What is the relation between $lVert{Hp}rVert^2$ and $lVert{H}rVert$ when $Hpne0$ and $lVert{p}rVert = 1$?
$begingroup$
What is the relation between $lVert{Hp}rVert^2$ and $lVert{H}rVert$ when $Hpne0$ and $lVert{p}rVert = 1$?
Note that $H$ and $p$ are sampled value of Gaussian distributed random variables, in which $H$ is a vector with a size of $1$ by $N$ and $p$ is a vector with a size of $N$ by $1$?
I think $$lVert{Hp}rVert^2 = lVert{H}rVert.$$
However, I failed to prove the above equation.
Is my thought wrong?
Thanks for reading my question.
vectors
$endgroup$
add a comment |
$begingroup$
What is the relation between $lVert{Hp}rVert^2$ and $lVert{H}rVert$ when $Hpne0$ and $lVert{p}rVert = 1$?
Note that $H$ and $p$ are sampled value of Gaussian distributed random variables, in which $H$ is a vector with a size of $1$ by $N$ and $p$ is a vector with a size of $N$ by $1$?
I think $$lVert{Hp}rVert^2 = lVert{H}rVert.$$
However, I failed to prove the above equation.
Is my thought wrong?
Thanks for reading my question.
vectors
$endgroup$
add a comment |
$begingroup$
What is the relation between $lVert{Hp}rVert^2$ and $lVert{H}rVert$ when $Hpne0$ and $lVert{p}rVert = 1$?
Note that $H$ and $p$ are sampled value of Gaussian distributed random variables, in which $H$ is a vector with a size of $1$ by $N$ and $p$ is a vector with a size of $N$ by $1$?
I think $$lVert{Hp}rVert^2 = lVert{H}rVert.$$
However, I failed to prove the above equation.
Is my thought wrong?
Thanks for reading my question.
vectors
$endgroup$
What is the relation between $lVert{Hp}rVert^2$ and $lVert{H}rVert$ when $Hpne0$ and $lVert{p}rVert = 1$?
Note that $H$ and $p$ are sampled value of Gaussian distributed random variables, in which $H$ is a vector with a size of $1$ by $N$ and $p$ is a vector with a size of $N$ by $1$?
I think $$lVert{Hp}rVert^2 = lVert{H}rVert.$$
However, I failed to prove the above equation.
Is my thought wrong?
Thanks for reading my question.
vectors
vectors
asked Jan 27 at 14:28
Danny_KimDanny_Kim
1,3911624
1,3911624
add a comment |
add a comment |
1 Answer
1
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$begingroup$
All you can state is
$$|Hp|^2 le |H|^2$$
Can you prove this one?
$endgroup$
$begingroup$
Actually, I tried many times using MATLAB program. I could observe that the value of RHS is much larger than that of LHS.
$endgroup$
– Danny_Kim
Jan 27 at 14:46
$begingroup$
Well, by compactness of the unit sphere, there exists a unit vector $p$ such that $|Hp|=|H|$..
$endgroup$
– Berci
Jan 27 at 14:52
$begingroup$
However, to prove $lVert HprVert^2 le lVert HrVert^2$, do we have to prove that there do not exist $p$ such that $lVert HprVert^2 ge lVert HrVert^2$? Intuitively, each element of $p$ must be less than $1$, so each element of $Hp$ MAY be less than or equal to that of $H$. Is it enough to prove the above equation? I am not sure that it is enough.
$endgroup$
– Danny_Kim
Jan 27 at 14:55
add a comment |
Your Answer
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
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active
oldest
votes
active
oldest
votes
$begingroup$
All you can state is
$$|Hp|^2 le |H|^2$$
Can you prove this one?
$endgroup$
$begingroup$
Actually, I tried many times using MATLAB program. I could observe that the value of RHS is much larger than that of LHS.
$endgroup$
– Danny_Kim
Jan 27 at 14:46
$begingroup$
Well, by compactness of the unit sphere, there exists a unit vector $p$ such that $|Hp|=|H|$..
$endgroup$
– Berci
Jan 27 at 14:52
$begingroup$
However, to prove $lVert HprVert^2 le lVert HrVert^2$, do we have to prove that there do not exist $p$ such that $lVert HprVert^2 ge lVert HrVert^2$? Intuitively, each element of $p$ must be less than $1$, so each element of $Hp$ MAY be less than or equal to that of $H$. Is it enough to prove the above equation? I am not sure that it is enough.
$endgroup$
– Danny_Kim
Jan 27 at 14:55
add a comment |
$begingroup$
All you can state is
$$|Hp|^2 le |H|^2$$
Can you prove this one?
$endgroup$
$begingroup$
Actually, I tried many times using MATLAB program. I could observe that the value of RHS is much larger than that of LHS.
$endgroup$
– Danny_Kim
Jan 27 at 14:46
$begingroup$
Well, by compactness of the unit sphere, there exists a unit vector $p$ such that $|Hp|=|H|$..
$endgroup$
– Berci
Jan 27 at 14:52
$begingroup$
However, to prove $lVert HprVert^2 le lVert HrVert^2$, do we have to prove that there do not exist $p$ such that $lVert HprVert^2 ge lVert HrVert^2$? Intuitively, each element of $p$ must be less than $1$, so each element of $Hp$ MAY be less than or equal to that of $H$. Is it enough to prove the above equation? I am not sure that it is enough.
$endgroup$
– Danny_Kim
Jan 27 at 14:55
add a comment |
$begingroup$
All you can state is
$$|Hp|^2 le |H|^2$$
Can you prove this one?
$endgroup$
All you can state is
$$|Hp|^2 le |H|^2$$
Can you prove this one?
answered Jan 27 at 14:40


BerciBerci
61.7k23674
61.7k23674
$begingroup$
Actually, I tried many times using MATLAB program. I could observe that the value of RHS is much larger than that of LHS.
$endgroup$
– Danny_Kim
Jan 27 at 14:46
$begingroup$
Well, by compactness of the unit sphere, there exists a unit vector $p$ such that $|Hp|=|H|$..
$endgroup$
– Berci
Jan 27 at 14:52
$begingroup$
However, to prove $lVert HprVert^2 le lVert HrVert^2$, do we have to prove that there do not exist $p$ such that $lVert HprVert^2 ge lVert HrVert^2$? Intuitively, each element of $p$ must be less than $1$, so each element of $Hp$ MAY be less than or equal to that of $H$. Is it enough to prove the above equation? I am not sure that it is enough.
$endgroup$
– Danny_Kim
Jan 27 at 14:55
add a comment |
$begingroup$
Actually, I tried many times using MATLAB program. I could observe that the value of RHS is much larger than that of LHS.
$endgroup$
– Danny_Kim
Jan 27 at 14:46
$begingroup$
Well, by compactness of the unit sphere, there exists a unit vector $p$ such that $|Hp|=|H|$..
$endgroup$
– Berci
Jan 27 at 14:52
$begingroup$
However, to prove $lVert HprVert^2 le lVert HrVert^2$, do we have to prove that there do not exist $p$ such that $lVert HprVert^2 ge lVert HrVert^2$? Intuitively, each element of $p$ must be less than $1$, so each element of $Hp$ MAY be less than or equal to that of $H$. Is it enough to prove the above equation? I am not sure that it is enough.
$endgroup$
– Danny_Kim
Jan 27 at 14:55
$begingroup$
Actually, I tried many times using MATLAB program. I could observe that the value of RHS is much larger than that of LHS.
$endgroup$
– Danny_Kim
Jan 27 at 14:46
$begingroup$
Actually, I tried many times using MATLAB program. I could observe that the value of RHS is much larger than that of LHS.
$endgroup$
– Danny_Kim
Jan 27 at 14:46
$begingroup$
Well, by compactness of the unit sphere, there exists a unit vector $p$ such that $|Hp|=|H|$..
$endgroup$
– Berci
Jan 27 at 14:52
$begingroup$
Well, by compactness of the unit sphere, there exists a unit vector $p$ such that $|Hp|=|H|$..
$endgroup$
– Berci
Jan 27 at 14:52
$begingroup$
However, to prove $lVert HprVert^2 le lVert HrVert^2$, do we have to prove that there do not exist $p$ such that $lVert HprVert^2 ge lVert HrVert^2$? Intuitively, each element of $p$ must be less than $1$, so each element of $Hp$ MAY be less than or equal to that of $H$. Is it enough to prove the above equation? I am not sure that it is enough.
$endgroup$
– Danny_Kim
Jan 27 at 14:55
$begingroup$
However, to prove $lVert HprVert^2 le lVert HrVert^2$, do we have to prove that there do not exist $p$ such that $lVert HprVert^2 ge lVert HrVert^2$? Intuitively, each element of $p$ must be less than $1$, so each element of $Hp$ MAY be less than or equal to that of $H$. Is it enough to prove the above equation? I am not sure that it is enough.
$endgroup$
– Danny_Kim
Jan 27 at 14:55
add a comment |
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