<?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>S0034-74262009000200001</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Operadores de Toeplitz en la 2-esfera]]></article-title>
<article-title xml:lang="en"><![CDATA[Toeplitz's operators on the 2-sphere]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[PRIETO SANABRIA]]></surname>
<given-names><![CDATA[ERNESTO]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Universidad Tecnológica de Pereira  ]]></institution>
<addr-line><![CDATA[Pereira ]]></addr-line>
<country>Colombia</country>
</aff>
<pub-date pub-type="pub">
<day>15</day>
<month>12</month>
<year>2009</year>
</pub-date>
<pub-date pub-type="epub">
<day>15</day>
<month>12</month>
<year>2009</year>
</pub-date>
<volume>43</volume>
<numero>2</numero>
<fpage>87</fpage>
<lpage>99</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_arttext&amp;pid=S0034-74262009000200001&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_abstract&amp;pid=S0034-74262009000200001&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.co/scielo.php?script=sci_pdf&amp;pid=S0034-74262009000200001&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[En este artículo se demuestra que el operador de Toeplitz Ta con símbolo radial actuando en los espacios de Bergman con peso Ah²(C) es unitariamente equivalente a un operador de multiplicación y se obtienen algunos corolarios de este resultado.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[In the article we study the Toeplitz operators defined on the 2-sphere. We show that the Toeplitz operators Ta with radial symbol, acting on the Bergman space A²h(C), is unitary equivalent to a multiplication operator.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Espacio de Bergman]]></kwd>
<kwd lng="es"><![CDATA[proyección de Bergman]]></kwd>
<kwd lng="es"><![CDATA[operador de Toeplitz]]></kwd>
<kwd lng="en"><![CDATA[Bergman space]]></kwd>
<kwd lng="en"><![CDATA[Bergman projection]]></kwd>
<kwd lng="en"><![CDATA[Toeplitz operator]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[ 
<font size="2" face="verdana">

    <p>
<b>
<font size="4">
    <center>
Operadores de Toeplitz en la 2-esfera
</center>
</font>
</b>
</p>

    <p>
<b>
<font size="3">
    <center>
Toeplitz's operators on the 2-sphere
</center>
</font>
</b>
</p>

    <p>
    <center>
ERNESTO PRIETO SANABRIA<sup>1</sup>
</center>
</p>

    <p>
<sup>1</sup>Universidad Tecnol&oacute;gica de Pereira, Pereira, Colombia. Email: <a href="mailto:ernespri@utp.edu.co">ernespri@utp.edu.co</a>
    <br>
</p>

<hr size="1">

    <p>
<b>
    ]]></body>
<body><![CDATA[<center>
Resumen
</center>
</b>
</p>

    <p>
En este art&iacute;culo se demuestra que el operador de Toeplitz <i>T<sub>a</sub></i> con s&iacute;mbolo radial actuando en los espacios de Bergman con peso <i>A<sub>h</sub><sup>2</sup>(<b>C</b>)</i> es unitariamente equivalente a un operador de multiplicaci&oacute;n y se obtienen algunos corolarios de este resultado.
</p>

    <p>
<b>
Palabras clave:
</b>
Espacio de Bergman,
proyecci&oacute;n de Bergman,
operador de Toeplitz.
</p>

<hr size="1">

<i>2000 Mathematics Subject Classification: 47B35, 30A31.</i>

<hr size="1">

    <p>
<b>
    <center>
Abstract
</center>
</b>
</p>

    <p>
In the article we study the Toeplitz operators defined on the 2-sphere. We show that the Toeplitz operators <i>T<sub>a</sub></i> with radial symbol, acting on the Bergman space <i>A<sup>2</sup><sub>h</sub>(<b>C</b>)</i>, is unitary equivalent to a multiplication operator.
</p>

    <p>
<b>
Key words:
</b>
Bergman space,
Bergman projection,
Toeplitz operator.
</p>

<hr size="1">

    <p>
Texto completo disponible en <a href="pdf/rcm/v43n2/v43n2a01.pdf">PDF</a>
</p>

<hr size="1">

    <p>
<b>
<font size="3">
Referencias
</font>
</b>
</p>


    <!-- ref --><p>
[1] F. A. Berezin, <i>M&eacute;todo de la segunda cuantizaci&oacute;n (En Ruso)</i>, Nauka, Mosc&uacute;, 1965.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000022&pid=S0034-7426200900020000100001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p>
[2] A. I. Kiseliov, M. Krasnov, and G. Makarenko, <i>Problemas de ecuaciones diferenciales ordinarias</i>, Instituto Polit&eacute;cnico Nacional, M&eacute;xico D. F., 1990.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000023&pid=S0034-7426200900020000100002&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p>
[3] E. Prieto, Operadores de Toeplitz en la 2-esfera, Master's thesis, CINVESTAV-IPN, M&eacute;xico D. F., 2004.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000024&pid=S0034-7426200900020000100003&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p>
[4] N. L. Vasilevski, `Toeplitz operators on the Bergman spaces: inside-the-domain effects´, <i>Contemporary Mathematics</i> <i>289</i>,  (2001), 79-146.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000025&pid=S0034-7426200900020000100004&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p>
[5] N. L. Vasilevski, S. Grudsky, and A. Karapetyants, Toeplitz operators on the unit ball in <i><b>C</b><sup>n</sup></i>, with radial symbols, Reporte interno 292, Departamento de Matematicas, CINVESTAV del I.P.N., M&eacute;xico D. F., 2001.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000026&pid=S0034-7426200900020000100005&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p>
[6] N. L. Vasilevski, S. Grudsky, and A. Karapetyants, Dynamics of properties of toeplitz operators with radial symbols, Reporte interno 317, Departamento de Matematicas, CINVESTAV del I.P.N., M&eacute;xico D. F., 2002.
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=000027&pid=S0034-7426200900020000100006&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><center>
<b>(Recibido en agosto de 2006. Aceptado en julio de 2009)</b>
</center>
<hr size="1">

    <p>
Este art&iacute;culo se puede citar en <i>LaTeX</i> utilizando la siguiente referencia bibliogr&aacute;fica de <i>BibTeX</i>:
</p>
<code><font size="2">@ARTICLE{RCMv43n2a01,    <br>
 &nbsp;&nbsp;&nbsp; AUTHOR &nbsp;= {Prieto Sanabria, Ernesto},    <br>
 &nbsp;&nbsp;&nbsp; TITLE &nbsp; = {{Operadores de Toeplitz en la 2-esfera}},    <br>
 &nbsp;&nbsp;&nbsp; JOURNAL = {Revista Colombiana de Matem&aacute;ticas},    ]]></body>
<body><![CDATA[<br>
&nbsp;&nbsp;&nbsp; YEAR &nbsp;&nbsp; = {2009},    <br>
&nbsp;&nbsp;&nbsp; volume &nbsp;= {43},    <br>
&nbsp;&nbsp;&nbsp; number &nbsp;= {2},    <br>
&nbsp;&nbsp;&nbsp; pages &nbsp; = {87-99}    <br>
}</font></code>

<hr size="1">
</font>
     ]]></body><back>
<ref-list>
<ref id="B1">
<label>1</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Berezin]]></surname>
<given-names><![CDATA[F. A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Método de la segunda cuantización (En Ruso)]]></source>
<year>1965</year>
<publisher-name><![CDATA[Nauka]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B2">
<label>2</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kiseliov]]></surname>
<given-names><![CDATA[A. I.]]></given-names>
</name>
<name>
<surname><![CDATA[Krasnov]]></surname>
<given-names><![CDATA[M.]]></given-names>
</name>
<name>
<surname><![CDATA[Makarenko]]></surname>
<given-names><![CDATA[G.]]></given-names>
</name>
</person-group>
<source><![CDATA[Problemas de ecuaciones diferenciales ordinarias]]></source>
<year>1990</year>
<publisher-name><![CDATA[Instituto Politécnico Nacional]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B3">
<label>3</label><nlm-citation citation-type="">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Prieto]]></surname>
<given-names><![CDATA[E.]]></given-names>
</name>
</person-group>
<source><![CDATA[Operadores de Toeplitz en la 2-esfera]]></source>
<year></year>
</nlm-citation>
</ref>
<ref id="B4">
<label>4</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Vasilevski]]></surname>
<given-names><![CDATA[N. L.]]></given-names>
</name>
</person-group>
<article-title xml:lang="en"><![CDATA[`Toeplitz operators on the Bergman spaces: inside-the-domain effects´]]></article-title>
<source><![CDATA[Contemporary Mathematics]]></source>
<year>2001</year>
<volume>289</volume>
<page-range>79-146</page-range></nlm-citation>
</ref>
<ref id="B5">
<label>5</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Vasilevski]]></surname>
<given-names><![CDATA[N. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Grudsky]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
<name>
<surname><![CDATA[Karapetyants]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Toeplitz operators on the unit ball in Cn, with radial symbols]]></source>
<year>2001</year>
<publisher-name><![CDATA[Departamento de Matematicas, CINVESTAV del I.P.N.]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B6">
<label>6</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Vasilevski]]></surname>
<given-names><![CDATA[N. L.]]></given-names>
</name>
<name>
<surname><![CDATA[Grudsky]]></surname>
<given-names><![CDATA[S.]]></given-names>
</name>
<name>
<surname><![CDATA[Karapetyants]]></surname>
<given-names><![CDATA[A.]]></given-names>
</name>
</person-group>
<source><![CDATA[Dynamics of properties of toeplitz operators with radial symbols]]></source>
<year>2002</year>
<publisher-name><![CDATA[Departamento de Matematicas, CINVESTAV del I.P.N.]]></publisher-name>
</nlm-citation>
</ref>
</ref-list>
</back>
</article>
