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Talk:Schwarz lemma

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this says that f is a constant, and in particular |f(0)|=|f(z)|=1. Since we ask that f(0)=0 for Schwarz's lemma, this wouldn't count as one of the functions the lemma applies to. To put it another way, it doesn't matter either way whether you let the codomain be the open or closed disc, the set of
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Well this is just the hypothesis, so we can ask anything we like of f (of course that doesn't mean that such an f can exist, but for example f(z)=z, or even f(z)=0, clearly takes D to D and fixes 0). However, what would happen we did allow the
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version, so I got rid of the other, but I also added a note at the bottom about the ambiguity in the theorem statement so hopefully this doesn't happen yet again. I also note Rudin's R&C A uses yet another condition, that
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By the way I know the previous comment is more than a year old, but this might help someone in future (especially since the article let the codomain be closed in a previous revision).
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functions that are included is the same (when you take into account the f(0)=0 requirement). The same applies to the Schwarz-Pick theorem.
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Just another math undergrad here... Thanks for the page - Schwarz lemma was a result I needed when studying Hyperbolic geometry.
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D is wrong, because f transforms from open unit disk to closed unit dist (and not from open to open)
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not be contained in D) there would need to be a z such that |z|<1 but |f(z)|=1. By the
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It got changed again so that it included both conditions simultaneously. I favor the
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to be the closed unit disc? For it to be a "new" function (i.e. the
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for all z? Because we already assumed co-domain as unit disc.
15: 362: 306: 253: 220: 101:, a collaborative effort to improve the coverage of 393: 341:version I already discussed that I'm ignoring it. 333: 292: 238: 8: 402: 47: 380: 363: 361: 320: 319: 305: 278: 273: 267: 259: 254: 252: 219: 49: 19: 293:{\displaystyle ||f||_{\infty }\leq 1} 7: 95:This article is within the scope of 38:It is of interest to the following 279: 157:I think that the phrase f:D--: --> 14: 437:Low-priority mathematics articles 334:{\displaystyle f:D\to {\bar {D}}} 300:, though this is so close to the 115:Knowledge:WikiProject Mathematics 118:Template:WikiProject Mathematics 82: 72: 51: 20: 135:This article has been rated as 381: 377: 371: 364: 325: 316: 274: 268: 260: 255: 230: 1: 109:and see a list of open tasks. 432:C-Class mathematics articles 394:{\displaystyle |f(z)|\leq 1} 177:21:32, 23 January 2008 (UTC) 453: 209:13:19, 12 July 2009 (UTC) 193:maximum modulus principle 134: 67: 46: 356:Why do we need to write 351:09:09, 27 May 2012 (UTC) 239:{\displaystyle f:D\to D} 141:project's priority scale 417:20:12, 1 May 2016 (UTC) 98:WikiProject Mathematics 395: 335: 294: 240: 28:This article is rated 396: 336: 295: 241: 360: 304: 251: 218: 121:mathematics articles 391: 331: 290: 236: 90:Mathematics portal 34:content assessment 419: 407:comment added by 328: 179: 167:comment added by 155: 154: 151: 150: 147: 146: 444: 400: 398: 397: 392: 384: 367: 340: 338: 337: 332: 330: 329: 321: 299: 297: 296: 291: 283: 282: 277: 271: 263: 258: 245: 243: 242: 237: 162: 123: 122: 119: 116: 113: 92: 87: 86: 76: 69: 68: 63: 55: 48: 31: 25: 24: 16: 452: 451: 447: 446: 445: 443: 442: 441: 422: 421: 358: 357: 302: 301: 272: 249: 248: 216: 215: 201:Quietbritishjim 120: 117: 114: 111: 110: 88: 81: 61: 32:on Knowledge's 29: 12: 11: 5: 450: 448: 440: 439: 434: 424: 423: 390: 387: 383: 379: 376: 373: 370: 366: 354: 353: 327: 324: 318: 315: 312: 309: 289: 286: 281: 276: 270: 266: 262: 257: 235: 232: 229: 226: 223: 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: 449: 438: 435: 433: 430: 429: 427: 420: 418: 414: 410: 406: 388: 385: 374: 368: 352: 348: 344: 322: 313: 310: 307: 287: 284: 264: 233: 227: 224: 221: 213: 212: 211: 210: 206: 202: 197: 194: 190: 186: 180: 178: 174: 170: 169:86.152.31.253 166: 159: 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: 403:— Preceding 355: 343:75.76.162.89 198: 181: 160: 156: 137:Low-priority 136: 96: 62:Low‑priority 40:WikiProjects 409:103.27.8.45 163:—Preceding 112:Mathematics 103:mathematics 59:Mathematics 426:Categories 405:unsigned 185:codomain 165:unsigned 139:on the 30:C-class 36:scale. 189:image 413:talk 347:talk 205:talk 173:talk 131:Low 428:: 415:) 386:≤ 349:) 326:¯ 317:→ 285:≤ 280:∞ 231:→ 207:) 175:) 411:( 389:1 382:| 378:) 375:z 372:( 369:f 365:| 345:( 323:D 314:D 311:: 308:f 288:1 275:| 269:| 265:f 261:| 256:| 234:D 228:D 225:: 222:f 203:( 171:( 143:. 42::

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86.152.31.253
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21:32, 23 January 2008 (UTC)
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09:09, 27 May 2012 (UTC)
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