<?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>1409-2433</journal-id>
<journal-title><![CDATA[Revista de Matemática Teoría y Aplicaciones]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. Mat]]></abbrev-journal-title>
<issn>1409-2433</issn>
<publisher>
<publisher-name><![CDATA[Centro de Investigaciones en Matemática Pura y Aplicada (CIMPA) y Escuela de Matemática, San José, Costa Rica.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1409-24332017000100045</article-id>
<article-id pub-id-type="doi">10.15517/rmta.v24i1.27749</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[El fenómeno del espín semientero, cuaternios, y matrices de Pauli]]></article-title>
<article-title xml:lang="en"><![CDATA[The phenomenon of half-integer spin, quaternions, and Pauli matrices]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[González-Díaz]]></surname>
<given-names><![CDATA[Fernando R.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[García-Salcedo]]></surname>
<given-names><![CDATA[Ricardo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Escuela Agrícola Panamericana  ]]></institution>
<addr-line><![CDATA[ ]]></addr-line>
<country>HN</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Instituto Politécnico Nacional  ]]></institution>
<addr-line><![CDATA[ México D.F.]]></addr-line>
<country>MX</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2017</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2017</year>
</pub-date>
<volume>24</volume>
<numero>1</numero>
<fpage>45</fpage>
<lpage>60</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_arttext&amp;pid=S1409-24332017000100045&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_abstract&amp;pid=S1409-24332017000100045&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.sa.cr/scielo.php?script=sci_pdf&amp;pid=S1409-24332017000100045&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[ResumenEn este trabajo se reproduce el fenómeno del espín semientero de la ejemplificación que hizo Paul A. M. Dirac con un par de tijeras, una cuerda elástica y una silla. Se describen tres ejemplos más en el que aparece el mismo fenómeno y se relaciona la estructura algebraica de los cuaternios con uno de los ejemplos. Se describen los resultados básicos de las estructuras algebraicas de los cuaternios H, y se establece una relación intrínseca con el fenómeno espín semientero y las matrices de Pauli.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[AbstractIn this paper the phenomenon of half-integer spin exemplification Paul AM Dirac made with a pair of scissors, an elastic cord and chair play. Four examples in which the same phenomenon appears and the algebraic structure of quaternions is related to one of the examples are described. [20] Mathematical proof of the phenomenon using known topological and algebraic results are explained. The basic results of algebraic structures are described quaternions H, and an intrinsic relationship with the phenomenon half-integer spin and the Pauli matrices is established.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Espín semientero]]></kwd>
<kwd lng="es"><![CDATA[Cuaternios]]></kwd>
<kwd lng="es"><![CDATA[matrices de Pauli]]></kwd>
<kwd lng="es"><![CDATA[grupo fundamental]]></kwd>
<kwd lng="en"><![CDATA[half-integer spin]]></kwd>
<kwd lng="en"><![CDATA[quaternions]]></kwd>
<kwd lng="en"><![CDATA[Pauli matrices]]></kwd>
<kwd lng="en"><![CDATA[fundamental group]]></kwd>
</kwd-group>
</article-meta>
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