Kernel of linear operator with functions having Fourier transform supported in $[0,infty)$

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A bounded linear operator $ T: L^2 to L^2$ with this properties :
1. Commutes with translation
2. Commutes with dilation
3. Has in its kernel functions $ f $ such that support $hat f subseteq [0,infty) $



I already can prove that $T= f* mu$ where $mu $ is a tempered distribution.



Then $int_-infty^0hat f(s)e^2ipi s x ds =c Tf (x)$ where $ c $ is s constant. How to prove this ?







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A bounded linear operator $ T: L^2 to L^2$ with this properties :
1. Commutes with translation
2. Commutes with dilation
3. Has in its kernel functions $ f $ such that support $hat f subseteq [0,infty) $



I already can prove that $T= f* mu$ where $mu $ is a tempered distribution.



Then $int_-infty^0hat f(s)e^2ipi s x ds =c Tf (x)$ where $ c $ is s constant. How to prove this ?







share|cite|improve this question






















  • Welcome to MSE. Please read this text about how to ask a good question.
    – José Carlos Santos
    Aug 26 at 7:59












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down vote

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A bounded linear operator $ T: L^2 to L^2$ with this properties :
1. Commutes with translation
2. Commutes with dilation
3. Has in its kernel functions $ f $ such that support $hat f subseteq [0,infty) $



I already can prove that $T= f* mu$ where $mu $ is a tempered distribution.



Then $int_-infty^0hat f(s)e^2ipi s x ds =c Tf (x)$ where $ c $ is s constant. How to prove this ?







share|cite|improve this question














A bounded linear operator $ T: L^2 to L^2$ with this properties :
1. Commutes with translation
2. Commutes with dilation
3. Has in its kernel functions $ f $ such that support $hat f subseteq [0,infty) $



I already can prove that $T= f* mu$ where $mu $ is a tempered distribution.



Then $int_-infty^0hat f(s)e^2ipi s x ds =c Tf (x)$ where $ c $ is s constant. How to prove this ?









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edited Aug 26 at 9:19









Bernard

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asked Aug 26 at 7:53







user586523


















  • Welcome to MSE. Please read this text about how to ask a good question.
    – José Carlos Santos
    Aug 26 at 7:59
















  • Welcome to MSE. Please read this text about how to ask a good question.
    – José Carlos Santos
    Aug 26 at 7:59















Welcome to MSE. Please read this text about how to ask a good question.
– José Carlos Santos
Aug 26 at 7:59




Welcome to MSE. Please read this text about how to ask a good question.
– José Carlos Santos
Aug 26 at 7:59










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Take the fourier transform of $Tf=f*mu$



$hatTf=m(s)hatf$ where $m(s)$ is the fourier transform of $mu$



So $m(s)$ must be zero on the positive real line and non zero on the negative real line. Combining this with the dilation property implies the result you asked.






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    Take the fourier transform of $Tf=f*mu$



    $hatTf=m(s)hatf$ where $m(s)$ is the fourier transform of $mu$



    So $m(s)$ must be zero on the positive real line and non zero on the negative real line. Combining this with the dilation property implies the result you asked.






    share|cite|improve this answer
























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      down vote













      Take the fourier transform of $Tf=f*mu$



      $hatTf=m(s)hatf$ where $m(s)$ is the fourier transform of $mu$



      So $m(s)$ must be zero on the positive real line and non zero on the negative real line. Combining this with the dilation property implies the result you asked.






      share|cite|improve this answer






















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        up vote
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        down vote









        Take the fourier transform of $Tf=f*mu$



        $hatTf=m(s)hatf$ where $m(s)$ is the fourier transform of $mu$



        So $m(s)$ must be zero on the positive real line and non zero on the negative real line. Combining this with the dilation property implies the result you asked.






        share|cite|improve this answer












        Take the fourier transform of $Tf=f*mu$



        $hatTf=m(s)hatf$ where $m(s)$ is the fourier transform of $mu$



        So $m(s)$ must be zero on the positive real line and non zero on the negative real line. Combining this with the dilation property implies the result you asked.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Aug 26 at 9:50







        user587275


































             

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