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Am. Math. Soc.</a> <a href="/?q=in%3A120819" title="Articles in this Issue">134, No. 2, 411-418 (2006)</a>. </div> <div class="abstract">An ordered \(L\)-space \((X,\rightarrow ,\leq )\) consists of a nonempty set \(X\), a convergence structure \(\rightarrow\) on the set of the sequences in \(X\) and an ordering relation \(\leq\) on \(X\), the two being connected by some conditions of compatibility. In this paper, the authors establish several sufficient conditions in order that an operator \(f:X\rightarrow X\) defined on an ordered \(L\)-space to be a Picard operator (that is, to have a unique fixed point \(x^*\) and, for each \(x\in X\), the sequence \((f^n(x))\) of successive approximations to converge to \(x^*\)). Finally, some applications to matrix equations are considered.<div class="reviewer"> Reviewer: <a href="/authors/?q=rv%3A10169">Mircea Balaj (Oradea)</a></div> <div class="clearfix"></div></div> <div class="clear"></div> <br> <div class="citations"><div class="clear"><a href="/?q=ci%3A2227181">Cited in <strong>5</strong> Reviews</a></div><div class="clear"><a href="/?q=rf%3A2227181">Cited in <strong>119</strong> Documents</a></div></div> <div class="classification"> <h3>MSC:</h3> <table><tr> <td> <a class="mono" href="/classification/?q=cc%3A54H25" title="MSC2020">54H25</a> </td> <td class="space"> Fixed-point and coincidence theorems (topological aspects) </td> </tr><tr> <td> <a class="mono" href="/classification/?q=cc%3A54E40" title="MSC2020">54E40</a> </td> <td class="space"> Special maps on metric spaces </td> </tr><tr> <td> <a class="mono" href="/classification/?q=cc%3A54F05" title="MSC2020">54F05</a> </td> <td class="space"> Linearly ordered topological spaces, generalized ordered spaces, and partially ordered spaces </td> </tr><tr> <td> <a class="mono" href="/classification/?q=cc%3A54E70" title="MSC2020">54E70</a> </td> <td class="space"> Probabilistic metric spaces </td> </tr><tr> <td> <a class="mono" href="/classification/?q=cc%3A15A24" title="MSC2020">15A24</a> </td> <td class="space"> Matrix equations and identities </td> </tr></table> </div><div class="keywords"> <h3>Keywords:</h3><a href="/?q=ut%3AL-space">L-space</a>; <a href="/?q=ut%3Aordered+L-space">ordered L-space</a>; <a href="/?q=ut%3Afixed+point">fixed point</a>; <a href="/?q=ut%3APicard+operator">Picard operator</a>; <a href="/?q=ut%3Aweakly+Picard+operator">weakly Picard operator</a>; <a href="/?q=ut%3Amatrix+equation">matrix equation</a></div><div class="keywords"> <h3>Citations:</h3><a href="/1060.47056">Zbl 1060.47056</a></div> <!-- Modal used to show zbmath metadata in different output formats--> <div class="modal fade" id="metadataModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel"> <div class="modal-dialog" role="document"> <div class="modal-content"> <div class="modal-header"> <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">×</span></button> <h4 class="modal-title" id="myModalLabel">Cite</h4> </div> <div class="modal-body"> <div class="form-group"> <label for="select-output" class="control-label">Format</label> <select id="select-output" class="form-control" aria-label="Select Metadata format"></select> </div> <div class="form-group"> <label for="metadataText" class="control-label">Result</label> <textarea class="form-control" id="metadataText" rows="10" style="min-width: 100%;max-width: 100%"></textarea> </div> <div id="metadata-alert" class="alert alert-danger" role="alert" style="display: none;"> <!-- alert for connection errors etc --> </div> </div> <div class="modal-footer"> <button type="button" class="btn btn-primary" onclick="copyMetadata()">Copy to clipboard</button> <button type="button" class="btn btn-default" data-dismiss="modal">Close</button> </div> </div> </div> </div> <div class="functions clearfix"> <div class="function"> <!-- Button trigger metadata modal --> <a type="button" class="btn btn-default btn-xs pdf" data-toggle="modal" data-target="#metadataModal" data-itemtype="Zbl" data-itemname="Zbl 1086.47026" data-ciurl="/ci/02227181" data-biburl="/bibtex/02227181.bib" data-amsurl="/amsrefs/02227181.bib" data-xmlurl="/xml/02227181.xml" > Cite </a> <a class="btn btn-default btn-xs pdf" data-container="body" type="button" href="/pdf/02227181.pdf" title="Zbl 1086.47026 as PDF">Review PDF</a> </div> <div class="fulltexts"> <span class="fulltext">Full Text:</span> <a class="btn btn-default btn-xs" type="button" href="https://doi.org/10.1090/S0002-9939-05-07982-7" aria-label="DOI for “Fixed point theorems in ordered \(L\)-spaces”" title="10.1090/S0002-9939-05-07982-7">DOI</a> </div> <div class="sfx" style="float: right;"> </div> </div> <div class="references"> <h3>References:</h3> <table><tr> <td>[1]</td> <td class="space">T. A. Burton, Integral equations, implicit functions, and fixed points, Proc. Amer. Math. Soc. 124 (1996), no. 8, 2383 – 2390. · <a href="/0873.45003" class="nowrap">Zbl 0873.45003</a></td> </tr><tr> <td>[2]</td> <td class="space">E. De Pascale, G. Marino, and P. Pietramala, The use of the \?-metric spaces in the search for fixed points, Matematiche (Catania) 48 (1993), no. 2, 367 – 376 (1994). · <a href="/0833.47049" class="nowrap">Zbl 0833.47049</a></td> </tr><tr> <td>[3]</td> <td class="space">Maurice Fréchet, Les espaces abstraits, Les Grands Classiques Gauthier-Villars. [Gauthier-Villars Great Classics], Éditions Jacques Gabay, Sceaux, 1989 (French). Reprint of the 1928 original. · <a href="/0033.28901" class="nowrap">Zbl 0033.28901</a></td> </tr><tr> <td>[4]</td> <td class="space">O. Hadžić, E. Pap, and V. Radu, Generalized contraction mapping principles in probabilistic metric spaces, Acta Math. Hungar. 101 (2003), no. 1-2, 131 – 148. · <a href="/1050.47052" class="nowrap">Zbl 1050.47052</a> · <a href="https://doi.org/10.1023/B:AMHU.0000003897.39440.d8" class="nowrap">doi:10.1023/B:AMHU.0000003897.39440.d8</a></td> </tr><tr> <td>[5]</td> <td class="space">Olga Hadžić and Endre Pap, Fixed point theory in probabilistic metric spaces, Mathematics and its Applications, vol. 536, Kluwer Academic Publishers, Dordrecht, 2001. · <a href="/0994.47077" class="nowrap">Zbl 0994.47077</a></td> </tr><tr> <td>[6]</td> <td class="space">William A. Kirk and Brailey Sims , Handbook of metric fixed point theory, Kluwer Academic Publishers, Dordrecht, 2001. · <a href="/0970.54001" class="nowrap">Zbl 0970.54001</a></td> </tr><tr> <td>[7]</td> <td class="space">James Merryfield and James D. Stein Jr., A generalization of the Banach contraction principle, J. Math. Anal. Appl. 273 (2002), no. 1, 112 – 120. · <a href="/1029.54046" class="nowrap">Zbl 1029.54046</a> · <a href="https://doi.org/10.1016/S0022-247X(02)00215-9" class="nowrap">doi:10.1016/S0022-247X(02)00215-9</a></td> </tr><tr> <td>[8]</td> <td class="space">Adrian Petruşel, Multivalued weakly Picard operators and applications, Sci. Math. Jpn. 59 (2004), no. 1, 169 – 202. · <a href="/1066.47058" class="nowrap">Zbl 1066.47058</a></td> </tr><tr> <td>[9]</td> <td class="space">André C. M. Ran and Martine C. B. Reurings, A fixed point theorem in partially ordered sets and some applications to matrix equations, Proc. Amer. Math. Soc. 132 (2004), no. 5, 1435 – 1443. · <a href="/1060.47056" class="nowrap">Zbl 1060.47056</a></td> </tr><tr> <td>[10]</td> <td class="space">Ioan A. Rus, Generalized contractions and applications, Cluj University Press, Cluj-Napoca, 2001. · <a href="/0968.54029" class="nowrap">Zbl 0968.54029</a></td> </tr><tr> <td>[11]</td> <td class="space">Ioan A. Rus, Picard operators and applications, Sci. Math. Jpn. 58 (2003), no. 1, 191 – 219. · <a href="/1031.47035" class="nowrap">Zbl 1031.47035</a></td> </tr><tr> <td>[12]</td> <td class="space">Ioan A. Rus, Adrian Petruşel, and Gabriela Petruşel, Fixed point theory: 1950 – 2000. Romanian contributions, House of the Book of Science, Cluj-Napoca, 2002. · <a href="/1005.54037" class="nowrap">Zbl 1005.54037</a></td> </tr><tr> <td>[13]</td> <td class="space">P. P. Zabrejko, \?-metric and \?-normed linear spaces: survey, Collect. Math. 48 (1997), no. 4-6, 825 – 859. Fourth International Conference on Function Spaces (Zielona Góra, 1995). · <a href="/0892.46002" class="nowrap">Zbl 0892.46002</a></td> </tr></table> <div class="reference_disclaimer"> This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching. </div> </div></article> </div></div> </div> </div> <div class="clearfix"></div> </div> </div> <div id="foot"><div class="copyright"> © 2025 <a target="fiz" href="https://www.fiz-karlsruhe.de/en">FIZ Karlsruhe GmbH</a> <a href="/privacy-policy/">Privacy Policy</a> <a href="/legal-notices/">Legal Notices</a> <a href="/terms-conditions/">Terms & Conditions</a> <div class="info"> <ul class="nav"> <li class="mastodon"> <a href="https://mathstodon.xyz/@zbMATH" target="_blank" class="no-new-tab-icon"> <img src="/static/mastodon.png" title="zbMATH at Mathstodon (opens in new tab)" alt="Mastodon logo"> </a> </li> </ul> </div> </div> <div class="clearfix" style="height: 0px;"></div> </div> </div> <script src="https://static.zbmath.org/contrib/jquery/1.9.1/jquery.min.js"></script> <script src="https://static.zbmath.org/contrib/jquery-caret/1.5.2/jquery.caret.min.js"></script> <script src="/static/js/jquery-ui-1.10.1.custom.min.js"></script> <script src="https://static.zbmath.org/contrib/bootstrap/v3.3.7zb1/js/bootstrap.min.js"></script> <script src="https://static.zbmath.org/contrib/bootstrap-lightbox/v0.7.0/bootstrap-lightbox.min.js"></script> <script src="https://static.zbmath.org/contrib/retina/unknown/retina.js"></script> <script src="https://static.zbmath.org/contrib/bootstrap-select/v1.13.14/js/bootstrap-select.min.js"></script> <script> var SCRIPT_ROOT = ""; </script> <script src="/static/scripts.js?v=20240926"> </script> <script src="https://static.zbmath.org/contrib/mathjax/2.7.1/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script> <script type="text/x-mathjax-config"> MathJax.Hub.Config({ "HTML-CSS": { preferredFont: "TeX", availableFonts: [ "STIX", "TeX" ], linebreaks: { automatic: true }, EqnChunk: (MathJax.Hub.Browser.isMobile ? 10 : 50) }, tex2jax: { processEscapes: true, ignoreClass: "tex2jax_ignore|dno" }, TeX: { Macros: { Aut: "\\operatorname{Aut}", Hom: "\\operatorname{Hom}" }, noUndefined: { attributes: { mathcolor: "#039", //"red", mathbackground: "white", //"#FFEEEE", mathsize: "90%" } } }, messageStyle: "none" }); </script> <script type="text/javascript"> $(document).ready(function() { $("#MathInput").stop(true, true).keyup(function() { $.ajax({ url: "/mwsq/", type: "POST", data: { query : $("#MathInput").val() }, dataType: "text" }) .done(function(xml) { $("#MathPreview").html(xml); $(window).resize(); }); }); var press = jQuery.Event("keyup"); press.ctrlKey = false; press.which = 40; $("#MathInput").trigger(press); }); </script> <div id="new_tab_icon" style="display: none"> <span class="glyphicon glyphicon-new-window" aria-hidden="true"></span><span class="sr-only">(opens in new tab)</span></div> </body> </html>