Image and pseduo-inverse of an operator

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











up vote
2
down vote

favorite
2












Let $mathcalH$ be a Hilbert space and $(e_n)_nin Bbb N$ be an orthonormal basis for $mathcalH$.



Define the surjective operator $Tin B(mathcalH)$ such that $Te_2n-1=frac12^ne_1$ and $Te_2n= e_n+1$ for each $ninBbb N$.



There are several questions:



$bullet$ What is the pseudo-inverse $T^dagger$ of $T$?
How is $T^dagger$ define?



$bullet$Decomposing $e_2n-1$ to $ f_n,1oplus f_n,2$ where $f_n,1 in R(T^*)$ and $f_n,2in ker T$ for each $n$. Could we conclude $f_n,1, f_n,2$? ($R(T^*)$ is the image of $T^*$ and $ker T$ is the kernel of $T$)







share|cite|improve this question

























    up vote
    2
    down vote

    favorite
    2












    Let $mathcalH$ be a Hilbert space and $(e_n)_nin Bbb N$ be an orthonormal basis for $mathcalH$.



    Define the surjective operator $Tin B(mathcalH)$ such that $Te_2n-1=frac12^ne_1$ and $Te_2n= e_n+1$ for each $ninBbb N$.



    There are several questions:



    $bullet$ What is the pseudo-inverse $T^dagger$ of $T$?
    How is $T^dagger$ define?



    $bullet$Decomposing $e_2n-1$ to $ f_n,1oplus f_n,2$ where $f_n,1 in R(T^*)$ and $f_n,2in ker T$ for each $n$. Could we conclude $f_n,1, f_n,2$? ($R(T^*)$ is the image of $T^*$ and $ker T$ is the kernel of $T$)







    share|cite|improve this question























      up vote
      2
      down vote

      favorite
      2









      up vote
      2
      down vote

      favorite
      2






      2





      Let $mathcalH$ be a Hilbert space and $(e_n)_nin Bbb N$ be an orthonormal basis for $mathcalH$.



      Define the surjective operator $Tin B(mathcalH)$ such that $Te_2n-1=frac12^ne_1$ and $Te_2n= e_n+1$ for each $ninBbb N$.



      There are several questions:



      $bullet$ What is the pseudo-inverse $T^dagger$ of $T$?
      How is $T^dagger$ define?



      $bullet$Decomposing $e_2n-1$ to $ f_n,1oplus f_n,2$ where $f_n,1 in R(T^*)$ and $f_n,2in ker T$ for each $n$. Could we conclude $f_n,1, f_n,2$? ($R(T^*)$ is the image of $T^*$ and $ker T$ is the kernel of $T$)







      share|cite|improve this question













      Let $mathcalH$ be a Hilbert space and $(e_n)_nin Bbb N$ be an orthonormal basis for $mathcalH$.



      Define the surjective operator $Tin B(mathcalH)$ such that $Te_2n-1=frac12^ne_1$ and $Te_2n= e_n+1$ for each $ninBbb N$.



      There are several questions:



      $bullet$ What is the pseudo-inverse $T^dagger$ of $T$?
      How is $T^dagger$ define?



      $bullet$Decomposing $e_2n-1$ to $ f_n,1oplus f_n,2$ where $f_n,1 in R(T^*)$ and $f_n,2in ker T$ for each $n$. Could we conclude $f_n,1, f_n,2$? ($R(T^*)$ is the image of $T^*$ and $ker T$ is the kernel of $T$)









      share|cite|improve this question












      share|cite|improve this question




      share|cite|improve this question








      edited Jul 25 at 21:49
























      asked Jul 25 at 20:56









      saeed

      13810




      13810




















          1 Answer
          1






          active

          oldest

          votes

















          up vote
          0
          down vote













          The answer to the previous version of the question, which was is $e_2k-1 in R(T^*)$, is no.



          We have
          beginalign
          T^*x &= sum_n=1^infty langle T^*x, e_nrangle e_n \
          &= sum_n=1^infty langle x, Te_nrangle e_n \
          &= sum_n=1^infty langle x, Te_2n-1rangle e_2n-1 + sum_n=1^infty langle x, Te_2n-1rangle e_2n\
          &= langle x, e_1ranglesum_n=1^infty frac12^n e_2n-1 + sum_n=1^infty langle x, e_n+1rangle e_2n
          endalign



          so if $T^*x = e_2k-1$, we must have $$1 = langle T^*x, e_2k-1rangle = langle x, Te_1rangle = frac12^klangle x, e_1rangle$$ so $langle x, e_1rangle = 2^k$ but then



          $$T^*x = 2^ksum_n=1^infty frac12^n e_2n-1 + sum_n=1^infty langle x, e_n+1rangle e_2n ne e_2k-1$$






          share|cite|improve this answer





















            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',
            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%2fmath.stackexchange.com%2fquestions%2f2862814%2fimage-and-pseduo-inverse-of-an-operator%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
            0
            down vote













            The answer to the previous version of the question, which was is $e_2k-1 in R(T^*)$, is no.



            We have
            beginalign
            T^*x &= sum_n=1^infty langle T^*x, e_nrangle e_n \
            &= sum_n=1^infty langle x, Te_nrangle e_n \
            &= sum_n=1^infty langle x, Te_2n-1rangle e_2n-1 + sum_n=1^infty langle x, Te_2n-1rangle e_2n\
            &= langle x, e_1ranglesum_n=1^infty frac12^n e_2n-1 + sum_n=1^infty langle x, e_n+1rangle e_2n
            endalign



            so if $T^*x = e_2k-1$, we must have $$1 = langle T^*x, e_2k-1rangle = langle x, Te_1rangle = frac12^klangle x, e_1rangle$$ so $langle x, e_1rangle = 2^k$ but then



            $$T^*x = 2^ksum_n=1^infty frac12^n e_2n-1 + sum_n=1^infty langle x, e_n+1rangle e_2n ne e_2k-1$$






            share|cite|improve this answer

























              up vote
              0
              down vote













              The answer to the previous version of the question, which was is $e_2k-1 in R(T^*)$, is no.



              We have
              beginalign
              T^*x &= sum_n=1^infty langle T^*x, e_nrangle e_n \
              &= sum_n=1^infty langle x, Te_nrangle e_n \
              &= sum_n=1^infty langle x, Te_2n-1rangle e_2n-1 + sum_n=1^infty langle x, Te_2n-1rangle e_2n\
              &= langle x, e_1ranglesum_n=1^infty frac12^n e_2n-1 + sum_n=1^infty langle x, e_n+1rangle e_2n
              endalign



              so if $T^*x = e_2k-1$, we must have $$1 = langle T^*x, e_2k-1rangle = langle x, Te_1rangle = frac12^klangle x, e_1rangle$$ so $langle x, e_1rangle = 2^k$ but then



              $$T^*x = 2^ksum_n=1^infty frac12^n e_2n-1 + sum_n=1^infty langle x, e_n+1rangle e_2n ne e_2k-1$$






              share|cite|improve this answer























                up vote
                0
                down vote










                up vote
                0
                down vote









                The answer to the previous version of the question, which was is $e_2k-1 in R(T^*)$, is no.



                We have
                beginalign
                T^*x &= sum_n=1^infty langle T^*x, e_nrangle e_n \
                &= sum_n=1^infty langle x, Te_nrangle e_n \
                &= sum_n=1^infty langle x, Te_2n-1rangle e_2n-1 + sum_n=1^infty langle x, Te_2n-1rangle e_2n\
                &= langle x, e_1ranglesum_n=1^infty frac12^n e_2n-1 + sum_n=1^infty langle x, e_n+1rangle e_2n
                endalign



                so if $T^*x = e_2k-1$, we must have $$1 = langle T^*x, e_2k-1rangle = langle x, Te_1rangle = frac12^klangle x, e_1rangle$$ so $langle x, e_1rangle = 2^k$ but then



                $$T^*x = 2^ksum_n=1^infty frac12^n e_2n-1 + sum_n=1^infty langle x, e_n+1rangle e_2n ne e_2k-1$$






                share|cite|improve this answer













                The answer to the previous version of the question, which was is $e_2k-1 in R(T^*)$, is no.



                We have
                beginalign
                T^*x &= sum_n=1^infty langle T^*x, e_nrangle e_n \
                &= sum_n=1^infty langle x, Te_nrangle e_n \
                &= sum_n=1^infty langle x, Te_2n-1rangle e_2n-1 + sum_n=1^infty langle x, Te_2n-1rangle e_2n\
                &= langle x, e_1ranglesum_n=1^infty frac12^n e_2n-1 + sum_n=1^infty langle x, e_n+1rangle e_2n
                endalign



                so if $T^*x = e_2k-1$, we must have $$1 = langle T^*x, e_2k-1rangle = langle x, Te_1rangle = frac12^klangle x, e_1rangle$$ so $langle x, e_1rangle = 2^k$ but then



                $$T^*x = 2^ksum_n=1^infty frac12^n e_2n-1 + sum_n=1^infty langle x, e_n+1rangle e_2n ne e_2k-1$$







                share|cite|improve this answer













                share|cite|improve this answer



                share|cite|improve this answer











                answered Jul 25 at 21:58









                mechanodroid

                22.2k52041




                22.2k52041






















                     

                    draft saved


                    draft discarded


























                     


                    draft saved


                    draft discarded














                    StackExchange.ready(
                    function ()
                    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f2862814%2fimage-and-pseduo-inverse-of-an-operator%23new-answer', 'question_page');

                    );

                    Post as a guest













































































                    Comments

                    Popular posts from this blog

                    What is the equation of a 3D cone with generalised tilt?

                    Color the edges and diagonals of a regular polygon

                    Relationship between determinant of matrix and determinant of adjoint?