absolute value and valuation on the field of formal power series

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











up vote
0
down vote

favorite












I'm currently working on (non-Archimedean) valuations and absolute values. My text states that one example, where I have both a non-Archimedean valuation and a corresponding absolute value is $mathbbC((t))$ , i.e. the field of formal power series with coefficients in $mathbbC$, defined as
$$mathbbC((t))= sum_k=m^infty a_kt^k : m in mathbbZ, a_k in mathbbC.$$



I tried to find how a valuation and an absolute value on this field are defined, but I came up empty-handed.
It would be great if any of you could help me! (If it helps - they mentioned in the same context also $mathbbQ_p$ with the $p$-adic valuation/ absolute value and the completion $mathbbC_p$).







share|cite|improve this question























    up vote
    0
    down vote

    favorite












    I'm currently working on (non-Archimedean) valuations and absolute values. My text states that one example, where I have both a non-Archimedean valuation and a corresponding absolute value is $mathbbC((t))$ , i.e. the field of formal power series with coefficients in $mathbbC$, defined as
    $$mathbbC((t))= sum_k=m^infty a_kt^k : m in mathbbZ, a_k in mathbbC.$$



    I tried to find how a valuation and an absolute value on this field are defined, but I came up empty-handed.
    It would be great if any of you could help me! (If it helps - they mentioned in the same context also $mathbbQ_p$ with the $p$-adic valuation/ absolute value and the completion $mathbbC_p$).







    share|cite|improve this question





















      up vote
      0
      down vote

      favorite









      up vote
      0
      down vote

      favorite











      I'm currently working on (non-Archimedean) valuations and absolute values. My text states that one example, where I have both a non-Archimedean valuation and a corresponding absolute value is $mathbbC((t))$ , i.e. the field of formal power series with coefficients in $mathbbC$, defined as
      $$mathbbC((t))= sum_k=m^infty a_kt^k : m in mathbbZ, a_k in mathbbC.$$



      I tried to find how a valuation and an absolute value on this field are defined, but I came up empty-handed.
      It would be great if any of you could help me! (If it helps - they mentioned in the same context also $mathbbQ_p$ with the $p$-adic valuation/ absolute value and the completion $mathbbC_p$).







      share|cite|improve this question











      I'm currently working on (non-Archimedean) valuations and absolute values. My text states that one example, where I have both a non-Archimedean valuation and a corresponding absolute value is $mathbbC((t))$ , i.e. the field of formal power series with coefficients in $mathbbC$, defined as
      $$mathbbC((t))= sum_k=m^infty a_kt^k : m in mathbbZ, a_k in mathbbC.$$



      I tried to find how a valuation and an absolute value on this field are defined, but I came up empty-handed.
      It would be great if any of you could help me! (If it helps - they mentioned in the same context also $mathbbQ_p$ with the $p$-adic valuation/ absolute value and the completion $mathbbC_p$).









      share|cite|improve this question










      share|cite|improve this question




      share|cite|improve this question









      asked Jul 22 at 12:27









      SallyOwens

      30118




      30118




















          1 Answer
          1






          active

          oldest

          votes

















          up vote
          2
          down vote



          accepted










          The valuation $v(f(t))$ is given by the number of times $t$ divides the power series $f(t)$. The norm is then defined accordingly, i.e. one may define it by setting for example $|f(t)| := e^-v(f(t))$. (More generally, this kind of construction whenever you take a Dedekind domain and consider some nonzero prime ideal of it. In this case the ring is $mathbbC[[t]]$ and the ideal is $(t)$. The case where the domain is $mathbbZ$ and the ideal is $(p)$ gives the usual case of $mathbbQ_p$).






          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%2f2859352%2fabsolute-value-and-valuation-on-the-field-of-formal-power-series%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
            2
            down vote



            accepted










            The valuation $v(f(t))$ is given by the number of times $t$ divides the power series $f(t)$. The norm is then defined accordingly, i.e. one may define it by setting for example $|f(t)| := e^-v(f(t))$. (More generally, this kind of construction whenever you take a Dedekind domain and consider some nonzero prime ideal of it. In this case the ring is $mathbbC[[t]]$ and the ideal is $(t)$. The case where the domain is $mathbbZ$ and the ideal is $(p)$ gives the usual case of $mathbbQ_p$).






            share|cite|improve this answer

























              up vote
              2
              down vote



              accepted










              The valuation $v(f(t))$ is given by the number of times $t$ divides the power series $f(t)$. The norm is then defined accordingly, i.e. one may define it by setting for example $|f(t)| := e^-v(f(t))$. (More generally, this kind of construction whenever you take a Dedekind domain and consider some nonzero prime ideal of it. In this case the ring is $mathbbC[[t]]$ and the ideal is $(t)$. The case where the domain is $mathbbZ$ and the ideal is $(p)$ gives the usual case of $mathbbQ_p$).






              share|cite|improve this answer























                up vote
                2
                down vote



                accepted







                up vote
                2
                down vote



                accepted






                The valuation $v(f(t))$ is given by the number of times $t$ divides the power series $f(t)$. The norm is then defined accordingly, i.e. one may define it by setting for example $|f(t)| := e^-v(f(t))$. (More generally, this kind of construction whenever you take a Dedekind domain and consider some nonzero prime ideal of it. In this case the ring is $mathbbC[[t]]$ and the ideal is $(t)$. The case where the domain is $mathbbZ$ and the ideal is $(p)$ gives the usual case of $mathbbQ_p$).






                share|cite|improve this answer













                The valuation $v(f(t))$ is given by the number of times $t$ divides the power series $f(t)$. The norm is then defined accordingly, i.e. one may define it by setting for example $|f(t)| := e^-v(f(t))$. (More generally, this kind of construction whenever you take a Dedekind domain and consider some nonzero prime ideal of it. In this case the ring is $mathbbC[[t]]$ and the ideal is $(t)$. The case where the domain is $mathbbZ$ and the ideal is $(p)$ gives the usual case of $mathbbQ_p$).







                share|cite|improve this answer













                share|cite|improve this answer



                share|cite|improve this answer











                answered Jul 22 at 12:33









                Gal Porat

                718513




                718513






















                     

                    draft saved


                    draft discarded


























                     


                    draft saved


                    draft discarded














                    StackExchange.ready(
                    function ()
                    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f2859352%2fabsolute-value-and-valuation-on-the-field-of-formal-power-series%23new-answer', 'question_page');

                    );

                    Post as a guest













































































                    Comments

                    Popular posts from this blog

                    Color the edges and diagonals of a regular polygon

                    Relationship between determinant of matrix and determinant of adjoint?

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