Banach algebra $l^p$ is not isomorphic to $C^{*}$ algebra
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Consider commutative Banach algebra $l^p$, $p in [1,infty)$ with multiplication by coordinates. I know, that $Delta (l^{p})={e_n : n in mathbb{N}}$ - set of canonical functionals. We know that $widehat{x}(e_n)=x_n$ and $widehat{x}: l^{p} to C_0(Delta (l^{p}))$. Because there exists $xin l^{p}$ such that $x_ineq x_j$ for $ineq j$, and Gelfand transformation is continuous, GT must be discrete. I would like to show, that GT is or is not surjective, but I do not have any idea. Many thanks
abstract-algebra lp-spaces group-isomorphism banach-algebras gelfand-representation
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Consider commutative Banach algebra $l^p$, $p in [1,infty)$ with multiplication by coordinates. I know, that $Delta (l^{p})={e_n : n in mathbb{N}}$ - set of canonical functionals. We know that $widehat{x}(e_n)=x_n$ and $widehat{x}: l^{p} to C_0(Delta (l^{p}))$. Because there exists $xin l^{p}$ such that $x_ineq x_j$ for $ineq j$, and Gelfand transformation is continuous, GT must be discrete. I would like to show, that GT is or is not surjective, but I do not have any idea. Many thanks
abstract-algebra lp-spaces group-isomorphism banach-algebras gelfand-representation
$endgroup$
add a comment |
$begingroup$
Consider commutative Banach algebra $l^p$, $p in [1,infty)$ with multiplication by coordinates. I know, that $Delta (l^{p})={e_n : n in mathbb{N}}$ - set of canonical functionals. We know that $widehat{x}(e_n)=x_n$ and $widehat{x}: l^{p} to C_0(Delta (l^{p}))$. Because there exists $xin l^{p}$ such that $x_ineq x_j$ for $ineq j$, and Gelfand transformation is continuous, GT must be discrete. I would like to show, that GT is or is not surjective, but I do not have any idea. Many thanks
abstract-algebra lp-spaces group-isomorphism banach-algebras gelfand-representation
$endgroup$
Consider commutative Banach algebra $l^p$, $p in [1,infty)$ with multiplication by coordinates. I know, that $Delta (l^{p})={e_n : n in mathbb{N}}$ - set of canonical functionals. We know that $widehat{x}(e_n)=x_n$ and $widehat{x}: l^{p} to C_0(Delta (l^{p}))$. Because there exists $xin l^{p}$ such that $x_ineq x_j$ for $ineq j$, and Gelfand transformation is continuous, GT must be discrete. I would like to show, that GT is or is not surjective, but I do not have any idea. Many thanks
abstract-algebra lp-spaces group-isomorphism banach-algebras gelfand-representation
abstract-algebra lp-spaces group-isomorphism banach-algebras gelfand-representation
edited Jan 7 at 23:16
Martin Sleziak
44.7k9117272
44.7k9117272
asked Jan 7 at 16:25
LeoLeeLeoLee
112
112
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