finite dimensional $C^*$ subalgebra












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Given any $C^*$-algebra $A$ (not necessarily unital),can we construct a nonzero finite dimensional $C^*$-subalgebra of $A$?










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    Given any $C^*$-algebra $A$ (not necessarily unital),can we construct a nonzero finite dimensional $C^*$-subalgebra of $A$?










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      Given any $C^*$-algebra $A$ (not necessarily unital),can we construct a nonzero finite dimensional $C^*$-subalgebra of $A$?










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      Given any $C^*$-algebra $A$ (not necessarily unital),can we construct a nonzero finite dimensional $C^*$-subalgebra of $A$?







      operator-theory operator-algebras c-star-algebras






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      asked Dec 31 '18 at 18:38









      mathrookiemathrookie

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          No. Every finite dimensional $C^*$-algebra is a von Neumann algebra, because it is a Banach dual space. $W^*$ algebras contain many projections -- in particular the range projections of their elements -- but there are $C^*$-algebras with no projections.






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            $begingroup$

            No. Every finite dimensional $C^*$-algebra is a von Neumann algebra, because it is a Banach dual space. $W^*$ algebras contain many projections -- in particular the range projections of their elements -- but there are $C^*$-algebras with no projections.






            share|cite|improve this answer









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              2












              $begingroup$

              No. Every finite dimensional $C^*$-algebra is a von Neumann algebra, because it is a Banach dual space. $W^*$ algebras contain many projections -- in particular the range projections of their elements -- but there are $C^*$-algebras with no projections.






              share|cite|improve this answer









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                $begingroup$

                No. Every finite dimensional $C^*$-algebra is a von Neumann algebra, because it is a Banach dual space. $W^*$ algebras contain many projections -- in particular the range projections of their elements -- but there are $C^*$-algebras with no projections.






                share|cite|improve this answer









                $endgroup$



                No. Every finite dimensional $C^*$-algebra is a von Neumann algebra, because it is a Banach dual space. $W^*$ algebras contain many projections -- in particular the range projections of their elements -- but there are $C^*$-algebras with no projections.







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                answered Dec 31 '18 at 21:02









                Ashwin TrisalAshwin Trisal

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