Knowledge (XXG)

Adjunction space

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561: 205: 678:, (2006) available from amazon sites. Discusses the homotopy type of adjunction spaces, and uses adjunction spaces as an introduction to (finite) cell complexes. 684:"Note on a theorem due to Borsuk" Bull AMS 54 (1948), 1125-1132 is the earliest outside reference I know of using the term "adjuction space". 544: 671: 702: 151: 630: 540: 235: 114: 593:
are the maps obtained by composing the quotient map with the canonical injections into the disjoint union of
315:. Inductively attaching cells along their spherical boundaries to this space results in an example of a 80: 211: 552: 60: 548: 296: 697: 44: 681: 635: 691: 572: 323: 560: 28: 663: 482: 316: 17: 507: 346: 338:
before attaching the boundaries of the removed balls along an attaching map.
658: 327: 40: 675: 263:). The topology, however, is specified by the quotient construction. 312: 651:, (1970) Addison-Wesley Publishing Company, Reading Massachusetts. 613:
is also an inclusion the attaching construction is to simply glue
364:
is a space with one point then the adjunction is the quotient
402:
are in 1-1 correspondence with the pairs of continuous maps
47:
is attached or "glued" onto another. Specifically, let
287:
A common example of an adjunction space is given when
345:
is a space with one point then the adjunction is the
154: 609:—the construction is similar. Conversely, if 601:. One can form a more general pushout by replacing 199: 539:The attaching construction is an example of a 200:{\displaystyle X\cup _{f}Y=(X\sqcup Y)/\sim } 8: 547:. That is to say, the adjunction space is 330:. Here, one first removes open balls from 322:Adjunction spaces are also used to define 189: 162: 153: 676:"Topology and Groupoids" pdf available 621:together along their common subspace. 653:(Provides a very brief introduction.) 7: 307:is the boundary of the ball, the ( 251:consists of the disjoint union of 87:). One forms the adjunction space 25: 605:with an arbitrary continuous map 559: 234:, and the quotient is given the 55:be topological spaces, and let 551:with respect to the following 545:category of topological spaces 266:Intuitively, one may think of 186: 174: 39:) is a common construction in 1: 100:(sometimes also written as 719: 489:one can show that the map 535:Categorical description 531:is an open embedding. 201: 202: 381:The continuous maps 270:as being glued onto 212:equivalence relation 152: 553:commutative diagram 703:Topological spaces 659:"Adjunction space" 477:In the case where 214:~ is generated by 197: 647:Stephen Willard, 236:quotient topology 45:topological space 16:(Redirected from 710: 682:J.H.C. Whitehead 668: 649:General Topology 636:Mapping cylinder 563: 206: 204: 203: 198: 193: 167: 166: 125:and identifying 113:) by taking the 33:adjunction space 21: 718: 717: 713: 712: 711: 709: 708: 707: 688: 687: 657: 644: 627: 592: 583: 565: 537: 527: 502: 461: 444: 427: 410: 394: 379: 284: 247: 158: 150: 149: 109: 96: 37:attaching space 23: 22: 15: 12: 11: 5: 716: 714: 706: 705: 700: 690: 689: 686: 685: 679: 669: 655: 643: 640: 639: 638: 633: 631:Quotient space 626: 623: 588: 579: 557: 536: 533: 523: 498: 457: 440: 423: 406: 390: 378: 375: 374: 373: 358: 339: 324:connected sums 320: 283: 280: 243: 208: 207: 196: 192: 188: 185: 182: 179: 176: 173: 170: 165: 161: 157: 115:disjoint union 105: 92: 81:continuous map 24: 14: 13: 10: 9: 6: 4: 3: 2: 715: 704: 701: 699: 696: 695: 693: 683: 680: 677: 673: 670: 666: 665: 660: 656: 654: 650: 646: 645: 641: 637: 634: 632: 629: 628: 624: 622: 620: 616: 612: 608: 604: 600: 596: 591: 587: 582: 578: 574: 573:inclusion map 570: 564: 562: 556: 554: 550: 546: 542: 534: 532: 530: 526: 521: 517: 513: 509: 505: 501: 496: 492: 488: 484: 480: 475: 473: 469: 465: 460: 456: 452: 448: 443: 439: 436:that satisfy 435: 431: 426: 422: 418: 414: 409: 405: 401: 397: 393: 388: 384: 376: 371: 367: 363: 359: 356: 352: 348: 344: 340: 337: 333: 329: 325: 321: 318: 314: 310: 306: 302: 298: 294: 290: 286: 285: 281: 279: 277: 273: 269: 264: 262: 258: 254: 250: 246: 241: 237: 233: 229: 225: 221: 217: 213: 194: 190: 183: 180: 177: 171: 168: 163: 159: 155: 148: 147: 146: 144: 140: 136: 132: 128: 124: 120: 116: 112: 108: 103: 99: 95: 90: 86: 85:attaching map 82: 78: 74: 70: 66: 62: 58: 54: 50: 46: 42: 38: 34: 30: 19: 18:Attaching map 672:Ronald Brown 662: 652: 648: 618: 614: 610: 606: 602: 598: 594: 589: 585: 580: 576: 568: 566: 558: 538: 528: 524: 519: 515: 511: 506:is a closed 503: 499: 494: 490: 486: 485:subspace of 478: 476: 471: 467: 463: 458: 454: 450: 446: 441: 437: 433: 429: 424: 420: 416: 412: 407: 403: 399: 395: 391: 386: 382: 380: 369: 365: 361: 354: 350: 342: 335: 331: 308: 304: 300: 292: 291:is a closed 288: 275: 274:via the map 271: 267: 265: 260: 256: 252: 248: 244: 239: 238:. As a set, 231: 227: 223: 219: 215: 209: 145:. Formally, 142: 138: 134: 130: 126: 122: 118: 110: 106: 101: 97: 93: 88: 84: 83:(called the 76: 72: 68: 64: 56: 52: 48: 36: 32: 26: 29:mathematics 692:Categories 664:PlanetMath 642:References 466:) for all 377:Properties 317:CW complex 226:) for all 210:where the 137:) for all 43:where one 549:universal 508:embedding 347:wedge sum 328:manifolds 195:∼ 181:⊔ 160:∪ 698:Topology 625:See also 432:→ 428: : 415:→ 411: : 398:→ 385: : 282:Examples 71: : 61:subspace 41:topology 571:is the 543:in the 541:pushout 483:closed 313:sphere 303:) and 67:. Let 567:Here 510:and ( 481:is a 255:and ( 129:with 79:be a 59:be a 31:, an 617:and 597:and 575:and 518:) → 419:and 353:and 334:and 311:−1)- 301:cell 299:(or 297:ball 121:and 51:and 35:(or 470:in 453:))= 360:If 349:of 341:If 326:of 230:in 141:in 117:of 63:of 27:In 694:: 674:, 661:. 584:, 555:: 514:− 493:→ 474:. 278:. 259:− 218:~ 75:→ 667:. 619:Y 615:X 611:f 607:g 603:i 599:Y 595:X 590:Y 586:Φ 581:X 577:Φ 569:i 529:Y 525:f 522:∪ 520:X 516:A 512:Y 504:Y 500:f 497:∪ 495:X 491:X 487:Y 479:A 472:A 468:a 464:a 462:( 459:Y 455:h 451:a 449:( 447:f 445:( 442:X 438:h 434:Z 430:Y 425:Y 421:h 417:Z 413:X 408:X 404:h 400:Z 396:Y 392:f 389:∪ 387:X 383:h 372:. 370:A 368:/ 366:Y 362:X 357:. 355:Y 351:X 343:A 336:Y 332:X 319:. 309:n 305:A 295:- 293:n 289:Y 276:f 272:X 268:Y 261:A 257:Y 253:X 249:Y 245:f 242:∪ 240:X 232:A 228:a 224:a 222:( 220:f 216:a 191:/ 187:) 184:Y 178:X 175:( 172:= 169:Y 164:f 156:X 143:A 139:a 135:a 133:( 131:f 127:a 123:Y 119:X 111:Y 107:f 104:+ 102:X 98:Y 94:f 91:∪ 89:X 77:X 73:A 69:f 65:Y 57:A 53:Y 49:X 20:)

Index

Attaching map
mathematics
topology
topological space
subspace
continuous map
disjoint union
equivalence relation
quotient topology
ball
sphere
CW complex
connected sums
manifolds
wedge sum
closed
embedding
pushout
category of topological spaces
universal
commutative diagram

inclusion map
Quotient space
Mapping cylinder
"Adjunction space"
PlanetMath
Ronald Brown
"Topology and Groupoids" pdf available
J.H.C. Whitehead

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