Question regarding Galois theory












2














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










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










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










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










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






  • 1




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
















2














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









New contributor




user631697 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.




















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










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










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










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






  • 1




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














2












2








2


1





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









New contributor




user631697 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











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






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user631697 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











share|cite|improve this question









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user631697 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.









share|cite|improve this question




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edited Jan 4 at 17:45









Bernard

118k639112




118k639112






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asked Jan 4 at 16:46









user631697user631697

111




111




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New contributor





user631697 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.






user631697 is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.












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










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










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










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






  • 1




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


















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










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










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










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






  • 1




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
















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




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












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




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












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




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












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




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




1




1




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




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










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