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Talk:Constant of motion

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408:...And I looked at the other edits a bit; I see you shuffled some stuff off to the bottom. The point is not to get tangled by quantum chaos, which is an interesting but irrelevant distraction, but to instead make the statement "system with constants of motion == integrable system == system with symmetries" and conversely, "non-integrable system == system with no constants of motion". I don't know if there's a grand theorem that makes this statement, or what the name of this theorem is, but this seems to be the over-arching "great truth" of differential equations at this point in history. Furthermore, this connection should be put up-front and center to the article, not buried in its bowels. Unfortunately, I am no expert in this; I'm just repeating what all the experts say. 00:25, 13 June 2006 (UTC) 95: 31: 85: 64: 22: 173: 537: 531: 534: 280:
Well -- I have only a hand-waving answer. If there are not constants of motion, then the system is free to visit all phase space... and it will. If it does not visit all of phase space, then there is some constant of motion that you failed to recognize. If the system visits all of phase space, the
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by Binney and Tremaine, a constant of motion is a function of phase-space coordinate (position and velocity) and time, and an integral of motion is a function of only the phase-space coordinates. Every integral of motion is a constant of motion, but the converse is not true. I will insert this
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will make this clear. At a certain conceptual level, you may be right. At a practical level, tools, techniques and theorems are lacking. I've got one highly abstract paper that takes 100 pages to quantize the simple harmonic oscillator as a "simple example problem". :-)
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reveals that they either explicitly says they are synonyms, or they make the subtle distinction of using "integral of motion" for the expression that is constant, and "constant of motion" for the value at which it is constant. In either case the two articles should be
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Chaotic systems need to satisfy properties that don't seem to follow necessarily from "only energy is conserved", e.g., orbits of initially close conditions diverge exponentially and become topologically mixed. Maybe it's too early in the morning -- am I missing
316:. I'm unfamiliar with the quantum chaos literature, but I would be surprised if there were any obstacle to applying the Feynman path integral method to a mechanical system with a finite number of degrees of freedom. Could you point me to a reference? 472:; without checking Goldstein, I do not recall any constants of motion that cannot be expressed as an integration constant, so they might be exactly synonymous. I say wait a few days and then go for it. - 582: 35: 602: 587: 297:"), which say "if it can occupy all phase space, it will, and furthermore, it will be hyperbolic in doing so." There are some more precise statements, but I don't know them by name. 572: 361:, (1990) Springer-Verlag. Very sharp and insightful, completely free of mathematical mumbo-jumbo, throughly approachable by anyone who's gone through undergrad physics. 151: 285:, or possibly more strongly mixing than that. I don't know any truly mathematical statements for this, but a pseudo-mathematical argument is that there are 577: 386:, an article I've toyed with writing myself for a long time. Good job. You may want to tie this article more strongly to that one: The constants of motion 597: 567: 141: 94: 592: 496: 489:
Can't an integral of motion have an implicit time dependence whilst a constant of motion not? I don't think these two should be merged.
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An examination of the first few hits on google books that mention both "integral of motion" and "constant of motion" (
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article is too abstract; but perhaps you might have the confidence to write a simplified intro for it?)
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There seem to be several chaotic systems in which energy is not conserved, e.g., the driven pendulum?
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are synonyms. So they should be merged. Question remains, what should be the main article? (
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the actions, and v.v.; both notions are at the core of the idea of an
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distinction into the article, but feel free to elaborate more on it.
423:. I'll see if I can come up with a more direct, concrete statement. 294: 286: 167: 15: 223:(system in which only energy is conserved) = (chaotic system) 314:
non-integrable systems cannot be quantized consistently
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112:, a collaborative effort to improve the coverage of 603:Start-Class physics articles of High-importance 588:Start-Class vital articles in Physical sciences 573:Knowledge vital articles in Physical sciences 281:question becomes only whether it is "merely" 8: 415:I'm digging around now. The key pieces are 198:; for the discussion at that location, see 19: 58: 249:Yes, you are correct, I was being sloppy. 359:Chaos in Classical and Quantum Mechanics 60: 7: 106:This article is within the scope of 49:It is of interest to the following 578:Start-Class level-5 vital articles 14: 421:Liouville's theorem (Hamiltonian) 598:High-importance physics articles 568:Knowledge level-5 vital articles 171: 93: 83: 62: 29: 20: 146:This article has been rated as 1: 126:Knowledge:WikiProject Physics 120:and see a list of open tasks. 593:Start-Class physics articles 484:13:45, 30 January 2009 (UTC) 458:09:14, 30 January 2009 (UTC) 129:Template:WikiProject Physics 382:I was also looking at your 619: 563:Start-Class vital articles 357:Try Martin C. Gutzwiller, 152:project's importance scale 505:14:18, 27 July 2010 (UTC) 428:03:30, 13 June 2006 (UTC) 403:15:09, 12 June 2006 (UTC) 366:14:58, 12 June 2006 (UTC) 339:14:52, 12 June 2006 (UTC) 321:10:38, 12 June 2006 (UTC) 145: 78: 57: 312:(2) The second was that 548:08:09, 6 May 2011 (UTC) 525:00:48, 6 May 2011 (UTC) 329:Just about any text in 221:(1) The first was that 384:action-angle variables 378:Action-angle variables 178:The contents of the 36:level-5 vital article 293:systems ("chaos is 109:WikiProject Physics 446:integral of motion 442:constant of motion 190:Constant of motion 181:Integral of motion 45:content assessment 512:Galactic Dynamics 495:comment added by 482: 440:As for as I know 417:Frobenius theorem 396:integrable system 392:integrable system 206: 205: 166: 165: 162: 161: 158: 157: 610: 507: 476: 464:Looks more like 197: 175: 174: 168: 134: 133: 132:physics articles 130: 127: 124: 103: 98: 97: 87: 80: 79: 74: 66: 59: 42: 33: 32: 25: 24: 16: 618: 617: 613: 612: 611: 609: 608: 607: 553: 552: 490: 468:is a subset of 438: 380: 301:pops into mind. 211: 193: 172: 148:High-importance 131: 128: 125: 122: 121: 99: 92: 73:High‑importance 72: 43:on Knowledge's 40: 30: 12: 11: 5: 616: 614: 606: 605: 600: 595: 590: 585: 580: 575: 570: 565: 555: 554: 551: 550: 497:143.239.65.254 487: 486: 437: 436:Merge proposal 434: 433: 432: 431: 430: 410: 409: 379: 376: 375: 374: 373: 372: 371: 370: 369: 368: 348: 347: 346: 345: 344: 343: 342: 341: 309: 308: 307: 306: 305: 304: 303: 302: 271: 270: 269: 268: 267: 266: 257: 256: 255: 254: 253: 252: 251: 250: 240: 239: 238: 237: 236: 235: 227: 226: 210: 207: 204: 203: 176: 164: 163: 160: 159: 156: 155: 144: 138: 137: 135: 118:the discussion 105: 104: 101:Physics portal 88: 76: 75: 67: 55: 54: 48: 26: 13: 10: 9: 6: 4: 3: 2: 615: 604: 601: 599: 596: 594: 591: 589: 586: 584: 581: 579: 576: 574: 571: 569: 566: 564: 561: 560: 558: 549: 546: 543: 538: 536: 533: 529: 528: 527: 526: 522: 518: 513: 510:According to 508: 506: 502: 498: 494: 485: 480: 475: 471: 467: 463: 462: 461: 459: 455: 451: 447: 443: 435: 429: 426: 422: 418: 414: 413: 412: 411: 407: 406: 405: 404: 401: 397: 393: 389: 385: 377: 367: 364: 360: 356: 355: 354: 353: 352: 351: 350: 349: 340: 337: 332: 331:quantum chaos 328: 327: 326: 325: 324: 323: 322: 319: 315: 311: 310: 300: 296: 292: 289:theorems for 288: 284: 279: 278: 277: 276: 275: 274: 273: 272: 263: 262: 261: 260: 259: 258: 248: 247: 246: 245: 244: 243: 242: 241: 233: 232: 231: 230: 229: 228: 224: 220: 219: 218: 216: 209:Two Questions 208: 201: 200:its talk page 196: 191: 187: 183: 182: 177: 170: 169: 153: 149: 143: 140: 139: 136: 119: 115: 111: 110: 102: 96: 91: 89: 86: 82: 81: 77: 71: 68: 65: 61: 56: 52: 46: 38: 37: 27: 23: 18: 17: 511: 509: 488: 469: 465: 439: 387: 381: 358: 313: 222: 212: 179: 147: 107: 51:WikiProjects 34: 491:—Preceding 450:TimothyRias 394:. (and the 195:its history 41:Start-class 557:Categories 265:something? 184:page were 291:expansive 39:is rated 493:unsigned 474:Eldereft 470:constant 466:integral 540:merged. 517:PSimeon 318:WillowW 299:Axiom A 283:ergodic 150:on the 123:Physics 114:Physics 70:Physics 186:merged 47:scale. 479:cont. 425:linas 400:linas 363:linas 336:linas 295:rigid 287:rigid 215:Linas 188:into 28:This 535:link 532:link 521:talk 501:talk 454:talk 444:and 419:and 142:High 388:are 213:Hi 559:: 523:) 503:) 460:) 456:) 545:R 542:T 519:( 499:( 481:) 477:( 452:( 225:. 202:. 154:. 53::

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10:38, 12 June 2006 (UTC)
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linas
14:52, 12 June 2006 (UTC)

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