<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>0035-001X</journal-id>
<journal-title><![CDATA[Revista mexicana de física]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. mex. fis.]]></abbrev-journal-title>
<issn>0035-001X</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Mexicana de Física]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0035-001X2007000800011</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Noncommutativity in the Theory of Gravity]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[García-Compeán]]></surname>
<given-names><![CDATA[H]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Obregón]]></surname>
<given-names><![CDATA[O]]></given-names>
</name>
<xref ref-type="aff" rid="A02"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ramírez]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
<xref ref-type="aff" rid="A03"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Centro de Investigación y de Estudios Avanzados del IPN Departamento de Física ]]></institution>
<addr-line><![CDATA[Mexico D.F.]]></addr-line>
<country>México</country>
</aff>
<aff id="A02">
<institution><![CDATA[,Universidad de Guanajuato Instituto de Física ]]></institution>
<addr-line><![CDATA[León Gto]]></addr-line>
<country>México</country>
</aff>
<aff id="A03">
<institution><![CDATA[,Universidad Autónoma de Puebla Facultad de Ciencias Físico Matemáticas ]]></institution>
<addr-line><![CDATA[Puebla ]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>02</month>
<year>2007</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>02</month>
<year>2007</year>
</pub-date>
<volume>53</volume>
<fpage>75</fpage>
<lpage>84</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0035-001X2007000800011&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0035-001X2007000800011&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0035-001X2007000800011&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Noncommutative gravity is a very interesting subject that has not yet been successfully related to string theory. However, it can be motivated by itself by the consideration of a description of the microscopic structure of spacetime, leaving for the future its precise connection to string theory or M-theory. In this paper we review some of the recent attempts to make sense of the noncommutative description of some classical theories of gravity by using the Seiberg-Witten map. In particular we describe noncommutative topological gravity and a gauge invariant proposal generalizing Plebanski-Ashtekar Self-dual gravity.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[La gravedad no conmutativa es un tema muy interesante que, hasta ahora, no ha sido incluido en la teoría de cuerdas. Sin embargo, este tema puede ser motivado mediante la consideración de una descripción microscópica de la estructura del espacio-tiempo, dejando para el futuro su relación precisa con la teoría de cuerdas o la teoría M. En este artículo, revisamos algunos de los intentos recientes para dar sentido a la descripción noconmutativa de algunas teorías clásicas de la gravedad, mediante el uso del mapeo de Seiberg-Witten. En particular, describimos la gravedad topológica no conmutativa y una propuesta no conmutativa e invariante de norma que generaliza la gravedad auto-dual de Plebanski-Ashtekar.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Noncommutative field theory]]></kwd>
<kwd lng="en"><![CDATA[Seiberg-Witten map]]></kwd>
<kwd lng="en"><![CDATA[topological gravity]]></kwd>
<kwd lng="en"><![CDATA[self-dual gravity]]></kwd>
<kwd lng="es"><![CDATA[Teoría de campos no conmutativa]]></kwd>
<kwd lng="es"><![CDATA[mapeo de Seiberg-Witten]]></kwd>
<kwd lng="es"><![CDATA[gravedad topológica]]></kwd>
<kwd lng="es"><![CDATA[gravedad auto-dual]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[ <p align="center"><font face="verdana" size="4"><b>Noncommutativity in the Theory of Gravity</b></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="center"><font face="verdana" size="2"><b>H. Garc&iacute;a&#150;Compe&aacute;n*, O. Obreg&oacute;n** and C. Ram&iacute;rez***</b></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2">* <i>Departamento de F&iacute;sica </i><i>Centro de Investigaci&oacute;n y de Estudios Avanzados del IPN P.O. Box 14&#150;740, 07000, Mexico D.F., M&eacute;xico</i></font></p>     <p align="justify"><font face="verdana" size="2"><i>** Instituto de F&iacute;sica de la Universidad de Guanajuato, P.O. Box E&#150;143, 37150, Le&oacute;n Gto., M&eacute;xico</i></font></p>     <p align="justify"><font face="verdana" size="2"><i>*** </i><i>Facultad de Ciencias F&iacute;sico Matem&aacute;ticas, Universidad Aut&oacute;noma de Puebla, P.O. Box 1364, 72000, Puebla, M&eacute;xico</i></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2">Recibido el 18 de julio de 2005    <br> Aceptado el 14 de marzo de 2005</font></p>     ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><b>Abstract</b></font></p>     <p align="justify"><font face="verdana" size="2">Noncommutative gravity is a very interesting subject that has not yet been successfully related to string theory. However, it can be motivated by itself by the consideration of a description of the microscopic structure of spacetime, leaving for the future its precise connection to string theory or M&#150;theory. In this paper we review some of the recent attempts to make sense of the noncommutative description of some classical theories of gravity by using the Seiberg&#150;Witten map. In particular we describe noncommutative topological gravity and a gauge invariant proposal generalizing Plebanski&#150;Ashtekar Self&#150;dual gravity.</font></p>     <p align="justify"><font face="verdana" size="2"><b>Keywords:</b>  Noncommutative field theory; Seiberg&#150;Witten map; topological gravity; self&#150;dual gravity.</font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><b>Resumen</b></font></p>     <p align="justify"><font face="verdana" size="2">La gravedad no conmutativa es un tema muy interesante que, hasta ahora, no ha sido incluido en la teor&iacute;a de cuerdas. Sin embargo, este tema puede ser motivado mediante la consideraci&oacute;n de una descripci&oacute;n microsc&oacute;pica de la estructura del espacio&#150;tiempo, dejando para el futuro su relaci&oacute;n precisa con la teor&iacute;a de cuerdas o la teor&iacute;a <i>M. </i>En este art&iacute;culo, revisamos algunos de los intentos recientes para dar sentido a la descripci&oacute;n noconmutativa de algunas teor&iacute;as cl&aacute;sicas de la gravedad, mediante el uso del mapeo de Seiberg&#150;Witten. En particular, describimos la gravedad topol&oacute;gica no conmutativa y una propuesta no conmutativa e invariante de norma que generaliza la gravedad auto&#150;dual de Plebanski&#150;Ashtekar.</font></p>     <p align="justify"><font face="verdana" size="2"><b>Descriptores:</b>   Teor&iacute;a de campos no conmutativa; mapeo de Seiberg&#150;Witten; gravedad topol&oacute;gica; gravedad auto&#150;dual.</font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2">PACS: 11.10.Nx; 04.20.Cv; 04.20.Gz; 11.15.Kc</font></p>     ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><a href="/pdf/rmf/v53s2/v53s2a11.pdf">DESCARGAR ART&Iacute;CULO EN FORMATO PDF</a></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><b>Acknowledgments</b></font></p>     <p align="justify"><font face="verdana" size="2">This work was supported in part by CONACyT M&eacute;xico Grant Nos. 37851E, 33951E and 41993E.</font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><b>References</b></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">1. H. Snyder, <i>Phys. 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