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basis without essentially using AC for some cardinal. However, there is no reason why it should say Zorn's lemma instead of the axiom of choice, and the point is largely irrelevant for functional analysis, as there are very few cases where one actually needs a Hamel basis for a particular infinite-dimensional Banach space.
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3. "For any real number p ≥ 1, an example of a Banach space is given by "all Lebesgue-measurable functions whose absolute value's p-th power has finite integral" (see Lp spaces)" ("Banch spaces" paragraph) Since this sentence is supposed to present an example of Banch space for a general audience, I
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5."geometry of Banach spaces, a combinatorial approach as in the work of Jean Bourgain" (in "Points of view"). The study of geometry of Banach spaces requires much more than combinatorics. Also, the study was initiated by Fritz-Johnes and Dvoretzky work and then developed into "theory" by works of
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I fixed the remark saying that Hahn-Banach requires AC. Hahn-Banach can only be side-stepped in separable spaces if one allows DC. The comment about infinite-dimensional spaces is correct, I would think, because almost all spaces actually considered in functional analysis can not be shown to have a
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There are two versions, with ISBNs 978-2100493364 and 978-2100043149. Unfortunately, none of the book finder links in wikipedia's book finder seem to work, and it's not on amazon.com, but both versions may be found at amazon.ca, and the former may be found at amazon.fr. Go figure. However, I still
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2. "There is no clear definition of what would constitute a base, for example" (very next sentence). This is definetely not true. The notion of a base in Banach spaces is well defined and understood, see any text book on Functional Analysis. Moreover, this sentence seems to relate somehow to its
118:. I'm sure much of this is wrong, and much of the rest is POV. Some infinite-dimensional spaces can be shown to have a basis without AC, surely. Hahn-Banach can be side-stepped in separable spaces. And the advice is not necessarily good. Is any of this really important to keep? 293:
Functional Analysis is also a well known term in Applied Behavior Analysis (a branch of psychology) and concerns the analysis of the function of a particular behavior, especially problem or maladaptive behaviors. I would suggest a cross reference to Applied Behavior Analysis.
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I am unaware of a singel case of a Banch space which requires use of Zorn's lemma to show that it has a basis.Usually, a basic sequence is "more or less a natural choice" and the prove is focused on showing that, indeed, the sequence forms a basis.
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In the article it was said that "every operator on a Hilbert space has a proper subspace which is invariant". Now is invariant some functional theoretic term or is that invariant under some transformation? I'm not an expert on FA.
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1."General Banach spaces are more complicated." (in "Banach spaces" paragraph) I assume that this relates Hilber and Banach spaces. This is a type of "apples or bananas" issue and there is no need to try to resolve it here.
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V.Milman (and others). I am not trying to take anything from outstanding work of J. Bourgain, I am just saying that this part of the article contains two misleading references.
169: 208:. By the way, you should not use the minor edit checkmark for edits which are not minor, like for example starting a new topic on talk pages. Also, it is good to use 301: 274: 244:
would suggest that l^p (or C) be used instead of L^p. I mean, one would not have to invoke concept of Lebesgue mesaurable functions.
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predicessor and suggests that Banch spaces are so difficult to understand that people do not even know how to define a base.
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2."The Volume of Convex Bodies and Banach Space Geometry " by by Gilles Pisier,ISBN: 0521364655 ,Cambridge University Press
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6. References section. It contains references to books at least 50 years old. I suggest that the following be added:
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1. "Classical Banach spaces" by Joram Lindenstrauss, Lior Tzafriri, ISBN: 3540606289, Springer 1996
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4."To show the existence of a vector space basis for such spaces may require Zorn's lemma"
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I have a few comments about wording and substance of a few claims raised in this article:
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Is it really kind to give the three volumes of Dunford and Schwartz as basic reference?
209: 139:"Since finite-dimensional Hilbert spaces are fully understood in linear algebra (...)" 108: 142:
That's not completely true. In fact, very much is unknown even about the geometry of
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If you wish to start a new discussion or revive an old one, please do so on the
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Functional Analysis is also an important part of Applied Behavior Analysis
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The following discussion relates to a now abandoned proposal to
25: 250:(Second sentence in "Foundation of mathematics" paragraph) 99:, my man, these subjects diverged nearly a century ago. 148: 212:, so that others can tell what you changed. Thanks. 163: 8: 316:ISBN for Analyse Fonctionnelle by H. Brezis 295: 268: 155: 151: 150: 147: 44:Do not edit the contents of this page. 7: 204:I fixed that, I believe it is about 24: 164:{\displaystyle \mathbb {R} ^{3}} 91:should this page be merged with 29: 188: 1: 222:00:05, 19 February 2006 (UTC) 199:19:31, 18 February 2006 (UTC) 128:02:56, 4 December 2005 (UTC) 107:I'm inclined to agree here. 341: 326:17:46, 26 March 2007 (UTC) 321:think it's worth listing. 283:17:52, 23 March 2006 (UTC) 185:18:42, 23 Nov 2004 (UTC) 177:15:16, 2004 Nov 23 (UTC) 136:19:38, 8 Sep 2004 (UTC) 103:07:56, 5 Sep 2003 (UTC) 18:Talk:Functional analysis 310:01:50, 5 May 2006 (UTC) 189:I don't understand this 111:08:01, 5 Sep 2003 (UTC) 165: 93:calculus of variations 81:calculus of variations 166: 42:of past discussions. 146: 206:invariant subspace 161: 116:Additional remarks 79:this article with 312: 300:comment added by 285: 273:comment added by 67: 66: 54: 53: 48:current talk page 332: 228:================ 183:Charles Matthews 170: 168: 167: 162: 160: 159: 154: 134:Charles Matthews 101:Charles Matthews 63: 56: 55: 33: 32: 26: 340: 339: 335: 334: 333: 331: 330: 329: 318: 291: 251: 230: 214:Oleg Alexandrov 191: 149: 144: 143: 72: 59: 30: 22: 21: 20: 12: 11: 5: 338: 336: 317: 314: 290: 287: 249: 229: 226: 225: 224: 210:edit summaries 190: 187: 179: 158: 153: 131: 130: 113: 112: 71: 68: 65: 64: 52: 51: 34: 23: 15: 14: 13: 10: 9: 6: 4: 3: 2: 337: 328: 327: 324: 315: 313: 311: 307: 303: 302:24.62.102.153 299: 288: 286: 284: 280: 276: 272: 265: 262: 259: 255: 248: 245: 241: 237: 233: 227: 223: 219: 215: 211: 207: 203: 202: 201: 200: 197: 186: 184: 178: 176: 172: 156: 140: 137: 135: 129: 126: 121: 120: 119: 117: 110: 106: 105: 104: 102: 98: 94: 90: 85: 84: 82: 78: 69: 62: 58: 57: 49: 45: 41: 40: 35: 28: 27: 19: 319: 296:— Preceding 292: 275:12.149.111.4 269:— Preceding 266: 263: 260: 256: 252: 246: 242: 238: 234: 231: 196:Matikkapoika 192: 180: 173: 141: 138: 132: 115: 114: 88: 86: 74: 73: 60: 43: 37: 36:This is an 125:Cwzwarich 109:Dysprosia 61:Archive 1 298:unsigned 271:unsigned 87:Really, 39:archive 323:Althai 89:no way 70:Merge? 175:mbork 77:merge 16:< 306:talk 279:talk 218:talk 97:Phys 95:. 308:) 281:) 220:) 194:-- 171:! 304:( 277:( 216:( 157:3 152:R 83:. 50:.

Index

Talk:Functional analysis
archive
current talk page
Archive 1
merge
calculus of variations
calculus of variations
Phys
Charles Matthews
Dysprosia
Cwzwarich
02:56, 4 December 2005 (UTC)
Charles Matthews
mbork
Charles Matthews
Matikkapoika
19:31, 18 February 2006 (UTC)
invariant subspace
edit summaries
Oleg Alexandrov
talk
00:05, 19 February 2006 (UTC)
unsigned
12.149.111.4
talk
17:52, 23 March 2006 (UTC)
unsigned
24.62.102.153
talk
01:50, 5 May 2006 (UTC)

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