convex cone in complex Banach space











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A convex cone is defined as (by Wikipedia):
A convex cone is a subset of a vector space over an ordered field that is closed under linear combinations with positive coefficients.



In my research work, I need a convex cone in a complex Banach space, but the set of complex numbers is not an ordered field. Then how to define a convex cone in a complex Banach space? I tried to define such a partial order on $mathbb C$ so that it can be a total order on $mathbb C$ but I could not succeed.










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    Convex cones are defined the same for complex Banach spaces as they are defined for real Banach spaces.
    – Kavi Rama Murthy
    Nov 22 at 9:34

















up vote
0
down vote

favorite












A convex cone is defined as (by Wikipedia):
A convex cone is a subset of a vector space over an ordered field that is closed under linear combinations with positive coefficients.



In my research work, I need a convex cone in a complex Banach space, but the set of complex numbers is not an ordered field. Then how to define a convex cone in a complex Banach space? I tried to define such a partial order on $mathbb C$ so that it can be a total order on $mathbb C$ but I could not succeed.










share|cite|improve this question


















  • 1




    Convex cones are defined the same for complex Banach spaces as they are defined for real Banach spaces.
    – Kavi Rama Murthy
    Nov 22 at 9:34















up vote
0
down vote

favorite









up vote
0
down vote

favorite











A convex cone is defined as (by Wikipedia):
A convex cone is a subset of a vector space over an ordered field that is closed under linear combinations with positive coefficients.



In my research work, I need a convex cone in a complex Banach space, but the set of complex numbers is not an ordered field. Then how to define a convex cone in a complex Banach space? I tried to define such a partial order on $mathbb C$ so that it can be a total order on $mathbb C$ but I could not succeed.










share|cite|improve this question













A convex cone is defined as (by Wikipedia):
A convex cone is a subset of a vector space over an ordered field that is closed under linear combinations with positive coefficients.



In my research work, I need a convex cone in a complex Banach space, but the set of complex numbers is not an ordered field. Then how to define a convex cone in a complex Banach space? I tried to define such a partial order on $mathbb C$ so that it can be a total order on $mathbb C$ but I could not succeed.







functional-analysis banach-spaces normed-spaces






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asked Nov 22 at 9:32









Infinity

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545313








  • 1




    Convex cones are defined the same for complex Banach spaces as they are defined for real Banach spaces.
    – Kavi Rama Murthy
    Nov 22 at 9:34
















  • 1




    Convex cones are defined the same for complex Banach spaces as they are defined for real Banach spaces.
    – Kavi Rama Murthy
    Nov 22 at 9:34










1




1




Convex cones are defined the same for complex Banach spaces as they are defined for real Banach spaces.
– Kavi Rama Murthy
Nov 22 at 9:34






Convex cones are defined the same for complex Banach spaces as they are defined for real Banach spaces.
– Kavi Rama Murthy
Nov 22 at 9:34












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If $X$ is a complex Banach space and $C subseteq X$, then $C$ is called a convex cone if $x,y in C $ and $s,t in [0, infty)$ imply that $sx+ty in C$.






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    up vote
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    accepted










    If $X$ is a complex Banach space and $C subseteq X$, then $C$ is called a convex cone if $x,y in C $ and $s,t in [0, infty)$ imply that $sx+ty in C$.






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      up vote
      0
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      accepted










      If $X$ is a complex Banach space and $C subseteq X$, then $C$ is called a convex cone if $x,y in C $ and $s,t in [0, infty)$ imply that $sx+ty in C$.






      share|cite|improve this answer























        up vote
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        accepted







        up vote
        0
        down vote



        accepted






        If $X$ is a complex Banach space and $C subseteq X$, then $C$ is called a convex cone if $x,y in C $ and $s,t in [0, infty)$ imply that $sx+ty in C$.






        share|cite|improve this answer












        If $X$ is a complex Banach space and $C subseteq X$, then $C$ is called a convex cone if $x,y in C $ and $s,t in [0, infty)$ imply that $sx+ty in C$.







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        answered Nov 22 at 9:59









        Fred

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