How to check if permutation induces an element of the Galois group.
$begingroup$
Let $f in mathbb Q[X]$ be irreducible of degree $n$ with zeros $alpha_1,dots,alpha_n in mathbb C$. Further, let $L$ be the splitting field of $f$ and $sigma in S_n$.
Is there an easy way to check if $ alpha_i mapsto alpha_{sigma(i)} $ induces an automorphism of $L$?
number-theory permutations galois-theory symmetric-groups
$endgroup$
add a comment |
$begingroup$
Let $f in mathbb Q[X]$ be irreducible of degree $n$ with zeros $alpha_1,dots,alpha_n in mathbb C$. Further, let $L$ be the splitting field of $f$ and $sigma in S_n$.
Is there an easy way to check if $ alpha_i mapsto alpha_{sigma(i)} $ induces an automorphism of $L$?
number-theory permutations galois-theory symmetric-groups
$endgroup$
$begingroup$
Voted to close as too broad... no, there isn't an easy way to check it.
$endgroup$
– Kenny Lau
Dec 31 '18 at 22:41
add a comment |
$begingroup$
Let $f in mathbb Q[X]$ be irreducible of degree $n$ with zeros $alpha_1,dots,alpha_n in mathbb C$. Further, let $L$ be the splitting field of $f$ and $sigma in S_n$.
Is there an easy way to check if $ alpha_i mapsto alpha_{sigma(i)} $ induces an automorphism of $L$?
number-theory permutations galois-theory symmetric-groups
$endgroup$
Let $f in mathbb Q[X]$ be irreducible of degree $n$ with zeros $alpha_1,dots,alpha_n in mathbb C$. Further, let $L$ be the splitting field of $f$ and $sigma in S_n$.
Is there an easy way to check if $ alpha_i mapsto alpha_{sigma(i)} $ induces an automorphism of $L$?
number-theory permutations galois-theory symmetric-groups
number-theory permutations galois-theory symmetric-groups
asked Dec 11 '18 at 15:57
principal-ideal-domainprincipal-ideal-domain
2,756522
2,756522
$begingroup$
Voted to close as too broad... no, there isn't an easy way to check it.
$endgroup$
– Kenny Lau
Dec 31 '18 at 22:41
add a comment |
$begingroup$
Voted to close as too broad... no, there isn't an easy way to check it.
$endgroup$
– Kenny Lau
Dec 31 '18 at 22:41
$begingroup$
Voted to close as too broad... no, there isn't an easy way to check it.
$endgroup$
– Kenny Lau
Dec 31 '18 at 22:41
$begingroup$
Voted to close as too broad... no, there isn't an easy way to check it.
$endgroup$
– Kenny Lau
Dec 31 '18 at 22:41
add a comment |
0
active
oldest
votes
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
});
}
});
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%2f3035433%2fhow-to-check-if-permutation-induces-an-element-of-the-galois-group%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
0
active
oldest
votes
0
active
oldest
votes
active
oldest
votes
active
oldest
votes
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%2f3035433%2fhow-to-check-if-permutation-induces-an-element-of-the-galois-group%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
$begingroup$
Voted to close as too broad... no, there isn't an easy way to check it.
$endgroup$
– Kenny Lau
Dec 31 '18 at 22:41