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Talk:Cofinality

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is aleph-null. And so is the cardinality of the obvious co-final subset which is the natural numbers (which are well-ordered). But one could also choose the cofinal subset to be the integers themselves (after all, B is cofinal in itself, right?), since they also have cardinality aleph-null which is the cofinality. And the integers are not well-ordered, contrary to the sentence. Also the integers are not order-isomorhpic to the natural numbers, again contrary to the sentence.
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Which is true? If they are always the same due to properties of cardinalities, it is better to use "min" than "inf", since "inf" implies that a limit must be taken whereas "min" just picks the smallest element, which is then assumed to exist. If they are not the same, then I believe the textual definition should be corrected to use the infimum.
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your point is taken, when we use the word "cofinality" we are usually talking about only a least cardinality (and only apropos a cardinal number), where as with the word "cofinal" we may talk about any set inside any poset. The latter usage is different. I still say merge though. But let's hear what others think as well. -
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However, if the right argument is zero or a successor (such as the "3" in your example), then this does not work because continuous functions are λ-continuous for any infinite regular ordinal λ, but neither 0-continuous nor 1-continuous in general. (But multiplication is 0-continuous; and addition is
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again, "Trichotomy: If two sets are given, then they either have the same cardinality, or one has a smaller cardinality than the other." is one of the theorems which are equivalent to the axiom. In other words, without the axiom there are pairs of cardinal numbers which are incomparable -- neither is
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OK. I see that I was failing to read the second sentence in the context of the first sentence, "If A admits a totally ordered cofinal subset, then we can find a subset B which is well-ordered and cofinal in A.", which says that that B is well-ordered. So the integers would not be a counter-example,
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I've reorganized the article a bit. I moved the definition of regular and singular into the lead. I added some content to the "Examples" section (please double check my additions), and moved that section to follow immediately after the lead (I think it helps to have examples as soon as possible). And
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Yeah, I was thinking of cardinals as some least ordinal, and well ordering of ordinals is built into their definitions. But of course, that definition of cardinals relies on AC. And the proof of well ordering in the general case also requires AC. I knew that stuff, but the reason I was momentarily
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In the section "Cofinality of cardinals", the text says "cf(κ) = the cardinality of the smallest collection of sets of strictly smaller cardinals whose sum is κ". But the equation directly following it defines it as the infimum, i.e. a greatest lower bound rather than the least element from the set.
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It is written : "This definition of cofinality relies on the axiom of choice, as it uses the fact that every non-empty set of cardinal numbers has a least member" Isn't it always true by the well ordering of the ordinals that every set of ordinals has a minimum ? Why do one need the axiom of choice
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fit them logically into separate articles is not as relevant to me as whether a single merged article would be too long. I think the answer to the latter question is "no", and hence I support the merger. I also note that having separate articles for the noun and the adjective is a bad policy. But
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The second sentence, "Moreover, any cofinal subset of B whose cardinality is equal to the cofinality of B is well-ordered, and these sets are all order isomorphic.", in the section "Properties" seems (to me) to be incorrect. Let us take B to be the Integers with the usual order. Their cardinality
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It's not that your browser is defective, but rather that your system doesn't have a unicode enabled font with that symbol. As far as using math tags, I never use math tags for inline math text. I'm fighting hard not to revert your changes, I've seen others do the same revert. But I try to remind
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confused was because well-ordering really means two things: least element, and totalness of ordering. I somehow thought that sentence meant that you need AC to prove every cardinal has a least element, which is certainly not true. But I was just being dumb. Anyway, thanks for the clarification. -
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The second paragraph of the lead includes "... the axiom of choice is assumed ... in the rest of this article ...". Consequently, the cardinal numbers are a subclass of the ordinal numbers and thus well-ordered. The infimum of any nonempty subclass of a well-ordered class exists and is a member of
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For certain infinite sets X, it is also possible to avoid the axiom of choice. For example, suppose that the elements of X are sets of natural numbers. Every nonempty set of natural numbers has a least element, so to specify our choice function we can simply say that it takes each set to the least
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I guess I was wrong about this being a unicode font issue. I guess the real issue is that Internet Explorer is broken. I don't like making Knowledge (or the web in general) cater to the bugs of Microsoft, but it's unrealistic to expect to be able to not support IE when it constitutes 90% of the
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It has a codepoint of x2135, part of the block of "letterlike symbols". This is a different glyph from the Hebrew letter. But anyway, if you don't have it, you don't have it. I didn't revert you, but I don't agree with your argument. If we insist on everything being readable in every single
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For what it's worth, I use IE 6 SP 2, and Firefox 1.5.0.1, and I see the "you don't have this character" box in IE, but I see the aleph-lookalike glyph in Firefox. I hypothesize that it's so much a font thing, since both programs surely access the same pool of fonts, as a browser
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element of that set. This gives us a definite choice of an element from each set and we can write down an explicit expression that tells us what value our choice function takes. Any time it is possible to specify such an explicit choice, the axiom of choice is unnecessary.
232:, so in particular the cardinality of the continuum has uncountable cofinality. I don't see how the countable union of countable sets is relevant here, and I suspect this is a mistake based on assuming CH (as I've seen mistakes of this nature on Knowledge before). -- 204:
How does the countable union of countable sets help in establishing that cf(card(R)) is uncountable? Without CH we don't know that sets smaller than R are countable - so maybe we can get R with a countable union of uncountable sets which still are smaller than R.
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Even if I can find a better unicode font than I have or get a Hebrew language package, that would only solve the problem for ME. Surely there are many other readers out there who only see square boxes when you-all use those characters.
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Yes, I feel that we must support IE by avoiding the use of those small alephs. Now that I have down-loaded Firefox, I checked that the characters which I replaced were in fact alephs, which they were as I had inferred from the context.
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can be well-ordered. This is true of all cardinals, of course, but the proof requires AC. (As with many articles, this one is a mess as regards AC - sometimes mentioning when it is needed, and at other times silently assuming it.)
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This depends on your definition of a cardinal. You can define cardinals such that cardinals are well-ordered independent of choice, but the drawback is that it is then possible to have sets with undefined cardinality.
1188:, as it relies on the fact that every non-empty set of cardinal numbers has a least number." - The first emplies it uses the axiom of choice, but actualy it avoids using it because you are making an explicit choice. - 389: 245:
Thanks for pointing out the proof to me, I agree with your suspicion - assuming CH clearly rules out card(R) = aleph_omega, which was the question I had when I found this page ;). I edited the article accordingly.
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Like the user at 151.200.whatever (who is probably my nephew Edward), I could not read the small alephs in Internet Explorer, but now that I am using Firefox (without any change in fonts), they are clear.
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No, it relies on the Axiom of Choice. The explicit choice is the choice of the least member of a non-empty set of cardinals. You are right that we don't need the Axiom of Choice to pick this least member
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Thank you for clarifying that! Suggest, then, to change "inf" to "min", since "inf" implies a more complicated operation (which in this case ends up just yielding the minimum).
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Hmm... maybe what is meant is not that cardinals need not be well-founded, but rather that they need not be totally ordered. If we don't assume AC, that is. -
1665: 130: 995:. Now I am not sure about the merge anymore. I think that enough could be said about the properties of cofinal subsets to justify separate articles. -- 1547:
Without the axiom of choice there are non-wellorderable sets. Their cardinal numbers do not have initial ordinals. So you cannot sort them that way,
164:"Moreover, any cofinal subset of B whose cardinality is equal to the cofinality of B is well-ordered and order isomorphic to its own cardinality." 106: 1660: 333: 1635: 1601: 1532: 166:
Is this correct? I don't think so... The last part "order isomorphic to its own cardinality." would imply that B is a cardinal?! Anyone?
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Countable union of countable sets is countable - this requires at least the Countable Axiom of Choice, as far as I know. Correct?
785:") which just looks like a square-box to me. And I do not think that my browser is defective. Why? If it is supposed to be an 221: 1271:
Are there any rules to compute the cofinality of the sum, product or power of ordinals? For example, what is the cofinality of
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since they are not well-ordered. Still, the second sentence is hard to understand. Could it be expanded to make it clearer?
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market or whatever. It's unreasonable to tell everyone who wants to view wikipedia to get a different web browser, right? -
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cf(κ) = the cardinality of the smallest collection of sets of strictly smaller cardinals such that their sum is κ
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should redirect there. There's a lot to be said about regular cardinals that goes far beyond their cofinality. --
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I'm not necessarily against a merge, but if they're merged I feel strongly that the article should be at
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myself that not everyone has a capable computer. Please do consider getting some unicode fonts though. -
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Right now there is a certain asymmetry between the content on regular cardinals and regular ordinals:
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If we do not merge, then I think that "Cofinal (mathematics)" should be renamed "Cofinal subset".
509:κ for all κ<λ (inductive hypothesis), then I can take the union of both sides and have union {ℵ 105:
on Knowledge. If you would like to participate, please visit the project page, where you can join
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Wow. Easy enough to see, but still surprising. I added a section about aleph fixed points to
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Isn't every cardinal well-ordered? In particular, isn't 0 a least element of every cardinal? -
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What is your method of making an "explicit choice" and so avoiding the axiom of choice?
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Hmm.. let's go through that a little more carefully. Let δ be a limit ordinal. Then ℵ
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is always greater than δ, while cf(δ) ≤ δ. Therefore, this statement implies that no
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are continuous and strictly increasing in the right argument. Thus the cofinality of
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Yup, that sentence didn't make sense. I think I have it stated correctly now.--
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Agreed, "sets of" seems superfluous. Also, the '=' should be replaced by 'is'.
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IMHO it should be changed to: "This definition of cofinality avoids using the
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union {κ: κ<λ}. But that operation probably isn't valid. For instance,
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the subclass. So "infimum" and "minimum" mean the same thing in this case.
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This section was copied with minor changes from the Knowledge article on
384:{\displaystyle \mathrm {cf} (\aleph _{\delta })=\mathrm {cf} (\delta )} 1214:. The trouble is that without the Axiom of Choice it may not exist. -- 1643: 1625: 1609: 1584: 1556: 1540: 1513: 1340: 1260: 1239: 1218: 1192: 1171: 1116: 1098: 1063: 1044: 1027: 1014: 999: 982: 955: 944: 929: 890: 880: 869: 852: 842: 832: 822: 811: 766: 753: 540: 407: 311: 282: 272: 255: 236: 214: 194: 177: 1403:{\displaystyle \omega ^{\omega +42}+\omega ^{2}+\omega \cdot 3\,} 1324:{\displaystyle \omega ^{\omega +42}+\omega ^{2}+\omega \cdot 3\,} 504:
OK, I think that might be a problem. I use the fact that if ℵ
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is a limit cardinal iff δ is a limit ordinal. And I think ℵ
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is a limit cardinal. Then, according to the article, cf(ℵ
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exists. Somethings not right. Or am I mucking it up? -
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I'm a bit of a mergist by heart. So whether or not we
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I titled the remaining content "Properties". Comments?
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be any cardinal number, and for each positive integer
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Yes. One uses the fact that the binary operations of
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By a "well-orderable cardinal", it means a cardinal
101:, a collaborative effort to improve the coverage of 695:{\displaystyle \kappa _{n}=\aleph _{\kappa _{n-1}}} 1492: 1470: 1448: 1402: 1323: 797: 741: 714: 694: 641: 621: 594: 561: 383: 264:For any infinite well-orderable cardinal number κ? 838:browser, we'll never be able to move forward. - 459:λ (this last by inductive assumption). Since ℵ 1235:smaller than the other nor are they the same. 917:New section on cofinality of well-ordered sets 898: 463:≥ λ, it must also be greater than λ+1, since ℵ 8: 526:, but if you take the union, you get ω : --> 326:The article says: "one can prove that for a 1070:Merge "regular cardinal" into "cofinality"? 781:You-all are using a character (in "think ℵ 47: 1483: 1461: 1415: 1380: 1361: 1355: 1301: 1282: 1276: 790: 733: 727: 707: 678: 673: 660: 654: 634: 613: 607: 595:{\displaystyle \delta =\aleph _{\delta }} 586: 574: 554: 364: 352: 337: 335: 1086:has its own (very short) article. Maybe 1488: 1466: 1456:which is the same as the cofinality of 1444: 1398: 1319: 777:decipherability of unicode aleph symbol 49: 19: 437:is strictly greater than λ, for all λ. 228:< cf(2) for any infinite cardinal 190:Correct, I added a mention of that.-- 7: 1059:, which is the more used concept. -- 95:This article is within the scope of 1573:Why do we need 'sets of' in there? 987:I have removed the overlap between 805:, then you should use <math: --> 38:It is of interest to the following 1666:High-priority mathematics articles 962:Merge "cofinal" with "cofinality"? 899:I've reorganized the article a bit 792: 670: 583: 368: 365: 349: 341: 338: 14: 1410:is the same as the cofinality of 295:such that any set of cardinality 115:Knowledge:WikiProject Mathematics 1567:Does this have excess words: --> 532:So maybe it's possible to have ℵ 322:every limit cardinal is singular 118:Template:WikiProject Mathematics 82: 72: 51: 20: 200:Why is cf(card(R)) uncountable? 135:This article has been rated as 483:Now if λ is a limit ordinal, ℵ 442:For a successor ordinal λ+1, ℵ 421:) = cf(δ). cf(δ) ≤ δ, so cf(ℵ 378: 372: 358: 345: 1: 1644:14:11, 13 November 2014 (UTC) 1626:09:01, 13 November 2014 (UTC) 1610:15:02, 12 November 2014 (UTC) 1230:As a matter of fact, quoting 912:16:51, 21 February 2006 (UTC) 195:10:36, 22 December 2005 (UTC) 178:11:05, 22 December 2005 (UTC) 109:and see a list of open tasks. 1661:B-Class mathematics articles 767:10:54, 1 February 2006 (UTC) 754:09:42, 1 February 2006 (UTC) 541:09:38, 1 February 2006 (UTC) 408:08:51, 1 February 2006 (UTC) 312:14:30, 31 January 2006 (UTC) 283:12:51, 31 January 2006 (UTC) 273:12:49, 31 January 2006 (UTC) 256:13:47, 11 January 2006 (UTC) 1240:03:48, 18 August 2006 (UTC) 1219:20:09, 17 August 2006 (UTC) 1193:19:00, 17 August 2006 (UTC) 1172:02:45, 17 August 2006 (UTC) 742:{\displaystyle \kappa _{n}} 722:be the supremum of all the 622:{\displaystyle \kappa _{0}} 391:". But I have a problem: ℵ 237:14:26, 3 January 2006 (UTC) 215:23:03, 2 January 2006 (UTC) 1682: 1585:22:03, 13 March 2014 (UTC) 1520:Relying on axiom of choice 956:07:13, 21 March 2006 (UTC) 945:12:16, 19 March 2006 (UTC) 930:07:48, 18 March 2006 (UTC) 891:10:33, 26 March 2006 (UTC) 881:09:22, 25 March 2006 (UTC) 870:09:02, 25 March 2006 (UTC) 853:02:32, 22 March 2006 (UTC) 843:08:18, 21 March 2006 (UTC) 833:07:18, 21 March 2006 (UTC) 823:14:06, 19 March 2006 (UTC) 812:12:25, 19 March 2006 (UTC) 450:{all ords of cardinality ℵ 429:is regular, then we have ℵ 1557:20:00, 30 June 2012 (UTC) 1541:16:30, 30 June 2012 (UTC) 1514:05:40, 4 April 2009 (UTC) 1493:{\displaystyle \omega \,} 1471:{\displaystyle \omega \,} 1341:20:25, 3 April 2009 (UTC) 1267:Arithmetics of cofinality 1261:00:11, 13 July 2010 (UTC) 170:21:21, 30 Mar 2005 (UTC) 162:There is this statement: 134: 67: 46: 1117:14:58, 7 July 2006 (UTC) 1108:should be expanded, and 1099:11:49, 7 July 2006 (UTC) 1064:14:57, 7 July 2006 (UTC) 1045:07:45, 7 July 2006 (UTC) 1028:06:47, 7 July 2006 (UTC) 1015:21:24, 6 July 2006 (UTC) 1000:20:48, 6 July 2006 (UTC) 983:20:30, 6 July 2006 (UTC) 549:There are many ordinals 433:≤ δ. But I claim that ℵ 183:Countable choice needed? 141:project's priority scale 798:{\displaystyle \aleph } 715:{\displaystyle \delta } 562:{\displaystyle \delta } 98:WikiProject Mathematics 1494: 1472: 1450: 1404: 1325: 1090:should be merged into 799: 743: 716: 696: 643: 623: 596: 563: 385: 28:This article is rated 1495: 1473: 1451: 1405: 1326: 993:cofinal (mathematics) 972:cofinal (mathematics) 800: 744: 717: 697: 644: 624: 597: 564: 467:is a limit ordinal, ℵ 401:inaccessible cardinal 386: 1482: 1460: 1414: 1354: 1275: 974:, I say absolutely. 935:Error in Properties? 806:\aleph</math: --> 789: 726: 706: 653: 633: 606: 573: 553: 334: 121:mathematics articles 602:. For example, let 158:Incoherent sentence 1490: 1489: 1468: 1467: 1446: 1445: 1400: 1399: 1348:ordinal arithmetic 1321: 1320: 795: 739: 712: 692: 639: 619: 592: 559: 381: 90:Mathematics portal 34:content assessment 1595:Least vs. infimum 1531:comment added by 1251:comment added by 1161: 1148:comment added by 642:{\displaystyle n} 155: 154: 151: 150: 147: 146: 1673: 1543: 1499: 1497: 1496: 1491: 1477: 1475: 1474: 1469: 1455: 1453: 1452: 1447: 1409: 1407: 1406: 1401: 1385: 1384: 1372: 1371: 1330: 1328: 1327: 1322: 1306: 1305: 1293: 1292: 1263: 1143: 1106:regular cardinal 1096:Tobias Bergemann 1088:regular cardinal 1084:regular cardinal 1042:Tobias Bergemann 997:Tobias Bergemann 804: 802: 801: 796: 748: 746: 745: 740: 738: 737: 721: 719: 718: 713: 701: 699: 698: 693: 691: 690: 689: 688: 665: 664: 648: 646: 645: 640: 628: 626: 625: 620: 618: 617: 601: 599: 598: 593: 591: 590: 568: 566: 565: 560: 513:: κ<λ} : --> 499:{κ: κ<λ} = λ. 495:: κ<λ} : --> 390: 388: 387: 382: 371: 357: 356: 344: 220:It follows from 123: 122: 119: 116: 113: 92: 87: 86: 76: 69: 68: 63: 55: 48: 31: 25: 24: 16: 1681: 1680: 1676: 1675: 1674: 1672: 1671: 1670: 1651: 1650: 1597: 1565: 1526: 1522: 1504:1-continuous.) 1480: 1479: 1458: 1457: 1412: 1411: 1376: 1357: 1352: 1351: 1297: 1278: 1273: 1272: 1269: 1246: 1232:axiom of choice 1186:axiom of choice 1132:Axiom of choice 1125: 1110:regular ordinal 1076:regular ordinal 1072: 964: 937: 923:ordinal numbers 919: 901: 787: 786: 784: 779: 729: 724: 723: 704: 703: 674: 669: 656: 651: 650: 631: 630: 609: 604: 603: 582: 571: 570: 551: 550: 535: 522:for all finite 512: 507: 494: 486: 476: 470: 466: 462: 457: 453: 445: 436: 432: 428: 424: 420: 416: 398: 394: 348: 332: 331: 324: 266: 252:129.187.111.179 222:König's Theorem 202: 185: 160: 120: 117: 114: 111: 110: 88: 81: 61: 32:on Knowledge's 29: 12: 11: 5: 1679: 1677: 1669: 1668: 1663: 1653: 1652: 1649: 1648: 1647: 1646: 1636:130.225.98.243 1629: 1628: 1602:212.242.115.68 1596: 1593: 1592: 1591: 1564: 1561: 1560: 1559: 1533:79.182.240.117 1521: 1518: 1517: 1516: 1501: 1487: 1478:which is just 1465: 1443: 1440: 1437: 1434: 1431: 1428: 1425: 1422: 1419: 1397: 1394: 1391: 1388: 1383: 1379: 1375: 1370: 1367: 1364: 1360: 1318: 1315: 1312: 1309: 1304: 1300: 1296: 1291: 1288: 1285: 1281: 1268: 1265: 1228: 1227: 1226: 1225: 1224: 1223: 1222: 1221: 1200: 1199: 1198: 1197: 1196: 1195: 1177: 1176: 1175: 1174: 1141: 1140: 1124: 1123:Is this right? 1121: 1120: 1119: 1071: 1068: 1067: 1066: 1052: 1051: 1050: 1049: 1048: 1047: 1033: 1032: 1031: 1030: 1018: 1017: 966:about merging 963: 960: 959: 958: 936: 933: 918: 915: 900: 897: 896: 895: 894: 893: 862: 861: 860: 859: 858: 857: 856: 855: 850:151.200.185.98 807:to create it. 794: 782: 778: 775: 774: 773: 772: 771: 770: 769: 736: 732: 711: 687: 684: 681: 677: 672: 668: 663: 659: 638: 616: 612: 589: 585: 581: 578: 558: 544: 543: 533: 529: 528: 510: 505: 501: 500: 492: 484: 480: 479: 474: 468: 464: 460: 455: 451: 443: 439: 438: 434: 430: 426: 422: 418: 414: 396: 392: 380: 377: 374: 370: 367: 363: 360: 355: 351: 347: 343: 340: 323: 320: 319: 318: 317: 316: 315: 314: 286: 285: 265: 262: 261: 260: 259: 258: 240: 239: 211:84.151.224.202 201: 198: 192:Luke Gustafson 184: 181: 175:Luke Gustafson 168:82.157.131.133 159: 156: 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: 1678: 1667: 1664: 1662: 1659: 1658: 1656: 1645: 1641: 1637: 1633: 1632: 1631: 1630: 1627: 1623: 1619: 1614: 1613: 1612: 1611: 1607: 1603: 1594: 1589: 1588: 1587: 1586: 1582: 1578: 1577:173.25.54.191 1574: 1571: 1568: 1562: 1558: 1554: 1550: 1546: 1545: 1544: 1542: 1538: 1534: 1530: 1519: 1515: 1511: 1507: 1502: 1485: 1463: 1441: 1438: 1435: 1432: 1429: 1426: 1423: 1420: 1417: 1395: 1392: 1389: 1386: 1381: 1377: 1373: 1368: 1365: 1362: 1358: 1349: 1345: 1344: 1343: 1342: 1338: 1334: 1316: 1313: 1310: 1307: 1302: 1298: 1294: 1289: 1286: 1283: 1279: 1266: 1264: 1262: 1258: 1254: 1253:24.196.91.135 1250: 1242: 1241: 1238: 1233: 1220: 1217: 1213: 1208: 1207: 1206: 1205: 1204: 1203: 1202: 1201: 1194: 1191: 1187: 1183: 1182: 1181: 1180: 1179: 1178: 1173: 1170: 1166: 1165: 1164: 1163: 1162: 1159: 1155: 1151: 1147: 1137: 1136: 1135: 1133: 1128: 1122: 1118: 1115: 1111: 1107: 1103: 1102: 1101: 1100: 1097: 1093: 1089: 1085: 1081: 1078:redirects to 1077: 1069: 1065: 1062: 1058: 1054: 1053: 1046: 1043: 1039: 1038: 1037: 1036: 1035: 1034: 1029: 1026: 1022: 1021: 1020: 1019: 1016: 1013: 1008: 1004: 1003: 1002: 1001: 998: 994: 990: 985: 984: 981: 977: 973: 969: 961: 957: 954: 949: 948: 947: 946: 943: 934: 932: 931: 928: 924: 916: 914: 913: 910: 907: 892: 889: 884: 883: 882: 879: 874: 873: 872: 871: 868: 854: 851: 846: 845: 844: 841: 836: 835: 834: 831: 826: 825: 824: 821: 816: 815: 814: 813: 810: 776: 768: 765: 761: 757: 756: 755: 752: 734: 730: 709: 685: 682: 679: 675: 666: 661: 657: 636: 614: 610: 587: 579: 576: 556: 548: 547: 546: 545: 542: 539: 531: 530: 525: 521: 517: 503: 502: 498: 490: 482: 481: 449: 441: 440: 412: 411: 410: 409: 406: 402: 375: 361: 353: 329: 328:limit ordinal 321: 313: 310: 305: 304: 303: 298: 294: 290: 289: 288: 287: 284: 281: 277: 276: 275: 274: 271: 263: 257: 253: 249: 244: 243: 242: 241: 238: 235: 231: 227: 223: 219: 218: 217: 216: 212: 208: 199: 197: 196: 193: 188: 182: 180: 179: 176: 171: 169: 165: 157: 142: 138: 137:High-priority 132: 129: 128: 125: 108: 104: 100: 99: 91: 85: 80: 78: 75: 71: 70: 66: 62:High‑priority 60: 57: 54: 50: 45: 41: 35: 27: 23: 18: 17: 1598: 1575: 1572: 1569: 1566: 1527:— Preceding 1525:for that ? 1523: 1270: 1243: 1229: 1212:if it exists 1211: 1142: 1129: 1126: 1104:No, I think 1073: 1006: 986: 975: 965: 938: 920: 902: 863: 780: 760:aleph number 523: 519: 515: 496: 488: 447: 425:) ≤ δ. If ℵ 325: 296: 292: 267: 229: 225: 203: 189: 186: 172: 163: 161: 136: 96: 40:WikiProjects 1247:—Preceding 1144:—Preceding 1040:I agree. — 906:Paul August 702:, then let 112:Mathematics 103:mathematics 59:Mathematics 1655:Categories 1092:cofinality 1080:cofinality 1057:cofinality 989:cofinality 968:cofinality 569:for which 248:SirJective 207:SirJective 1618:JRSpriggs 1549:JRSpriggs 1506:JRSpriggs 1237:JRSpriggs 1169:JRSpriggs 1114:Trovatore 1061:Trovatore 1025:JRSpriggs 953:JRSpriggs 942:JRSpriggs 927:JRSpriggs 888:JRSpriggs 867:JRSpriggs 830:JRSpriggs 809:JRSpriggs 472:λ ==: --> 1529:unsigned 1249:unsigned 1158:contribs 1146:unsigned 518:+1 : --> 1563:Wording 1500:itself. 1333:Albmont 1216:Zundark 976:support 751:Zundark 302:Zundark 234:Zundark 139:on the 30:B-class 1082:while 848:thing. 36:scale. 1190:Drysh 1150:Drysh 1130:From 1012:lethe 1007:could 980:lethe 970:with 878:lethe 840:lethe 820:lethe 764:lethe 538:lethe 508:: --> 497:union 489:union 477:: --> 471:: --> 458:: --> 454:} ≥ ℵ 448:union 405:lethe 309:lethe 280:lethe 270:lethe 224:that 1640:talk 1622:talk 1606:talk 1581:talk 1553:talk 1537:talk 1510:talk 1337:talk 1257:talk 1154:talk 1094:. — 991:and 749:. -- 649:let 478:λ+1. 131:High 978:. - 475:λ+1 469:λ+1 465:λ+1 461:λ+1 444:λ+1 1657:: 1642:) 1624:) 1608:) 1583:) 1555:) 1539:) 1512:) 1486:ω 1464:ω 1442:ω 1436:ω 1430:ω 1421:⋅ 1418:ω 1393:⋅ 1390:ω 1378:ω 1369:42 1363:ω 1359:ω 1339:) 1331:? 1314:⋅ 1311:ω 1299:ω 1290:42 1284:ω 1280:ω 1259:) 1160:) 1156:• 1134:: 925:. 793:ℵ 731:κ 710:δ 683:− 676:κ 671:ℵ 658:κ 611:κ 588:δ 584:ℵ 577:δ 557:δ 527:ω. 491:{ℵ 487:= 446:= 376:δ 354:δ 350:ℵ 330:δ 300:-- 254:) 246:-- 213:) 205:-- 1638:( 1620:( 1604:( 1579:( 1551:( 1535:( 1508:( 1439:+ 1433:+ 1427:= 1424:3 1396:3 1387:+ 1382:2 1374:+ 1366:+ 1335:( 1317:3 1308:+ 1303:2 1295:+ 1287:+ 1255:( 1152:( 909:☎ 783:δ 735:n 686:1 680:n 667:= 662:n 637:n 615:0 580:= 534:λ 524:n 520:n 516:n 511:κ 506:κ 493:κ 485:λ 473:ℵ 456:λ 452:λ 435:λ 431:δ 427:δ 423:δ 419:δ 415:δ 397:δ 393:δ 379:) 373:( 369:f 366:c 362:= 359:) 346:( 342:f 339:c 297:k 293:k 250:( 230:k 226:k 209:( 143:. 42::

Index


content assessment
WikiProjects
WikiProject icon
Mathematics
WikiProject icon
icon
Mathematics portal
WikiProject Mathematics
mathematics
the discussion
High
project's priority scale
82.157.131.133
Luke Gustafson
11:05, 22 December 2005 (UTC)
Luke Gustafson
10:36, 22 December 2005 (UTC)
SirJective
84.151.224.202
23:03, 2 January 2006 (UTC)
König's Theorem
Zundark
14:26, 3 January 2006 (UTC)
SirJective
129.187.111.179
13:47, 11 January 2006 (UTC)
lethe
12:49, 31 January 2006 (UTC)
lethe

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