Proving $X/Ycong mathbb{Z}_p^times$
$begingroup$
I would like to show that $X=GA_1(mathbb{Z}_p)$ has a normal subgroup $Y$ that is isomorphic to $mathbb{Z}_p$, that $X/Ycong mathbb{Z}_p^times$ but $Xnotcong mathbb{Z}_ptimes mathbb{Z}_p^times $.
$GA(mathbb{Z}_p)$ is the general affine group of matrices $1times1$ over the field $mathbb{Z}$ mod $p$ (prime) (link). Also $mathbb{Z}_p^times$ is the Multiplicative group of integers modulo $p$ (link).
I know that in order to prove $X/Ycong mathbb{Z}_p^times$ I need to find $Y$ so there is $phi : X/Y to mathbb{Z}_p^times$. But I can't think of $Y$ and $phi$ in order to solve this problem. Which group $Y$ and function $phi$ should solve it and how?
abstract-algebra group-theory
$endgroup$
add a comment |
$begingroup$
I would like to show that $X=GA_1(mathbb{Z}_p)$ has a normal subgroup $Y$ that is isomorphic to $mathbb{Z}_p$, that $X/Ycong mathbb{Z}_p^times$ but $Xnotcong mathbb{Z}_ptimes mathbb{Z}_p^times $.
$GA(mathbb{Z}_p)$ is the general affine group of matrices $1times1$ over the field $mathbb{Z}$ mod $p$ (prime) (link). Also $mathbb{Z}_p^times$ is the Multiplicative group of integers modulo $p$ (link).
I know that in order to prove $X/Ycong mathbb{Z}_p^times$ I need to find $Y$ so there is $phi : X/Y to mathbb{Z}_p^times$. But I can't think of $Y$ and $phi$ in order to solve this problem. Which group $Y$ and function $phi$ should solve it and how?
abstract-algebra group-theory
$endgroup$
add a comment |
$begingroup$
I would like to show that $X=GA_1(mathbb{Z}_p)$ has a normal subgroup $Y$ that is isomorphic to $mathbb{Z}_p$, that $X/Ycong mathbb{Z}_p^times$ but $Xnotcong mathbb{Z}_ptimes mathbb{Z}_p^times $.
$GA(mathbb{Z}_p)$ is the general affine group of matrices $1times1$ over the field $mathbb{Z}$ mod $p$ (prime) (link). Also $mathbb{Z}_p^times$ is the Multiplicative group of integers modulo $p$ (link).
I know that in order to prove $X/Ycong mathbb{Z}_p^times$ I need to find $Y$ so there is $phi : X/Y to mathbb{Z}_p^times$. But I can't think of $Y$ and $phi$ in order to solve this problem. Which group $Y$ and function $phi$ should solve it and how?
abstract-algebra group-theory
$endgroup$
I would like to show that $X=GA_1(mathbb{Z}_p)$ has a normal subgroup $Y$ that is isomorphic to $mathbb{Z}_p$, that $X/Ycong mathbb{Z}_p^times$ but $Xnotcong mathbb{Z}_ptimes mathbb{Z}_p^times $.
$GA(mathbb{Z}_p)$ is the general affine group of matrices $1times1$ over the field $mathbb{Z}$ mod $p$ (prime) (link). Also $mathbb{Z}_p^times$ is the Multiplicative group of integers modulo $p$ (link).
I know that in order to prove $X/Ycong mathbb{Z}_p^times$ I need to find $Y$ so there is $phi : X/Y to mathbb{Z}_p^times$. But I can't think of $Y$ and $phi$ in order to solve this problem. Which group $Y$ and function $phi$ should solve it and how?
abstract-algebra group-theory
abstract-algebra group-theory
asked Jan 12 at 17:13
vesiivesii
3978
3978
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
$newcommand{Set}[1]{left{ #1 right}}$
It is convenient to think of $X$ as the group of matrices
$$
Set{begin{bmatrix}a & b\
0 & 1end{bmatrix}
a in mathbb{Z}_p^{times}, b in mathbb{Z}_p}.
$$
Hint 1
To find $Y$, take the elements with $a = 1$.
Hint 2
To find $phi$, consider the map that takes the matrix $begin{bmatrix}a & b\0 & 1end{bmatrix}$ to $a$.
$endgroup$
$begingroup$
By your hint we get $Y=left{ begin{pmatrix}1 & b\ 0 & 1 end{pmatrix}|binmathbb{Z}_{p}right}$ but why $Y=mathbb{Z}_p$ and $X/Ycongmathbb{Z}_{p}^{times}$?
$endgroup$
– vesii
Jan 12 at 17:43
add a comment |
Your Answer
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
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3071132%2fproving-x-y-cong-mathbbz-p-times%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
$begingroup$
$newcommand{Set}[1]{left{ #1 right}}$
It is convenient to think of $X$ as the group of matrices
$$
Set{begin{bmatrix}a & b\
0 & 1end{bmatrix}
a in mathbb{Z}_p^{times}, b in mathbb{Z}_p}.
$$
Hint 1
To find $Y$, take the elements with $a = 1$.
Hint 2
To find $phi$, consider the map that takes the matrix $begin{bmatrix}a & b\0 & 1end{bmatrix}$ to $a$.
$endgroup$
$begingroup$
By your hint we get $Y=left{ begin{pmatrix}1 & b\ 0 & 1 end{pmatrix}|binmathbb{Z}_{p}right}$ but why $Y=mathbb{Z}_p$ and $X/Ycongmathbb{Z}_{p}^{times}$?
$endgroup$
– vesii
Jan 12 at 17:43
add a comment |
$begingroup$
$newcommand{Set}[1]{left{ #1 right}}$
It is convenient to think of $X$ as the group of matrices
$$
Set{begin{bmatrix}a & b\
0 & 1end{bmatrix}
a in mathbb{Z}_p^{times}, b in mathbb{Z}_p}.
$$
Hint 1
To find $Y$, take the elements with $a = 1$.
Hint 2
To find $phi$, consider the map that takes the matrix $begin{bmatrix}a & b\0 & 1end{bmatrix}$ to $a$.
$endgroup$
$begingroup$
By your hint we get $Y=left{ begin{pmatrix}1 & b\ 0 & 1 end{pmatrix}|binmathbb{Z}_{p}right}$ but why $Y=mathbb{Z}_p$ and $X/Ycongmathbb{Z}_{p}^{times}$?
$endgroup$
– vesii
Jan 12 at 17:43
add a comment |
$begingroup$
$newcommand{Set}[1]{left{ #1 right}}$
It is convenient to think of $X$ as the group of matrices
$$
Set{begin{bmatrix}a & b\
0 & 1end{bmatrix}
a in mathbb{Z}_p^{times}, b in mathbb{Z}_p}.
$$
Hint 1
To find $Y$, take the elements with $a = 1$.
Hint 2
To find $phi$, consider the map that takes the matrix $begin{bmatrix}a & b\0 & 1end{bmatrix}$ to $a$.
$endgroup$
$newcommand{Set}[1]{left{ #1 right}}$
It is convenient to think of $X$ as the group of matrices
$$
Set{begin{bmatrix}a & b\
0 & 1end{bmatrix}
a in mathbb{Z}_p^{times}, b in mathbb{Z}_p}.
$$
Hint 1
To find $Y$, take the elements with $a = 1$.
Hint 2
To find $phi$, consider the map that takes the matrix $begin{bmatrix}a & b\0 & 1end{bmatrix}$ to $a$.
edited Jan 12 at 17:34
answered Jan 12 at 17:32
Andreas CarantiAndreas Caranti
57.3k34497
57.3k34497
$begingroup$
By your hint we get $Y=left{ begin{pmatrix}1 & b\ 0 & 1 end{pmatrix}|binmathbb{Z}_{p}right}$ but why $Y=mathbb{Z}_p$ and $X/Ycongmathbb{Z}_{p}^{times}$?
$endgroup$
– vesii
Jan 12 at 17:43
add a comment |
$begingroup$
By your hint we get $Y=left{ begin{pmatrix}1 & b\ 0 & 1 end{pmatrix}|binmathbb{Z}_{p}right}$ but why $Y=mathbb{Z}_p$ and $X/Ycongmathbb{Z}_{p}^{times}$?
$endgroup$
– vesii
Jan 12 at 17:43
$begingroup$
By your hint we get $Y=left{ begin{pmatrix}1 & b\ 0 & 1 end{pmatrix}|binmathbb{Z}_{p}right}$ but why $Y=mathbb{Z}_p$ and $X/Ycongmathbb{Z}_{p}^{times}$?
$endgroup$
– vesii
Jan 12 at 17:43
$begingroup$
By your hint we get $Y=left{ begin{pmatrix}1 & b\ 0 & 1 end{pmatrix}|binmathbb{Z}_{p}right}$ but why $Y=mathbb{Z}_p$ and $X/Ycongmathbb{Z}_{p}^{times}$?
$endgroup$
– vesii
Jan 12 at 17:43
add a comment |
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.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3071132%2fproving-x-y-cong-mathbbz-p-times%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
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