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               <mods:name>
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                     <mods:roleTerm type="text">author</mods:roleTerm>
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                  <mods:namePart>Balacheff, Florent Nicolas</mods:namePart>
               </mods:name>
               <mods:name>
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                  <mods:namePart>Croke, Christopher</mods:namePart>
               </mods:name>
               <mods:name>
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                  <mods:namePart>Katz, Mikhail G.</mods:namePart>
               </mods:name>
               <mods:originInfo>
                  <mods:dateIssued encoding="iso8601">2009</mods:dateIssued>
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               <mods:abstract>We construct a counterexample to a conjectured inequality L ≤ 2D, relating the diameter D and the least length L of a nontrivial closed geodesic, for a Riemannian metric on the 2-sphere. The construction relies on Guillemin's theorem concerning the existence of Zoll surfaces integrating an arbitrary infinitesimal odd deformation of the round metric. Thus the round metric is not optimal for the ratio L/D.</mods:abstract>
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               <mods:accessCondition type="useAndReproduction">open access Aquest material està protegit per drets d'autor i/o drets afins. Podeu utilitzar aquest material en funció del que permet la legislació de drets d'autor i drets afins d'aplicació al vostre cas. Per a d'altres usos heu d'obtenir permís del(s) titular(s) de drets. https://rightsstatements.org/vocab/InC/1.0/</mods:accessCondition>
               <mods:subject>
                  <mods:topic>Closed geodesic</mods:topic>
               </mods:subject>
               <mods:subject>
                  <mods:topic>Diameter</mods:topic>
               </mods:subject>
               <mods:subject>
                  <mods:topic>Guillemin deformation</mods:topic>
               </mods:subject>
               <mods:subject>
                  <mods:topic>Sphere</mods:topic>
               </mods:subject>
               <mods:subject>
                  <mods:topic>Systole</mods:topic>
               </mods:subject>
               <mods:subject>
                  <mods:topic>Zoll surface</mods:topic>
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               <mods:titleInfo>
                  <mods:title>A zoll counterexample to a geodesic length conjecture</mods:title>
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