<?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>0034-7426</journal-id>
<journal-title><![CDATA[Revista Colombiana de Matemáticas]]></journal-title>
<abbrev-journal-title><![CDATA[Rev.colomb.mat.]]></abbrev-journal-title>
<issn>0034-7426</issn>
<publisher>
<publisher-name><![CDATA[Universidad Nacional de Colombia y Sociedad Colombiana de Matemáticas]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0034-74262005000200004</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Corchete y curvatura]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Di Scala]]></surname>
<given-names><![CDATA[Antonio J.]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Politecnico di Torino Dipartimento di Matematica ]]></institution>
<addr-line><![CDATA[Torino ]]></addr-line>
<country>Italy</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2005</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2005</year>
</pub-date>
<volume>39</volume>
<numero>2</numero>
<fpage>113</fpage>
<lpage>131</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0034-74262005000200004&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0034-74262005000200004&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0034-74262005000200004&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[The first part of this article presents the definition of Lie Bracket related to commuting flows of vector fields. In the second part, basic definitions and of connections and curvature are given in order to emphasize the link between Lie Brackets and curvature. Finally, by using locally-defined connections, we give a short and original proof of a classical theorem of Beltrami. The article is addressed to a non specialist in local differential geometry.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[La primera parte del artículo presenta al corchete de Lie asociado al problema de la comutatividad de dos flujos. En la segunda parte se introducen las definiciones básicas de conexión y curvatura en fibrados vectoriales, subrayando la relación corchete-curvatura. Finalmente, usando conexiones afines localmente definidas, se da una demostración original y sencilla de un teorema de Eugenio Beltrami. Este artículo apunta a un lector no especialista (e.g. un estudiante de doctorado en matemática o física, etc) en geometría diferencial local.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[Lie Bracket]]></kwd>
<kwd lng="en"><![CDATA[curvature tensor]]></kwd>
<kwd lng="en"><![CDATA[a±ne connection]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[  <font size="2" face=verdana>      <p> <font size="4">       <center>   <b>Corchete y curvatura</b>   </center>  </font></p>     <p>&nbsp;</p>     <p><b>Antonio J. Di Scala</b></p>     <p>Dipartimento di Matematica. Politecnico di Torino. Corso Duca degli Abruzzi    24, 10129 Torino - Italy</p>     <p>e-mail: <a href="mailto:antonio.discala@polito.it">antonio.discala@polito.it</a></p> <hr>     <p><b>Abstract.</b> The first part of this article presents the definition of    Lie Bracket related to commuting flows of vector fields. In the second part,    basic definitions and of connections and curvature are given in order to emphasize    the link between Lie Brackets and curvature. Finally, by using locally-defined    connections, we give a short and original proof of a classical theorem of Beltrami.    The article is addressed to a non specialist in local differential geometry.</p>     <p><b><i>Keywords and phrases.</i></b> Lie Bracket, curvature tensor, a&plusmn;ne    connection.</p>     <p><i>2000 Mathematics Subject Classification.</i> Primary: 53B20. Secondary:    53B21.</p> <hr size="1">     ]]></body>
<body><![CDATA[<p><b>Resumen.</b> La primera parte del art&iacute;culo presenta al corchete de    Lie asociado al problema de la comutatividad de dos flujos. En la segunda parte    se introducen las definiciones b&aacute;sicas de conexi&oacute;n y curvatura    en fibrados vectoriales, subrayando la relaci&oacute;n corchete-curvatura. Finalmente,    usando conexiones afines localmente definidas, se da una demostraci&oacute;n    original y sencilla de un teorema de Eugenio Beltrami. Este art&iacute;culo    apunta a un lector no especialista (e.g. un estudiante de doctorado en matem&aacute;tica    o f&iacute;sica, etc) en geometr&iacute;a diferencial local.</p> <hr>     <p>FULL TEXT IN <a href="pdf/rcm/v39n2/v39n2a04.pdf">PDF</a></p> <hr>     <p>    <center><b>Referencias</b></center></p>     <!-- ref --><p> [BCO] J. Berndt, S. Console and C. 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