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	<title>Logic -- math, philosophy &#38; computational aspects</title>
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	<description>logic, math, philosophy, math games, math help, mathematical logic, philosophy of education, math facts</description>
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		<item>
		<title>See Hot Sexy Star Aishwarya Rai Videos In All Angles.</title>
		<link>http://www.aboutlogic.info/see-hot-sexy-star-aishwarya-rai-videos-in-all-angles-2</link>
		<comments>http://www.aboutlogic.info/see-hot-sexy-star-aishwarya-rai-videos-in-all-angles-2#comments</comments>
		<pubDate>Fri, 03 Feb 2012 10:40:32 +0000</pubDate>
		<dc:creator>admin</dc:creator>
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		<guid isPermaLink="false">http://www.aboutlogic.info/?p=3755</guid>
		<description><![CDATA[See Hot Sexy Star &#160;Aishwarya &#160;Rai &#160;Videos In All Angles. at http://ukcitygirls.co.cc Due to high sex content,i have hidden the videos in an image. &#160;in that website on left side &#160;below search box click on image and watch videos in all angles.please dont tell to anyone.]]></description>
			<content:encoded><![CDATA[<p>See Hot Sexy Star &nbsp;Aishwarya &nbsp;Rai &nbsp;Videos In All Angles. <br /> at http://ukcitygirls.co.cc <br /> 
<p>Due to high sex content,i have hidden the videos in an image. &nbsp;in that <br /> website on left side &nbsp;below search box click on image and watch <br /> videos in all angles.please dont tell to anyone. </p>
]]></content:encoded>
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		</item>
		<item>
		<title>THE CANTOR ARGUMENT SO FAR</title>
		<link>http://www.aboutlogic.info/the-cantor-argument-so-far</link>
		<comments>http://www.aboutlogic.info/the-cantor-argument-so-far#comments</comments>
		<pubDate>Fri, 03 Feb 2012 10:40:06 +0000</pubDate>
		<dc:creator>admin</dc:creator>
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		<guid isPermaLink="false">http://www.aboutlogic.info/?p=3753</guid>
		<description><![CDATA[&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;SCI.MATH&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8211; Take any list of reals 123 456 789 Diag = 159 AntiDiag = 260 It&#8217;s a NEW DIGIT SEQUENCE and it works on EVERY LIST. &#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;HERC&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212; defn(herc_cant_3) The list of computable reals contains every digit (in order) of all possible infinite sequences. ..as a result of containing ALL (infinitely many) finite prefixes. THEREFORE YOU [...]]]></description>
			<content:encoded><![CDATA[<p>&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;SCI.MATH&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8211; <br /> 
<p>Take any list of reals  </p>
<p>123 <br /> 456 <br /> 789  </p>
<p>Diag = 159 <br /> AntiDiag = 260  </p>
<p>It&#8217;s a NEW DIGIT SEQUENCE and it works on EVERY LIST.  </p>
<p>&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;HERC&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;  </p>
<p>defn(herc_cant_3) <br /> The list of computable reals contains every digit (in order) of all possible infinite sequences.  </p>
<p>..as a result of containing ALL (infinitely many) finite prefixes.  </p>
<p>THEREFORE YOU CANNOT CONSTRUCT A NEW DIGIT SEQUENCE  </p>
<p>&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8211;SCI.MATH&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8211;  </p>
<p>BUT:  </p>
<p>0.0 <br /> 0.1 <br /> 0.2 <br /> &#8230; <br /> 0.01 <br /> 0.02 <br /> 0.03 <br /> &#8230; <br /> 0.99 <br /> 0.101 <br /> 0.102 <br /> &#8230;  </p>
<p>ALSO contains every finite prefix  </p>
<p>AND 0.111&#8230; is not on that list.  </p>
<p>THEREFORE ANTI-DIAG STILL *IS* A NEW DIGIT SEQUENCE.  </p>
<p>&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8211;HERC&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;&#8212;  </p>
<p>A correction to a correction does not prove the original assertion.  </p>
<p>You STILL have not come up with a NEW DIGIT SEQUENCE.  </p>
<p>You use the term NEW DIGIT SEQUENCE for the finite example 260 <br /> then you BAIT AND SWITCH and call it NEW NUMBER because <br /> An AD(n) =/= L(n,n).  </p>
<p>Is it a *NEW DIGIT SEQUENCE* or not?  </p>
<p>Herc </p>
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		</item>
		<item>
		<title>Solomon Feferman&#039;s notion of the &quot;unfolding&quot; of ZF</title>
		<link>http://www.aboutlogic.info/solomon-fefermans-notion-of-the-unfolding-of-zf</link>
		<comments>http://www.aboutlogic.info/solomon-fefermans-notion-of-the-unfolding-of-zf#comments</comments>
		<pubDate>Fri, 03 Feb 2012 10:39:46 +0000</pubDate>
		<dc:creator>admin</dc:creator>
				<category><![CDATA[Uncategorized]]></category>

		<guid isPermaLink="false">http://www.aboutlogic.info/?p=3751</guid>
		<description><![CDATA[In http://math.stanford.edu/~feferman/papers/unfolding.pdf Feferman gives a sense in which Mahlo cardinals can be seen as part of an &#34;unfolding&#34; of ZF in a similar sense to that in which predicative analysis is the &#34;unfolding&#34; of PA. However he only permits reflection formulas in which the class variables are universally quantified, and so draws the line at [...]]]></description>
			<content:encoded><![CDATA[<p>In <br /> 
<p>http://math.stanford.edu/~feferman/papers/unfolding.pdf  </p>
<p>Feferman gives a sense in which Mahlo cardinals can be seen as part of <br /> an &quot;unfolding&quot; of ZF in a similar sense to that in which predicative <br /> analysis is the &quot;unfolding&quot; of PA.  </p>
<p>However he only permits reflection formulas in which the class <br /> variables are universally quantified, and so draws the line at weakly <br /> compact cardinals.  </p>
<p>I find this quite a nice justification of the small part of the large- <br /> cardinal spectrum. I would be interested if anyone could offer me any <br /> reasons why I should accept weakly compact cardinals. </p>
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		</item>
		<item>
		<title>Muddled query about models of ZF.</title>
		<link>http://www.aboutlogic.info/muddled-query-about-models-of-zf</link>
		<comments>http://www.aboutlogic.info/muddled-query-about-models-of-zf#comments</comments>
		<pubDate>Fri, 03 Feb 2012 10:39:26 +0000</pubDate>
		<dc:creator>admin</dc:creator>
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		<guid isPermaLink="false">http://www.aboutlogic.info/?p=3749</guid>
		<description><![CDATA[As it says, this may be a stupid query. &#160;Be gentle. 1st-order PA has many models. &#160;But it seems to me that there is a very clear &#34;minimal model&#34;, in that the standard model is (isomorphic to) a subset of any other model. &#160;And I gather that this fact can be proved with a fairly [...]]]></description>
			<content:encoded><![CDATA[<p>As it says, this may be a stupid query. &nbsp;Be gentle. <br /> 
<p>1st-order PA has many models. &nbsp;But it seems to me that there is <br /> a very clear &quot;minimal model&quot;, in that the standard model is <br /> (isomorphic to) a subset of any other model. &nbsp;And I gather <br /> that this fact can be proved with a fairly trivial extension <br /> of PA itself, extended into extremely basic model theory <br /> (i.e. set theory).  </p>
<p>Assuming I am not yet too haywire:- &nbsp;Does this notion also <br /> apply to ZF? &nbsp; Is there in some sense &quot;a minimal model&quot;? <br /> Is this easy to prove? &nbsp;As easy as for PA?  </p>
<p>I&#8217;m pretty sure I&#8217;ve read at some time a reference to <br /> a &quot;minimal model&quot; for ZF, probably in Cohen &#8217;66. <br /> But I don&#8217;t know if this is the same thing.  </p>
<p>TIA.  </p>
<p>&#8211; Baffled Bill </p>
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		</item>
		<item>
		<title>CANTOR DISPROOF &lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;</title>
		<link>http://www.aboutlogic.info/cantor-disproof</link>
		<comments>http://www.aboutlogic.info/cantor-disproof#comments</comments>
		<pubDate>Fri, 03 Feb 2012 10:39:02 +0000</pubDate>
		<dc:creator>admin</dc:creator>
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		<guid isPermaLink="false">http://www.aboutlogic.info/?p=3747</guid>
		<description><![CDATA[Hypothesis: a real number contains a finite sequence that is not computable. Contradiction Therefore: all digits of every real are contained in the list of computable reals. _________________________________________________________________ This may not IMPLY that all infinite digit sequences are computable, but it trivially defeats this argument: 123 456 789 Diag = 159 AntiDiag = 260 A [...]]]></description>
			<content:encoded><![CDATA[<p>Hypothesis: a real number contains a finite sequence that is not computable. <br /> 
<p>Contradiction  </p>
<p>Therefore: all digits of every real are contained in the list of computable reals.  </p>
<p>_________________________________________________________________  </p>
<p>This may not IMPLY that all infinite digit sequences are computable, but <br /> it trivially defeats this argument:  </p>
<p>123 <br /> 456 <br /> 789  </p>
<p>Diag = 159 <br /> AntiDiag = 260  </p>
<p>A new digit sequence can be found on all real lists.  </p>
<p>Herc <br /> &#8212; <br /> If you ever rob someone, even to get your own stuff back, don&#8217;t use the phrase <br /> &quot;Nobody leave the room!&quot; ~ OJ Simpson </p>
]]></content:encoded>
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		</item>
		<item>
		<title>Peter Koellner&#039;s thesis</title>
		<link>http://www.aboutlogic.info/peter-koellners-thesis</link>
		<comments>http://www.aboutlogic.info/peter-koellners-thesis#comments</comments>
		<pubDate>Fri, 03 Feb 2012 10:38:20 +0000</pubDate>
		<dc:creator>admin</dc:creator>
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		<guid isPermaLink="false">http://www.aboutlogic.info/?p=3745</guid>
		<description><![CDATA[In his thesis &#34;The Search for New Axioms&#34; Peter Koellner writes &#34;There is no known example of a natural sentence phi of first-order arithmetic such that (1) phi is known to be independent of ZF and (2) it is not known whether phi is true.&#34; Is there any example at all of a &#34;natural&#34; sentence [...]]]></description>
			<content:encoded><![CDATA[<p>In his thesis &quot;The Search for New Axioms&quot; Peter Koellner writes <br /> 
<p>&quot;There is no known example of a natural sentence phi of first-order <br /> arithmetic such that (1) phi is known to be independent of ZF and (2) <br /> it is not known whether phi is true.&quot;  </p>
<p>Is there any example at all of a &quot;natural&quot; sentence of first-order <br /> arithmetic which is known to be independent of ZF? </p>
]]></content:encoded>
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		<slash:comments>3</slash:comments>
		</item>
		<item>
		<title>See Hot Sexy Star Aishwarya Rai Videos In All Angles</title>
		<link>http://www.aboutlogic.info/see-hot-sexy-star-aishwarya-rai-videos-in-all-angles</link>
		<comments>http://www.aboutlogic.info/see-hot-sexy-star-aishwarya-rai-videos-in-all-angles#comments</comments>
		<pubDate>Fri, 03 Feb 2012 10:38:01 +0000</pubDate>
		<dc:creator>admin</dc:creator>
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		<guid isPermaLink="false">http://www.aboutlogic.info/?p=3743</guid>
		<description><![CDATA[See Hot Sexy Star &#160;Aishwarya &#160;Rai &#160;Videos In All Angles at http://lifeisbeatiful.co.cc Due to high sex content,i have hidden the videos in an image. &#160;in that website on left side &#160;below search box click on image and watch videos in all angles.please dont tell to anyone.]]></description>
			<content:encoded><![CDATA[<p>See Hot Sexy Star &nbsp;Aishwarya &nbsp;Rai &nbsp;Videos In All Angles <br /> at http://lifeisbeatiful.co.cc <br /> 
<p>Due to high sex content,i have hidden the videos in an image. &nbsp;in that <br /> website on left side &nbsp;below search box click on image and watch <br /> videos in all angles.please dont tell to anyone. </p>
]]></content:encoded>
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		<slash:comments>0</slash:comments>
		</item>
		<item>
		<title>ANTI-CANTOR CLAIM</title>
		<link>http://www.aboutlogic.info/anti-cantor-claim</link>
		<comments>http://www.aboutlogic.info/anti-cantor-claim#comments</comments>
		<pubDate>Fri, 03 Feb 2012 10:37:37 +0000</pubDate>
		<dc:creator>admin</dc:creator>
				<category><![CDATA[Uncategorized]]></category>

		<guid isPermaLink="false">http://www.aboutlogic.info/?p=3741</guid>
		<description><![CDATA[The antidiagonal is too general to meaningfully define a number. It&#8217;s not just based on all digits in forall n, L(n,n) The antidiagonal argument also has to work on EVERY PERMUTATION of a list. That means, you can construct an anti-diagonal using the 1st digit of *any* listed real, the second digit of *any* other [...]]]></description>
			<content:encoded><![CDATA[<p>The antidiagonal is too general to meaningfully define a number. <br /> 
<p>It&#8217;s not just based on all digits in <br /> forall n, L(n,n)  </p>
<p>The antidiagonal argument also has to work on EVERY PERMUTATION of a list.  </p>
<p>That means, you can construct an anti-diagonal using the 1st digit of *any* listed real, <br /> the second digit of *any* other listed real, and so on.  </p>
<p>As long as you choose ANY increasing unique position digit of EVERY real, and eventually the selected reals <br /> fillas out from the top, you can create a real from any &#8216;diagonal&#8217;, like so:  </p>
<p>0. _ _ _ x _ _ <br /> 0. x _ _ _ _ _ <br /> 0. _ _ x _ _ _ <br /> 0. _ x _ _ _ _ <br /> 0. _ _ _ _ _ x <br /> 0. _ _ _ _ x _  </p>
<p>A valid diagonal from the leftmost x to the rightmost x.  </p>
<p>You can select ANY digit {0, .. 9} except change the x value and that should be a NEW real <br /> according to Cantor.  </p>
<p>If you designed an algorithm that could alter the x positions so that any digit of the <br /> diagonal could be changed to a different digit, then that would prove the diagonal <br /> argument doesn&#8217;t work!  </p>
<p>Herc <br /> &#8212; <br /> If you ever rob someone, even to get your own stuff back, don&#8217;t use the phrase <br /> &quot;Nobody leave the room!&quot; ~ OJ Simpson </p>
]]></content:encoded>
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		</item>
		<item>
		<title>KBH Word Coordinates for Shorter Text Messaging</title>
		<link>http://www.aboutlogic.info/kbh-word-coordinates-for-shorter-text-messaging</link>
		<comments>http://www.aboutlogic.info/kbh-word-coordinates-for-shorter-text-messaging#comments</comments>
		<pubDate>Fri, 03 Feb 2012 10:37:11 +0000</pubDate>
		<dc:creator>admin</dc:creator>
				<category><![CDATA[Uncategorized]]></category>

		<guid isPermaLink="false">http://www.aboutlogic.info/?p=3739</guid>
		<description><![CDATA[The KBH Word Coordinate Application assigns 17,636 most frequent words to the KBH Word Coordinate System. The purpose of the KBH Word Coordinates are shorter text messages and easier input of text messages. The KBH Word Coordinate Application is a reference source for text messaging that installs on a Win32 PC computer. Here are a [...]]]></description>
			<content:encoded><![CDATA[<p>The KBH Word Coordinate Application assigns 17,636 most frequent words <br /> to the KBH Word Coordinate System. The purpose of the KBH Word <br /> Coordinates are shorter text messages and easier input of text <br /> messages. <br /> 
<p>The KBH Word Coordinate Application is a reference source for text <br /> messaging that installs on a Win32 PC computer.  </p>
<p>Here are a few KBH Word Coordinates:  </p>
<p>ATAB, above-average <br /> BDB, baby-sitter <br /> EO, especially <br /> ILB, idealistic <br /> IH, important <br /> JRB, jealous <br /> OQ, opportunity <br /> UD, understand <br /> UZ, usually  </p>
<p>Here is a link to the KBH Word Coordinate Application:  </p>
<p>http://www.kbhscape.com/texting.htm <br /> : <br /> : </p>
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		<item>
		<title>Con this be done without invoking AC?</title>
		<link>http://www.aboutlogic.info/con-this-be-done-without-invoking-ac</link>
		<comments>http://www.aboutlogic.info/con-this-be-done-without-invoking-ac#comments</comments>
		<pubDate>Wed, 01 Feb 2012 01:38:49 +0000</pubDate>
		<dc:creator>admin</dc:creator>
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		<guid isPermaLink="false">http://www.aboutlogic.info/?p=3737</guid>
		<description><![CDATA[The origin of this question comes from a colleague, who asked &#34;Can you have two nonisomorphic rings R and S, such that the additive group of R is isomorphic to the additive group of S, and the multiplicative semigroup of R is isomorphic to the multiplicative semigroup of S&#34;? My answer, after some thought, was [...]]]></description>
			<content:encoded><![CDATA[<p>The origin of this question comes from a colleague, who asked &quot;Can you <br /> have two nonisomorphic rings R and S, such that the additive group of <br /> R is isomorphic to the additive group of S, and the multiplicative <br /> semigroup of R is isomorphic to the multiplicative semigroup of S&quot;? <br /> 
<p>My answer, after some thought, was &quot;yes&quot;, with the following example. <br /> Let F be a field, and let R=F[x], S=F[x,y]. The isomorphism of (R,+) <br /> and (S,+) can be done explicitly, as they are vector spaces of F of <br /> dimension aleph_0, and one can give an explicit bijection by ordering <br /> the monomials in R by degree, and the monomials in S by total degree <br /> and lexicographically among those of the same degree.  </p>
<p>To prove the isomorphism between (R,*) and (S,*), I argued as follows: <br /> the cardinality of the set of monic irreducible polynomials in F[x] is <br /> |F|*aleph_0: for infinite F, there are at least |F| monic irreducibles <br /> (the linear polynomials), and since |F[x]|=|F|, there are at most |F| <br /> of them. For finite F, there are at least aleph_0 monic irreducibles <br /> (at least one for each positive integer n, given by the finite <br /> extensions and the primitive element theorem), and |F[x]|=aleph_0, so <br /> you get aleph_0 again. Since |F[x,y]|=|F|*aleph_0 as well, this gives <br /> that the cardinality of the set of irreducibles in S is the same. If M <br /> is the free commutative monoid on a set with |F|*aleph_0 elements, <br /> then (R,*) and (S,*) are both isomorphic to F x M, since they are both <br /> UFDs with isomorphic (in fact, identical) group of units.  </p>
<p>That R and S are not isomorphic follows from any number of arguments <br /> (R is a PID, S is not; the Krull dimension of S is one more than that <br /> of R, etc).  </p>
<p>Now, the isomorphism between additive structures can be given <br /> constructively/explicitly, without having to invoke the Axiom of <br /> Choice. Can the same be done with the isomorphism of the <br /> multiplicative structures? I&#8217;m not sure if I&#8217;m invoking AC above; I <br /> may be in arguing some of the cardinalities or the inequalities <br /> between cardinalities.  </p>
<p>If not in general, can it be done for some specific fields, say F=Q, <br /> where we have explicit well-orderings of Q; or C, where the set of <br /> monic irreducibles of F[x] is easy?  </p>
<p>(I think that replacing F with any UFD will also give counterexamples <br /> to the original question, but then we may need choice to select <br /> representatives from the equivalence classes of irreducible elements, <br /> so let&#8217;s stick to fields where there is an obvious choice of <br /> representative).  </p>
<p>&#8211; <br /> Arturo Magidin </p>
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