<?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>1870-3542</journal-id>
<journal-title><![CDATA[Revista mexicana de física E]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. mex. fís. E]]></abbrev-journal-title>
<issn>1870-3542</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Mexicana de Física]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1870-35422018000200162</article-id>
<title-group>
<article-title xml:lang="en"><![CDATA[Clifford&#8217;s attempt to test his gravitation hypothesis]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Galindo]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Cervantes-Cota]]></surname>
<given-names><![CDATA[Jorge L.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Instituto Nacional de Investigaciones Nucleares  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>Mexico</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>12</month>
<year>2018</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>12</month>
<year>2018</year>
</pub-date>
<volume>64</volume>
<numero>2</numero>
<fpage>162</fpage>
<lpage>168</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1870-35422018000200162&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1870-35422018000200162&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1870-35422018000200162&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract Almost half a century before Einstein expounded his general theory of relativity, the English mathematician William Kingdon Clifford argued that space might not be Euclidean and proposed that matter is nothing but a small distortion in that spatial curvature. He further proposed that matter in motion is not more than the simple variation in space of this distortion. In this work, we conjecture that Clifford went further than his aforementioned proposals, as he tried to show that matter effectively curves space. For this purpose he made an unsuccessful observation on the change of the plane of polarization of the skylight during the solar eclipse of December 22, 1870 in Sicily.]]></p></abstract>
<abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen Casi medio siglo antes de que Einstein expusiera su teoría general de la relatividad, el matemático inglés William Kingdon Clifford argumentó que el espacio podría no ser euclidiano y propuso que la materia no es más que una pequeña distorsión en esa curvatura espacial. Propuso además que la materia en movimiento no es más que la simple variación en el espacio de esta distorsión. En este trabajo, conjeturamos que Clifford fue más allá de dichas propuestas, pues trató de demostrar que efectivamente la materia curva el espacio. Para ello hizo una observación infructuosa sobre el cambio del plano de polarización de la luz solar durante el eclipse solar del 22 de diciembre de 1870 en Sicilia.]]></p></abstract>
<kwd-group>
<kwd lng="en"><![CDATA[W.K. Clifford]]></kwd>
<kwd lng="en"><![CDATA[test of gravitational theories]]></kwd>
<kwd lng="en"><![CDATA[history of gravitation]]></kwd>
<kwd lng="en"><![CDATA[history of general relativity]]></kwd>
<kwd lng="es"><![CDATA[W.K. Clifford]]></kwd>
<kwd lng="es"><![CDATA[prueba de teorías gravitacionales]]></kwd>
<kwd lng="es"><![CDATA[historia de la gravitación]]></kwd>
<kwd lng="es"><![CDATA[historia de la relatividad general]]></kwd>
</kwd-group>
</article-meta>
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