Knowledge (XXG)

Elementary divisors

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of the module by decomposing each of them as far as possible into pairwise relatively prime (non-unit) factors, which will be powers of irreducible elements. This decomposition corresponds to maximally decomposing each submodule corresponding to an invariant factor by using the
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of elementary divisors, the invariant factors can be found, starting from the final one (which is a multiple of all others), as follows. For each irreducible element
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The list of primary ideals is unique up to order (but a given ideal may be present more than once, so the list represents a
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occurs among the elementary divisors. The elementary divisors can be obtained from the list of
543: 519: 498: 493: 430: 210:{\displaystyle M\cong R^{r}\oplus \bigoplus _{i=1}^{l}R/(q_{i})\qquad {\text{with }}r,l\geq 0} 584: 226: 553: 270: 557: 580: 385: 357: 295: 89: 69: 45: 627: 511: 257: 572: 535: 37:
structure theorem for finitely generated modules over a principal ideal domain
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The module is determined up to isomorphism by specifying its free rank
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is non-empty, repeat to find the invariant factors before it.
588: 388: 360: 308: 273: 229: 121: 92: 72: 48: 411:, and for class of associated irreducible elements 542:(Third ed.), Reading, Mass.: Addison-Wesley, 394: 366: 346: 286: 248: 209: 98: 78: 54: 354:of irreducible elements. The nonnegative integer 466:, take the highest such power, removing it from 478:to give the final invariant factor; as long as 608: 8: 615: 601: 110:is isomorphic to a finite sum of the form 387: 359: 336: 331: 326: 313: 307: 278: 272: 237: 228: 187: 177: 165: 156: 145: 132: 120: 91: 71: 47: 7: 569: 567: 442:. Conversely, knowing the multiset 347:{\displaystyle q_{i}=p_{i}^{r_{i}}} 587:. You can help Knowledge (XXG) by 14: 516:Rings, modules and linear algebra 267:of primary ideals); the elements 571: 186: 35:(PID) occur in one form of the 243: 230: 183: 170: 1: 655: 566: 417:and each positive integer 436:Chinese remainder theorem 423:the number of times that 249:{\displaystyle (q_{i})} 583:-related article is a 533:Chap. III.7, p.153 of 514:; T.O. Hawkes (1970). 396: 368: 348: 294:are unique only up to 288: 250: 211: 161: 100: 80: 56: 33:principal ideal domain 454:such that some power 397: 369: 349: 298:, and are called the 289: 287:{\displaystyle q_{i}} 251: 212: 141: 101: 86:a finitely generated 81: 57: 639:Linear algebra stubs 518:. Chapman and Hall. 386: 358: 306: 271: 227: 119: 90: 70: 46: 343: 300:elementary divisors 25:elementary divisors 392: 364: 344: 322: 284: 246: 207: 96: 76: 52: 596: 595: 549:978-0-201-55540-0 499:Smith normal form 494:Invariant factors 431:invariant factors 395:{\displaystyle M} 367:{\displaystyle r} 190: 99:{\displaystyle R} 79:{\displaystyle M} 55:{\displaystyle R} 16:Algebraic formula 646: 617: 610: 603: 575: 568: 560: 529: 483: 477: 471: 465: 459: 453: 447: 428: 422: 416: 410: 401: 399: 398: 393: 373: 371: 370: 365: 353: 351: 350: 345: 342: 341: 340: 330: 318: 317: 293: 291: 290: 285: 283: 282: 255: 253: 252: 247: 242: 241: 216: 214: 213: 208: 191: 188: 182: 181: 169: 160: 155: 137: 136: 105: 103: 102: 97: 85: 83: 82: 77: 61: 59: 58: 53: 654: 653: 649: 648: 647: 645: 644: 643: 624: 623: 622: 621: 564: 550: 534: 530:Chap.11, p.182. 526: 510: 507: 490: 479: 473: 467: 461: 455: 449: 443: 424: 418: 412: 406: 384: 383: 356: 355: 332: 309: 304: 303: 274: 269: 268: 233: 225: 224: 173: 128: 117: 116: 88: 87: 68: 67: 44: 43: 17: 12: 11: 5: 652: 650: 642: 641: 636: 626: 625: 620: 619: 612: 605: 597: 594: 593: 581:linear algebra 576: 562: 561: 548: 531: 524: 506: 503: 502: 501: 496: 489: 486: 391: 382:of the module 374:is called the 363: 339: 335: 329: 325: 321: 316: 312: 296:associatedness 281: 277: 258:primary ideals 245: 240: 236: 232: 221: 220: 219: 218: 206: 203: 200: 197: 194: 185: 180: 176: 172: 168: 164: 159: 154: 151: 148: 144: 140: 135: 131: 127: 124: 106:-module, then 95: 75: 51: 15: 13: 10: 9: 6: 4: 3: 2: 651: 640: 637: 635: 634:Module theory 632: 631: 629: 618: 613: 611: 606: 604: 599: 598: 592: 590: 586: 582: 577: 574: 570: 565: 559: 555: 551: 545: 541: 537: 532: 527: 525:0-412-09810-5 521: 517: 513: 509: 508: 504: 500: 497: 495: 492: 491: 487: 485: 482: 476: 470: 464: 458: 452: 446: 441: 437: 432: 427: 421: 415: 409: 403: 389: 381: 377: 361: 337: 333: 327: 323: 319: 314: 310: 301: 297: 279: 275: 266: 261: 259: 238: 234: 204: 201: 198: 195: 192: 178: 174: 166: 162: 157: 152: 149: 146: 142: 138: 133: 129: 125: 122: 115: 114: 113: 112: 111: 109: 93: 73: 65: 49: 40: 38: 34: 30: 26: 22: 589:expanding it 578: 563: 539: 515: 480: 474: 468: 462: 456: 450: 444: 439: 425: 419: 413: 407: 404: 380:Betti number 379: 375: 299: 262: 256:are nonzero 222: 107: 41: 24: 18: 536:Lang, Serge 628:Categories 558:0848.13001 512:B. Hartley 505:References 460:occurs in 223:where the 189:with  376:free rank 202:≥ 143:⨁ 139:⊕ 126:≅ 538:(1993), 488:See also 265:multiset 540:Algebra 31:over a 21:algebra 556:  546:  522:  29:module 23:, the 579:This 62:is a 27:of a 585:stub 544:ISBN 520:ISBN 438:for 66:and 554:Zbl 378:or 64:PID 42:If 19:In 630:: 552:, 402:. 260:. 39:. 616:e 609:t 602:v 591:. 528:. 481:M 475:p 469:M 463:M 457:p 451:p 445:M 440:R 426:p 420:k 414:p 408:r 390:M 362:r 338:i 334:r 328:i 324:p 320:= 315:i 311:q 280:i 276:q 244:) 239:i 235:q 231:( 217:, 205:0 199:l 196:, 193:r 184:) 179:i 175:q 171:( 167:/ 163:R 158:l 153:1 150:= 147:i 134:r 130:R 123:M 108:M 94:R 74:M 50:R

Index

algebra
module
principal ideal domain
structure theorem for finitely generated modules over a principal ideal domain
PID
primary ideals
multiset
associatedness
invariant factors
Chinese remainder theorem
Invariant factors
Smith normal form
B. Hartley
ISBN
0-412-09810-5
Lang, Serge
ISBN
978-0-201-55540-0
Zbl
0848.13001
Stub icon
linear algebra
stub
expanding it
v
t
e
Categories
Module theory
Linear algebra stubs

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