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Talk:Titchmarsh theorem

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I don't typically mind using where to have an implied existential quantifier, but usually because the primary subject of the sentence is also just being introduced. In this case though, it really does read poorly. I replaced "where" with "for some" as you suggested. The functions f and g are both
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real valued, so they are just F's real and imaginary parts, and the theorem is saying they must be in the relation that −g is the hilbert transform of f. This could probably be phrased more clearly, but it would take a more awake editor than myself.
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This is mostly what I had in mind, but there is a problem with the theorem right now. Basically the second condition as stated simply evaluates to false, so something needs to be done to fix its quantifiers. I suggest something
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to remain fixed), and emphasizes the hilbert transform even more. One also does not need to mention the real and imaginary parts are square integrable, once one has been more clear about the overarching hypothesis that
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Looks good to me. I like R→C better than "on the real line" too. If one was looking for a brevity award, "complex valued" is now redundant, but especially on a wiki prone to vandalism, a little redundancy never hurt.
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I'm sorry if you found the phrasing awkward. It looked alright to me at the time (in fact, it still does). Anyway, I have changed JackSchmidt's version because I feel it obscured the punchline somehow (i.e., that
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real-valued square-integrable function ƒ". Is that what it means? If so, it shouldn't be expressed by using "where". In effect, "where" becomes an existential quantifier. But
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I don't have a problem with using the word "where" to explain notation, e.g. "where 2 is the smallest integer larger than 1" etc. But in this case I'm guessing it means "for
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The theorem states that the following conditions on a square-integrable, complex valued function
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In particular, this makes the TFAE structure clearer (originally the first condition redefines
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quantifier. They leave it as an exercise to figure out which is meant. That's obnoxious.
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is square integrable (the lead at least makes this hypothesis).
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people using the word "where" in this way intend it as a
88: 96:, where you can join the project or contribute to the 446: 312: 474: 388: 86:pages on Knowledge. If you wish to help, you can 76:This disambiguation page is within the scope of 500:and the second condition quantifies over all 8: 231:). Let me know if this is better. Thanks, 82:, an attempt to structure and organize all 19: 47: 448: 447: 445: 363: 358: 331: 325: 317: 311: 92:attached to this talk page, or visit the 32:does not require a rating on Knowledge's 369: 49: 504:, but actually one intends a specific 7: 475:{\displaystyle {\mathcal {F}}(F)(x)} 106:Knowledge:WikiProject Disambiguation 300:) in the upper half-plane such that 109:Template:WikiProject Disambiguation 38:It is of interest to the following 326: 321: 14: 422:) are real-valued functions with 273:on the real line are equivalent: 593:WikiProject Disambiguation pages 69: 51: 20: 469: 463: 460: 454: 359: 354: 339: 332: 1: 227:is the Hilbert transform of 609: 292:of a holomorphic function 79:WikiProject Disambiguation 64: 46: 570:14:15, 14 May 2008 (UTC) 555:14:11, 14 May 2008 (UTC) 523:13:45, 14 May 2008 (UTC) 247:12:06, 14 May 2008 (UTC) 214:05:13, 14 May 2008 (UTC) 198:04:45, 14 May 2008 (UTC) 112:Disambiguation articles 476: 390: 477: 391: 539:Ok. Done (I hope). 444: 310: 330: 135:This article says: 30:disambiguation page 472: 386: 370: 313: 284:) is the limit as 34:content assessment 439:Fourier transform 408:Hilbert transform 166:Hilbert transform 128: 127: 124: 123: 120: 119: 600: 551: 550: 543: 481: 479: 478: 473: 453: 452: 395: 393: 392: 387: 368: 367: 362: 335: 329: 324: 243: 242: 235: 114: 113: 110: 107: 104: 91: 73: 66: 65: 55: 48: 25: 24: 16: 608: 607: 603: 602: 601: 599: 598: 597: 583: 582: 548: 547: 541: 489: 442: 441: 357: 308: 307: 240: 239: 233: 133: 111: 108: 105: 102: 101: 87: 12: 11: 5: 606: 604: 596: 595: 585: 584: 581: 580: 579: 578: 577: 576: 575: 574: 573: 572: 530: 529: 528: 527: 526: 525: 488: 487: 471: 468: 465: 462: 459: 456: 451: 435: 399: 398: 397: 396: 385: 382: 379: 376: 373: 366: 361: 356: 353: 350: 347: 344: 341: 338: 334: 328: 323: 320: 316: 302: 301: 267: 266: 265: 264: 263: 262: 261: 252: 251: 250: 249: 217: 216: 174: 173: 171: 170: 169: 132: 129: 126: 125: 122: 121: 118: 117: 115: 103:Disambiguation 84:disambiguation 74: 62: 61: 59:Disambiguation 56: 44: 43: 37: 26: 13: 10: 9: 6: 4: 3: 2: 605: 594: 591: 590: 588: 571: 567: 563: 558: 557: 556: 552: 544: 538: 537: 536: 535: 534: 533: 532: 531: 524: 520: 516: 512: 507: 503: 499: 495: 494: 493: 492: 491: 490: 485: 482:vanishes for 466: 457: 440: 436: 433: 429: 425: 421: 417: 413: 409: 405: 401: 400: 383: 380: 377: 374: 371: 364: 351: 348: 345: 342: 336: 318: 314: 306: 305: 304: 303: 299: 295: 291: 287: 283: 279: 276: 275: 274: 272: 258: 257: 256: 255: 254: 253: 248: 244: 236: 230: 226: 221: 220: 219: 218: 215: 211: 207: 202: 201: 200: 199: 195: 191: 190:Michael Hardy 187: 183: 179: 172: 167: 163: 159: 155: 151: 147: 143: 140: 139: 138: 137: 136: 130: 116: 99: 95: 90: 89:edit the page 85: 81: 80: 75: 72: 68: 67: 63: 60: 57: 54: 50: 45: 41: 35: 31: 27: 23: 18: 17: 542:silly rabbit 510: 505: 501: 497: 483: 431: 427: 423: 419: 415: 414:), where Re( 411: 403: 297: 293: 289: 285: 281: 277: 270: 268: 234:silly rabbit 228: 224: 185: 181: 177: 175: 161: 157: 153: 149: 145: 141: 134: 94:project page 77: 40:WikiProjects 29: 562:JackSchmidt 515:JackSchmidt 206:JackSchmidt 98:discussion 430:) + i Im( 418:) and Im( 406:) is the 186:universal 182:sometimes 587:Category 486:< 0. 164:is the 410:of Re( 148:) = ƒ( 36:scale. 426:= Re( 260:like: 168:of ƒ. 152:) − i 131:Where 28:This 566:talk 549:talk 519:talk 437:The 402:−Im( 378:< 241:talk 210:talk 194:talk 178:some 589:: 568:) 553:) 521:) 434:). 327:∞ 322:∞ 319:− 315:∫ 288:→ 245:) 212:) 196:) 564:( 545:( 517:( 511:F 506:F 502:F 498:F 484:x 470:) 467:x 464:( 461:) 458:F 455:( 450:F 432:F 428:F 424:F 420:F 416:F 412:F 404:F 384:. 381:K 375:x 372:d 365:2 360:| 355:) 352:y 349:i 346:+ 343:x 340:( 337:F 333:| 298:z 296:( 294:F 290:x 286:z 282:x 280:( 278:F 271:F 237:( 229:f 225:g 208:( 192:( 162:g 158:x 156:( 154:g 150:x 146:x 144:( 142:F 100:. 42::

Index


content assessment
WikiProjects
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Disambiguation
WikiProject icon
WikiProject Disambiguation
disambiguation
edit the page
project page
discussion
Hilbert transform
Michael Hardy
talk
04:45, 14 May 2008 (UTC)
JackSchmidt
talk
05:13, 14 May 2008 (UTC)
silly rabbit
talk
12:06, 14 May 2008 (UTC)
Hilbert transform
Fourier transform
JackSchmidt
talk
13:45, 14 May 2008 (UTC)
silly rabbit
talk
14:11, 14 May 2008 (UTC)
JackSchmidt

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