(Krull) dimension of dense open subset of finite type algebra over a domain












1












$begingroup$


Let $Dto A$ be a finite type algebra with $D$ a domain. Suppose $Vsubset operatorname{Spec}A$ is open and dense. Is it true that $dim V=dim A$?



I know that if $Xto operatorname{Spec}Bbbk$ is an integral scheme of finite type over a field then for any non-empty open $Usubset X$ we have $dim U=dim X$. Is this possible to globalize to domains?










share|cite|improve this question









$endgroup$

















    1












    $begingroup$


    Let $Dto A$ be a finite type algebra with $D$ a domain. Suppose $Vsubset operatorname{Spec}A$ is open and dense. Is it true that $dim V=dim A$?



    I know that if $Xto operatorname{Spec}Bbbk$ is an integral scheme of finite type over a field then for any non-empty open $Usubset X$ we have $dim U=dim X$. Is this possible to globalize to domains?










    share|cite|improve this question









    $endgroup$















      1












      1








      1





      $begingroup$


      Let $Dto A$ be a finite type algebra with $D$ a domain. Suppose $Vsubset operatorname{Spec}A$ is open and dense. Is it true that $dim V=dim A$?



      I know that if $Xto operatorname{Spec}Bbbk$ is an integral scheme of finite type over a field then for any non-empty open $Usubset X$ we have $dim U=dim X$. Is this possible to globalize to domains?










      share|cite|improve this question









      $endgroup$




      Let $Dto A$ be a finite type algebra with $D$ a domain. Suppose $Vsubset operatorname{Spec}A$ is open and dense. Is it true that $dim V=dim A$?



      I know that if $Xto operatorname{Spec}Bbbk$ is an integral scheme of finite type over a field then for any non-empty open $Usubset X$ we have $dim U=dim X$. Is this possible to globalize to domains?







      algebraic-geometry commutative-algebra affine-schemes krull-dimension






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Jan 18 at 21:26









      ArrowArrow

      5,21931546




      5,21931546






















          1 Answer
          1






          active

          oldest

          votes


















          2












          $begingroup$

          No. For instance, let $D=A=mathbb{Z}_p$ (or any other DVR). Then the open set $Vsubsetoperatorname{Spec} A$ where $p$ does not vanish is open and dense, but $V=operatorname{Spec}mathbb{Q}_p$ so $dim V=0neq 1=dim A$.






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            Ah, the Sierpinksi space! Should have thought of it.
            $endgroup$
            – Arrow
            Jan 19 at 0:15












          Your Answer








          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%2f3078775%2fkrull-dimension-of-dense-open-subset-of-finite-type-algebra-over-a-domain%23new-answer', 'question_page');
          }
          );

          Post as a guest















          Required, but never shown

























          1 Answer
          1






          active

          oldest

          votes








          1 Answer
          1






          active

          oldest

          votes









          active

          oldest

          votes






          active

          oldest

          votes









          2












          $begingroup$

          No. For instance, let $D=A=mathbb{Z}_p$ (or any other DVR). Then the open set $Vsubsetoperatorname{Spec} A$ where $p$ does not vanish is open and dense, but $V=operatorname{Spec}mathbb{Q}_p$ so $dim V=0neq 1=dim A$.






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            Ah, the Sierpinksi space! Should have thought of it.
            $endgroup$
            – Arrow
            Jan 19 at 0:15
















          2












          $begingroup$

          No. For instance, let $D=A=mathbb{Z}_p$ (or any other DVR). Then the open set $Vsubsetoperatorname{Spec} A$ where $p$ does not vanish is open and dense, but $V=operatorname{Spec}mathbb{Q}_p$ so $dim V=0neq 1=dim A$.






          share|cite|improve this answer









          $endgroup$













          • $begingroup$
            Ah, the Sierpinksi space! Should have thought of it.
            $endgroup$
            – Arrow
            Jan 19 at 0:15














          2












          2








          2





          $begingroup$

          No. For instance, let $D=A=mathbb{Z}_p$ (or any other DVR). Then the open set $Vsubsetoperatorname{Spec} A$ where $p$ does not vanish is open and dense, but $V=operatorname{Spec}mathbb{Q}_p$ so $dim V=0neq 1=dim A$.






          share|cite|improve this answer









          $endgroup$



          No. For instance, let $D=A=mathbb{Z}_p$ (or any other DVR). Then the open set $Vsubsetoperatorname{Spec} A$ where $p$ does not vanish is open and dense, but $V=operatorname{Spec}mathbb{Q}_p$ so $dim V=0neq 1=dim A$.







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered Jan 19 at 0:13









          Eric WofseyEric Wofsey

          193k14222353




          193k14222353












          • $begingroup$
            Ah, the Sierpinksi space! Should have thought of it.
            $endgroup$
            – Arrow
            Jan 19 at 0:15


















          • $begingroup$
            Ah, the Sierpinksi space! Should have thought of it.
            $endgroup$
            – Arrow
            Jan 19 at 0:15
















          $begingroup$
          Ah, the Sierpinksi space! Should have thought of it.
          $endgroup$
          – Arrow
          Jan 19 at 0:15




          $begingroup$
          Ah, the Sierpinksi space! Should have thought of it.
          $endgroup$
          – Arrow
          Jan 19 at 0:15


















          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%2f3078775%2fkrull-dimension-of-dense-open-subset-of-finite-type-algebra-over-a-domain%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

          Human spaceflight

          Can not write log (Is /dev/pts mounted?) - openpty in Ubuntu-on-Windows?

          張江高科駅