We characterize all subsets $M$ of $\Bbb R^n \times \Bbb R^+$ such that $$ \sup\limits_{X\in \Bbb R^n \times \Bbb R^+}u(X) = \sup\limits_{X\in M}u(X) $$ for every bounded parabolic function $u$ on $\Bbb R^n \times \Bbb R^+$. The closely related problem of representing functions as sums of Weierstrass kernels corresponding to points of $M$ is also considered. The results provide a parabolic counterpart to results for classical harmonic functions in a ball, see References. As a by-product the question of representability of probability continuous distributions as sums of multiples of normal distributions is investigated.
@article{118689, author = {Jarmila Rano\v sov\'a}, title = {Sets of determination for parabolic functions on a half-space}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {35}, year = {1994}, pages = {497-513}, zbl = {0808.35043}, mrnumber = {1307276}, language = {en}, url = {http://dml.mathdoc.fr/item/118689} }
Ranošová, Jarmila. Sets of determination for parabolic functions on a half-space. Commentationes Mathematicae Universitatis Carolinae, Tome 35 (1994) pp. 497-513. http://gdmltest.u-ga.fr/item/118689/
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