What is the current status of the Arnold conjecture?

The name of the pictureThe name of the pictureThe name of the pictureClash Royale CLAN TAG#URR8PPP











up vote
4
down vote

favorite












Let $(M, omega)$ be a symplectic manifold. V.Arnold conjectured that the number of fixed points of a Hamiltonian symplectomorphism is bounded below by the number of critical points of a smooth function on $M$.



The conjecture was proved in a weaker (homological) version using Floer homology, with two additional conditions:



  1. Compactness of $M$;

  2. Non-degeneracy of the fixed points of the considered Hamiltonian symplectomorphism.

In this setting, it is now fully understood that the number of fixed points is at least the sum of Betti number of $M$.




I am wondering where the general statement stands today. More precisely:



  1. is compactness really necessary to Floer's framework ?

  2. what is known for degenerate Hamiltonians ?

  3. what is known for the critical points lower bound, rather than the Betti sum ?

Thanks a lot










share|cite|improve this question

























    up vote
    4
    down vote

    favorite












    Let $(M, omega)$ be a symplectic manifold. V.Arnold conjectured that the number of fixed points of a Hamiltonian symplectomorphism is bounded below by the number of critical points of a smooth function on $M$.



    The conjecture was proved in a weaker (homological) version using Floer homology, with two additional conditions:



    1. Compactness of $M$;

    2. Non-degeneracy of the fixed points of the considered Hamiltonian symplectomorphism.

    In this setting, it is now fully understood that the number of fixed points is at least the sum of Betti number of $M$.




    I am wondering where the general statement stands today. More precisely:



    1. is compactness really necessary to Floer's framework ?

    2. what is known for degenerate Hamiltonians ?

    3. what is known for the critical points lower bound, rather than the Betti sum ?

    Thanks a lot










    share|cite|improve this question























      up vote
      4
      down vote

      favorite









      up vote
      4
      down vote

      favorite











      Let $(M, omega)$ be a symplectic manifold. V.Arnold conjectured that the number of fixed points of a Hamiltonian symplectomorphism is bounded below by the number of critical points of a smooth function on $M$.



      The conjecture was proved in a weaker (homological) version using Floer homology, with two additional conditions:



      1. Compactness of $M$;

      2. Non-degeneracy of the fixed points of the considered Hamiltonian symplectomorphism.

      In this setting, it is now fully understood that the number of fixed points is at least the sum of Betti number of $M$.




      I am wondering where the general statement stands today. More precisely:



      1. is compactness really necessary to Floer's framework ?

      2. what is known for degenerate Hamiltonians ?

      3. what is known for the critical points lower bound, rather than the Betti sum ?

      Thanks a lot










      share|cite|improve this question













      Let $(M, omega)$ be a symplectic manifold. V.Arnold conjectured that the number of fixed points of a Hamiltonian symplectomorphism is bounded below by the number of critical points of a smooth function on $M$.



      The conjecture was proved in a weaker (homological) version using Floer homology, with two additional conditions:



      1. Compactness of $M$;

      2. Non-degeneracy of the fixed points of the considered Hamiltonian symplectomorphism.

      In this setting, it is now fully understood that the number of fixed points is at least the sum of Betti number of $M$.




      I am wondering where the general statement stands today. More precisely:



      1. is compactness really necessary to Floer's framework ?

      2. what is known for degenerate Hamiltonians ?

      3. what is known for the critical points lower bound, rather than the Betti sum ?

      Thanks a lot







      sg.symplectic-geometry symplectic-topology






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked 1 hour ago









      BrianT

      3756




      3756




















          1 Answer
          1






          active

          oldest

          votes

















          up vote
          4
          down vote













          A recent (2017) overview of the status of Arnold's conjecture is given in The number of Hamiltonian fixed points on symplectically aspherical manifolds.






          share|cite|improve this answer




















          • Thanks. Is there a reason why we always assume compactness of the symplectic manifold ?
            – BrianT
            53 mins ago










          Your Answer




          StackExchange.ifUsing("editor", function ()
          return StackExchange.using("mathjaxEditing", function ()
          StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix)
          StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
          );
          );
          , "mathjax-editing");

          StackExchange.ready(function()
          var channelOptions =
          tags: "".split(" "),
          id: "504"
          ;
          initTagRenderer("".split(" "), "".split(" "), channelOptions);

          StackExchange.using("externalEditor", function()
          // Have to fire editor after snippets, if snippets enabled
          if (StackExchange.settings.snippets.snippetsEnabled)
          StackExchange.using("snippets", function()
          createEditor();
          );

          else
          createEditor();

          );

          function createEditor()
          StackExchange.prepareEditor(
          heartbeatType: 'answer',
          convertImagesToLinks: true,
          noModals: false,
          showLowRepImageUploadWarning: true,
          reputationToPostImages: 10,
          bindNavPrevention: true,
          postfix: "",
          noCode: true, onDemand: true,
          discardSelector: ".discard-answer"
          ,immediatelyShowMarkdownHelp:true
          );



          );













           

          draft saved


          draft discarded


















          StackExchange.ready(
          function ()
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmathoverflow.net%2fquestions%2f312901%2fwhat-is-the-current-status-of-the-arnold-conjecture%23new-answer', 'question_page');

          );

          Post as a guest






























          1 Answer
          1






          active

          oldest

          votes








          1 Answer
          1






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes








          up vote
          4
          down vote













          A recent (2017) overview of the status of Arnold's conjecture is given in The number of Hamiltonian fixed points on symplectically aspherical manifolds.






          share|cite|improve this answer




















          • Thanks. Is there a reason why we always assume compactness of the symplectic manifold ?
            – BrianT
            53 mins ago














          up vote
          4
          down vote













          A recent (2017) overview of the status of Arnold's conjecture is given in The number of Hamiltonian fixed points on symplectically aspherical manifolds.






          share|cite|improve this answer




















          • Thanks. Is there a reason why we always assume compactness of the symplectic manifold ?
            – BrianT
            53 mins ago












          up vote
          4
          down vote










          up vote
          4
          down vote









          A recent (2017) overview of the status of Arnold's conjecture is given in The number of Hamiltonian fixed points on symplectically aspherical manifolds.






          share|cite|improve this answer












          A recent (2017) overview of the status of Arnold's conjecture is given in The number of Hamiltonian fixed points on symplectically aspherical manifolds.







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered 1 hour ago









          Carlo Beenakker

          69.7k8155261




          69.7k8155261











          • Thanks. Is there a reason why we always assume compactness of the symplectic manifold ?
            – BrianT
            53 mins ago
















          • Thanks. Is there a reason why we always assume compactness of the symplectic manifold ?
            – BrianT
            53 mins ago















          Thanks. Is there a reason why we always assume compactness of the symplectic manifold ?
          – BrianT
          53 mins ago




          Thanks. Is there a reason why we always assume compactness of the symplectic manifold ?
          – BrianT
          53 mins ago

















           

          draft saved


          draft discarded















































           


          draft saved


          draft discarded














          StackExchange.ready(
          function ()
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmathoverflow.net%2fquestions%2f312901%2fwhat-is-the-current-status-of-the-arnold-conjecture%23new-answer', 'question_page');

          );

          Post as a guest













































































          Comments

          Popular posts from this blog

          What does second last employer means? [closed]

          List of Gilmore Girls characters

          One-line joke