$C_0$ direct sum of complex matrices











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How many elements in the $C_0$ direct sum of complex matrices,say$oplus_n M_n(mathbb{C})$? $oplus_n M_n(mathbb{C})={(x_n)in prod_n M_n(mathbb{C}):|x_n| to 0}$



I think there are uncountably many elements in $oplus_n M_n(mathbb{C})$,but one professor told me that it was not true.Why?










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  • What did you try so far ? What about $mathbb C$ itself ?
    – André S.
    yesterday












  • I think we can let the n-th elment be 1,others are 0,there are uncountably many elements.
    – mathrookie
    23 hours ago










  • I don't understand your approach. The collection of elements you describe is countable. Note that $mathbb C$ is uncountable already.
    – André S.
    22 hours ago












  • I do not understand the question. Any $C$-vector space is (at least) uncountable
    – Adrián González-Pérez
    21 hours ago










  • @André S.You mean $mathbb{C}$ in $oplus_{c_0}M_n(mathbb{C})$?
    – mathrookie
    19 hours ago

















up vote
-1
down vote

favorite












How many elements in the $C_0$ direct sum of complex matrices,say$oplus_n M_n(mathbb{C})$? $oplus_n M_n(mathbb{C})={(x_n)in prod_n M_n(mathbb{C}):|x_n| to 0}$



I think there are uncountably many elements in $oplus_n M_n(mathbb{C})$,but one professor told me that it was not true.Why?










share|cite|improve this question






















  • What did you try so far ? What about $mathbb C$ itself ?
    – André S.
    yesterday












  • I think we can let the n-th elment be 1,others are 0,there are uncountably many elements.
    – mathrookie
    23 hours ago










  • I don't understand your approach. The collection of elements you describe is countable. Note that $mathbb C$ is uncountable already.
    – André S.
    22 hours ago












  • I do not understand the question. Any $C$-vector space is (at least) uncountable
    – Adrián González-Pérez
    21 hours ago










  • @André S.You mean $mathbb{C}$ in $oplus_{c_0}M_n(mathbb{C})$?
    – mathrookie
    19 hours ago















up vote
-1
down vote

favorite









up vote
-1
down vote

favorite











How many elements in the $C_0$ direct sum of complex matrices,say$oplus_n M_n(mathbb{C})$? $oplus_n M_n(mathbb{C})={(x_n)in prod_n M_n(mathbb{C}):|x_n| to 0}$



I think there are uncountably many elements in $oplus_n M_n(mathbb{C})$,but one professor told me that it was not true.Why?










share|cite|improve this question













How many elements in the $C_0$ direct sum of complex matrices,say$oplus_n M_n(mathbb{C})$? $oplus_n M_n(mathbb{C})={(x_n)in prod_n M_n(mathbb{C}):|x_n| to 0}$



I think there are uncountably many elements in $oplus_n M_n(mathbb{C})$,but one professor told me that it was not true.Why?







operator-theory operator-algebras c-star-algebras von-neumann-algebras






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share|cite|improve this question











share|cite|improve this question




share|cite|improve this question










asked yesterday









mathrookie

649412




649412












  • What did you try so far ? What about $mathbb C$ itself ?
    – André S.
    yesterday












  • I think we can let the n-th elment be 1,others are 0,there are uncountably many elements.
    – mathrookie
    23 hours ago










  • I don't understand your approach. The collection of elements you describe is countable. Note that $mathbb C$ is uncountable already.
    – André S.
    22 hours ago












  • I do not understand the question. Any $C$-vector space is (at least) uncountable
    – Adrián González-Pérez
    21 hours ago










  • @André S.You mean $mathbb{C}$ in $oplus_{c_0}M_n(mathbb{C})$?
    – mathrookie
    19 hours ago




















  • What did you try so far ? What about $mathbb C$ itself ?
    – André S.
    yesterday












  • I think we can let the n-th elment be 1,others are 0,there are uncountably many elements.
    – mathrookie
    23 hours ago










  • I don't understand your approach. The collection of elements you describe is countable. Note that $mathbb C$ is uncountable already.
    – André S.
    22 hours ago












  • I do not understand the question. Any $C$-vector space is (at least) uncountable
    – Adrián González-Pérez
    21 hours ago










  • @André S.You mean $mathbb{C}$ in $oplus_{c_0}M_n(mathbb{C})$?
    – mathrookie
    19 hours ago


















What did you try so far ? What about $mathbb C$ itself ?
– André S.
yesterday






What did you try so far ? What about $mathbb C$ itself ?
– André S.
yesterday














I think we can let the n-th elment be 1,others are 0,there are uncountably many elements.
– mathrookie
23 hours ago




I think we can let the n-th elment be 1,others are 0,there are uncountably many elements.
– mathrookie
23 hours ago












I don't understand your approach. The collection of elements you describe is countable. Note that $mathbb C$ is uncountable already.
– André S.
22 hours ago






I don't understand your approach. The collection of elements you describe is countable. Note that $mathbb C$ is uncountable already.
– André S.
22 hours ago














I do not understand the question. Any $C$-vector space is (at least) uncountable
– Adrián González-Pérez
21 hours ago




I do not understand the question. Any $C$-vector space is (at least) uncountable
– Adrián González-Pérez
21 hours ago












@André S.You mean $mathbb{C}$ in $oplus_{c_0}M_n(mathbb{C})$?
– mathrookie
19 hours ago






@André S.You mean $mathbb{C}$ in $oplus_{c_0}M_n(mathbb{C})$?
– mathrookie
19 hours ago

















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