Abstract. Let S be the Hubert space of entire functions f(z) such that ||/(z)||2 = JJ" \f(z)\2 dm(z), where zzz is a positive measure defined on the Borel sets of the complex plane. Two Hubert spaces are constructed in which polynomials are not dense. In the second example, our space is one which contains all exponentials and yet in which the exponentials are not complete. This is a somewhat su...

In [4] the author set forth a complete set of unitary invariants for a certain class of operators on Hubert space. The operators considered were exactly those operators which generate a finite W*algebra of type I in the terminology of [2]. One immediately wants to know some nontrivial examples of such operators, and Brown provided several examples in [l]. (Nontrivial here means non-normal opera...

The main result is that any continuous real-linear operator A on a quaternionic Hubert space has a unique decomposition A=A0+iiAl + izAi+iiA3, where the A„ are continuous linear operators and (fi,f2,'3) is any right-handed orthonormal triad of vector quaternions. Other results concern the place of the colinear and complex-linear operators in this characterisation and the effect on the Av of a r...

A great master of mathematics passed away when David Hubert died in Göttingen on February the 14th, 1943, at the age of eightyone. In retrospect it seems to us that the era of mathematics upon which he impressed the seal of his spirit and which is now sinking below the horizon achieved a more perfect balance than prevailed before and after, between the mastering of single concrete problems and ...

Christhard Schrenk und Hubert Weckbach, Die Vergangenheit für die Zukunft bewahren: Das Stadtarchiv Heilbronn (Veröffentlichungen des Archivs der Stadt Heilbronn, Bd. 33), (Stadtarchiv Heilbronn) 1993. 192 S.

The question of obtaining more precise information about the term o(l) in (3) seems to have been first publicly raised by W. W. Sawyer [ l ] . Because of the interest of this problem in numerical analysis [2] it has been investigated by several workers [3; 4; 5] with the result that various upper and lower bounds for the rate of growth of this term are known. We have been able to determine the ...