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Talk:Affine connection

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289:, which the author gave the unfortunate name "affine connection". Which... is not a good name. It is probably safe to say that the connection on the affine bundle is a kind of an affine connection, but it is not at all the same thing as "the affine connection" defined here. The non-standard notation is then a by-product of trying to distinguish between a tangent bundle, and the associated affine bundle derived from it. There might be some pile of commonalities, but without a reference at one's fingertips and some hard work, stating them/merging them is impossible. So I'm now retracting the merge tags. Heh. 84: 74: 53: 396:, instead of df(X)Y as the article currently states, since below it states that this criteria implies that the connection depends on X at only the very point under consideration, and depends on Y in a neighborhood of that point. Doesn't that only hold if the df is applied to Y? Also, describing this property as being analogous to the product rule suggests to me that the df is applied to the Y, since that is more similar to the product rule. 163: 263:. That is clear in the article but not the stub. Why mention "jets"? The compatibility conditions for affine connections are described in both sources but in the stub are almost undecipherable. Similarly, the Cartan formulation in terms of 1-forms is well presented in Helgason and K & N, but completely opaque in the stub. The editor who created most of this content was 22: 238:
on the other hand is unreadable. Standard textbooks, e.g. those of Kobayashi & Nomizu or Helgason, do not use the notation of the stub. I do not agree that the content from there should be merged. It is quite clear that the editor deliberately used notation that is
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Cartan 1926 Acta Math. paper title is actually "Les groupes d’holonomie des espaces généralisés". Title in Knowledge article became "Espaces à connexion affine, projective et conforme". I do not know whether the title or the ref is wrong.
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consists of a cut-n-paste of a bunch of standard eqns from a standard textbook, with zero explanation or commentary. I propose that all of that content should be moved here, where at least we get some explanations.
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Oh, I see what the problem is. Now that I read it more carefully, I can see that the stub is about connections on
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Perhaps I'm wrong, since I'm not well-versed in this, but based on the context, I would expect it should say
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on Knowledge. If you would like to participate, please visit the project page, where you can join
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While awkward, the original is correct. The differential operator being applied is
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standard. An affine connection defines a way for tangent vector fields
198: 156: 15: 508:{\displaystyle \nabla _{X}fY=(\nabla _{X}f)Y+f\nabla _{X}Y} 307:
Dubious tag on Formal Definition as a Differential Operator
515:. The covariant derivative for functions is defined to be 773:{\displaystyle \nabla _{X}fY=Y\nabla _{X}f+f\nabla _{X}Y} 576:. These are different notations for the derivative of 389:{\displaystyle \nabla _{X}f(Y)=Xdf(Y)+f(\nabla _{X}Y)} 804: 715: 665: 645: 622: 602: 582: 521: 444: 438:. Most straightforwardly the Leibniz rule is written 417: 317: 101:, a collaborative effort to improve the coverage of 867:{\displaystyle \nabla _{X}(fY)=(Xf)Y+f\nabla _{X}Y} 866: 772: 701: 651: 631: 608: 588: 568: 507: 430: 388: 569:{\displaystyle \nabla _{X}f=X(f)=\partial _{X}f} 8: 882:over the ring of differentiable functions 47: 855: 809: 803: 761: 742: 720: 714: 664: 644: 621: 601: 581: 557: 526: 520: 496: 471: 449: 443: 422: 416: 374: 322: 316: 234:The current article seems fine. The stub 709:Edited: originally had Leibniz rule as 49: 19: 7: 267:. He created his own wikipedia page 95:This article is within the scope of 38:It is of interest to the following 852: 806: 758: 739: 717: 554: 523: 493: 468: 446: 419: 371: 319: 14: 962:Mid-priority mathematics articles 115:Knowledge:WikiProject Mathematics 253:of a fixed vector bundle, i.e. 161: 118:Template:WikiProject Mathematics 82: 72: 51: 20: 135:This article has been rated as 839: 830: 824: 815: 693: 687: 678: 672: 547: 541: 480: 464: 383: 367: 358: 352: 337: 331: 1: 109:and see a list of open tasks. 957:B-Class mathematics articles 299:21:46, 25 October 2020 (UTC) 281:00:39, 25 October 2020 (UTC) 229:18:43, 24 October 2020 (UTC) 702:{\displaystyle df(X)=X(f).} 431:{\displaystyle \nabla _{X}} 978: 236:connection (affine bundle) 216:connection (affine bundle) 209:connection (affine bundle) 943:21:33, 15 June 2022 (UTC) 908:Changed it now - thanks. 406:02:14, 3 March 2021 (UTC) 134: 67: 46: 141:project's priority scale 918:23:56, 6 May 2022 (UTC) 896:23:43, 6 May 2022 (UTC) 790:22:36, 6 May 2022 (UTC) 98:WikiProject Mathematics 868: 774: 703: 653: 633: 616:. Written in terms of 610: 590: 570: 509: 432: 390: 28:This article is rated 869: 775: 704: 654: 634: 611: 591: 571: 510: 433: 391: 269:Gennadi Sardanashvily 910:Zephyr the west wind 802: 782:Zephyr the west wind 713: 663: 643: 620: 600: 596:in the direction of 580: 519: 442: 415: 315: 121:mathematics articles 249:to act on sections 864: 770: 699: 649: 639:, the gradient of 632:{\displaystyle df} 629: 606: 586: 566: 505: 428: 386: 271:but died in 2016. 90:Mathematics portal 34:content assessment 652:{\displaystyle f} 609:{\displaystyle X} 589:{\displaystyle f} 204: 203: 185: 184: 155: 154: 151: 150: 147: 146: 969: 885: 877: 873: 871: 870: 865: 860: 859: 814: 813: 779: 777: 776: 771: 766: 765: 747: 746: 725: 724: 708: 706: 705: 700: 659:, you can write 658: 656: 655: 650: 638: 636: 635: 630: 615: 613: 612: 607: 595: 593: 592: 587: 575: 573: 572: 567: 562: 561: 531: 530: 514: 512: 511: 506: 501: 500: 476: 475: 454: 453: 437: 435: 434: 429: 427: 426: 395: 393: 392: 387: 379: 378: 327: 326: 262: 252: 248: 199: 176: 175: 165: 157: 123: 122: 119: 116: 113: 92: 87: 86: 76: 69: 68: 63: 55: 48: 31: 25: 24: 16: 977: 976: 972: 971: 970: 968: 967: 966: 947: 946: 935:Arnaud Chéritat 930: 928:Ref title wrong 883: 875: 851: 805: 800: 799: 798:This should be 757: 738: 716: 711: 710: 661: 660: 641: 640: 618: 617: 598: 597: 578: 577: 553: 522: 517: 516: 492: 467: 445: 440: 439: 418: 413: 412: 370: 318: 313: 312: 309: 260: 254: 250: 244: 212: 200: 194: 170: 120: 117: 114: 111: 110: 88: 81: 61: 32:on Knowledge's 29: 12: 11: 5: 975: 973: 965: 964: 959: 949: 948: 929: 926: 925: 924: 923: 922: 921: 920: 901: 900: 899: 898: 863: 858: 854: 850: 847: 844: 841: 838: 835: 832: 829: 826: 823: 820: 817: 812: 808: 793: 792: 769: 764: 760: 756: 753: 750: 745: 741: 737: 734: 731: 728: 723: 719: 698: 695: 692: 689: 686: 683: 680: 677: 674: 671: 668: 648: 628: 625: 605: 585: 565: 560: 556: 552: 549: 546: 543: 540: 537: 534: 529: 525: 504: 499: 495: 491: 488: 485: 482: 479: 474: 470: 466: 463: 460: 457: 452: 448: 425: 421: 385: 382: 377: 373: 369: 366: 363: 360: 357: 354: 351: 348: 345: 342: 339: 336: 333: 330: 325: 321: 308: 305: 304: 303: 302: 301: 287:affine bundles 256: 211: 205: 202: 201: 196: 192: 190: 187: 186: 183: 182: 172: 171: 166: 160: 153: 152: 149: 148: 145: 144: 133: 127: 126: 124: 107:the discussion 94: 93: 77: 65: 64: 56: 44: 43: 37: 26: 13: 10: 9: 6: 4: 3: 2: 974: 963: 960: 958: 955: 954: 952: 945: 944: 940: 936: 927: 919: 915: 911: 907: 906: 905: 904: 903: 902: 897: 893: 889: 881: 861: 856: 848: 845: 842: 836: 833: 827: 821: 818: 810: 797: 796: 795: 794: 791: 787: 783: 767: 762: 754: 751: 748: 743: 735: 732: 729: 726: 721: 696: 690: 684: 681: 675: 669: 666: 646: 626: 623: 603: 583: 563: 558: 550: 544: 538: 535: 532: 527: 502: 497: 489: 486: 483: 477: 472: 461: 458: 455: 450: 423: 410: 409: 408: 407: 403: 399: 380: 375: 364: 361: 355: 349: 346: 343: 340: 334: 328: 323: 306: 300: 296: 292: 288: 284: 283: 282: 278: 274: 270: 266: 259: 247: 242: 237: 233: 232: 231: 230: 226: 222: 217: 210: 206: 189: 188: 181: 178: 177: 174: 173: 169: 164: 159: 158: 142: 138: 132: 129: 128: 125: 108: 104: 100: 99: 91: 85: 80: 78: 75: 71: 70: 66: 60: 57: 54: 50: 45: 41: 35: 27: 23: 18: 17: 931: 879: 310: 291:67.198.37.16 257: 245: 240: 221:67.198.37.16 214:The article 213: 167: 137:Mid-priority 136: 96: 62:Mid‑priority 40:WikiProjects 880:left module 112:Mathematics 103:mathematics 59:Mathematics 951:Categories 265:User:Gsard 207:mergefrom 180:Archive 1 168:Archives 888:Mathsci 398:Ramzuiv 273:Mathsci 139:on the 30:B-class 878:are a 36:scale. 939:talk 914:talk 892:talk 786:talk 402:talk 295:talk 277:talk 225:talk 241:not 131:Mid 953:: 941:) 916:) 894:) 886:. 853:∇ 807:∇ 788:) 759:∇ 740:∇ 718:∇ 555:∂ 524:∇ 494:∇ 469:∇ 447:∇ 420:∇ 404:) 372:∇ 320:∇ 297:) 279:) 227:) 937:( 912:( 890:( 884:f 876:X 862:Y 857:X 849:f 846:+ 843:Y 840:) 837:f 834:X 831:( 828:= 825:) 822:Y 819:f 816:( 811:X 784:( 780:. 768:Y 763:X 755:f 752:+ 749:f 744:X 736:Y 733:= 730:Y 727:f 722:X 697:. 694:) 691:f 688:( 685:X 682:= 679:) 676:X 673:( 670:f 667:d 647:f 627:f 624:d 604:X 584:f 564:f 559:X 551:= 548:) 545:f 542:( 539:X 536:= 533:f 528:X 503:Y 498:X 490:f 487:+ 484:Y 481:) 478:f 473:X 465:( 462:= 459:Y 456:f 451:X 424:X 400:( 384:) 381:Y 376:X 368:( 365:f 362:+ 359:) 356:Y 353:( 350:f 347:d 344:X 341:= 338:) 335:Y 332:( 329:f 324:X 293:( 275:( 261:ξ 258:X 255:∇ 251:ξ 246:X 223:( 143:. 42::

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Archive 1
connection (affine bundle)
connection (affine bundle)
67.198.37.16
talk
18:43, 24 October 2020 (UTC)
connection (affine bundle)
User:Gsard
Gennadi Sardanashvily
Mathsci
talk
00:39, 25 October 2020 (UTC)
affine bundles
67.198.37.16
talk
21:46, 25 October 2020 (UTC)

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