Does alternating group $A_5$ is a subgroup of $GL(4,mathbb Z)$?












3














Does alternating group $A_5$ is a subgroup of $GL(4,mathbb Z)$? I know $A_5$ has a 4-dimensional complex representation. But how to prove $A_5$ is a subgroup or not of $GL(4, mathbb Z)$?



In case $GL(4, mathbb Z)$ has a subgroup isomorphic to $A_5$, then I would like to know corresponding generators of that subgroup?



I want to know how many subgroups are there in $GL(4, Bbb Z)$ isomorphic to $A_5$. Is there a unique one?



Thank you so much in advance.










share|cite|improve this question





























    3














    Does alternating group $A_5$ is a subgroup of $GL(4,mathbb Z)$? I know $A_5$ has a 4-dimensional complex representation. But how to prove $A_5$ is a subgroup or not of $GL(4, mathbb Z)$?



    In case $GL(4, mathbb Z)$ has a subgroup isomorphic to $A_5$, then I would like to know corresponding generators of that subgroup?



    I want to know how many subgroups are there in $GL(4, Bbb Z)$ isomorphic to $A_5$. Is there a unique one?



    Thank you so much in advance.










    share|cite|improve this question



























      3












      3








      3







      Does alternating group $A_5$ is a subgroup of $GL(4,mathbb Z)$? I know $A_5$ has a 4-dimensional complex representation. But how to prove $A_5$ is a subgroup or not of $GL(4, mathbb Z)$?



      In case $GL(4, mathbb Z)$ has a subgroup isomorphic to $A_5$, then I would like to know corresponding generators of that subgroup?



      I want to know how many subgroups are there in $GL(4, Bbb Z)$ isomorphic to $A_5$. Is there a unique one?



      Thank you so much in advance.










      share|cite|improve this question















      Does alternating group $A_5$ is a subgroup of $GL(4,mathbb Z)$? I know $A_5$ has a 4-dimensional complex representation. But how to prove $A_5$ is a subgroup or not of $GL(4, mathbb Z)$?



      In case $GL(4, mathbb Z)$ has a subgroup isomorphic to $A_5$, then I would like to know corresponding generators of that subgroup?



      I want to know how many subgroups are there in $GL(4, Bbb Z)$ isomorphic to $A_5$. Is there a unique one?



      Thank you so much in advance.







      group-theory representation-theory






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited 7 hours ago

























      asked 23 hours ago









      mathstudent

      324




      324






















          1 Answer
          1






          active

          oldest

          votes


















          3














          For any $n$, $S_n$ embeds in $GL(n-1,Bbb Z)$. Therefore $A_n$ does too.



          Consider the vectors $v_1,ldots,v_n$ where $v_1,ldots,v_{n-1}$
          are the standard unit vectors in $Bbb Z^{n-1}$ and $v_n=-v_1-cdots-v_{n-1}$.
          By definition $v_1+cdots+v_n=0$. For each permutation $tauin S_n$, there's
          a unique endomorphism of $Bbb Z^{n-1}$ taking each $v_k$ to $v_{tau(k)}$
          (this works due to $v_1+cdots+v_n=0$). So $S_n$ embeds into $text{Aut}(
          Bbb Z^{n-1})
          =GL(n-1,Bbb Z)$
          .



          In fact $A_n$ will embed in $SL(n-1,Bbb Z)$.






          share|cite|improve this answer





















          • Thanks. I would like to know corresponding generators of the subgroup of $GL(4, mathbb Z)$ that is isomorphic to $A_5$ if possible.
            – mathstudent
            22 hours ago












          • What are your favourite generators of $A_5$? @mathstudent
            – Lord Shark the Unknown
            22 hours ago










          • Generators of $A_5$: $<(1 2)(3 4), (1 2 3 4 5)>$. Thanks.
            – mathstudent
            22 hours ago












          • $(1,2,3,4,5)$ maps to $pmatrix{0&0&0&-1\1&0&0&-1\0&1&0&-1\0&0&1&-1}$ etc.
            – Lord Shark the Unknown
            22 hours ago










          • Does $(1,2,5,3,4)$ maps to $pmatrix{0&-1&0&1\1&-1&0&0\0&-1&1&0\0&-1&0&0}$ and $(1,2)(3,4)$ maps to $pmatrix{0&1&0&0\1&0&0&0\0&0&0&1\0&0&1&0}$ ?
            – mathstudent
            22 hours ago













          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%2f3059656%2fdoes-alternating-group-a-5-is-a-subgroup-of-gl4-mathbb-z%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









          3














          For any $n$, $S_n$ embeds in $GL(n-1,Bbb Z)$. Therefore $A_n$ does too.



          Consider the vectors $v_1,ldots,v_n$ where $v_1,ldots,v_{n-1}$
          are the standard unit vectors in $Bbb Z^{n-1}$ and $v_n=-v_1-cdots-v_{n-1}$.
          By definition $v_1+cdots+v_n=0$. For each permutation $tauin S_n$, there's
          a unique endomorphism of $Bbb Z^{n-1}$ taking each $v_k$ to $v_{tau(k)}$
          (this works due to $v_1+cdots+v_n=0$). So $S_n$ embeds into $text{Aut}(
          Bbb Z^{n-1})
          =GL(n-1,Bbb Z)$
          .



          In fact $A_n$ will embed in $SL(n-1,Bbb Z)$.






          share|cite|improve this answer





















          • Thanks. I would like to know corresponding generators of the subgroup of $GL(4, mathbb Z)$ that is isomorphic to $A_5$ if possible.
            – mathstudent
            22 hours ago












          • What are your favourite generators of $A_5$? @mathstudent
            – Lord Shark the Unknown
            22 hours ago










          • Generators of $A_5$: $<(1 2)(3 4), (1 2 3 4 5)>$. Thanks.
            – mathstudent
            22 hours ago












          • $(1,2,3,4,5)$ maps to $pmatrix{0&0&0&-1\1&0&0&-1\0&1&0&-1\0&0&1&-1}$ etc.
            – Lord Shark the Unknown
            22 hours ago










          • Does $(1,2,5,3,4)$ maps to $pmatrix{0&-1&0&1\1&-1&0&0\0&-1&1&0\0&-1&0&0}$ and $(1,2)(3,4)$ maps to $pmatrix{0&1&0&0\1&0&0&0\0&0&0&1\0&0&1&0}$ ?
            – mathstudent
            22 hours ago


















          3














          For any $n$, $S_n$ embeds in $GL(n-1,Bbb Z)$. Therefore $A_n$ does too.



          Consider the vectors $v_1,ldots,v_n$ where $v_1,ldots,v_{n-1}$
          are the standard unit vectors in $Bbb Z^{n-1}$ and $v_n=-v_1-cdots-v_{n-1}$.
          By definition $v_1+cdots+v_n=0$. For each permutation $tauin S_n$, there's
          a unique endomorphism of $Bbb Z^{n-1}$ taking each $v_k$ to $v_{tau(k)}$
          (this works due to $v_1+cdots+v_n=0$). So $S_n$ embeds into $text{Aut}(
          Bbb Z^{n-1})
          =GL(n-1,Bbb Z)$
          .



          In fact $A_n$ will embed in $SL(n-1,Bbb Z)$.






          share|cite|improve this answer





















          • Thanks. I would like to know corresponding generators of the subgroup of $GL(4, mathbb Z)$ that is isomorphic to $A_5$ if possible.
            – mathstudent
            22 hours ago












          • What are your favourite generators of $A_5$? @mathstudent
            – Lord Shark the Unknown
            22 hours ago










          • Generators of $A_5$: $<(1 2)(3 4), (1 2 3 4 5)>$. Thanks.
            – mathstudent
            22 hours ago












          • $(1,2,3,4,5)$ maps to $pmatrix{0&0&0&-1\1&0&0&-1\0&1&0&-1\0&0&1&-1}$ etc.
            – Lord Shark the Unknown
            22 hours ago










          • Does $(1,2,5,3,4)$ maps to $pmatrix{0&-1&0&1\1&-1&0&0\0&-1&1&0\0&-1&0&0}$ and $(1,2)(3,4)$ maps to $pmatrix{0&1&0&0\1&0&0&0\0&0&0&1\0&0&1&0}$ ?
            – mathstudent
            22 hours ago
















          3












          3








          3






          For any $n$, $S_n$ embeds in $GL(n-1,Bbb Z)$. Therefore $A_n$ does too.



          Consider the vectors $v_1,ldots,v_n$ where $v_1,ldots,v_{n-1}$
          are the standard unit vectors in $Bbb Z^{n-1}$ and $v_n=-v_1-cdots-v_{n-1}$.
          By definition $v_1+cdots+v_n=0$. For each permutation $tauin S_n$, there's
          a unique endomorphism of $Bbb Z^{n-1}$ taking each $v_k$ to $v_{tau(k)}$
          (this works due to $v_1+cdots+v_n=0$). So $S_n$ embeds into $text{Aut}(
          Bbb Z^{n-1})
          =GL(n-1,Bbb Z)$
          .



          In fact $A_n$ will embed in $SL(n-1,Bbb Z)$.






          share|cite|improve this answer












          For any $n$, $S_n$ embeds in $GL(n-1,Bbb Z)$. Therefore $A_n$ does too.



          Consider the vectors $v_1,ldots,v_n$ where $v_1,ldots,v_{n-1}$
          are the standard unit vectors in $Bbb Z^{n-1}$ and $v_n=-v_1-cdots-v_{n-1}$.
          By definition $v_1+cdots+v_n=0$. For each permutation $tauin S_n$, there's
          a unique endomorphism of $Bbb Z^{n-1}$ taking each $v_k$ to $v_{tau(k)}$
          (this works due to $v_1+cdots+v_n=0$). So $S_n$ embeds into $text{Aut}(
          Bbb Z^{n-1})
          =GL(n-1,Bbb Z)$
          .



          In fact $A_n$ will embed in $SL(n-1,Bbb Z)$.







          share|cite|improve this answer












          share|cite|improve this answer



          share|cite|improve this answer










          answered 23 hours ago









          Lord Shark the Unknown

          101k958132




          101k958132












          • Thanks. I would like to know corresponding generators of the subgroup of $GL(4, mathbb Z)$ that is isomorphic to $A_5$ if possible.
            – mathstudent
            22 hours ago












          • What are your favourite generators of $A_5$? @mathstudent
            – Lord Shark the Unknown
            22 hours ago










          • Generators of $A_5$: $<(1 2)(3 4), (1 2 3 4 5)>$. Thanks.
            – mathstudent
            22 hours ago












          • $(1,2,3,4,5)$ maps to $pmatrix{0&0&0&-1\1&0&0&-1\0&1&0&-1\0&0&1&-1}$ etc.
            – Lord Shark the Unknown
            22 hours ago










          • Does $(1,2,5,3,4)$ maps to $pmatrix{0&-1&0&1\1&-1&0&0\0&-1&1&0\0&-1&0&0}$ and $(1,2)(3,4)$ maps to $pmatrix{0&1&0&0\1&0&0&0\0&0&0&1\0&0&1&0}$ ?
            – mathstudent
            22 hours ago




















          • Thanks. I would like to know corresponding generators of the subgroup of $GL(4, mathbb Z)$ that is isomorphic to $A_5$ if possible.
            – mathstudent
            22 hours ago












          • What are your favourite generators of $A_5$? @mathstudent
            – Lord Shark the Unknown
            22 hours ago










          • Generators of $A_5$: $<(1 2)(3 4), (1 2 3 4 5)>$. Thanks.
            – mathstudent
            22 hours ago












          • $(1,2,3,4,5)$ maps to $pmatrix{0&0&0&-1\1&0&0&-1\0&1&0&-1\0&0&1&-1}$ etc.
            – Lord Shark the Unknown
            22 hours ago










          • Does $(1,2,5,3,4)$ maps to $pmatrix{0&-1&0&1\1&-1&0&0\0&-1&1&0\0&-1&0&0}$ and $(1,2)(3,4)$ maps to $pmatrix{0&1&0&0\1&0&0&0\0&0&0&1\0&0&1&0}$ ?
            – mathstudent
            22 hours ago


















          Thanks. I would like to know corresponding generators of the subgroup of $GL(4, mathbb Z)$ that is isomorphic to $A_5$ if possible.
          – mathstudent
          22 hours ago






          Thanks. I would like to know corresponding generators of the subgroup of $GL(4, mathbb Z)$ that is isomorphic to $A_5$ if possible.
          – mathstudent
          22 hours ago














          What are your favourite generators of $A_5$? @mathstudent
          – Lord Shark the Unknown
          22 hours ago




          What are your favourite generators of $A_5$? @mathstudent
          – Lord Shark the Unknown
          22 hours ago












          Generators of $A_5$: $<(1 2)(3 4), (1 2 3 4 5)>$. Thanks.
          – mathstudent
          22 hours ago






          Generators of $A_5$: $<(1 2)(3 4), (1 2 3 4 5)>$. Thanks.
          – mathstudent
          22 hours ago














          $(1,2,3,4,5)$ maps to $pmatrix{0&0&0&-1\1&0&0&-1\0&1&0&-1\0&0&1&-1}$ etc.
          – Lord Shark the Unknown
          22 hours ago




          $(1,2,3,4,5)$ maps to $pmatrix{0&0&0&-1\1&0&0&-1\0&1&0&-1\0&0&1&-1}$ etc.
          – Lord Shark the Unknown
          22 hours ago












          Does $(1,2,5,3,4)$ maps to $pmatrix{0&-1&0&1\1&-1&0&0\0&-1&1&0\0&-1&0&0}$ and $(1,2)(3,4)$ maps to $pmatrix{0&1&0&0\1&0&0&0\0&0&0&1\0&0&1&0}$ ?
          – mathstudent
          22 hours ago






          Does $(1,2,5,3,4)$ maps to $pmatrix{0&-1&0&1\1&-1&0&0\0&-1&1&0\0&-1&0&0}$ and $(1,2)(3,4)$ maps to $pmatrix{0&1&0&0\1&0&0&0\0&0&0&1\0&0&1&0}$ ?
          – mathstudent
          22 hours ago




















          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%2f3059656%2fdoes-alternating-group-a-5-is-a-subgroup-of-gl4-mathbb-z%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

          1300-talet

          1300-talet

          Display a custom attribute below product name in the front-end Magento 1.9.3.8