Linear independence over $mathbb{Z}_p^r$











up vote
0
down vote

favorite












Linearly independent vectors $X_1, X_2, ..., X_n$ over $mathbb{Q}^r$ have integer coordinates. Prove they are linearly independent over $mathbb{Z}_p^r$ for almost every prime $p$. I've been thinking about this problem for a few days and couldn't find any solution.










share|cite|improve this question






















  • Are you suggesting that $(frac{1}{2},frac{1}{2})$ and $(frac{1}{2},frac{1}{3})$ are linearly dependent over $Bbb{Q}$?
    – Servaes
    Nov 23 at 8:21










  • Vectors consist only of integers
    – Quo Si Than
    Nov 23 at 9:41










  • I don't understand the close votes, the question is quite clear.
    – Slade
    Nov 23 at 9:46















up vote
0
down vote

favorite












Linearly independent vectors $X_1, X_2, ..., X_n$ over $mathbb{Q}^r$ have integer coordinates. Prove they are linearly independent over $mathbb{Z}_p^r$ for almost every prime $p$. I've been thinking about this problem for a few days and couldn't find any solution.










share|cite|improve this question






















  • Are you suggesting that $(frac{1}{2},frac{1}{2})$ and $(frac{1}{2},frac{1}{3})$ are linearly dependent over $Bbb{Q}$?
    – Servaes
    Nov 23 at 8:21










  • Vectors consist only of integers
    – Quo Si Than
    Nov 23 at 9:41










  • I don't understand the close votes, the question is quite clear.
    – Slade
    Nov 23 at 9:46













up vote
0
down vote

favorite









up vote
0
down vote

favorite











Linearly independent vectors $X_1, X_2, ..., X_n$ over $mathbb{Q}^r$ have integer coordinates. Prove they are linearly independent over $mathbb{Z}_p^r$ for almost every prime $p$. I've been thinking about this problem for a few days and couldn't find any solution.










share|cite|improve this question













Linearly independent vectors $X_1, X_2, ..., X_n$ over $mathbb{Q}^r$ have integer coordinates. Prove they are linearly independent over $mathbb{Z}_p^r$ for almost every prime $p$. I've been thinking about this problem for a few days and couldn't find any solution.







linear-algebra vector-spaces






share|cite|improve this question













share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked Nov 23 at 7:43









Quo Si Than

1177




1177












  • Are you suggesting that $(frac{1}{2},frac{1}{2})$ and $(frac{1}{2},frac{1}{3})$ are linearly dependent over $Bbb{Q}$?
    – Servaes
    Nov 23 at 8:21










  • Vectors consist only of integers
    – Quo Si Than
    Nov 23 at 9:41










  • I don't understand the close votes, the question is quite clear.
    – Slade
    Nov 23 at 9:46


















  • Are you suggesting that $(frac{1}{2},frac{1}{2})$ and $(frac{1}{2},frac{1}{3})$ are linearly dependent over $Bbb{Q}$?
    – Servaes
    Nov 23 at 8:21










  • Vectors consist only of integers
    – Quo Si Than
    Nov 23 at 9:41










  • I don't understand the close votes, the question is quite clear.
    – Slade
    Nov 23 at 9:46
















Are you suggesting that $(frac{1}{2},frac{1}{2})$ and $(frac{1}{2},frac{1}{3})$ are linearly dependent over $Bbb{Q}$?
– Servaes
Nov 23 at 8:21




Are you suggesting that $(frac{1}{2},frac{1}{2})$ and $(frac{1}{2},frac{1}{3})$ are linearly dependent over $Bbb{Q}$?
– Servaes
Nov 23 at 8:21












Vectors consist only of integers
– Quo Si Than
Nov 23 at 9:41




Vectors consist only of integers
– Quo Si Than
Nov 23 at 9:41












I don't understand the close votes, the question is quite clear.
– Slade
Nov 23 at 9:46




I don't understand the close votes, the question is quite clear.
– Slade
Nov 23 at 9:46










1 Answer
1






active

oldest

votes

















up vote
1
down vote



accepted










If $M$ denotes the matrix sending the standard basis vector $E_i$ to $X_i$, then linear independence is equivalent to $det M neq 0$.



What happens if $det M equiv 0 pmod{p}$ for infinitely many primes $p$?






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: 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%2f3010085%2flinear-independence-over-mathbbz-pr%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








    up vote
    1
    down vote



    accepted










    If $M$ denotes the matrix sending the standard basis vector $E_i$ to $X_i$, then linear independence is equivalent to $det M neq 0$.



    What happens if $det M equiv 0 pmod{p}$ for infinitely many primes $p$?






    share|cite|improve this answer

























      up vote
      1
      down vote



      accepted










      If $M$ denotes the matrix sending the standard basis vector $E_i$ to $X_i$, then linear independence is equivalent to $det M neq 0$.



      What happens if $det M equiv 0 pmod{p}$ for infinitely many primes $p$?






      share|cite|improve this answer























        up vote
        1
        down vote



        accepted







        up vote
        1
        down vote



        accepted






        If $M$ denotes the matrix sending the standard basis vector $E_i$ to $X_i$, then linear independence is equivalent to $det M neq 0$.



        What happens if $det M equiv 0 pmod{p}$ for infinitely many primes $p$?






        share|cite|improve this answer












        If $M$ denotes the matrix sending the standard basis vector $E_i$ to $X_i$, then linear independence is equivalent to $det M neq 0$.



        What happens if $det M equiv 0 pmod{p}$ for infinitely many primes $p$?







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Nov 23 at 9:44









        Slade

        24.7k12564




        24.7k12564






























            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.





            Some of your past answers have not been well-received, and you're in danger of being blocked from answering.


            Please pay close attention to the following guidance:


            • 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.


            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%2f3010085%2flinear-independence-over-mathbbz-pr%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

            Le Mesnil-Réaume

            Ida-Boy-Ed-Garten

            web3.py web3.isConnected() returns false always