<?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>S0035-001X2007001000013</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Singularidades en modelos Bianchi con electrodinámica no lineal]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[García-Salcedo]]></surname>
<given-names><![CDATA[R]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,CINVESTAV  ]]></institution>
<addr-line><![CDATA[Monterrey N.L.]]></addr-line>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>08</month>
<year>2007</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>08</month>
<year>2007</year>
</pub-date>
<volume>53</volume>
<fpage>61</fpage>
<lpage>65</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0035-001X2007001000013&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0035-001X2007001000013&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0035-001X2007001000013&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[En esta contribución se presenta una breve recopilación de soluciones de las ecuaciones de Einstein acopladas con electrodinámica no lineal. Estas soluciones corresponden a espacios tipo Petrov D, homogéneas y anisotrópicas, la cual tiene como algunos casos particulares a varios espacios confermes a Bianchi, entre ellos G3I, G3II, G3III, G3VIII, G3IX y Kantowski- Sachs. La materia que acoplamos a dicha métrica es la electrodinámica no lineal de Born-Infeld, [17]. Posteriormente se realiza un análisis de geodésicas el cual nos indica que G3VIII es geodesicamente completo, pero que para G3II y G3IX el análisis no es concluyente. Mientras que para G3I, G3III y Kantowski-Sachs, se muestra que son geodésicamente incompletos.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[In this contribution we shall to present a brief compilation of the Einstein field equation solutions coupled with with nonlinear electrodynamics. The metric used correspond to homogenous and anisotropic spaces Petrov type D, which has some particular cases to several conformal to Bianchi spaces, among them G3I, G3II, G3III, G3VIII, G3IX and Kantowski-Sachs. We coupled Born-Infeld nonlinear electrodynamics with this metric [17]. Finally, an analysis of geodesic is made which indicates us that G3 VIII is geodesically complete, but in the analysis for GII and GIX is not conclusive. Whereas for G3I, G3III and the Kantowski-Sachs, it shows that are geodesically incomplete.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Petrov D]]></kwd>
<kwd lng="es"><![CDATA[Electrodinámica de Born-Infeld]]></kwd>
<kwd lng="es"><![CDATA[Análisis de geodésicas]]></kwd>
<kwd lng="en"><![CDATA[Petrov type D]]></kwd>
<kwd lng="en"><![CDATA[Born-Infeld electrodynamics]]></kwd>
<kwd lng="en"><![CDATA[geodesic analysis]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[ <p align="center"><font face="verdana" size="4"><b>Singularidades en modelos Bianchi con electrodin&aacute;mica no lineal</b></font></p>     <p align="center"><font face="verdana" size="2">&nbsp;</font></p>     <p align="center"><font face="verdana" size="2"><b>R. Garc&iacute;a&#150;Salcedo</b></font></p>     <p align="center"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><i>CINVESTAV&#150;Monterrey, </i><i>Av. Cerro de las Mitras 2565, Col. Obispado, Monterrey, 64060 N.L., e&#150;mail: <a href="mailto:rsalcedo@fis.cinvestav.mx" target="_blank">rsalcedo@fis.cinvestav.mx</a></i></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2">Recibido el 1 de mayo de 2006    <br> Aceptado el 1 de noviembre de 2006</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>     ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">En esta contribuci&oacute;n se presenta una breve recopilaci&oacute;n de soluciones de las ecuaciones de Einstein acopladas con electrodin&aacute;mica no lineal. Estas soluciones corresponden a espacios tipo Petrov D, homog&eacute;neas y anisotr&oacute;picas, la cual tiene como algunos casos particulares a varios espacios confermes a Bianchi, entre ellos G3I, G3II, G3III, G3VIII, G3IX y Kantowski&#151; Sachs. La materia que acoplamos a dicha m&eacute;trica es la electrodin&aacute;mica no lineal de Born&#150;Infeld, &#91;17&#93;. Posteriormente se realiza un an&aacute;lisis de geod&eacute;sicas el cual nos indica que G3VIII es geodesicamente completo, pero que para G3II y G3IX el an&aacute;lisis no es concluyente. Mientras que para G3I, G3III y Kantowski&#151;Sachs, se muestra que son geod&eacute;sicamente incompletos.</font></p>     <p align="justify"><font face="verdana" size="2"><b>Descriptores: </b>Petrov D; Electrodin&aacute;mica de Born&#150;Infeld; An&aacute;lisis de geod&eacute;sicas.</font></p>     <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">In this contribution we shall to present a brief compilation of the Einstein field equation solutions coupled with with nonlinear electrodynamics. The metric used correspond to homogenous and anisotropic spaces Petrov type D, which has some particular cases to several conformal to Bianchi spaces, among them G3I, G3II, G3III, G3VIII, G3IX and Kantowski&#150;Sachs. We coupled Born&#150;Infeld nonlinear electrodynamics with this metric &#91;17&#93;. Finally, an analysis of geodesic is made which indicates us that G3 VIII is geodesically complete, but in the analysis for GII and GIX is not conclusive. Whereas for G3I, G3III and the Kantowski&#150;Sachs, it shows that are geodesically incomplete.</font></p>     <p align="justify"><font face="verdana" size="2"><b>Keywords: </b>Petrov type D; Born&#150;Infeld electrodynamics; geodesic analysis.</font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2">PACS:  98.80.Hw; 11.10.Lm; 04.20.Dw</font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><a href="/pdf/rmf/v53s4/v53s4a13.pdf">DESCARGAR ART&Iacute;CULO EN FORMATO PDF</a></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>Agradecimientos</b></font></p>     <p align="justify"><font face="verdana" size="2">Se agradece a Nora Bret&oacute;n por sus apreciables y fruct&iacute;feras conversaciones, as&iacute; como sus aportaciones para la escritura de este trabajo. De la misma forma a Claudia Moreno y Aar&oacute;n V. B. Arellano por la revisi&oacute;n de este manuscrito. Finalmente a Lorena Ram&iacute;rez, por su constante apoyo y cari&ntilde;o.</font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><b>Referencias</b></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">1. S. Hawking and G. 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