Must these two vector spaces always be isomorphic?












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Suppose $V$ and $W$ are vector spaces over $mathbb{Q}$ and the cardinality of $V$ is the same as the cardinality of $W$. Must $V$ and $W$ be isomorphic?










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  • 4




    $begingroup$
    What is the cardinality of $mathbb{Q}?$ What is the cardinality of $mathbb{Q}^2?$
    $endgroup$
    – saulspatz
    Jan 13 at 17:01






  • 2




    $begingroup$
    You could have two vector spaces of the same cardinality but different dimension so not isomorphic
    $endgroup$
    – J. W. Tanner
    Jan 13 at 17:02
















0












$begingroup$


Suppose $V$ and $W$ are vector spaces over $mathbb{Q}$ and the cardinality of $V$ is the same as the cardinality of $W$. Must $V$ and $W$ be isomorphic?










share|cite|improve this question









$endgroup$








  • 4




    $begingroup$
    What is the cardinality of $mathbb{Q}?$ What is the cardinality of $mathbb{Q}^2?$
    $endgroup$
    – saulspatz
    Jan 13 at 17:01






  • 2




    $begingroup$
    You could have two vector spaces of the same cardinality but different dimension so not isomorphic
    $endgroup$
    – J. W. Tanner
    Jan 13 at 17:02














0












0








0





$begingroup$


Suppose $V$ and $W$ are vector spaces over $mathbb{Q}$ and the cardinality of $V$ is the same as the cardinality of $W$. Must $V$ and $W$ be isomorphic?










share|cite|improve this question









$endgroup$




Suppose $V$ and $W$ are vector spaces over $mathbb{Q}$ and the cardinality of $V$ is the same as the cardinality of $W$. Must $V$ and $W$ be isomorphic?







linear-algebra






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share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked Jan 13 at 16:54









FortoxFortox

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6718








  • 4




    $begingroup$
    What is the cardinality of $mathbb{Q}?$ What is the cardinality of $mathbb{Q}^2?$
    $endgroup$
    – saulspatz
    Jan 13 at 17:01






  • 2




    $begingroup$
    You could have two vector spaces of the same cardinality but different dimension so not isomorphic
    $endgroup$
    – J. W. Tanner
    Jan 13 at 17:02














  • 4




    $begingroup$
    What is the cardinality of $mathbb{Q}?$ What is the cardinality of $mathbb{Q}^2?$
    $endgroup$
    – saulspatz
    Jan 13 at 17:01






  • 2




    $begingroup$
    You could have two vector spaces of the same cardinality but different dimension so not isomorphic
    $endgroup$
    – J. W. Tanner
    Jan 13 at 17:02








4




4




$begingroup$
What is the cardinality of $mathbb{Q}?$ What is the cardinality of $mathbb{Q}^2?$
$endgroup$
– saulspatz
Jan 13 at 17:01




$begingroup$
What is the cardinality of $mathbb{Q}?$ What is the cardinality of $mathbb{Q}^2?$
$endgroup$
– saulspatz
Jan 13 at 17:01




2




2




$begingroup$
You could have two vector spaces of the same cardinality but different dimension so not isomorphic
$endgroup$
– J. W. Tanner
Jan 13 at 17:02




$begingroup$
You could have two vector spaces of the same cardinality but different dimension so not isomorphic
$endgroup$
– J. W. Tanner
Jan 13 at 17:02










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