K Theory of $C^*$ algebras I, Higson's notes The 2019 Stack Overflow Developer Survey Results Are InK-theory for non-separable C*-algebrasWhy must trivial extension of C*-algebra be split Short Exact Sequence?Exact sequence of tensor productDirect limit of certain $C^*$ algebras is simpleTopological K-Theory-Spectrum for $C^*$-Algebrasinductive limit of nuclear c*algebras is nuclearInterpretation of the $K$-groups of a $C^*$-algebra.Elliott-Natsume-Nest proof of Bott periodicity for $K$-theory of $C^ast$-algebrasShort exact sequence in $K_0$ of non unital rings.$K$-Theory of operators I, Higson notes

Idiomatic way to prevent slicing?

Manuscript was "unsubmitted" because the manuscript was deposited in Arxiv Preprints

How long do I have to send payment?

aging parents with no investments

Could JWST stay at L2 "forever"?

How are circuits which use complex ICs normally simulated?

What effect does the “loading” weapon property have in practical terms?

Unbreakable Formation vs. Cry of the Carnarium

Where to refill my bottle in India?

Why is Grand Jury testimony secret?

What tool would a Roman-age civilization have to grind silver and other metals into dust?

Does duplicating a spell with Wish count as casting that spell?

How come people say “Would of”?

How can I create a character who can assume the widest possible range of creature sizes?

Is domain driven design an anti-SQL pattern?

How to reverse every other sublist of a list?

Is there a name of the flying bionic bird?

What is the steepest angle that a canal can be traversable without locks?

Landlord wants to switch my lease to a "Land contract" to "get back at the city"

"Riffle" two strings

Is three citations per paragraph excessive for undergraduate research paper?

Why can Shazam do this?

What can other administrators access on my machine?

The difference between dialogue marks



K Theory of $C^*$ algebras I, Higson's notes



The 2019 Stack Overflow Developer Survey Results Are InK-theory for non-separable C*-algebrasWhy must trivial extension of C*-algebra be split Short Exact Sequence?Exact sequence of tensor productDirect limit of certain $C^*$ algebras is simpleTopological K-Theory-Spectrum for $C^*$-Algebrasinductive limit of nuclear c*algebras is nuclearInterpretation of the $K$-groups of a $C^*$-algebra.Elliott-Natsume-Nest proof of Bott periodicity for $K$-theory of $C^ast$-algebrasShort exact sequence in $K_0$ of non unital rings.$K$-Theory of operators I, Higson notes










1












$begingroup$



Let $B$ be a $C^*$ algebra, and $A(B)$ denote the algebra of bounded continuous functions from $[1,infty)$ to $B$. Let $I(B)$ be the ideal of functions which vanish at infinity. Let $Q(B)$ be the quotient $C^*$ algebra.



We have an exact sequence
$$0 rightarrow I(B) rightarrow A(B) rightarrow Q(B) rightarrow 0$$



Claim:
$$K_0(A(B)) cong K_0(Q(B))$$





I know: from algebraic $K$ theory of rings we have a middle exact sequence, and from homotopy invaraince, that $K_0(I(B)) = 0$.



How does one deduce surjectivity of $K_0(A(B)) rightarrow K_0(Q(B))$?



I suppose this follows from six-term exact sequence of $C^*$ algebras. I wonder if there is an elementary way to see this.




Reference: Page 47 of Higson's notes.










share|cite|improve this question











$endgroup$
















    1












    $begingroup$



    Let $B$ be a $C^*$ algebra, and $A(B)$ denote the algebra of bounded continuous functions from $[1,infty)$ to $B$. Let $I(B)$ be the ideal of functions which vanish at infinity. Let $Q(B)$ be the quotient $C^*$ algebra.



    We have an exact sequence
    $$0 rightarrow I(B) rightarrow A(B) rightarrow Q(B) rightarrow 0$$



    Claim:
    $$K_0(A(B)) cong K_0(Q(B))$$





    I know: from algebraic $K$ theory of rings we have a middle exact sequence, and from homotopy invaraince, that $K_0(I(B)) = 0$.



    How does one deduce surjectivity of $K_0(A(B)) rightarrow K_0(Q(B))$?



    I suppose this follows from six-term exact sequence of $C^*$ algebras. I wonder if there is an elementary way to see this.




    Reference: Page 47 of Higson's notes.










    share|cite|improve this question











    $endgroup$














      1












      1








      1





      $begingroup$



      Let $B$ be a $C^*$ algebra, and $A(B)$ denote the algebra of bounded continuous functions from $[1,infty)$ to $B$. Let $I(B)$ be the ideal of functions which vanish at infinity. Let $Q(B)$ be the quotient $C^*$ algebra.



      We have an exact sequence
      $$0 rightarrow I(B) rightarrow A(B) rightarrow Q(B) rightarrow 0$$



      Claim:
      $$K_0(A(B)) cong K_0(Q(B))$$





      I know: from algebraic $K$ theory of rings we have a middle exact sequence, and from homotopy invaraince, that $K_0(I(B)) = 0$.



      How does one deduce surjectivity of $K_0(A(B)) rightarrow K_0(Q(B))$?



      I suppose this follows from six-term exact sequence of $C^*$ algebras. I wonder if there is an elementary way to see this.




      Reference: Page 47 of Higson's notes.










      share|cite|improve this question











      $endgroup$





      Let $B$ be a $C^*$ algebra, and $A(B)$ denote the algebra of bounded continuous functions from $[1,infty)$ to $B$. Let $I(B)$ be the ideal of functions which vanish at infinity. Let $Q(B)$ be the quotient $C^*$ algebra.



      We have an exact sequence
      $$0 rightarrow I(B) rightarrow A(B) rightarrow Q(B) rightarrow 0$$



      Claim:
      $$K_0(A(B)) cong K_0(Q(B))$$





      I know: from algebraic $K$ theory of rings we have a middle exact sequence, and from homotopy invaraince, that $K_0(I(B)) = 0$.



      How does one deduce surjectivity of $K_0(A(B)) rightarrow K_0(Q(B))$?



      I suppose this follows from six-term exact sequence of $C^*$ algebras. I wonder if there is an elementary way to see this.




      Reference: Page 47 of Higson's notes.







      operator-algebras k-theory topological-k-theory algebraic-k-theory






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited Apr 6 at 17:37







      CL.

















      asked Apr 5 at 16:08









      CL.CL.

      2,3222925




      2,3222925




















          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%2f3176108%2fk-theory-of-c-algebras-i-higsons-notes%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%2f3176108%2fk-theory-of-c-algebras-i-higsons-notes%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

          Bosc Connection Yimello Approaching Angry The produce zaps the market. 구성 기록되다 변경...

          WordPress Information needed

          Hidroelektrana Sadržaj Povijest | Podjela hidroelektrana | Snaga dobivena u hidroelektranama | Dijelovi hidroelektrane | Uloga hidroelektrana u suvremenom svijetu | Prednosti hidroelektrana | Nedostaci hidroelektrana | Države s najvećom proizvodnjom hidro-električne energije | Deset najvećih hidroelektrana u svijetu | Hidroelektrane u Hrvatskoj | Izvori | Poveznice | Vanjske poveznice | Navigacijski izbornikTechnical Report, Version 2Zajedničkom poslužiteljuHidroelektranaHEP Proizvodnja d.o.o. - Hidroelektrane u Hrvatskoj