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	<title>Comments on: Guest post: Alejandro Rivero, &#8220;sBootstrap&#8221;</title>
	<atom:link href="http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/feed/" rel="self" type="application/rss+xml" />
	<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/</link>
	<description>private thoughts of a physicist and chessplayer</description>
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		<item>
		<title>By: Alejandro Rivero</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-94970</link>
		<dc:creator>Alejandro Rivero</dc:creator>
		<pubDate>Mon, 10 Mar 2008 14:42:59 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-94970</guid>
		<description>Hi T.
Perhaps the comment in #32 is an important advance. I was thinking today: if we admit that the only possible arrangement of these degrees of freedom is as &quot;coloured&quot; Majorana fermions, then it seems that they truncate themselves out, because QCD is vector like. The usual folklore about the need for the neutrino to be neutral.
On other hand, allowing for this chiral beasties and its truncation would force similar forgiveness in the equations of the main argument, clouding it :-(
To resume, I need more time to understand what is going on with chirality, and I haven got any, at least until the summer.</description>
		<content:encoded><![CDATA[<p>Hi T.<br />
Perhaps the comment in #32 is an important advance. I was thinking today: if we admit that the only possible arrangement of these degrees of freedom is as &#8220;coloured&#8221; Majorana fermions, then it seems that they truncate themselves out, because QCD is vector like. The usual folklore about the need for the neutrino to be neutral.<br />
On other hand, allowing for this chiral beasties and its truncation would force similar forgiveness in the equations of the main argument, clouding it <img src='http://s.wordpress.com/wp-includes/images/smilies/icon_sad.gif' alt=':-(' class='wp-smiley' /><br />
To resume, I need more time to understand what is going on with chirality, and I haven got any, at least until the summer.</p>
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	<item>
		<title>By: dorigo</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-94391</link>
		<dc:creator>dorigo</dc:creator>
		<pubDate>Wed, 27 Feb 2008 07:39:42 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-94391</guid>
		<description>Hi Alejandro,

thank you for keeping this thread updated. I will visit the physicsforum thread this weekend.

Cheers,
T.</description>
		<content:encoded><![CDATA[<p>Hi Alejandro,</p>
<p>thank you for keeping this thread updated. I will visit the physicsforum thread this weekend.</p>
<p>Cheers,<br />
T.</p>
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	<item>
		<title>By: Alejandro Rivero</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-94384</link>
		<dc:creator>Alejandro Rivero</dc:creator>
		<pubDate>Wed, 27 Feb 2008 00:16:36 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-94384</guid>
		<description>Hi,

There is also an aproved &quot;independent research&quot; thread in physicsforums, to discuss the topic of this thread. No posts at this moment, but some people could prefer to use the BBoard system insted of Blog comments
http://www.physicsforums.com/showthread.php?t=172821

I really think that string theory could help with the most troublesome problem of this approach: to interpret the pairs cc, cu and uu, which are not obviously forbidden, forming three (and times color) degres of freedom with no obvious arrangement as Dirac fermions, and pretty exotic electric charge. They could be arranged in three chiral (and charged!) fermions, but then they are massless and can not be uplifted to the mass of the top quark. The hope is that the mechanism barring these particles out of existence is forced to be a chirality argument and then it introduces chirality in sBootstrap. 

a related meditation is pure numerology: that the main numbers of string theory revolve around 8 and 24, with some secondary numbers being 26, 10, 10/2=5, and 2^5=32.   The sBootstrap approach seems to visit similar places.</description>
		<content:encoded><![CDATA[<p>Hi,</p>
<p>There is also an aproved &#8220;independent research&#8221; thread in physicsforums, to discuss the topic of this thread. No posts at this moment, but some people could prefer to use the BBoard system insted of Blog comments<br />
<a href="http://www.physicsforums.com/showthread.php?t=172821" rel="nofollow">http://www.physicsforums.com/showthread.php?t=172821</a></p>
<p>I really think that string theory could help with the most troublesome problem of this approach: to interpret the pairs cc, cu and uu, which are not obviously forbidden, forming three (and times color) degres of freedom with no obvious arrangement as Dirac fermions, and pretty exotic electric charge. They could be arranged in three chiral (and charged!) fermions, but then they are massless and can not be uplifted to the mass of the top quark. The hope is that the mechanism barring these particles out of existence is forced to be a chirality argument and then it introduces chirality in sBootstrap. </p>
<p>a related meditation is pure numerology: that the main numbers of string theory revolve around 8 and 24, with some secondary numbers being 26, 10, 10/2=5, and 2^5=32.   The sBootstrap approach seems to visit similar places.</p>
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	<item>
		<title>By: dorigo</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78875</link>
		<dc:creator>dorigo</dc:creator>
		<pubDate>Wed, 24 Oct 2007 09:17:37 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78875</guid>
		<description>Hi Alejandro,

funny how you are being drawn to some of ST&#039;s ideas by your own theory. I think it is a very interesting convergence. Keep working at it!

Cheers,
T.</description>
		<content:encoded><![CDATA[<p>Hi Alejandro,</p>
<p>funny how you are being drawn to some of ST&#8217;s ideas by your own theory. I think it is a very interesting convergence. Keep working at it!</p>
<p>Cheers,<br />
T.</p>
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	<item>
		<title>By: Alejandro Rivero</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78814</link>
		<dc:creator>Alejandro Rivero</dc:creator>
		<pubDate>Tue, 23 Oct 2007 23:31:32 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78814</guid>
		<description>At the kind requeriment of the owner of this blog, Woit &lt;a href=&quot;http://www.math.columbia.edu/~woit/wordpress/?p=612#comment-29830&quot; rel=&quot;nofollow&quot;&gt;answers&lt;/a&gt; about supersymmetry putting the finger in the ttraditional problem: how to break it. Our idea here still lacks of a mechanism, but it should be very different from the usual ones, specially if we want the leptons to meet Koide; it should imply that most of the breaking is mixing between QCD objects, leaving leptons untouched. 
On the other hand, about compositeness and dynamics, we have already a part of the dynamics: QCD. The problem is the compositeness or not of the gauge bosons. Here we start to approach string theory, imagining a W boson as the result of joining the extremes of a charged meson to form a closed string. Because of this I explicitly asked Dorigo to stress, in the introduction above, that I do not like string theory. I have always been against it, and now the perversion of being forced into its use gives me mixed feelings, the more positive being that if it works here it probably disproves or discourages its use at Planck scale.</description>
		<content:encoded><![CDATA[<p>At the kind requeriment of the owner of this blog, Woit <a href="http://www.math.columbia.edu/~woit/wordpress/?p=612#comment-29830" rel="nofollow">answers</a> about supersymmetry putting the finger in the ttraditional problem: how to break it. Our idea here still lacks of a mechanism, but it should be very different from the usual ones, specially if we want the leptons to meet Koide; it should imply that most of the breaking is mixing between QCD objects, leaving leptons untouched.<br />
On the other hand, about compositeness and dynamics, we have already a part of the dynamics: QCD. The problem is the compositeness or not of the gauge bosons. Here we start to approach string theory, imagining a W boson as the result of joining the extremes of a charged meson to form a closed string. Because of this I explicitly asked Dorigo to stress, in the introduction above, that I do not like string theory. I have always been against it, and now the perversion of being forced into its use gives me mixed feelings, the more positive being that if it works here it probably disproves or discourages its use at Planck scale.</p>
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	<item>
		<title>By: Cavendish experiment 3 at Freedom of Science</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78441</link>
		<dc:creator>Cavendish experiment 3 at Freedom of Science</dc:creator>
		<pubDate>Sun, 21 Oct 2007 19:50:14 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78441</guid>
		<description>[...] Tommaso Dorigo advises to approach orthodoxy on a negotiations basis. (See comments to this post.) [...]</description>
		<content:encoded><![CDATA[<p>[...] Tommaso Dorigo advises to approach orthodoxy on a negotiations basis. (See comments to this post.) [...]</p>
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		<title>By: Alejandro Rivero</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78205</link>
		<dc:creator>Alejandro Rivero</dc:creator>
		<pubDate>Sat, 20 Oct 2007 00:51:01 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78205</guid>
		<description>Thanks, I have checked it now and it is actually clearer than some preprints of the UAM I had got to read (Zwiebach says that his example clones or follows some others from the Spanish group of strings, which is mostly around the Universidad Autonoma; regretly I have not relationship with them, but I was considering to ask some students I knew).</description>
		<content:encoded><![CDATA[<p>Thanks, I have checked it now and it is actually clearer than some preprints of the UAM I had got to read (Zwiebach says that his example clones or follows some others from the Spanish group of strings, which is mostly around the Universidad Autonoma; regretly I have not relationship with them, but I was considering to ask some students I knew).</p>
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		<title>By: kneemo</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78188</link>
		<dc:creator>kneemo</dc:creator>
		<pubDate>Fri, 19 Oct 2007 21:10:15 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78188</guid>
		<description>Alejandro, for a clear discussion on quarks and string-brane configurations, see 15.6 and 15.7 of Barton Zwiebach&#039;s string theory &lt;a href=&quot;http://www.amazon.com/First-Course-String-Theory/dp/0521831431&quot; rel=&quot;nofollow&quot;&gt;book&lt;/a&gt;.  There he constructs an intersecting brane model on T^6 (6-torus) which closely resembles the standard model, but also mentions the more subtle issues that arise such as electroweak symmetry breaking and the non-uniqueness of the brane configuration.</description>
		<content:encoded><![CDATA[<p>Alejandro, for a clear discussion on quarks and string-brane configurations, see 15.6 and 15.7 of Barton Zwiebach&#8217;s string theory <a href="http://www.amazon.com/First-Course-String-Theory/dp/0521831431" rel="nofollow">book</a>.  There he constructs an intersecting brane model on T^6 (6-torus) which closely resembles the standard model, but also mentions the more subtle issues that arise such as electroweak symmetry breaking and the non-uniqueness of the brane configuration.</p>
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		<title>By: Alejandro Rivero</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78153</link>
		<dc:creator>Alejandro Rivero</dc:creator>
		<pubDate>Fri, 19 Oct 2007 14:56:19 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78153</guid>
		<description>About using string theory for the simplest mesons, the problem is how to calculate the decay rates, which should be proportional to m^3 or to m^5. This is because the strong decay channels are closed. 

Now, decay rate has units of mass (or energy, if you wish). A theory without dimensional constants can only produce a mass dependence m^1.  If the theory contains some fundamental scales La Lb Lc etc, then you can combine them to get different depencences. Ten dimensional string theory has a lot of these: the string scale, to start with, plus the compactification scale in each compact direction. 

If you only consider the simplest combinations, only with the string scale A,  of dimension [M^-2], then you can get a mass dependence in two ways: either A/M, or M^3/A.  We need the later, but amusingly most of the papers on &quot;string decay&quot; like to consider the former, simply because it is the most paradoxical (the lifetime increases with M!).</description>
		<content:encoded><![CDATA[<p>About using string theory for the simplest mesons, the problem is how to calculate the decay rates, which should be proportional to m^3 or to m^5. This is because the strong decay channels are closed. </p>
<p>Now, decay rate has units of mass (or energy, if you wish). A theory without dimensional constants can only produce a mass dependence m^1.  If the theory contains some fundamental scales La Lb Lc etc, then you can combine them to get different depencences. Ten dimensional string theory has a lot of these: the string scale, to start with, plus the compactification scale in each compact direction. </p>
<p>If you only consider the simplest combinations, only with the string scale A,  of dimension [M^-2], then you can get a mass dependence in two ways: either A/M, or M^3/A.  We need the later, but amusingly most of the papers on &#8220;string decay&#8221; like to consider the former, simply because it is the most paradoxical (the lifetime increases with M!).</p>
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	<item>
		<title>By: Alejandro Rivero</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78149</link>
		<dc:creator>Alejandro Rivero</dc:creator>
		<pubDate>Fri, 19 Oct 2007 14:41:24 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78149</guid>
		<description>Indeed thank very much. Althought I hope the casual readers will notice this is “amateur science in the making”; profesional science is done by a sequence of setting and answering problems inspired in the problems already solved or hinted by your advisor and your peers.</description>
		<content:encoded><![CDATA[<p>Indeed thank very much. Althought I hope the casual readers will notice this is “amateur science in the making”; profesional science is done by a sequence of setting and answering problems inspired in the problems already solved or hinted by your advisor and your peers.</p>
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	<item>
		<title>By: kneemo</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78104</link>
		<dc:creator>kneemo</dc:creator>
		<pubDate>Fri, 19 Oct 2007 09:02:46 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78104</guid>
		<description>Thank you for the words of support Tommaso.</description>
		<content:encoded><![CDATA[<p>Thank you for the words of support Tommaso.</p>
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		<title>By: dorigo</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78088</link>
		<dc:creator>dorigo</dc:creator>
		<pubDate>Fri, 19 Oct 2007 06:58:11 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78088</guid>
		<description>Sounds like a great title, Carl. I&#039;m confident the body will match my expectations.
Cheers,
T.</description>
		<content:encoded><![CDATA[<p>Sounds like a great title, Carl. I&#8217;m confident the body will match my expectations.<br />
Cheers,<br />
T.</p>
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		<title>By: dorigo</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78084</link>
		<dc:creator>dorigo</dc:creator>
		<pubDate>Fri, 19 Oct 2007 06:25:52 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78084</guid>
		<description>Hi all,

I shall not comment on the many interesting contributions to the discussion above, but I wish to thank all who are contributing to it. It is &quot;science in the making&quot; and I am glad this creative process is taking place here.

Cheers,
T.</description>
		<content:encoded><![CDATA[<p>Hi all,</p>
<p>I shall not comment on the many interesting contributions to the discussion above, but I wish to thank all who are contributing to it. It is &#8220;science in the making&#8221; and I am glad this creative process is taking place here.</p>
<p>Cheers,<br />
T.</p>
]]></content:encoded>
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	<item>
		<title>By: carlbrannen</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78056</link>
		<dc:creator>carlbrannen</dc:creator>
		<pubDate>Fri, 19 Oct 2007 01:51:55 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78056</guid>
		<description>Tommaso, I&#039;ll type up a post tentatively titled &quot;4 magnificent papers by authors who think I&#039;m a complete idiot&quot;.</description>
		<content:encoded><![CDATA[<p>Tommaso, I&#8217;ll type up a post tentatively titled &#8220;4 magnificent papers by authors who think I&#8217;m a complete idiot&#8221;.</p>
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	<item>
		<title>By: Doug</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78007</link>
		<dc:creator>Doug</dc:creator>
		<pubDate>Thu, 18 Oct 2007 18:57:43 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-78007</guid>
		<description>Hi Alejandro,

I have only a limited understanding of “... “Regge trajectories”: a dependence between energy and angular momentum ...’, from papers such as the following.

D. A. Kulikov, R. S. Tutik. Renormalization of expansions for Regge trajectories of the Schrödinger equation 
http://arxiv.org/ftp/quant-ph/papers/0609/0609066.pdf

other Tutik papers
http://arxiv.org/find/all/1/all:+tutik/0/1/0/all/0/1

This comment may be an over generalization, focusing on my perceived importance trajectories.
I speculate that the importance of trajectories as a “dynamic” dimension or degree of freedom has been overlooked in physics.
The classical 3 spatial dimensions, whether complex, real or “imaginary”, are essentially static on some type of coordinate system, whether commutative or non-commutative, polar or Euclidian.
Trajectory sets may include the sum of all paths with some paths more optimal subsets than others and may be non-commutative even in a commutative coordinate system.
Consider the travel of spacecraft from Earth to Mars and back.
A trajectory from planetary bodies in relative motion with coordinates centered on E0: E0 to M1 on M2 return to E3 where E is Earth, M is Mars and 0,1,2,3 are the relative coordinate positions at times 0, 1, 2, 3.
E0 ....... E1 .................... E2 ................ E3
From to M1 ... when ............... when
when ............. on M1 to M2 ... from to M3
M0....... M1 ................... M2 ............... M3
The simultaneous trajectory from M0 to E1 on E2 back to M3 is not commutative.

On an Earth roadmaps the relative positions of Start to Finish do not change but many trajectory routes are available; not all are optimal.

A reason I discuss this is that I suspect that physics is not using all the mathematical tools available to engineering. These disciplines are historically related.
Just as CP Steinmetz used phasor equation based upon Grassmann Algebra in electrical engineering about 25-30 years before ERJA  Schrodinger used Hamiltonian equations based upon Clifford Algebra in quantum mechanics; today engineers are using dynamic game theory and variants in robotics to correlate electrical calculations with mechanical movements. This is somewhat like naval gunnery using the electronics of fire control radar to operate the mechanical ballistics [trajectory] of gunfire.

The SIAM classic Basar and Olsder, Dynamic Noncooperative Game Theory (Classics in Applied Mathematics), is very complicated mathematics leading to pursuit evasion games.
Paul J Nahin has easy to read engineering based books on extrema and pursuit evasion games: 
1- Dr. Euler&#039;s Fabulous Formula: Cures Many Mathematical Ills, 
2 - When Least Is Best: How Mathematicians Discovered Many Clever Ways to Make Things as Small (or as Large) as Possible, 
3 - Chases and Escapes: The Mathematics of Pursuit and Evasion.
 
There are more flexible, dioid, idempotent “tropical” variants of this type of mathematics.
I am most familiar with Max Plus Algebra. I have not found a blog on this subject. There is a web homepage. There are many ArXiv articles with Stéphane Gaubert of INRIA among the more prominent authors. 
Geert Jan Olsder with others has written Max Plus Algebra as an introductory text.
 
There are other engineering books that I need to read to better understand applied as opposed to theoretical mathematical solutions.
Much of this material may indirectly be related to John Conway and his work on game theory. I do hope to one day complete  ‘On Quaternions and Octonions’.</description>
		<content:encoded><![CDATA[<p>Hi Alejandro,</p>
<p>I have only a limited understanding of “&#8230; “Regge trajectories”: a dependence between energy and angular momentum &#8230;’, from papers such as the following.</p>
<p>D. A. Kulikov, R. S. Tutik. Renormalization of expansions for Regge trajectories of the Schrödinger equation<br />
<a href="http://arxiv.org/ftp/quant-ph/papers/0609/0609066.pdf" rel="nofollow">http://arxiv.org/ftp/quant-ph/papers/0609/0609066.pdf</a></p>
<p>other Tutik papers<br />
<a href="http://arxiv.org/find/all/1/all:+tutik/0/1/0/all/0/1" rel="nofollow">http://arxiv.org/find/all/1/all:+tutik/0/1/0/all/0/1</a></p>
<p>This comment may be an over generalization, focusing on my perceived importance trajectories.<br />
I speculate that the importance of trajectories as a “dynamic” dimension or degree of freedom has been overlooked in physics.<br />
The classical 3 spatial dimensions, whether complex, real or “imaginary”, are essentially static on some type of coordinate system, whether commutative or non-commutative, polar or Euclidian.<br />
Trajectory sets may include the sum of all paths with some paths more optimal subsets than others and may be non-commutative even in a commutative coordinate system.<br />
Consider the travel of spacecraft from Earth to Mars and back.<br />
A trajectory from planetary bodies in relative motion with coordinates centered on E0: E0 to M1 on M2 return to E3 where E is Earth, M is Mars and 0,1,2,3 are the relative coordinate positions at times 0, 1, 2, 3.<br />
E0 &#8230;&#8230;. E1 &#8230;&#8230;&#8230;&#8230;&#8230;&#8230;.. E2 &#8230;&#8230;&#8230;&#8230;&#8230;. E3<br />
From to M1 &#8230; when &#8230;&#8230;&#8230;&#8230;&#8230; when<br />
when &#8230;&#8230;&#8230;&#8230;. on M1 to M2 &#8230; from to M3<br />
M0&#8230;&#8230;. M1 &#8230;&#8230;&#8230;&#8230;&#8230;&#8230;. M2 &#8230;&#8230;&#8230;&#8230;&#8230; M3<br />
The simultaneous trajectory from M0 to E1 on E2 back to M3 is not commutative.</p>
<p>On an Earth roadmaps the relative positions of Start to Finish do not change but many trajectory routes are available; not all are optimal.</p>
<p>A reason I discuss this is that I suspect that physics is not using all the mathematical tools available to engineering. These disciplines are historically related.<br />
Just as CP Steinmetz used phasor equation based upon Grassmann Algebra in electrical engineering about 25-30 years before ERJA  Schrodinger used Hamiltonian equations based upon Clifford Algebra in quantum mechanics; today engineers are using dynamic game theory and variants in robotics to correlate electrical calculations with mechanical movements. This is somewhat like naval gunnery using the electronics of fire control radar to operate the mechanical ballistics [trajectory] of gunfire.</p>
<p>The SIAM classic Basar and Olsder, Dynamic Noncooperative Game Theory (Classics in Applied Mathematics), is very complicated mathematics leading to pursuit evasion games.<br />
Paul J Nahin has easy to read engineering based books on extrema and pursuit evasion games:<br />
1- Dr. Euler&#8217;s Fabulous Formula: Cures Many Mathematical Ills,<br />
2 &#8211; When Least Is Best: How Mathematicians Discovered Many Clever Ways to Make Things as Small (or as Large) as Possible,<br />
3 &#8211; Chases and Escapes: The Mathematics of Pursuit and Evasion.</p>
<p>There are more flexible, dioid, idempotent “tropical” variants of this type of mathematics.<br />
I am most familiar with Max Plus Algebra. I have not found a blog on this subject. There is a web homepage. There are many ArXiv articles with Stéphane Gaubert of INRIA among the more prominent authors.<br />
Geert Jan Olsder with others has written Max Plus Algebra as an introductory text.</p>
<p>There are other engineering books that I need to read to better understand applied as opposed to theoretical mathematical solutions.<br />
Much of this material may indirectly be related to John Conway and his work on game theory. I do hope to one day complete  ‘On Quaternions and Octonions’.</p>
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		<title>By: kneemo</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-77995</link>
		<dc:creator>kneemo</dc:creator>
		<pubDate>Thu, 18 Oct 2007 18:26:42 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-77995</guid>
		<description>Alejandro, for more recent work on NCG, KK-theory and branes, see the papers by Richard Szabo (e.g. &lt;a href=&quot;http://arxiv.org/abs/0709.2128&quot; rel=&quot;nofollow&quot;&gt;	arXiv:0709.2128v2 [hep-th]&lt;/a&gt;, &lt;a href=&quot;http://arxiv.org/abs/0708.2648&quot; rel=&quot;nofollow&quot;&gt;	arXiv:0708.2648v1 [hep-th]&lt;/a&gt;).

However, I was more inspired by the K-matrix papers of Asakawa, Sugimoto and Terashima, where a D-brane is realized as a spectral triple and classified by K-homology.  In this construction, a (noncommutative) Dp-brane is constructed by  D-
instantons or D0-branes whose positions are represented by eigen values of the scalar field Hermitian operators (&lt;a href=&quot;http://arxiv.org/abs/hep-th/0505184&quot; rel=&quot;nofollow&quot;&gt;hep-th/0505184&lt;/a&gt;,&lt;a href=&quot;http://arxiv.org/abs/hep-th/0305006&quot; rel=&quot;nofollow&quot;&gt;hep-th/0305006&lt;/a&gt;).

Taking such Dp-brane constructions over to Connes&#039; model, the involutive algebra A=M(3,C)+H+C may actually be producing a noncommutative brane of KO-dimension 6 (mod 8).  We already saw how the C*-algebra M(3,C) itself gives rise to a three-point NCG space, Connes&#039; algebra would be an extension of this case.  From a naive perspective, using the SU(2)  H relation, I&#039;m thinking Connes&#039; is using a six-point space for his finite geometry.  In string theory, the points of this space would likely be identified as D-instantons or D0-branes.

The full geometry of Connes is the product geometry MxF, where M is a 4-dimensional smooth compact Riemannian manifold of KO-dimension 4 and F is the finite space of KO-dimension 6 (mod 8), giving MxF KO-dimension 2 (mod 8).

From pondering Connes&#039; model and its possible relation to Matrix theory, I have also questioned if M could be constructed by D-instantons or D0-branes.  This is tantamount to dispensing with commutative C*-algebras all together and using only their noncommutative counterparts.</description>
		<content:encoded><![CDATA[<p>Alejandro, for more recent work on NCG, KK-theory and branes, see the papers by Richard Szabo (e.g. <a href="http://arxiv.org/abs/0709.2128" rel="nofollow">	arXiv:0709.2128v2 [hep-th]</a>, <a href="http://arxiv.org/abs/0708.2648" rel="nofollow">	arXiv:0708.2648v1 [hep-th]</a>).</p>
<p>However, I was more inspired by the K-matrix papers of Asakawa, Sugimoto and Terashima, where a D-brane is realized as a spectral triple and classified by K-homology.  In this construction, a (noncommutative) Dp-brane is constructed by  D-<br />
instantons or D0-branes whose positions are represented by eigen values of the scalar field Hermitian operators (<a href="http://arxiv.org/abs/hep-th/0505184" rel="nofollow">hep-th/0505184</a>,<a href="http://arxiv.org/abs/hep-th/0305006" rel="nofollow">hep-th/0305006</a>).</p>
<p>Taking such Dp-brane constructions over to Connes&#8217; model, the involutive algebra A=M(3,C)+H+C may actually be producing a noncommutative brane of KO-dimension 6 (mod 8).  We already saw how the C*-algebra M(3,C) itself gives rise to a three-point NCG space, Connes&#8217; algebra would be an extension of this case.  From a naive perspective, using the SU(2)  H relation, I&#8217;m thinking Connes&#8217; is using a six-point space for his finite geometry.  In string theory, the points of this space would likely be identified as D-instantons or D0-branes.</p>
<p>The full geometry of Connes is the product geometry MxF, where M is a 4-dimensional smooth compact Riemannian manifold of KO-dimension 4 and F is the finite space of KO-dimension 6 (mod 8), giving MxF KO-dimension 2 (mod 8).</p>
<p>From pondering Connes&#8217; model and its possible relation to Matrix theory, I have also questioned if M could be constructed by D-instantons or D0-branes.  This is tantamount to dispensing with commutative C*-algebras all together and using only their noncommutative counterparts.</p>
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		<title>By: dorigo</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-77919</link>
		<dc:creator>dorigo</dc:creator>
		<pubDate>Thu, 18 Oct 2007 08:51:05 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-77919</guid>
		<description>Carl, please go ahead. I will be happy to publish it here - I see a lot of interest arising from the latest few guest posts here, so why not continuing with that ? Also, it is much more relaxing to have others write in my place ;-)

Cheers,
T.</description>
		<content:encoded><![CDATA[<p>Carl, please go ahead. I will be happy to publish it here &#8211; I see a lot of interest arising from the latest few guest posts here, so why not continuing with that ? Also, it is much more relaxing to have others write in my place <img src='http://s.wordpress.com/wp-includes/images/smilies/icon_wink.gif' alt=';-)' class='wp-smiley' /> </p>
<p>Cheers,<br />
T.</p>
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		<title>By: Alejandro Rivero</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-77916</link>
		<dc:creator>Alejandro Rivero</dc:creator>
		<pubDate>Thu, 18 Oct 2007 07:58:06 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-77916</guid>
		<description>Thanks for the pointer, I will check recent work from Kerner. I think that now that we know how to build NCG with a KO dimension different from the spectral dimension, one should review the issue of string theory on NCG spaces. It could be a surprise if just  KO dimension 2 mod 8 meets the needs of superstrings!

About using U(6), or SU(6), I doubt. If you check again the section &quot;predictions&quot; on the post, or in sect 3 of the preprint, you will see that it depends very heavily of not linking all the quarks to strings, and in fact the matching of bosons with fermions predicts that you can only link five kind of quarks. But one should want to have this prediction as an outcome, so perhaps leave U(N), or the number of branes, free and then to ask for exact matching again, to see if the answer is N=5. Risking a bit of numerology, it could be easy to get this answer     as one half of the number of dimensions of space time; already    Marcus and Sagnotti (and Weinberg after them) hinted of a link between D/2 and the number of classical Chan-Paton factors.</description>
		<content:encoded><![CDATA[<p>Thanks for the pointer, I will check recent work from Kerner. I think that now that we know how to build NCG with a KO dimension different from the spectral dimension, one should review the issue of string theory on NCG spaces. It could be a surprise if just  KO dimension 2 mod 8 meets the needs of superstrings!</p>
<p>About using U(6), or SU(6), I doubt. If you check again the section &#8220;predictions&#8221; on the post, or in sect 3 of the preprint, you will see that it depends very heavily of not linking all the quarks to strings, and in fact the matching of bosons with fermions predicts that you can only link five kind of quarks. But one should want to have this prediction as an outcome, so perhaps leave U(N), or the number of branes, free and then to ask for exact matching again, to see if the answer is N=5. Risking a bit of numerology, it could be easy to get this answer     as one half of the number of dimensions of space time; already    Marcus and Sagnotti (and Weinberg after them) hinted of a link between D/2 and the number of classical Chan-Paton factors.</p>
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		<title>By: kneemo</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-77892</link>
		<dc:creator>kneemo</dc:creator>
		<pubDate>Thu, 18 Oct 2007 01:12:30 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-77892</guid>
		<description>My apologies, &quot;he&quot; as in Richard Kerner.</description>
		<content:encoded><![CDATA[<p>My apologies, &#8220;he&#8221; as in Richard Kerner.</p>
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		<title>By: kneemo</title>
		<link>http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-77890</link>
		<dc:creator>kneemo</dc:creator>
		<pubDate>Thu, 18 Oct 2007 01:00:09 +0000</pubDate>
		<guid isPermaLink="false">http://dorigo.wordpress.com/2007/10/16/guest-post-alejandro-rivero-sbootstrap/#comment-77890</guid>
		<description>Alejandro, I attended a talk in New York last year where he discussed gauge fields and NCG (see &lt;a href=&quot;http://arxiv.org/abs/hep-th/0408012&quot; rel=&quot;nofollow&quot;&gt;hep-th/0408012&lt;/a&gt;.  He identified the spectral triple for the NxN case and presented a Born-Infeld lagrangian for the corresponding non-abelian gauge theory.  In the D-brane picture such a Born-Infeld lagrangian describes a model of non-linear electrodynamics on a fluctuating p-brane.  Kerner didn&#039;t mention any D-brane intepretations, but this is more likely just a matter of language not physics.

I agree that in Carl&#039;s lepton model, U(3) is more akin to a flavor group.  The three orthonormal primitive idempotents of the spectral decomposition serve as a projective basis for CP^2.  U(3) merely provides a change of basis for CP^2, leaving the corresponding real coefficients (eigenvalues of the Hermitian matrix/square roots of lepton masses) invariant.

I&#039;m not sure how the above generalizes for quarks, but as you stated, one may have to introduce more D-branes to accommodate all the quark flavors.  Perhaps there is a U(6) symmetry in the mass matrix approach to quarks.

Kea, yes, the discrete Fourier transform/circulant connection is promising.</description>
		<content:encoded><![CDATA[<p>Alejandro, I attended a talk in New York last year where he discussed gauge fields and NCG (see <a href="http://arxiv.org/abs/hep-th/0408012" rel="nofollow">hep-th/0408012</a>.  He identified the spectral triple for the NxN case and presented a Born-Infeld lagrangian for the corresponding non-abelian gauge theory.  In the D-brane picture such a Born-Infeld lagrangian describes a model of non-linear electrodynamics on a fluctuating p-brane.  Kerner didn&#8217;t mention any D-brane intepretations, but this is more likely just a matter of language not physics.</p>
<p>I agree that in Carl&#8217;s lepton model, U(3) is more akin to a flavor group.  The three orthonormal primitive idempotents of the spectral decomposition serve as a projective basis for CP^2.  U(3) merely provides a change of basis for CP^2, leaving the corresponding real coefficients (eigenvalues of the Hermitian matrix/square roots of lepton masses) invariant.</p>
<p>I&#8217;m not sure how the above generalizes for quarks, but as you stated, one may have to introduce more D-branes to accommodate all the quark flavors.  Perhaps there is a U(6) symmetry in the mass matrix approach to quarks.</p>
<p>Kea, yes, the discrete Fourier transform/circulant connection is promising.</p>
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