic number theory 74:Total ring of fractions 5059:Higher category theory 4805:Natural transformation 4545: 4517: 4482: 4447: 4419: 4395: 4371: 4343: 4319: 4292: 4247: 4216:is then the same as a 4210: 4190: 4162: 4136: 4116: 4089: 4053: 4021: 3917: 3841: 3521: 3495: 3468: 3427: 3403: 3383: 3313:and the homomorphisms 3307: 3188: 3142: 3115: 3092: 3050: 3016: 2996: 2939: 2912: 2860: 2782: 2736: 2704: 2665: 2626: 2584: 2535: 2509: 2453: 2452:{\displaystyle i\in I} 2427: 2381: 2357: 2336: 2299:(as defined above). A 2293: 2269: 2216: 2181: 2115: 2075: 2026: 1985: 1913: 1887: 1823: 1744: 1718: 1692: 1691:{\displaystyle k\in I} 1666: 1625: 1585: 1542: 1462: 1433: 1402: 1362: 1306: 1282: 1229: 1197: 1133: 1105: 1071: 1045: 989: 964: 915: 852:equipped with a given 787: 747: 724: 704: 538:Noncommutative algebra 521: 474: 437: 389:Algebraic number field 340:Principal ideal domain 229: 183: 121:Frobenius endomorphism 4546: 4518: 4483: 4448: 4420: 4396: 4372: 4344: 4320: 4293: 4248: 4211: 4191: 4163: 4137: 4117: 4090: 4054: 4022: 3918: 3842: 3701:Direct limits in the 3522: 3496: 3479:symmetric polynomials 3469: 3428: 3404: 3384: 3308: 3189: 3143: 3141:{\displaystyle X_{m}} 3116: 3093: 3064:of a given ring, etc. 3051: 3017: 2997: 2995:{\displaystyle M_{i}} 2940: 2913: 2861: 2783: 2737: 2705: 2666: 2627: 2585: 2536: 2510: 2454: 2428: 2382: 2358: 2337: 2294: 2270: 2217: 2182: 2116: 2076: 2027: 1986: 1914: 1888: 1824: 1745: 1719: 1693: 1667: 1626: 1586: 1543: 1463: 1434: 1432:{\displaystyle A_{i}} 1403: 1363: 1319:of the direct system 1307: 1283: 1230: 1198: 1134: 1106: 1072: 1046: 990: 965: 916: 868:(over a fixed ring), 788: 748: 725: 705: 703:{\displaystyle A_{i}} 522: 475: 438: 230: 184: 4928:Algebraic categories 4531: 4492: 4457: 4433: 4405: 4381: 4357: 4329: 4305: 4268: 4223: 4200: 4174: 4146: 4126: 4102: 4067: 4039: 3927: 3862: 3736: 3505: 3485: 3440: 3433:, and is called the 3417: 3393: 3317: 3275: 3245:). An element of GL( 3207:general linear group 3152: 3125: 3105: 3082: 3030: 3006: 2979: 2922: 2873: 2824: 2746: 2714: 2675: 2636: 2597: 2545: 2519: 2463: 2437: 2391: 2367: 2346: 2307: 2279: 2230: 2202: 2125: 2085: 2036: 1995: 1929: 1897: 1837: 1754: 1728: 1702: 1676: 1635: 1595: 1555: 1476: 1451: 1446:equivalence relation 1416: 1372: 1323: 1296: 1243: 1207: 1145: 1115: 1084: 1055: 999: 978: 929: 893: 826:algebraic structures 816:in category theory. 804:. Direct limits are 757: 737: 714: 687: 544:Noncommutative rings 493: 455: 418: 262:Non-associative ring 198: 171: 128:Algebraic structures 5097:Homotopy hypothesis 4775:Commutative diagram 4063:. Any directed set 3520:{\displaystyle n+1} 2356:{\displaystyle X\,} 1924:canonical functions 1111:is the identity on 988:{\displaystyle I\,} 884:group homomorphisms 854:algebraic structure 303:Commutative algebra 142:Associative algebra 24:Algebraic structure 4810:Universal property 4651:Mac Lane, Saunders 4541: 4513: 4478: 4443: 4415: 4391: 4367: 4339: 4315: 4288: 4243: 4206: 4186: 4158: 4132: 4112: 4085: 4049: 4017: 3996: 3970: 3944: 3913: 3837: 3796: 3761: 3517: 3491: 3464: 3423: 3399: 3379: 3303: 3255:algebraic K-theory 3194:is an isomorphism. 3184: 3138: 3111: 3088: 3046: 3012: 2992: 2945:being understood. 2935: 2908: 2856: 2841: 2778: 2732: 2700: 2661: 2632:in the sense that 2622: 2580: 2531: 2505: 2449: 2423: 2377: 2353: 2332: 2289: 2265: 2224:universal property 2212: 2177: 2162: 2111: 2096: 2071: 2022: 2006: 1981: 1966: 1909: 1883: 1819: 1740: 1714: 1688: 1662: 1621: 1581: 1538: 1514: 1487: 1458: 1429: 1398: 1383: 1358: 1302: 1278: 1225: 1193: 1129: 1101: 1067: 1041: 985: 960: 911: 783: 768: 743: 720: 700: 673:group homomorphism 557:Semiprimitive ring 517: 470: 433: 241:Related structures 225: 179: 115:Inner automorphism 101:Ring homomorphisms 5324: 5323: 5282: 5281: 5278: 5277: 5260:monoidal category 5215: 5214: 5087:Enriched category 5039: 5038: 5035: 5034: 5012:Quotient category 5007:Opposite category 4922: 4921: 4632:Bourbaki, Nicolas 4498: 4463: 4325:to some category 4300:filtered category 4262:filtered colimits 4218:covariant functor 4209:{\displaystyle I} 4135:{\displaystyle I} 3989: 3963: 3937: 3789: 3754: 3548:topological space 3494:{\displaystyle n} 3426:{\displaystyle p} 3402:{\displaystyle p} 3114:{\displaystyle m} 3091:{\displaystyle X} 3024:partially ordered 3015:{\displaystyle M} 2952:′ there exists a 2834: 2155: 2089: 1999: 1959: 1505: 1480: 1376: 1305:{\displaystyle I} 820:Formal definition 761: 746:{\displaystyle I} 730:ranges over some 723:{\displaystyle i} 677:ring homomorphism 641: 640: 598:Geometric algebra 309:Commutative rings 160:Category of rings 5349: 5342:Abstract algebra 5314: 5313: 5304: 5303: 5294: 5293: 5129: 5128: 5107:Simplex category 5082:Categorification 5073: 5072: 5054: 5053: 5047: 5017:Product category 5002:Kleisli category 4997:Functor category 4842:Terminal objects 4830: 4829: 4765:Adjoint functors 4718: 4717: 4707: 4706: 4692: 4685: 4678: 4669: 4668: 4664: 4646: 4618: 4617: 4597: 4556:categorical dual 4550: 4548: 4547: 4542: 4540: 4539: 4522: 4520: 4519: 4514: 4509: 4508: 4499: 4496: 4487: 4485: 4484: 4479: 4474: 4473: 4464: 4461: 4453:into a category 4452: 4450: 4449: 4444: 4442: 4441: 4424: 4422: 4421: 4416: 4414: 4413: 4400: 4398: 4397: 4392: 4390: 4389: 4376: 4374: 4373: 4368: 4366: 4365: 4348: 4346: 4345: 4340: 4338: 4337: 4324: 4322: 4321: 4316: 4314: 4313: 4297: 4295: 4294: 4289: 4287: 4286: 4277: 4276: 4252: 4250: 4249: 4244: 4242: 4241: 4232: 4231: 4215: 4213: 4212: 4207: 4195: 4193: 4192: 4187: 4167: 4165: 4164: 4159: 4141: 4139: 4138: 4133: 4121: 4119: 4118: 4113: 4111: 4110: 4094: 4092: 4091: 4086: 4058: 4056: 4055: 4050: 4048: 4047: 4026: 4024: 4023: 4018: 4010: 4009: 3997: 3984: 3983: 3971: 3958: 3957: 3945: 3922: 3920: 3919: 3914: 3906: 3905: 3893: 3892: 3880: 3879: 3846: 3844: 3843: 3838: 3824: 3823: 3811: 3797: 3775: 3774: 3762: 3749: 3526: 3524: 3523: 3518: 3500: 3498: 3497: 3492: 3473: 3471: 3470: 3465: 3460: 3459: 3447: 3432: 3430: 3429: 3424: 3408: 3406: 3405: 3400: 3388: 3386: 3385: 3380: 3378: 3373: 3372: 3357: 3352: 3344: 3339: 3338: 3329: 3324: 3312: 3310: 3309: 3304: 3302: 3297: 3296: 3287: 3282: 3241:, written as GL( 3193: 3191: 3190: 3185: 3177: 3176: 3164: 3163: 3147: 3145: 3144: 3139: 3137: 3136: 3120: 3118: 3117: 3112: 3100:greatest element 3097: 3095: 3094: 3089: 3055: 3053: 3052: 3047: 3045: 3044: 3021: 3019: 3018: 3013: 3001: 2999: 2998: 2993: 2991: 2990: 2944: 2942: 2941: 2936: 2934: 2933: 2917: 2915: 2914: 2909: 2904: 2903: 2888: 2887: 2865: 2863: 2862: 2857: 2855: 2854: 2842: 2799: 2787: 2785: 2784: 2779: 2777: 2776: 2764: 2763: 2741: 2739: 2738: 2733: 2709: 2707: 2706: 2701: 2696: 2695: 2670: 2668: 2667: 2662: 2657: 2656: 2631: 2629: 2628: 2623: 2618: 2617: 2589: 2587: 2586: 2581: 2576: 2575: 2560: 2559: 2540: 2538: 2537: 2532: 2514: 2512: 2511: 2506: 2504: 2503: 2488: 2487: 2475: 2474: 2458: 2456: 2455: 2450: 2432: 2430: 2429: 2424: 2416: 2415: 2403: 2402: 2386: 2384: 2383: 2378: 2376: 2375: 2363:is an object in 2362: 2360: 2359: 2354: 2341: 2339: 2338: 2333: 2328: 2327: 2298: 2296: 2295: 2290: 2288: 2287: 2274: 2272: 2271: 2266: 2261: 2260: 2245: 2244: 2221: 2219: 2218: 2213: 2211: 2210: 2186: 2184: 2183: 2178: 2176: 2175: 2163: 2150: 2149: 2137: 2136: 2120: 2118: 2117: 2112: 2110: 2109: 2097: 2080: 2078: 2077: 2072: 2067: 2066: 2051: 2050: 2031: 2029: 2028: 2023: 2020: 2019: 2007: 1990: 1988: 1987: 1982: 1980: 1979: 1967: 1954: 1953: 1941: 1940: 1918: 1916: 1915: 1910: 1892: 1890: 1889: 1884: 1879: 1878: 1866: 1865: 1849: 1848: 1828: 1826: 1825: 1820: 1814: 1813: 1801: 1800: 1782: 1781: 1769: 1768: 1749: 1747: 1746: 1741: 1723: 1721: 1720: 1715: 1697: 1695: 1694: 1689: 1671: 1669: 1668: 1663: 1661: 1660: 1647: 1646: 1630: 1628: 1627: 1622: 1620: 1619: 1607: 1606: 1590: 1588: 1587: 1582: 1580: 1579: 1567: 1566: 1547: 1545: 1544: 1539: 1531: 1530: 1524: 1523: 1513: 1501: 1500: 1488: 1468: 1467: 1465: 1464: 1459: 1438: 1436: 1435: 1430: 1428: 1427: 1407: 1405: 1404: 1399: 1397: 1396: 1384: 1367: 1365: 1364: 1359: 1354: 1353: 1338: 1337: 1311: 1309: 1308: 1303: 1287: 1285: 1284: 1279: 1274: 1273: 1258: 1257: 1234: 1232: 1231: 1226: 1202: 1200: 1199: 1194: 1192: 1191: 1176: 1175: 1160: 1159: 1138: 1136: 1135: 1130: 1127: 1126: 1110: 1108: 1107: 1102: 1099: 1098: 1076: 1074: 1073: 1068: 1050: 1048: 1047: 1042: 1040: 1039: 1027: 1026: 1014: 1013: 994: 992: 991: 986: 969: 967: 966: 961: 944: 943: 920: 918: 917: 912: 792: 790: 789: 784: 782: 781: 769: 753:, is denoted by 752: 750: 749: 744: 729: 727: 726: 721: 709: 707: 706: 701: 699: 698: 679:, or in general 633: 626: 619: 604:Operator algebra 590:Clifford algebra 526: 524: 523: 518: 513: 512: 500: 479: 477: 476: 471: 469: 468: 463: 442: 440: 439: 434: 432: 431: 426: 404:Ring of integers 398: 395:Integers modulo 346:Euclidean domain 234: 232: 231: 226: 224: 216: 211: 188: 186: 185: 180: 178: 82:Product of rings 68:Fractional ideal 27: 19: 18: 5357: 5356: 5352: 5351: 5350: 5348: 5347: 5346: 5327: 5326: 5325: 5320: 5274: 5244: 5211: 5188: 5179: 5136: 5120: 5071: 5061: 5048: 5031: 4980: 4918: 4887:Initial objects 4873: 4819: 4712: 4701: 4699:Category theory 4696: 4627: 4622: 4621: 4614: 4598: 4594: 4589: 4577: 4568: 4535: 4534: 4532: 4529: 4528: 4504: 4503: 4495: 4493: 4490: 4489: 4469: 4468: 4460: 4458: 4455: 4454: 4437: 4436: 4434: 4431: 4430: 4409: 4408: 4406: 4403: 4402: 4385: 4384: 4382: 4379: 4378: 4361: 4360: 4358: 4355: 4354: 4333: 4332: 4330: 4327: 4326: 4309: 4308: 4306: 4303: 4302: 4282: 4281: 4272: 4271: 4269: 4266: 4265: 4237: 4236: 4227: 4226: 4224: 4221: 4220: 4201: 4198: 4197: 4175: 4172: 4171: 4147: 4144: 4143: 4127: 4124: 4123: 4106: 4105: 4103: 4100: 4099: 4068: 4065: 4064: 4043: 4042: 4040: 4037: 4036: 4033: 4005: 4001: 3988: 3979: 3975: 3962: 3953: 3949: 3936: 3928: 3925: 3924: 3901: 3897: 3888: 3884: 3875: 3871: 3863: 3860: 3859: 3819: 3815: 3801: 3788: 3770: 3766: 3753: 3739: 3737: 3734: 3733: 3723: 3683: 3674: 3653: 3628: 3601: 3573:if and only if 3506: 3503: 3502: 3486: 3483: 3482: 3455: 3451: 3443: 3441: 3438: 3437: 3418: 3415: 3414: 3394: 3391: 3390: 3374: 3362: 3358: 3353: 3348: 3340: 3334: 3330: 3325: 3320: 3318: 3315: 3314: 3298: 3292: 3288: 3283: 3278: 3276: 3273: 3272: 3205:, consider the 3172: 3168: 3159: 3155: 3153: 3150: 3149: 3132: 3128: 3126: 3123: 3122: 3106: 3103: 3102: 3083: 3080: 3079: 3040: 3036: 3031: 3028: 3027: 3007: 3004: 3003: 2986: 2982: 2980: 2977: 2976: 2972: 2929: 2925: 2923: 2920: 2919: 2896: 2892: 2883: 2879: 2874: 2871: 2870: 2850: 2846: 2833: 2825: 2822: 2821: 2800: 2772: 2768: 2759: 2755: 2747: 2744: 2743: 2715: 2712: 2711: 2691: 2687: 2676: 2673: 2672: 2652: 2648: 2637: 2634: 2633: 2613: 2609: 2598: 2595: 2594: 2568: 2564: 2555: 2551: 2546: 2543: 2542: 2520: 2517: 2516: 2496: 2492: 2483: 2479: 2470: 2466: 2464: 2461: 2460: 2438: 2435: 2434: 2411: 2407: 2398: 2394: 2392: 2389: 2388: 2371: 2370: 2368: 2365: 2364: 2347: 2344: 2343: 2323: 2319: 2308: 2305: 2304: 2283: 2282: 2280: 2277: 2276: 2253: 2249: 2240: 2236: 2231: 2228: 2227: 2206: 2205: 2203: 2200: 2199: 2193: 2171: 2167: 2154: 2145: 2141: 2132: 2128: 2126: 2123: 2122: 2105: 2101: 2088: 2086: 2083: 2082: 2059: 2055: 2046: 2042: 2037: 2034: 2033: 2015: 2011: 1998: 1996: 1993: 1992: 1975: 1971: 1958: 1949: 1945: 1936: 1932: 1930: 1927: 1926: 1898: 1895: 1894: 1874: 1870: 1858: 1854: 1844: 1840: 1838: 1835: 1834: 1809: 1805: 1793: 1789: 1777: 1773: 1761: 1757: 1755: 1752: 1751: 1729: 1726: 1725: 1703: 1700: 1699: 1677: 1674: 1673: 1656: 1652: 1642: 1638: 1636: 1633: 1632: 1615: 1611: 1602: 1598: 1596: 1593: 1592: 1575: 1571: 1562: 1558: 1556: 1553: 1552: 1526: 1525: 1519: 1515: 1509: 1496: 1492: 1479: 1477: 1474: 1473: 1452: 1449: 1448: 1444: 1423: 1419: 1417: 1414: 1413: 1392: 1388: 1375: 1373: 1370: 1369: 1346: 1342: 1333: 1329: 1324: 1321: 1320: 1297: 1294: 1293: 1266: 1262: 1253: 1249: 1244: 1241: 1240: 1208: 1205: 1204: 1184: 1180: 1168: 1164: 1152: 1148: 1146: 1143: 1142: 1122: 1118: 1116: 1113: 1112: 1091: 1087: 1085: 1082: 1081: 1056: 1053: 1052: 1035: 1031: 1022: 1018: 1006: 1002: 1000: 997: 996: 979: 976: 975: 939: 935: 930: 927: 926: 894: 891: 890: 846: 822: 802:category theory 777: 773: 760: 758: 755: 754: 738: 735: 734: 715: 712: 711: 694: 690: 688: 685: 684: 637: 608: 607: 540: 530: 529: 508: 504: 496: 494: 491: 490: 464: 459: 458: 456: 453: 452: 427: 422: 421: 419: 416: 415: 396: 366:Polynomial ring 316:Integral domain 305: 295: 294: 220: 212: 207: 199: 196: 195: 174: 172: 169: 168: 154:Involutive ring 39: 28: 22: 17: 12: 11: 5: 5355: 5345: 5344: 5339: 5322: 5321: 5319: 5318: 5308: 5298: 5287: 5284: 5283: 5280: 5279: 5276: 5275: 5273: 5272: 5267: 5262: 5248: 5242: 5237: 5232: 5226: 5224: 5217: 5216: 5213: 5212: 5210: 5209: 5204: 5193: 5191: 5186: 5181: 5180: 5178: 5177: 5172: 5167: 5162: 5157: 5152: 5141: 5139: 5134: 5126: 5122: 5121: 5119: 5114: 5112:String diagram 5109: 5104: 5102:Model category 5099: 5094: 5089: 5084: 5079: 5077: 5070: 5069: 5066: 5063: 5062: 5050: 5049: 5042: 5040: 5037: 5036: 5033: 5032: 5030: 5029: 5024: 5022:Comma category 5019: 5014: 5009: 5004: 4999: 4994: 4988: 4986: 4982: 4981: 4979: 4978: 4968: 4958: 4956:Abelian groups 4953: 4948: 4943: 4938: 4932: 4930: 4924: 4923: 4920: 4919: 4917: 4916: 4911: 4906: 4905: 4904: 4894: 4889: 4883: 4881: 4875: 4874: 4872: 4871: 4866: 4861: 4860: 4859: 4849: 4844: 4838: 4836: 4827: 4821: 4820: 4818: 4817: 4812: 4807: 4802: 4797: 4792: 4787: 4782: 4777: 4772: 4767: 4762: 4761: 4760: 4755: 4750: 4745: 4740: 4735: 4724: 4722: 4714: 4713: 4703: 4702: 4695: 4694: 4687: 4680: 4672: 4666: 4665: 4647: 4626: 4623: 4620: 4619: 4612: 4591: 4590: 4588: 4585: 4584: 4583: 4576: 4573: 4567: 4564: 4538: 4512: 4507: 4502: 4477: 4472: 4467: 4440: 4412: 4388: 4364: 4336: 4312: 4285: 4280: 4275: 4240: 4235: 4230: 4205: 4185: 4182: 4179: 4169:if and only if 4157: 4154: 4151: 4131: 4109: 4097:small category 4084: 4081: 4078: 4075: 4072: 4046: 4032: 4029: 4016: 4013: 4008: 4004: 4000: 3995: 3992: 3987: 3982: 3978: 3974: 3969: 3966: 3961: 3956: 3952: 3948: 3943: 3940: 3935: 3932: 3912: 3909: 3904: 3900: 3896: 3891: 3887: 3883: 3878: 3874: 3870: 3867: 3848: 3847: 3836: 3833: 3830: 3827: 3822: 3818: 3814: 3810: 3807: 3804: 3800: 3795: 3792: 3787: 3784: 3781: 3778: 3773: 3769: 3765: 3760: 3757: 3752: 3748: 3745: 3742: 3727:inverse limits 3722: 3719: 3718: 3717: 3710: 3707:final topology 3699: 3679: 3670: 3649: 3624: 3593: 3553:. Fix a point 3532: 3516: 3513: 3510: 3490: 3475: 3463: 3458: 3454: 3450: 3446: 3422: 3411:roots of unity 3398: 3377: 3371: 3368: 3365: 3361: 3356: 3351: 3347: 3343: 3337: 3333: 3328: 3323: 3301: 3295: 3291: 3286: 3281: 3258: 3195: 3183: 3180: 3175: 3171: 3167: 3162: 3158: 3135: 3131: 3110: 3087: 3076: 3065: 3043: 3039: 3035: 3011: 2989: 2985: 2971: 2968: 2932: 2928: 2907: 2902: 2899: 2895: 2891: 2886: 2882: 2878: 2867: 2866: 2853: 2849: 2845: 2840: 2837: 2832: 2829: 2794: 2775: 2771: 2767: 2762: 2758: 2754: 2751: 2731: 2728: 2725: 2722: 2719: 2699: 2694: 2690: 2686: 2683: 2680: 2660: 2655: 2651: 2647: 2644: 2641: 2621: 2616: 2612: 2608: 2605: 2602: 2579: 2574: 2571: 2567: 2563: 2558: 2554: 2550: 2530: 2527: 2524: 2502: 2499: 2495: 2491: 2486: 2482: 2478: 2473: 2469: 2448: 2445: 2442: 2422: 2419: 2414: 2410: 2406: 2401: 2397: 2374: 2351: 2331: 2326: 2322: 2318: 2315: 2312: 2286: 2264: 2259: 2256: 2252: 2248: 2243: 2239: 2235: 2222:by means of a 2209: 2192: 2189: 2174: 2170: 2166: 2161: 2158: 2153: 2148: 2144: 2140: 2135: 2131: 2108: 2104: 2100: 2095: 2092: 2070: 2065: 2062: 2058: 2054: 2049: 2045: 2041: 2018: 2014: 2010: 2005: 2002: 1978: 1974: 1970: 1965: 1962: 1957: 1952: 1948: 1944: 1939: 1935: 1908: 1905: 1902: 1882: 1877: 1873: 1869: 1864: 1861: 1857: 1852: 1847: 1843: 1817: 1812: 1808: 1804: 1799: 1796: 1792: 1788: 1785: 1780: 1776: 1772: 1767: 1764: 1760: 1739: 1736: 1733: 1713: 1710: 1707: 1687: 1684: 1681: 1659: 1655: 1650: 1645: 1641: 1618: 1614: 1610: 1605: 1601: 1578: 1574: 1570: 1565: 1561: 1549: 1548: 1537: 1534: 1529: 1522: 1518: 1512: 1508: 1504: 1499: 1495: 1491: 1486: 1483: 1456: 1426: 1422: 1410:disjoint union 1395: 1391: 1387: 1382: 1379: 1368:is denoted by 1357: 1352: 1349: 1345: 1341: 1336: 1332: 1328: 1301: 1277: 1272: 1269: 1265: 1261: 1256: 1252: 1248: 1239:Then the pair 1237: 1236: 1224: 1221: 1218: 1215: 1212: 1190: 1187: 1183: 1179: 1174: 1171: 1167: 1163: 1158: 1155: 1151: 1140: 1125: 1121: 1097: 1094: 1090: 1066: 1063: 1060: 1038: 1034: 1030: 1025: 1021: 1017: 1012: 1009: 1005: 983: 959: 956: 953: 950: 947: 942: 938: 934: 910: 907: 904: 901: 898: 872:(over a fixed 845: 842: 821: 818: 810:inverse limits 780: 776: 772: 767: 764: 742: 719: 697: 693: 639: 638: 636: 635: 628: 621: 613: 610: 609: 601: 600: 572: 571: 565: 559: 553: 541: 536: 535: 532: 531: 528: 527: 516: 511: 507: 503: 499: 480: 467: 462: 443: 430: 425: 413:-adic integers 406: 400: 391: 377: 376: 375: 374: 368: 362: 361: 360: 348: 342: 336: 330: 324: 306: 301: 300: 297: 296: 293: 292: 291: 290: 278: 277: 276: 270: 258: 257: 256: 238: 237: 236: 235: 223: 219: 215: 210: 206: 203: 189: 177: 156: 150: 144: 138: 124: 123: 117: 111: 97: 96: 90: 84: 78: 77: 76: 70: 58: 52: 40: 38:Basic concepts 37: 36: 33: 32: 15: 9: 6: 4: 3: 2: 5354: 5343: 5340: 5338: 5335: 5334: 5332: 5317: 5309: 5307: 5299: 5297: 5289: 5288: 5285: 5271: 5268: 5266: 5263: 5261: 5257: 5253: 5249: 5247: 5245: 5238: 5236: 5233: 5231: 5228: 5227: 5225: 5222: 5218: 5208: 5205: 5202: 5198: 5195: 5194: 5192: 5190: 5182: 5176: 5173: 5171: 5168: 5166: 5163: 5161: 5160:Tetracategory 5158: 5156: 5153: 5150: 5149:pseudofunctor 5146: 5143: 5142: 5140: 5138: 5130: 5127: 5123: 5118: 5115: 5113: 5110: 5108: 5105: 5103: 5100: 5098: 5095: 5093: 5090: 5088: 5085: 5083: 5080: 5078: 5074: 5068: 5067: 5064: 5060: 5055: 5051: 5046: 5028: 5025: 5023: 5020: 5018: 5015: 5013: 5010: 5008: 5005: 5003: 5000: 4998: 4995: 4993: 4992:Free category 4990: 4989: 4987: 4983: 4976: 4975:Vector spaces 4972: 4969: 4966: 4962: 4959: 4957: 4954: 4952: 4949: 4947: 4944: 4942: 4939: 4937: 4934: 4933: 4931: 4929: 4925: 4915: 4912: 4910: 4907: 4903: 4900: 4899: 4898: 4895: 4893: 4890: 4888: 4885: 4884: 4882: 4880: 4876: 4870: 4869:Inverse limit 4867: 4865: 4862: 4858: 4855: 4854: 4853: 4850: 4848: 4845: 4843: 4840: 4839: 4837: 4835: 4831: 4828: 4826: 4822: 4816: 4813: 4811: 4808: 4806: 4803: 4801: 4798: 4796: 4795:Kan extension 4793: 4791: 4788: 4786: 4783: 4781: 4778: 4776: 4773: 4771: 4768: 4766: 4763: 4759: 4756: 4754: 4751: 4749: 4746: 4744: 4741: 4739: 4736: 4734: 4731: 4730: 4729: 4726: 4725: 4723: 4719: 4715: 4708: 4704: 4700: 4693: 4688: 4686: 4681: 4679: 4674: 4673: 4670: 4662: 4658: 4657: 4652: 4648: 4645: 4641: 4637: 4633: 4629: 4628: 4615: 4613:9780521422611 4609: 4605: 4604: 4596: 4592: 4582: 4579: 4578: 4572: 4563: 4561: 4560:inverse limit 4557: 4552: 4526: 4428: 4351: 4301: 4263: 4258: 4256: 4219: 4203: 4183: 4180: 4177: 4170: 4155: 4149: 4129: 4098: 4079: 4076: 4073: 4062: 4028: 4014: 4006: 4002: 3998: 3993: 3990: 3980: 3976: 3972: 3967: 3964: 3954: 3950: 3946: 3941: 3938: 3930: 3910: 3902: 3898: 3889: 3885: 3876: 3872: 3865: 3857: 3856:exact functor 3853: 3834: 3828: 3825: 3820: 3816: 3798: 3793: 3790: 3785: 3779: 3776: 3771: 3767: 3763: 3758: 3755: 3732: 3731: 3730: 3728: 3715: 3711: 3708: 3704: 3700: 3697: 3693: 3689: 3688: 3682: 3678: 3675:of the stalk 3673: 3669: 3665: 3661: 3657: 3652: 3648: 3644: 3640: 3636: 3632: 3627: 3623: 3619: 3615: 3611: 3610: 3605: 3600: 3596: 3592: 3588: 3584: 3580: 3576: 3572: 3568: 3564: 3560: 3556: 3552: 3549: 3545: 3541: 3537: 3533: 3530: 3514: 3511: 3508: 3488: 3480: 3476: 3452: 3436: 3420: 3412: 3396: 3369: 3366: 3363: 3359: 3354: 3335: 3331: 3326: 3293: 3289: 3284: 3271: 3270:factor groups 3267: 3263: 3259: 3256: 3252: 3248: 3244: 3240: 3236: 3232: 3228: 3224: 3220: 3216: 3212: 3208: 3204: 3200: 3196: 3181: 3173: 3169: 3165: 3160: 3156: 3133: 3129: 3108: 3101: 3085: 3077: 3074: 3070: 3069:weak topology 3066: 3063: 3059: 3041: 3037: 3033: 3025: 3009: 2987: 2983: 2974: 2973: 2967: 2965: 2961: 2958: 2955: 2951: 2946: 2930: 2926: 2900: 2897: 2893: 2889: 2884: 2880: 2851: 2847: 2843: 2838: 2835: 2830: 2827: 2820: 2819: 2818: 2815: 2813: 2809: 2805: 2798: 2793: 2791: 2773: 2769: 2765: 2760: 2756: 2752: 2749: 2729: 2723: 2720: 2717: 2692: 2688: 2684: 2681: 2653: 2649: 2645: 2642: 2614: 2610: 2606: 2603: 2593: 2572: 2569: 2565: 2561: 2556: 2552: 2528: 2525: 2522: 2500: 2497: 2493: 2489: 2484: 2480: 2476: 2471: 2467: 2446: 2443: 2440: 2420: 2412: 2408: 2404: 2399: 2395: 2349: 2324: 2320: 2316: 2313: 2302: 2257: 2254: 2250: 2246: 2241: 2237: 2225: 2198: 2188: 2172: 2168: 2164: 2159: 2156: 2146: 2142: 2138: 2133: 2129: 2106: 2102: 2098: 2093: 2090: 2063: 2060: 2056: 2052: 2047: 2043: 2016: 2012: 2008: 2003: 2000: 1976: 1972: 1968: 1963: 1960: 1950: 1946: 1942: 1937: 1933: 1925: 1920: 1906: 1903: 1900: 1875: 1871: 1862: 1859: 1855: 1850: 1845: 1841: 1832: 1831:inverse limit 1810: 1806: 1797: 1794: 1790: 1786: 1778: 1774: 1765: 1762: 1758: 1737: 1734: 1731: 1711: 1708: 1705: 1685: 1682: 1679: 1657: 1653: 1648: 1643: 1639: 1616: 1612: 1608: 1603: 1599: 1576: 1572: 1568: 1563: 1559: 1535: 1532: 1520: 1516: 1510: 1506: 1502: 1497: 1493: 1489: 1484: 1481: 1472: 1471: 1470: 1454: 1447: 1442: 1424: 1420: 1411: 1393: 1389: 1385: 1380: 1377: 1350: 1347: 1343: 1339: 1334: 1330: 1318: 1313: 1299: 1291: 1290:direct system 1270: 1267: 1263: 1259: 1254: 1250: 1222: 1219: 1216: 1213: 1210: 1188: 1185: 1181: 1177: 1172: 1169: 1165: 1161: 1156: 1153: 1149: 1141: 1123: 1119: 1095: 1092: 1088: 1080: 1079: 1078: 1064: 1061: 1058: 1036: 1032: 1023: 1019: 1015: 1010: 1007: 1003: 981: 973: 954: 951: 948: 945: 940: 936: 924: 905: 902: 899: 887: 885: 881: 880: 879:homomorphisms 875: 871: 867: 863: 859: 855: 851: 841: 839: 835: 831: 827: 817: 815: 811: 807: 803: 799: 794: 778: 774: 770: 765: 762: 740: 733: 717: 695: 691: 682: 678: 674: 670: 669:homomorphisms 666: 662: 661:vector spaces 658: 654: 650: 646: 634: 629: 627: 622: 620: 615: 614: 612: 611: 606: 605: 599: 595: 594: 593: 592: 591: 586: 585: 584: 579: 578: 577: 570: 566: 564: 560: 558: 554: 552: 551:Division ring 548: 547: 546: 545: 539: 534: 533: 505: 489: 487: 481: 465: 451: 450:-adic numbers 449: 444: 428: 414: 412: 407: 405: 401: 399: 392: 390: 386: 385: 384: 383: 382: 373: 369: 367: 363: 359: 355: 354: 353: 349: 347: 343: 341: 337: 335: 331: 329: 325: 323: 319: 318: 317: 313: 312: 311: 310: 304: 299: 298: 289: 285: 284: 283: 279: 275: 271: 269: 265: 264: 263: 259: 255: 251: 250: 249: 245: 244: 243: 242: 217: 213: 204: 201: 194: 193:Terminal ring 190: 167: 163: 162: 161: 157: 155: 151: 149: 145: 143: 139: 137: 133: 132: 131: 130: 129: 122: 118: 116: 112: 110: 106: 105: 104: 103: 102: 95: 91: 89: 85: 83: 79: 75: 71: 69: 65: 64: 63: 62:Quotient ring 59: 57: 53: 51: 47: 46: 45: 44: 35: 34: 31: 26:→ Ring theory 25: 21: 20: 5240: 5221:Categorified 5125:n-categories 5076:Key concepts 4914:Direct limit 4913: 4897:Coequalizers 4815:Yoneda lemma 4721:Key concepts 4711:Key concepts 4654: 4635: 4602: 4595: 4569: 4553: 4352: 4259: 4034: 3849: 3724: 3695: 3691: 3685: 3680: 3676: 3671: 3667: 3663: 3659: 3655: 3650: 3646: 3642: 3638: 3634: 3630: 3625: 3621: 3617: 3613: 3607: 3603: 3598: 3594: 3590: 3586: 3582: 3578: 3574: 3570: 3566: 3562: 3558: 3554: 3550: 3539: 3535: 3435:Prüfer group 3266:prime number 3261: 3250: 3246: 3242: 3238: 3234: 3230: 3226: 3222: 3218: 3214: 3210: 3202: 3198: 2963: 2959: 2953: 2949: 2947: 2868: 2816: 2811: 2807: 2801: 2789: 2591: 2300: 2194: 1923: 1921: 1550: 1317:direct limit 1316: 1314: 1289: 1288:is called a 1238: 923:directed set 888: 877: 847: 823: 795: 732:directed set 649:direct limit 648: 642: 602: 588: 587: 583:Free algebra 581: 580: 574: 573: 542: 485: 447: 410: 379: 378: 358:Finite field 307: 254:Finite field 240: 239: 166:Initial ring 126: 125: 99: 98: 41: 5189:-categories 5165:Kan complex 5155:Tricategory 5137:-categories 5027:Subcategory 4785:Exponential 4753:Preadditive 4748:Pre-abelian 4566:Terminology 4525:ind-objects 4523:are called 3684:called the 3666:an element 2957:isomorphism 645:mathematics 563:Simple ring 274:Jordan ring 148:Graded ring 30:Ring theory 5331:Categories 5207:3-category 5197:2-category 5170:∞-groupoid 5145:Bicategory 4892:Coproducts 4852:Equalizers 4758:Bicategory 4625:References 3721:Properties 3714:ind-scheme 3620:, denoted 3073:CW complex 2802:will then 2742:such that 2515:whenever 2459:such that 2303:is a pair 1750:such that 1443:a certain 856:, such as 569:Commutator 328:GCD domain 5256:Symmetric 5201:2-functor 4941:Relations 4864:Pullbacks 4279:→ 4234:→ 4181:≤ 4153:→ 4083:⟩ 4080:≤ 4071:⟨ 4012:→ 3999:⁡ 3994:→ 3986:→ 3973:⁡ 3968:→ 3960:→ 3947:⁡ 3942:→ 3934:→ 3908:→ 3895:→ 3882:→ 3869:→ 3799:⁡ 3794:← 3764:⁡ 3759:→ 3577:contains 3457:∞ 3346:→ 3179:→ 3157:ϕ 3058:subgroups 3034:⋃ 3002:of a set 2927:ϕ 2906:⟩ 2877:⟨ 2844:⁡ 2839:→ 2788:for each 2770:ψ 2757:ϕ 2753:∘ 2727:→ 2721:: 2698:⟩ 2689:ψ 2679:⟨ 2659:⟩ 2650:ϕ 2640:⟨ 2620:⟩ 2611:ϕ 2601:⟨ 2578:⟩ 2549:⟨ 2526:≤ 2490:∘ 2481:ϕ 2468:ϕ 2444:∈ 2418:→ 2405:: 2396:ϕ 2330:⟩ 2321:ϕ 2311:⟨ 2263:⟩ 2234:⟨ 2165:⁡ 2160:→ 2152:→ 2139:: 2130:ϕ 2099:⁡ 2094:→ 2069:⟩ 2040:⟨ 2009:⁡ 2004:→ 1969:⁡ 1964:→ 1956:→ 1943:: 1934:ϕ 1904:≤ 1893:whenever 1851:∼ 1735:≤ 1709:≤ 1683:∈ 1649:∼ 1609:∈ 1569:∈ 1551:Here, if 1533:∼ 1507:⨆ 1490:⁡ 1485:→ 1455:∼ 1386:⁡ 1381:→ 1356:⟩ 1327:⟨ 1276:⟩ 1247:⟨ 1220:≤ 1214:≤ 1178:∘ 1062:≤ 1029:→ 1016:: 952:∈ 909:⟩ 906:≤ 897:⟨ 886:, etc.). 771:⁡ 766:→ 681:morphisms 510:∞ 288:Semifield 5316:Glossary 5296:Category 5270:n-monoid 5223:concepts 4879:Colimits 4847:Products 4800:Morphism 4743:Concrete 4738:Additive 4728:Category 4653:(1998), 4634:(1968), 4575:See also 4061:functors 3602:) where 3542:-valued 3062:subrings 2970:Examples 2806:for all 2197:category 1203:for all 870:algebras 838:category 710:, where 665:category 282:Semiring 268:Lie ring 50:Subrings 5306:Outline 5265:n-group 5230:2-group 5185:Strict 5175:∞-topos 4971:Modules 4909:Pushout 4857:Kernels 4790:Functor 4733:Abelian 4644:0237342 4298:from a 4255:colimit 3852:modules 3229:) → GL( 3022:can be 2804:commute 1631:, then 1412:of the 972:indexed 866:modules 834:modules 798:colimit 484:Prüfer 86:•  5252:Traced 5235:2-ring 4965:Fields 4951:Groups 4946:Magmas 4834:Limits 4642:  4610:  4253:. The 3854:is an 2954:unique 2342:where 2301:target 2226:. Let 1441:modulo 925:. Let 858:groups 830:groups 814:limits 653:groups 136:Module 109:Kernel 5246:-ring 5133:Weak 5117:Topos 4961:Rings 4587:Notes 3662:over 3609:stalk 3546:on a 3544:sheaf 3538:be a 3264:be a 3071:of a 2590:is a 1698:with 1292:over 1139:, and 995:and 921:be a 874:field 862:rings 828:like 657:rings 488:-ring 352:Field 248:Field 56:Ideal 43:Rings 4936:Sets 4608:ISBN 4554:The 4551:. 4527:of 3729:via 3687:germ 3645:) → 3534:Let 3260:Let 3197:Let 3078:Let 3067:The 2962:′ → 2387:and 1724:and 1591:and 1315:The 889:Let 850:sets 832:and 806:dual 647:, a 4780:End 4770:CCC 4497:Ind 4462:Ind 3991:lim 3965:lim 3939:lim 3791:lim 3756:lim 3712:An 3694:at 3690:of 3658:of 3633:of 3616:at 3612:of 3589:), 3557:in 3481:in 3233:+1; 3227:n;K 3211:n;K 3209:GL( 2836:lim 2814:. 2157:lim 2091:lim 2001:lim 1961:lim 1482:lim 1439:'s 1378:lim 974:by 808:to 800:in 763:lim 643:In 5333:: 5258:) 5254:)( 4659:, 4640:MR 4027:. 3569:≤ 3217:x 2810:, 2187:. 1919:. 1469:: 1312:. 864:, 860:, 840:. 675:, 659:, 655:, 596:• 567:• 561:• 555:• 549:• 482:• 445:• 408:• 402:• 393:• 387:• 370:• 364:• 356:• 350:• 344:• 338:• 332:• 326:• 320:• 314:• 286:• 280:• 272:• 266:• 260:• 252:• 246:• 191:• 164:• 158:• 152:• 146:• 140:• 134:• 119:• 113:• 107:• 92:• 80:• 72:• 66:• 60:• 54:• 48:• 5250:( 5243:n 5241:E 5203:) 5199:( 5187:n 5151:) 5147:( 5135:n 4977:) 4973:( 4967:) 4963:( 4691:e 4684:t 4677:v 4616:. 4537:C 4511:) 4506:C 4501:( 4476:) 4471:C 4466:( 4439:C 4411:C 4387:C 4363:C 4335:C 4311:J 4284:C 4274:J 4239:C 4229:I 4204:I 4184:j 4178:i 4156:j 4150:i 4130:I 4108:I 4077:, 4074:I 4045:C 4015:0 4007:i 4003:C 3981:i 3977:B 3955:i 3951:A 3931:0 3911:0 3903:i 3899:C 3890:i 3886:B 3877:i 3873:A 3866:0 3835:. 3832:) 3829:Y 3826:, 3821:i 3817:X 3813:( 3809:m 3806:o 3803:H 3786:= 3783:) 3780:Y 3777:, 3772:i 3768:X 3751:( 3747:m 3744:o 3741:H 3698:. 3696:x 3692:s 3681:x 3677:F 3672:x 3668:s 3664:U 3660:F 3656:s 3651:x 3647:F 3643:U 3641:( 3639:F 3635:x 3631:U 3626:x 3622:F 3618:x 3614:F 3604:r 3599:V 3597:, 3595:U 3591:r 3587:U 3585:( 3583:F 3579:V 3575:U 3571:V 3567:U 3563:x 3559:X 3555:x 3551:X 3540:C 3536:F 3531:. 3515:1 3512:+ 3509:n 3489:n 3474:. 3462:) 3453:p 3449:( 3445:Z 3421:p 3397:p 3376:Z 3370:1 3367:+ 3364:n 3360:p 3355:/ 3350:Z 3342:Z 3336:n 3332:p 3327:/ 3322:Z 3300:Z 3294:n 3290:p 3285:/ 3280:Z 3262:p 3257:. 3251:K 3247:K 3243:K 3239:K 3235:K 3231:n 3223:K 3219:n 3215:n 3203:n 3199:K 3182:X 3174:m 3170:X 3166:: 3161:m 3134:m 3130:X 3109:m 3086:X 3042:i 3038:M 3010:M 2988:i 2984:M 2964:X 2960:X 2950:X 2931:i 2901:j 2898:i 2894:f 2890:, 2885:i 2881:X 2852:i 2848:X 2831:= 2828:X 2812:j 2808:i 2790:i 2774:i 2766:= 2761:i 2750:u 2730:Y 2724:X 2718:u 2693:i 2685:, 2682:Y 2654:i 2646:, 2643:X 2615:i 2607:, 2604:X 2573:j 2570:i 2566:f 2562:, 2557:i 2553:X 2529:j 2523:i 2501:j 2498:i 2494:f 2485:j 2477:= 2472:i 2447:I 2441:i 2421:X 2413:i 2409:X 2400:i 2373:C 2350:X 2325:i 2317:, 2314:X 2285:C 2258:j 2255:i 2251:f 2247:, 2242:i 2238:X 2208:C 2173:i 2169:A 2147:j 2143:A 2134:j 2107:i 2103:A 2064:j 2061:i 2057:f 2053:, 2048:i 2044:A 2017:i 2013:A 1977:i 1973:A 1951:j 1947:A 1938:j 1907:j 1901:i 1881:) 1876:i 1872:x 1868:( 1863:j 1860:i 1856:f 1846:i 1842:x 1816:) 1811:j 1807:x 1803:( 1798:k 1795:j 1791:f 1787:= 1784:) 1779:i 1775:x 1771:( 1766:k 1763:i 1759:f 1738:k 1732:j 1712:k 1706:i 1686:I 1680:k 1658:j 1654:x 1644:i 1640:x 1617:j 1613:A 1604:j 1600:x 1577:i 1573:A 1564:i 1560:x 1536:. 1528:/ 1521:i 1517:A 1511:i 1503:= 1498:i 1494:A 1425:i 1421:A 1394:i 1390:A 1351:j 1348:i 1344:f 1340:, 1335:i 1331:A 1300:I 1271:j 1268:i 1264:f 1260:, 1255:i 1251:A 1235:. 1223:k 1217:j 1211:i 1189:j 1186:i 1182:f 1173:k 1170:j 1166:f 1162:= 1157:k 1154:i 1150:f 1124:i 1120:A 1096:i 1093:i 1089:f 1065:j 1059:i 1037:j 1033:A 1024:i 1020:A 1011:j 1008:i 1004:f 982:I 958:} 955:I 949:i 946:: 941:i 937:A 933:{ 903:, 900:I 779:i 775:A 741:I 718:i 696:i 692:A 671:( 632:e 625:t 618:v 515:) 506:p 502:( 498:Z 486:p 466:p 461:Q 448:p 429:p 424:Z 411:p 397:n 222:Z 218:1 214:/ 209:Z 205:= 202:0 176:Z

Index

Algebraic structure
Ring theory
Rings
Subrings
Ideal
Quotient ring
Fractional ideal
Total ring of fractions
Product of rings
Free product of associative algebras
Tensor product of algebras
Ring homomorphisms
Kernel
Inner automorphism
Frobenius endomorphism
Algebraic structures
Module
Associative algebra
Graded ring
Involutive ring
Category of rings
Initial ring
Terminal ring
Field
Finite field
Non-associative ring
Lie ring
Jordan ring
Semiring
Semifield

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.