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Permutation representation

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1763: 1519: 1398: 1654: 576: 240: 290: 1405: 1284: 1546: 416: 1204: 1236: 963: 1086:. Now the character of this representation is defined as the trace of this permutation matrix. An element on the diagonal of a permutation matrix is 1 if the point in 1044: 1012: 911: 1160: 605: 862: 680: 1674: 1539: 1276: 1256: 1124: 1104: 1084: 1064: 983: 931: 882: 839: 819: 799: 779: 743: 723: 703: 653: 629: 523: 499: 475: 451: 378: 358: 334: 314: 190: 166: 142: 119: 76: 52: 1751: 1823: 1804: 1106:
is fixed, and 0 otherwise. So we can conclude that the trace of the permutation matrix is exactly equal to the number of fixed points of
17: 685:
This notion of a permutation representation can, of course, be composed with the previous one to represent an arbitrary abstract group
530: 198: 1514:{\displaystyle \chi ((123))=\operatorname {tr} ({\begin{bmatrix}0&1&0\\0&0&1\\1&0&0\end{bmatrix}})=0} 248: 1393:{\displaystyle \chi ((12))=\operatorname {tr} ({\begin{bmatrix}0&1&0\\1&0&0\\0&0&1\end{bmatrix}})=1} 1797: 1649:{\displaystyle \chi (1)=\operatorname {tr} ({\begin{bmatrix}1&0&0\\0&1&0\\0&0&1\end{bmatrix}})=3} 1752:
https://mathoverflow.net/questions/286393/how-do-i-know-if-an-irreducible-representation-is-a-permutation-representation
1732: 1705: 1833: 1790: 55: 1828: 422: 337: 746: 386: 1778: 1165: 842: 725:
as a permutation group and then maps each permutation to the corresponding matrix. Representing
1209: 936: 750: 1020: 988: 887: 1132: 584: 847: 658: 502: 83: 8: 632: 99: 32: 1659: 1524: 1261: 1241: 1109: 1089: 1069: 1049: 968: 916: 867: 824: 804: 784: 764: 728: 708: 688: 638: 614: 608: 508: 484: 460: 436: 363: 343: 319: 299: 175: 151: 145: 127: 104: 61: 37: 1728: 1701: 454: 293: 122: 1770: 1722: 1695: 1206:
the character of the permutation representation can be computed with the formula
169: 1774: 1817: 864:
of the permutation representation is exactly the number of fixed points of
79: 24: 1762: 756: 571:{\displaystyle \rho \colon G\to \operatorname {GL} _{n}(K)} 705:
as a group of permutation matrices. One first represents
235:{\displaystyle \rho \colon G\to \operatorname {Sym} (X).} 1700:. Springer Science & Business Media. pp. 5–6. 285:{\displaystyle \rho (G)\subset \operatorname {Sym} (X)} 1579: 1444: 1323: 89: 86:. The term also refers to the combination of the two. 54:
can refer to either of two closely related notions: a
1662: 1549: 1527: 1408: 1287: 1264: 1244: 1212: 1168: 1135: 1112: 1092: 1072: 1052: 1023: 991: 971: 939: 919: 890: 870: 850: 827: 807: 787: 767: 731: 711: 691: 661: 641: 617: 587: 533: 511: 487: 463: 439: 389: 366: 346: 322: 302: 251: 201: 178: 154: 130: 107: 64: 40: 1046:
with a matrix with basis defined by the elements of
428: 336:. A permutation representation is equivalent to an 1668: 1648: 1533: 1513: 1392: 1270: 1250: 1230: 1198: 1154: 1118: 1098: 1078: 1058: 1038: 1006: 977: 957: 925: 905: 876: 856: 833: 813: 793: 773: 737: 717: 697: 674: 647: 623: 599: 570: 517: 493: 469: 445: 410: 372: 352: 328: 308: 284: 234: 184: 160: 136: 113: 70: 46: 1815: 1694:Dixon, John D.; Mortimer, Brian (2012-12-06). 1798: 1693: 1193: 1175: 1017:This follows since, if we represent the map 757:Character of the permutation representation 745:as a permutation group acting on itself by 18:Permutation representation (disambiguation) 1805: 1791: 1727:. Springer Science & Business Media. 682:by permuting the standard basis vectors. 1720: 1824:Representation theory of finite groups 1816: 1757: 1721:Robinson, Derek J. S. (2012-12-06). 316:are represented as permutations of 90:Abstract permutation representation 13: 14: 1845: 1745: 429:Linear permutation representation 1761: 1724:A Course in the Theory of Groups 1066:we get a permutation matrix of 411:{\displaystyle G\times X\to X.} 1714: 1687: 1637: 1571: 1559: 1553: 1502: 1436: 1424: 1421: 1415: 1412: 1381: 1315: 1303: 1300: 1294: 1291: 1222: 1216: 1033: 1027: 1001: 995: 949: 943: 900: 894: 565: 559: 543: 399: 279: 273: 261: 255: 226: 220: 211: 1: 1680: 1777:. You can help Knowledge by 7: 1199:{\displaystyle X=\{1,2,3\}} 10: 1850: 1756: 479:permutation representation 96:permutation representation 29:permutation representation 15: 1231:{\displaystyle \chi (g)=} 958:{\displaystyle \chi (g)=} 1238:the number of points of 1039:{\displaystyle \rho (g)} 1007:{\displaystyle \rho (g)} 965:the number of points of 906:{\displaystyle \rho (g)} 31:of a (typically finite) 1155:{\displaystyle G=S_{3}} 1834:Abstract algebra stubs 1773:-related article is a 1670: 1650: 1535: 1515: 1394: 1272: 1252: 1232: 1200: 1156: 1120: 1100: 1080: 1060: 1040: 1008: 979: 959: 927: 907: 878: 858: 835: 815: 795: 775: 751:regular representation 739: 719: 699: 676: 649: 625: 601: 600:{\displaystyle g\in G} 572: 519: 495: 471: 447: 412: 374: 354: 330: 310: 286: 236: 186: 162: 138: 115: 72: 48: 1671: 1651: 1536: 1516: 1395: 1273: 1253: 1233: 1201: 1157: 1121: 1101: 1081: 1061: 1041: 1009: 980: 960: 928: 908: 879: 859: 857:{\displaystyle \chi } 836: 816: 796: 776: 740: 720: 700: 677: 675:{\displaystyle K^{n}} 650: 626: 607:to the corresponding 602: 573: 520: 503:linear representation 496: 472: 448: 425:for further details. 413: 375: 355: 331: 311: 287: 237: 187: 163: 139: 116: 73: 49: 1660: 1656:as every element of 1547: 1525: 1406: 1285: 1262: 1242: 1210: 1166: 1133: 1110: 1090: 1070: 1050: 1021: 989: 969: 937: 917: 888: 884:under the action of 868: 848: 825: 805: 785: 765: 729: 709: 689: 659: 639: 615: 585: 531: 509: 485: 461: 437: 387: 364: 344: 320: 300: 296:and the elements of 249: 199: 176: 152: 128: 105: 84:permutation matrices 62: 38: 16:For other uses, see 421:See the article on 82:, or as a group of 1829:Permutation groups 1697:Permutation Groups 1666: 1646: 1631: 1531: 1521:as no elements of 1511: 1496: 1400:as only 3 is fixed 1390: 1375: 1268: 1248: 1228: 1196: 1152: 1116: 1096: 1076: 1056: 1036: 1004: 975: 955: 923: 903: 874: 854: 831: 821:acting on the set 811: 791: 771: 749:, one obtains the 735: 715: 695: 672: 645: 621: 609:permutation matrix 597: 568: 515: 491: 467: 443: 408: 370: 350: 326: 306: 282: 232: 182: 158: 134: 111: 68: 44: 1786: 1785: 1669:{\displaystyle X} 1534:{\displaystyle X} 1271:{\displaystyle g} 1251:{\displaystyle X} 1119:{\displaystyle X} 1099:{\displaystyle X} 1079:{\displaystyle X} 1059:{\displaystyle X} 978:{\displaystyle X} 926:{\displaystyle X} 877:{\displaystyle X} 834:{\displaystyle X} 814:{\displaystyle G} 794:{\displaystyle X} 781:and a finite set 774:{\displaystyle G} 738:{\displaystyle G} 718:{\displaystyle G} 698:{\displaystyle G} 648:{\displaystyle G} 624:{\displaystyle K} 518:{\displaystyle G} 494:{\displaystyle G} 470:{\displaystyle n} 455:permutation group 446:{\displaystyle G} 373:{\displaystyle X} 353:{\displaystyle G} 329:{\displaystyle X} 309:{\displaystyle G} 294:permutation group 185:{\displaystyle X} 161:{\displaystyle G} 137:{\displaystyle X} 114:{\displaystyle G} 71:{\displaystyle G} 47:{\displaystyle G} 1841: 1807: 1800: 1793: 1771:abstract algebra 1765: 1758: 1739: 1738: 1718: 1712: 1711: 1691: 1675: 1673: 1672: 1667: 1655: 1653: 1652: 1647: 1636: 1635: 1540: 1538: 1537: 1532: 1520: 1518: 1517: 1512: 1501: 1500: 1399: 1397: 1396: 1391: 1380: 1379: 1277: 1275: 1274: 1269: 1257: 1255: 1254: 1249: 1237: 1235: 1234: 1229: 1205: 1203: 1202: 1197: 1161: 1159: 1158: 1153: 1151: 1150: 1129:For example, if 1125: 1123: 1122: 1117: 1105: 1103: 1102: 1097: 1085: 1083: 1082: 1077: 1065: 1063: 1062: 1057: 1045: 1043: 1042: 1037: 1013: 1011: 1010: 1005: 984: 982: 981: 976: 964: 962: 961: 956: 932: 930: 929: 924: 912: 910: 909: 904: 883: 881: 880: 875: 863: 861: 860: 855: 840: 838: 837: 832: 820: 818: 817: 812: 800: 798: 797: 792: 780: 778: 777: 772: 744: 742: 741: 736: 724: 722: 721: 716: 704: 702: 701: 696: 681: 679: 678: 673: 671: 670: 654: 652: 651: 646: 631:is an arbitrary 630: 628: 627: 622: 606: 604: 603: 598: 577: 575: 574: 569: 555: 554: 524: 522: 521: 516: 500: 498: 497: 492: 476: 474: 473: 468: 452: 450: 449: 444: 417: 415: 414: 409: 379: 377: 376: 371: 359: 357: 356: 351: 335: 333: 332: 327: 315: 313: 312: 307: 291: 289: 288: 283: 241: 239: 238: 233: 191: 189: 188: 183: 167: 165: 164: 159: 143: 141: 140: 135: 120: 118: 117: 112: 77: 75: 74: 69: 53: 51: 50: 45: 1849: 1848: 1844: 1843: 1842: 1840: 1839: 1838: 1814: 1813: 1812: 1811: 1748: 1743: 1742: 1735: 1719: 1715: 1708: 1692: 1688: 1683: 1661: 1658: 1657: 1630: 1629: 1624: 1619: 1613: 1612: 1607: 1602: 1596: 1595: 1590: 1585: 1575: 1574: 1548: 1545: 1544: 1526: 1523: 1522: 1495: 1494: 1489: 1484: 1478: 1477: 1472: 1467: 1461: 1460: 1455: 1450: 1440: 1439: 1407: 1404: 1403: 1374: 1373: 1368: 1363: 1357: 1356: 1351: 1346: 1340: 1339: 1334: 1329: 1319: 1318: 1286: 1283: 1282: 1263: 1260: 1259: 1243: 1240: 1239: 1211: 1208: 1207: 1167: 1164: 1163: 1146: 1142: 1134: 1131: 1130: 1111: 1108: 1107: 1091: 1088: 1087: 1071: 1068: 1067: 1051: 1048: 1047: 1022: 1019: 1018: 990: 987: 986: 970: 967: 966: 938: 935: 934: 918: 915: 914: 889: 886: 885: 869: 866: 865: 849: 846: 845: 826: 823: 822: 806: 803: 802: 786: 783: 782: 766: 763: 762: 759: 730: 727: 726: 710: 707: 706: 690: 687: 686: 666: 662: 660: 657: 656: 640: 637: 636: 616: 613: 612: 586: 583: 582: 550: 546: 532: 529: 528: 510: 507: 506: 486: 483: 482: 462: 459: 458: 438: 435: 434: 431: 388: 385: 384: 365: 362: 361: 345: 342: 341: 321: 318: 317: 301: 298: 297: 250: 247: 246: 200: 197: 196: 177: 174: 173: 170:symmetric group 153: 150: 149: 129: 126: 125: 106: 103: 102: 92: 63: 60: 59: 39: 36: 35: 21: 12: 11: 5: 1847: 1837: 1836: 1831: 1826: 1810: 1809: 1802: 1795: 1787: 1784: 1783: 1766: 1755: 1754: 1747: 1746:External links 1744: 1741: 1740: 1733: 1713: 1706: 1685: 1684: 1682: 1679: 1678: 1677: 1665: 1645: 1642: 1639: 1634: 1628: 1625: 1623: 1620: 1618: 1615: 1614: 1611: 1608: 1606: 1603: 1601: 1598: 1597: 1594: 1591: 1589: 1586: 1584: 1581: 1580: 1578: 1573: 1570: 1567: 1564: 1561: 1558: 1555: 1552: 1542: 1541:are fixed, and 1530: 1510: 1507: 1504: 1499: 1493: 1490: 1488: 1485: 1483: 1480: 1479: 1476: 1473: 1471: 1468: 1466: 1463: 1462: 1459: 1456: 1454: 1451: 1449: 1446: 1445: 1443: 1438: 1435: 1432: 1429: 1426: 1423: 1420: 1417: 1414: 1411: 1401: 1389: 1386: 1383: 1378: 1372: 1369: 1367: 1364: 1362: 1359: 1358: 1355: 1352: 1350: 1347: 1345: 1342: 1341: 1338: 1335: 1333: 1330: 1328: 1325: 1324: 1322: 1317: 1314: 1311: 1308: 1305: 1302: 1299: 1296: 1293: 1290: 1267: 1247: 1227: 1224: 1221: 1218: 1215: 1195: 1192: 1189: 1186: 1183: 1180: 1177: 1174: 1171: 1149: 1145: 1141: 1138: 1115: 1095: 1075: 1055: 1035: 1032: 1029: 1026: 1003: 1000: 997: 994: 974: 954: 951: 948: 945: 942: 922: 902: 899: 896: 893: 873: 853: 830: 810: 790: 770: 761:Given a group 758: 755: 734: 714: 694: 669: 665: 644: 620: 596: 593: 590: 579: 578: 567: 564: 561: 558: 553: 549: 545: 542: 539: 536: 514: 490: 466: 442: 430: 427: 419: 418: 407: 404: 401: 398: 395: 392: 369: 349: 325: 305: 281: 278: 275: 272: 269: 266: 263: 260: 257: 254: 243: 242: 231: 228: 225: 222: 219: 216: 213: 210: 207: 204: 181: 157: 133: 110: 91: 88: 78:as a group of 67: 56:representation 43: 9: 6: 4: 3: 2: 1846: 1835: 1832: 1830: 1827: 1825: 1822: 1821: 1819: 1808: 1803: 1801: 1796: 1794: 1789: 1788: 1782: 1780: 1776: 1772: 1767: 1764: 1760: 1759: 1753: 1750: 1749: 1736: 1734:9781468401288 1730: 1726: 1725: 1717: 1709: 1707:9781461207313 1703: 1699: 1698: 1690: 1686: 1663: 1643: 1640: 1632: 1626: 1621: 1616: 1609: 1604: 1599: 1592: 1587: 1582: 1576: 1568: 1565: 1562: 1556: 1550: 1543: 1528: 1508: 1505: 1497: 1491: 1486: 1481: 1474: 1469: 1464: 1457: 1452: 1447: 1441: 1433: 1430: 1427: 1418: 1409: 1402: 1387: 1384: 1376: 1370: 1365: 1360: 1353: 1348: 1343: 1336: 1331: 1326: 1320: 1312: 1309: 1306: 1297: 1288: 1281: 1280: 1279: 1265: 1245: 1225: 1219: 1213: 1190: 1187: 1184: 1181: 1178: 1172: 1169: 1147: 1143: 1139: 1136: 1127: 1113: 1093: 1073: 1053: 1030: 1024: 1015: 998: 992: 972: 952: 946: 940: 920: 897: 891: 871: 851: 844: 828: 808: 788: 768: 754: 752: 748: 732: 712: 692: 683: 667: 663: 642: 634: 618: 610: 594: 591: 588: 562: 556: 551: 547: 540: 537: 534: 527: 526: 525: 512: 504: 488: 480: 464: 456: 440: 426: 424: 405: 402: 396: 393: 390: 383: 382: 381: 367: 347: 339: 323: 303: 295: 276: 270: 267: 264: 258: 252: 229: 223: 217: 214: 208: 205: 202: 195: 194: 193: 179: 171: 155: 147: 131: 124: 108: 101: 97: 87: 85: 81: 65: 57: 41: 34: 30: 26: 19: 1779:expanding it 1768: 1723: 1716: 1696: 1689: 1128: 1016: 760: 684: 635:). That is, 580: 478: 432: 423:group action 420: 244: 146:homomorphism 95: 93: 80:permutations 28: 22: 747:translation 581:which maps 477:, then the 360:on the set 27:, the term 25:mathematics 1818:Categories 1681:References 933:. That is 457:of degree 245:The image 1676:is fixed. 1569:⁡ 1551:χ 1434:⁡ 1410:χ 1313:⁡ 1289:χ 1258:fixed by 1214:χ 1025:ρ 993:ρ 985:fixed by 941:χ 892:ρ 852:χ 843:character 841:then the 592:∈ 557:⁡ 544:→ 538:: 535:ρ 400:→ 394:× 271:⁡ 265:⊂ 253:ρ 218:⁡ 212:→ 206:: 203:ρ 655:acts on 501:is the 168:to the 1731:  1704:  1278:. So 611:(here 338:action 1769:This 801:with 633:field 453:is a 292:is a 148:from 144:is a 121:on a 100:group 98:of a 33:group 1775:stub 1729:ISBN 1702:ISBN 1162:and 1419:123 1126:. 1014:. 913:on 753:. 505:of 481:of 433:If 340:of 268:Sym 215:Sym 172:of 123:set 58:of 23:In 1820:: 1566:tr 1431:tr 1310:tr 1298:12 548:GL 380:: 192:: 94:A 1806:e 1799:t 1792:v 1781:. 1737:. 1710:. 1664:X 1644:3 1641:= 1638:) 1633:] 1627:1 1622:0 1617:0 1610:0 1605:1 1600:0 1593:0 1588:0 1583:1 1577:[ 1572:( 1563:= 1560:) 1557:1 1554:( 1529:X 1509:0 1506:= 1503:) 1498:] 1492:0 1487:0 1482:1 1475:1 1470:0 1465:0 1458:0 1453:1 1448:0 1442:[ 1437:( 1428:= 1425:) 1422:) 1416:( 1413:( 1388:1 1385:= 1382:) 1377:] 1371:1 1366:0 1361:0 1354:0 1349:0 1344:1 1337:0 1332:1 1327:0 1321:[ 1316:( 1307:= 1304:) 1301:) 1295:( 1292:( 1266:g 1246:X 1226:= 1223:) 1220:g 1217:( 1194:} 1191:3 1188:, 1185:2 1182:, 1179:1 1176:{ 1173:= 1170:X 1148:3 1144:S 1140:= 1137:G 1114:X 1094:X 1074:X 1054:X 1034:) 1031:g 1028:( 1002:) 999:g 996:( 973:X 953:= 950:) 947:g 944:( 921:X 901:) 898:g 895:( 872:X 829:X 809:G 789:X 769:G 733:G 713:G 693:G 668:n 664:K 643:G 619:K 595:G 589:g 566:) 563:K 560:( 552:n 541:G 513:G 489:G 465:n 441:G 406:. 403:X 397:X 391:G 368:X 348:G 324:X 304:G 280:) 277:X 274:( 262:) 259:G 256:( 230:. 227:) 224:X 221:( 209:G 180:X 156:G 132:X 109:G 66:G 42:G 20:.

Index

Permutation representation (disambiguation)
mathematics
group
representation
permutations
permutation matrices
group
set
homomorphism
symmetric group
permutation group
action
group action
permutation group
linear representation
permutation matrix
field
translation
regular representation
character
Permutation Groups
ISBN
9781461207313
A Course in the Theory of Groups
ISBN
9781468401288
https://mathoverflow.net/questions/286393/how-do-i-know-if-an-irreducible-representation-is-a-permutation-representation
Stub icon
abstract algebra
stub

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