Density in fractional Sobolev space












1












$begingroup$


Suppose $sin (0,1)$, $D$ is an open set in $mathbb{R}^d$. Define
$$
H^s=(1-Delta)^{-s/2} L^2(mathbb{R}^d),
$$



$$
H_D^s={fin H^s: f=0 a.e. on D^c}.
$$



Q: Is $C_c^infty(D)$ dense in $H_D^s$(with norm $|cdot|_{H^s}$) for any open set $D$?



Is there any element reference?










share|cite|improve this question









$endgroup$

















    1












    $begingroup$


    Suppose $sin (0,1)$, $D$ is an open set in $mathbb{R}^d$. Define
    $$
    H^s=(1-Delta)^{-s/2} L^2(mathbb{R}^d),
    $$



    $$
    H_D^s={fin H^s: f=0 a.e. on D^c}.
    $$



    Q: Is $C_c^infty(D)$ dense in $H_D^s$(with norm $|cdot|_{H^s}$) for any open set $D$?



    Is there any element reference?










    share|cite|improve this question









    $endgroup$















      1












      1








      1





      $begingroup$


      Suppose $sin (0,1)$, $D$ is an open set in $mathbb{R}^d$. Define
      $$
      H^s=(1-Delta)^{-s/2} L^2(mathbb{R}^d),
      $$



      $$
      H_D^s={fin H^s: f=0 a.e. on D^c}.
      $$



      Q: Is $C_c^infty(D)$ dense in $H_D^s$(with norm $|cdot|_{H^s}$) for any open set $D$?



      Is there any element reference?










      share|cite|improve this question









      $endgroup$




      Suppose $sin (0,1)$, $D$ is an open set in $mathbb{R}^d$. Define
      $$
      H^s=(1-Delta)^{-s/2} L^2(mathbb{R}^d),
      $$



      $$
      H_D^s={fin H^s: f=0 a.e. on D^c}.
      $$



      Q: Is $C_c^infty(D)$ dense in $H_D^s$(with norm $|cdot|_{H^s}$) for any open set $D$?



      Is there any element reference?







      functional-analysis pde fractional-sobolev-spaces






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Jan 23 at 19:45









      Guohuan ZhaoGuohuan Zhao

      283




      283






















          0






          active

          oldest

          votes











          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: "69"
          };
          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',
          autoActivateHeartbeat: false,
          convertImagesToLinks: true,
          noModals: true,
          showLowRepImageUploadWarning: true,
          reputationToPostImages: 10,
          bindNavPrevention: true,
          postfix: "",
          imageUploader: {
          brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
          contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
          allowUrls: true
          },
          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%2fmath.stackexchange.com%2fquestions%2f3084971%2fdensity-in-fractional-sobolev-space%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown

























          0






          active

          oldest

          votes








          0






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes
















          draft saved

          draft discarded




















































          Thanks for contributing an answer to Mathematics Stack Exchange!


          • Please be sure to answer the question. Provide details and share your research!

          But avoid



          • Asking for help, clarification, or responding to other answers.

          • Making statements based on opinion; back them up with references or personal experience.


          Use MathJax to format equations. MathJax reference.


          To learn more, see our tips on writing great answers.




          draft saved


          draft discarded














          StackExchange.ready(
          function () {
          StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3084971%2fdensity-in-fractional-sobolev-space%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown





















































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown

































          Required, but never shown














          Required, but never shown












          Required, but never shown







          Required, but never shown







          Popular posts from this blog

          Mario Kart Wii

          What does “Dominus providebit” mean?

          The Binding of Isaac: Rebirth/Afterbirth