Question regarding Galois theory












2












$begingroup$


While reading a theorem on Galois theory I came up with this statement "Let $E/F$ be a finite separable extension. Then $E$ is contained in an extension of $K$ which is Galois over $F$.



Now my question is about first statement. Because according as what I know if$E/F$ is a finite extension then it's an algebraic extension and as it's separable hence it's a normal extension also. So $E/F$ is normal separable extension, hence it is Galois. So what am I thinking wrong. It will be really great if you can help me with it










share|cite|improve this question











$endgroup$












  • $begingroup$
    not every separable extension is normal.
    $endgroup$
    – Lord Shark the Unknown
    Jan 4 at 17:02










  • $begingroup$
    I know not every separable extension isn't normal. But isn't every separable finite extension normal. As even finite extension is algebric.
    $endgroup$
    – user631697
    Jan 4 at 17:06










  • $begingroup$
    not every separable finite extension is normal.
    $endgroup$
    – Lord Shark the Unknown
    Jan 4 at 17:07










  • $begingroup$
    It will be great if u can give an example
    $endgroup$
    – user631697
    Jan 4 at 17:08






  • 1




    $begingroup$
    $Bbb Q(sqrt[3]5,)supsetBbb Q$
    $endgroup$
    – Lubin
    Jan 4 at 17:35
















2












$begingroup$


While reading a theorem on Galois theory I came up with this statement "Let $E/F$ be a finite separable extension. Then $E$ is contained in an extension of $K$ which is Galois over $F$.



Now my question is about first statement. Because according as what I know if$E/F$ is a finite extension then it's an algebraic extension and as it's separable hence it's a normal extension also. So $E/F$ is normal separable extension, hence it is Galois. So what am I thinking wrong. It will be really great if you can help me with it










share|cite|improve this question











$endgroup$












  • $begingroup$
    not every separable extension is normal.
    $endgroup$
    – Lord Shark the Unknown
    Jan 4 at 17:02










  • $begingroup$
    I know not every separable extension isn't normal. But isn't every separable finite extension normal. As even finite extension is algebric.
    $endgroup$
    – user631697
    Jan 4 at 17:06










  • $begingroup$
    not every separable finite extension is normal.
    $endgroup$
    – Lord Shark the Unknown
    Jan 4 at 17:07










  • $begingroup$
    It will be great if u can give an example
    $endgroup$
    – user631697
    Jan 4 at 17:08






  • 1




    $begingroup$
    $Bbb Q(sqrt[3]5,)supsetBbb Q$
    $endgroup$
    – Lubin
    Jan 4 at 17:35














2












2








2


1



$begingroup$


While reading a theorem on Galois theory I came up with this statement "Let $E/F$ be a finite separable extension. Then $E$ is contained in an extension of $K$ which is Galois over $F$.



Now my question is about first statement. Because according as what I know if$E/F$ is a finite extension then it's an algebraic extension and as it's separable hence it's a normal extension also. So $E/F$ is normal separable extension, hence it is Galois. So what am I thinking wrong. It will be really great if you can help me with it










share|cite|improve this question











$endgroup$




While reading a theorem on Galois theory I came up with this statement "Let $E/F$ be a finite separable extension. Then $E$ is contained in an extension of $K$ which is Galois over $F$.



Now my question is about first statement. Because according as what I know if$E/F$ is a finite extension then it's an algebraic extension and as it's separable hence it's a normal extension also. So $E/F$ is normal separable extension, hence it is Galois. So what am I thinking wrong. It will be really great if you can help me with it







galois-theory galois-extensions






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Jan 4 at 17:45









Bernard

120k740113




120k740113










asked Jan 4 at 16:46









user631697user631697

111




111












  • $begingroup$
    not every separable extension is normal.
    $endgroup$
    – Lord Shark the Unknown
    Jan 4 at 17:02










  • $begingroup$
    I know not every separable extension isn't normal. But isn't every separable finite extension normal. As even finite extension is algebric.
    $endgroup$
    – user631697
    Jan 4 at 17:06










  • $begingroup$
    not every separable finite extension is normal.
    $endgroup$
    – Lord Shark the Unknown
    Jan 4 at 17:07










  • $begingroup$
    It will be great if u can give an example
    $endgroup$
    – user631697
    Jan 4 at 17:08






  • 1




    $begingroup$
    $Bbb Q(sqrt[3]5,)supsetBbb Q$
    $endgroup$
    – Lubin
    Jan 4 at 17:35


















  • $begingroup$
    not every separable extension is normal.
    $endgroup$
    – Lord Shark the Unknown
    Jan 4 at 17:02










  • $begingroup$
    I know not every separable extension isn't normal. But isn't every separable finite extension normal. As even finite extension is algebric.
    $endgroup$
    – user631697
    Jan 4 at 17:06










  • $begingroup$
    not every separable finite extension is normal.
    $endgroup$
    – Lord Shark the Unknown
    Jan 4 at 17:07










  • $begingroup$
    It will be great if u can give an example
    $endgroup$
    – user631697
    Jan 4 at 17:08






  • 1




    $begingroup$
    $Bbb Q(sqrt[3]5,)supsetBbb Q$
    $endgroup$
    – Lubin
    Jan 4 at 17:35
















$begingroup$
not every separable extension is normal.
$endgroup$
– Lord Shark the Unknown
Jan 4 at 17:02




$begingroup$
not every separable extension is normal.
$endgroup$
– Lord Shark the Unknown
Jan 4 at 17:02












$begingroup$
I know not every separable extension isn't normal. But isn't every separable finite extension normal. As even finite extension is algebric.
$endgroup$
– user631697
Jan 4 at 17:06




$begingroup$
I know not every separable extension isn't normal. But isn't every separable finite extension normal. As even finite extension is algebric.
$endgroup$
– user631697
Jan 4 at 17:06












$begingroup$
not every separable finite extension is normal.
$endgroup$
– Lord Shark the Unknown
Jan 4 at 17:07




$begingroup$
not every separable finite extension is normal.
$endgroup$
– Lord Shark the Unknown
Jan 4 at 17:07












$begingroup$
It will be great if u can give an example
$endgroup$
– user631697
Jan 4 at 17:08




$begingroup$
It will be great if u can give an example
$endgroup$
– user631697
Jan 4 at 17:08




1




1




$begingroup$
$Bbb Q(sqrt[3]5,)supsetBbb Q$
$endgroup$
– Lubin
Jan 4 at 17:35




$begingroup$
$Bbb Q(sqrt[3]5,)supsetBbb Q$
$endgroup$
– Lubin
Jan 4 at 17:35










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
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3061818%2fquestion-regarding-galois-theory%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
















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.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3061818%2fquestion-regarding-galois-theory%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

Human spaceflight

Can not write log (Is /dev/pts mounted?) - openpty in Ubuntu-on-Windows?

File:DeusFollowingSea.jpg