<?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>S0035-001X2011000100009</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Relativistic charged particle in a uniform electromagnetic field]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Torres del Castillo]]></surname>
<given-names><![CDATA[G.F.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Sosa Sánchez]]></surname>
<given-names><![CDATA[C]]></given-names>
</name>
<xref ref-type="aff" rid="A02"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Universidad Autónoma de Puebla Instituto de Ciencias Departamento de Física Matemática]]></institution>
<addr-line><![CDATA[Puebla Pue]]></addr-line>
<country>México</country>
</aff>
<aff id="A02">
<institution><![CDATA[,Universidad Autónoma de Puebla Facultad de Ciencias Físico Matemáticas ]]></institution>
<addr-line><![CDATA[Puebla Pue]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>02</month>
<year>2011</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>02</month>
<year>2011</year>
</pub-date>
<volume>57</volume>
<numero>1</numero>
<fpage>53</fpage>
<lpage>59</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0035-001X2011000100009&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0035-001X2011000100009&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0035-001X2011000100009&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[The equations of motion for a relativistic charged particle in a uniform electromagnetic field are solved in a covariant form by calculating the exponential of the matrix corresponding to the electromagnetic field tensor. It is shown that owing to the antisymmetry of the electromagnetic field tensor, the exponential mentioned above can be easily calculated. Some results are then applied to study the algebraic properties of the energy-momentum tensor of the electromagnetic field and the orthogonal transformations in spaces of dimension 4.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Se resuelven las ecuaciones de movimiento de una partícula relativista cargada en un campo electromagnético uniforme en forma covariante, calculando la exponencial de la matriz correspondiente al tensor del campo electromagnético. Se muestra que debido a la antisimetría del tensor del campo electromagnético, dicha exponencial se puede calcular fácilmente. Algunos resultados se aplican para estudiar las propiedades algebraicas del tensor de energía-momento del campo electromagnético y las transformaciones ortogonales en espacios de dimensión 4.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Electromagnetic field]]></kwd>
<kwd lng="en"><![CDATA[matrix exponentials]]></kwd>
<kwd lng="en"><![CDATA[dominant energy condition]]></kwd>
<kwd lng="en"><![CDATA[orthogonal transformations]]></kwd>
<kwd lng="es"><![CDATA[Campo electromagnético]]></kwd>
<kwd lng="es"><![CDATA[exponenciales de matrices]]></kwd>
<kwd lng="es"><![CDATA[condición de energía dominante]]></kwd>
<kwd lng="es"><![CDATA[transformaciones ortogonales]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[  	    <p align="justify"><font face="verdana" size="4">Investigaci&oacute;n</font></p> 	    <p align="center"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="center"><font face="verdana" size="4"><b>Relativistic charged particle in a uniform electromagnetic field</b></font></p> 	    <p align="center"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="center"><font face="verdana" size="2"><b>G.F. Torres del Castillo&ordf;, C. Sosa S&aacute;nchez<sup>b</sup></b></font></p> 	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="justify"><font face="verdana" size="2"><i>&ordf; Departamento de F&iacute;sica Matem&aacute;tica, Instituto de Ciencias, Universidad Aut&oacute;noma de Puebla, </i><i>Puebla, Pue., 72570, M&eacute;xico.</i></font></p> 	    <p align="justify"><font face="verdana" size="2"><i><sup>b</sup> Facultad de Ciencias F&iacute;sico Matem&aacute;ticas, Universidad Aut&oacute;noma de Puebla, Apartado postal 1152 Puebla, Pue.,72001, M&eacute;xico.</i></font></p> 	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p> 	    ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">Recibido el 14 de mayo de 2010    <br>     Aceptado el 16 de noviembre de 2010</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">The equations of motion for a relativistic charged particle in a uniform electromagnetic field are solved in a covariant form by calculating the exponential of the matrix corresponding to the electromagnetic field tensor. It is shown that owing to the antisymmetry of the electromagnetic field tensor, the exponential mentioned above can be easily calculated. Some results are then applied to study the algebraic properties of the energy&#150;momentum tensor of the electromagnetic field and the orthogonal transformations in spaces of dimension 4.</font></p> 	    <p align="justify"><font face="verdana" size="2"><b>Keywords:</b> Electromagnetic field; matrix exponentials; dominant energy condition; orthogonal transformations.</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">Se resuelven las ecuaciones de movimiento de una part&iacute;cula relativista cargada en un campo electromagn&eacute;tico uniforme en forma covariante, calculando la exponencial de la matriz correspondiente al tensor del campo electromagn&eacute;tico. Se muestra que debido a la antisimetr&iacute;a del tensor del campo electromagn&eacute;tico, dicha exponencial se puede calcular f&aacute;cilmente. Algunos resultados se aplican para estudiar las propiedades algebraicas del tensor de energ&iacute;a&#150;momento del campo electromagn&eacute;tico y las transformaciones ortogonales en espacios de dimensi&oacute;n 4.</font></p> 	    <p align="justify"><font face="verdana" size="2"><b>Descriptores:</b> Campo electromagn&eacute;tico; exponenciales de matrices; condici&oacute;n de energ&iacute;a dominante; transformaciones ortogonales.</font></p> 	    ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="justify"><font face="verdana" size="2">PACS: 03.30.+p; 03.50.De; 02.20.Qs</font></p> 	    <p align="justify"><font face="verdana" size="2">&nbsp;</font></p> 	    <p align="justify"><font size="2" face="verdana"><a href="/pdf/rmf/v57n1//v57n1a9.pdf" target="_blank">DESCARGAR ART&Iacute;CULO EN FORMATO PDF</a></font></p> 	    <p align="justify"><font face="verdana" size="2">&nbsp;</font><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. A.H. Taub, <i>Phys. Rev.</i> <b>73</b> (1948) 786.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8419736&pid=S0035-001X201100010000900001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p> 	    <!-- ref --><p align="justify"><font face="verdana" size="2">2. A.T. Hyman, <i>Am. J. Phys.</i> <b>65</b> (1997) 195.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8419738&pid=S0035-001X201100010000900002&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --></font></p> 	    ]]></body>
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