- #1
Euge
Gold Member
MHB
POTW Director
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Here is this week's POTW:
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Show that if $(X,\mathcal{M},\mu)$, $(Y,\mathcal{N},\nu)$ are finite measure spaces, $1 < p < \infty$, and $K$ is a measurable function on $X\times Y$, there is a bounded integral operator $I(K) : \mathscr{L}^p(\nu) \to \mathscr{L}^p(\mu)$ given by
$$I(K)(f) :x \mapsto \int_Y K(x,y)\,f(y)\, d\nu(y)\quad (f\in \mathscr{L}^p(\mu)),$$
provided that the kernel $K$ satisfies the conditions $\sup_x \int_Y \lvert K(x,y)\rvert\, d\nu(y) < \infty$ and $\sup_y \int_X \lvert K(x,y)\rvert \, d\mu(x) < \infty$.
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Remember to read the http://www.mathhelpboards.com/showthread.php?772-Problem-of-the-Week-%28POTW%29-Procedure-and-Guidelines to find out how to http://www.mathhelpboards.com/forms.php?do=form&fid=2!
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Show that if $(X,\mathcal{M},\mu)$, $(Y,\mathcal{N},\nu)$ are finite measure spaces, $1 < p < \infty$, and $K$ is a measurable function on $X\times Y$, there is a bounded integral operator $I(K) : \mathscr{L}^p(\nu) \to \mathscr{L}^p(\mu)$ given by
$$I(K)(f) :x \mapsto \int_Y K(x,y)\,f(y)\, d\nu(y)\quad (f\in \mathscr{L}^p(\mu)),$$
provided that the kernel $K$ satisfies the conditions $\sup_x \int_Y \lvert K(x,y)\rvert\, d\nu(y) < \infty$ and $\sup_y \int_X \lvert K(x,y)\rvert \, d\mu(x) < \infty$.
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Remember to read the http://www.mathhelpboards.com/showthread.php?772-Problem-of-the-Week-%28POTW%29-Procedure-and-Guidelines to find out how to http://www.mathhelpboards.com/forms.php?do=form&fid=2!