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Localizing subcategory

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is closed under arbitrary coproducts (a.k.a. direct sums). Hence the notion of a localizing subcategory is equivalent to the notion of a hereditary
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between abelian categories are Serre subcategories, and that one can build (for locally small
33: 712: 69: 29: 1158: 260: 813: 235: 1116: 957: 901: 840: 793: 769: 452: 191: 108: 1172: 862: 420: 416: 73: 25: 759:{\displaystyle S\colon {\mathcal {A}}/{\mathcal {C}}\rightarrow {\mathcal {A}}} 704:{\displaystyle T\colon {\mathcal {A}}\rightarrow {\mathcal {A}}/{\mathcal {C}}} 568:{\displaystyle T\colon {\mathcal {A}}\rightarrow {\mathcal {A}}/{\mathcal {C}}} 523:, is abelian, and comes with an exact functor (called the quotient functor) 157:{\displaystyle 0\rightarrow A'\rightarrow A\rightarrow A''\rightarrow 0} 1078:
implies that every Grothendieck category is the quotient category of a
790:, each localizing subcategory is closed under colimits. The functor 419:. The importance of this notion stems from the fact that kernels of 330:
is closed under subobjects, quotient objects and extensions.
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Abelian Categories with Applications to Rings and Modules
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is itself an abelian category, and the inclusion functor
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The Serre subcategory 1106:{\displaystyle \operatorname {Mod} (R)} 1165:; Academic Press, Inc.; out of print. 7: 1137:) modulo a localizing subcategory. 1071:are again Grothendieck categories. 14: 499:, which has the same objects as 1011:a localizing subcategory, then 987:is a Grothendieck category and 786:, as a left adjoint, preserves 1100: 1094: 1028:{\displaystyle {\mathcal {C}}} 1004:{\displaystyle {\mathcal {C}}} 980:{\displaystyle {\mathcal {A}}} 949:{\displaystyle {\mathcal {C}}} 925:{\displaystyle {\mathcal {C}}} 889:{\displaystyle {\mathcal {A}}} 746: 679: 648:{\displaystyle {\mathcal {C}}} 624:{\displaystyle {\mathcal {A}}} 592:{\displaystyle {\mathcal {C}}} 543: 516:{\displaystyle {\mathcal {A}}} 440:{\displaystyle {\mathcal {A}}} 395: 374:{\displaystyle {\mathcal {A}}} 350:{\displaystyle {\mathcal {C}}} 323:{\displaystyle {\mathcal {C}}} 299:{\displaystyle {\mathcal {C}}} 225:{\displaystyle {\mathcal {C}}} 181:{\displaystyle {\mathcal {A}}} 148: 137: 131: 120: 92:{\displaystyle {\mathcal {C}}} 61:{\displaystyle {\mathcal {A}}} 1: 932:is localizing if and only if 908:), then a Serre subcategory 232:if and only if the objects 1200: 1035:and the quotient category 24:form important classes of 861:. The section functor is 872:If the abelian category 659:if the quotient functor 603:Localizing subcategories 22:localizing subcategories 1076:Gabriel-Popescu theorem 333:Each Serre subcategory 1127: 1107: 1065: 1029: 1005: 981: 950: 926: 890: 851: 827: 804: 780: 760: 705: 649: 625: 593: 569: 517: 493: 441: 409: 375: 351: 324: 300: 276: 251: 226: 202: 182: 158: 107:), if for every short 93: 62: 1128: 1108: 1066: 1030: 1006: 982: 951: 927: 906:Grothendieck category 891: 852: 833:) is also called the 828: 805: 781: 761: 706: 650: 626: 594: 570: 518: 494: 442: 410: 376: 352: 325: 301: 277: 252: 227: 203: 183: 159: 94: 63: 1117: 1085: 1039: 1015: 991: 967: 936: 912: 876: 841: 835:localization functor 814: 794: 770: 718: 663: 635: 611: 579: 527: 503: 467: 427: 385: 361: 337: 310: 286: 261: 236: 212: 192: 168: 114: 79: 48: 1184:Homological algebra 275:{\displaystyle A''} 72:. A non-empty full 40:Serre subcategories 1147:Giraud subcategory 1123: 1103: 1061: 1025: 1001: 977: 946: 922: 886: 847: 826:{\displaystyle ST} 823: 800: 776: 756: 701: 645: 621: 589: 565: 513: 489: 437: 405: 371: 347: 320: 296: 272: 250:{\displaystyle A'} 247: 222: 198: 178: 154: 89: 58: 1126:{\displaystyle R} 904:(e.g. if it is a 850:{\displaystyle S} 803:{\displaystyle T} 779:{\displaystyle T} 451:(in the sense of 449:quotient category 201:{\displaystyle A} 105:dense subcategory 101:Serre subcategory 34:quotient category 1191: 1164: 1132: 1130: 1129: 1124: 1112: 1110: 1109: 1104: 1070: 1068: 1067: 1062: 1060: 1059: 1053: 1048: 1047: 1034: 1032: 1031: 1026: 1024: 1023: 1010: 1008: 1007: 1002: 1000: 999: 986: 984: 983: 978: 976: 975: 955: 953: 952: 947: 945: 944: 931: 929: 928: 923: 921: 920: 895: 893: 892: 887: 885: 884: 856: 854: 853: 848: 832: 830: 829: 824: 809: 807: 806: 801: 785: 783: 782: 777: 765: 763: 762: 757: 755: 754: 745: 744: 738: 733: 732: 710: 708: 707: 702: 700: 699: 693: 688: 687: 678: 677: 654: 652: 651: 646: 644: 643: 630: 628: 627: 622: 620: 619: 598: 596: 595: 590: 588: 587: 575:whose kernel is 574: 572: 571: 566: 564: 563: 557: 552: 551: 542: 541: 522: 520: 519: 514: 512: 511: 498: 496: 495: 490: 488: 487: 481: 476: 475: 446: 444: 443: 438: 436: 435: 414: 412: 411: 406: 404: 403: 394: 393: 380: 378: 377: 372: 370: 369: 356: 354: 353: 348: 346: 345: 329: 327: 326: 321: 319: 318: 305: 303: 302: 297: 295: 294: 281: 279: 278: 273: 271: 256: 254: 253: 248: 246: 231: 229: 228: 223: 221: 220: 207: 205: 204: 199: 187: 185: 184: 179: 177: 176: 163: 161: 160: 155: 147: 130: 98: 96: 95: 90: 88: 87: 70:abelian category 67: 65: 64: 59: 57: 56: 30:abelian category 16:In mathematics, 1199: 1198: 1194: 1193: 1192: 1190: 1189: 1188: 1179:Category theory 1169: 1168: 1162: 1159:Nicolae Popescu 1155: 1143: 1115: 1114: 1083: 1082: 1080:module category 1037: 1036: 1013: 1012: 989: 988: 965: 964: 934: 933: 910: 909: 902:injective hulls 874: 873: 859:section functor 839: 838: 812: 811: 792: 791: 768: 767: 716: 715: 661: 660: 633: 632: 609: 608: 605: 577: 576: 525: 524: 501: 500: 465: 464: 425: 424: 383: 382: 359: 358: 335: 334: 308: 307: 284: 283: 264: 259: 258: 239: 234: 233: 210: 209: 190: 189: 166: 165: 140: 123: 112: 111: 77: 76: 46: 45: 42: 12: 11: 5: 1197: 1195: 1187: 1186: 1181: 1171: 1170: 1167: 1166: 1154: 1151: 1150: 1149: 1142: 1139: 1122: 1102: 1099: 1096: 1093: 1090: 1058: 1052: 1046: 1022: 998: 974: 943: 919: 883: 867:fully faithful 846: 822: 819: 810:(or sometimes 799: 775: 753: 748: 743: 737: 731: 726: 723: 698: 692: 686: 681: 676: 671: 668: 642: 618: 604: 601: 586: 562: 556: 550: 545: 540: 535: 532: 510: 486: 480: 474: 434: 421:exact functors 402: 397: 392: 368: 344: 317: 293: 270: 267: 245: 242: 219: 197: 175: 153: 150: 146: 143: 139: 136: 133: 129: 126: 122: 119: 109:exact sequence 86: 55: 41: 38: 13: 10: 9: 6: 4: 3: 2: 1196: 1185: 1182: 1180: 1177: 1176: 1174: 1160: 1157: 1156: 1152: 1148: 1145: 1144: 1140: 1138: 1136: 1120: 1097: 1091: 1088: 1081: 1077: 1072: 1050: 961: 959: 958:torsion class 907: 903: 899: 870: 868: 864: 860: 844: 836: 820: 817: 797: 789: 773: 766:. Since then 735: 724: 721: 714: 713:right adjoint 690: 669: 666: 658: 602: 600: 554: 533: 530: 478: 462: 458: 454: 450: 422: 418: 331: 268: 265: 243: 240: 195: 151: 144: 141: 134: 127: 124: 117: 110: 106: 102: 75: 71: 39: 37: 35: 31: 27: 26:subcategories 23: 19: 1073: 962: 896:is moreover 871: 858: 834: 656: 606: 457:Grothendieck 332: 306:. In words: 104: 100: 99:is called a 43: 21: 17: 15: 1133:a suitable 188:the object 103:(or also a 74:subcategory 1173:Categories 1153:References 898:cocomplete 863:left-exact 657:localizing 655:is called 282:belong to 1092:⁡ 747:→ 725:: 680:→ 670:: 544:→ 534:: 396:→ 149:→ 138:→ 132:→ 121:→ 1161:; 1973; 1141:See also 900:and has 788:colimits 269:″ 244:′ 145:″ 128:′ 453:Gabriel 1113:(with 837:, and 711:has a 447:) the 208:is in 68:be an 28:of an 461:Serre 417:exact 18:Serre 1135:ring 1074:The 865:and 857:the 607:Let 257:and 44:Let 20:and 1089:Mod 963:If 415:is 357:of 164:in 1175:: 960:. 869:. 599:. 463:) 459:, 455:, 36:. 1121:R 1101:) 1098:R 1095:( 1057:C 1051:/ 1045:A 1021:C 997:C 973:A 942:C 918:C 882:A 845:S 821:T 818:S 798:T 774:T 752:A 742:C 736:/ 730:A 722:S 697:C 691:/ 685:A 675:A 667:T 641:C 617:A 585:C 561:C 555:/ 549:A 539:A 531:T 509:A 485:C 479:/ 473:A 433:A 401:A 391:C 367:A 343:C 316:C 292:C 266:A 241:A 218:C 196:A 174:A 152:0 142:A 135:A 125:A 118:0 85:C 54:A

Index

subcategories
abelian category
quotient category
abelian category
subcategory
exact sequence
exact
exact functors
quotient category
Gabriel
Grothendieck
Serre
right adjoint
colimits
left-exact
fully faithful
cocomplete
injective hulls
Grothendieck category
torsion class
Gabriel-Popescu theorem
module category
ring
Giraud subcategory
Nicolae Popescu
Categories
Category theory
Homological algebra

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