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In a paper which appeared a few years ago the authors investigated the exponential representation of functions analytic in the upper half-plane with positive imaginary part there [1]. We refer to that paper in the sequel as A-D. One of the principal results of A-D, there called Theorem A, can be extended to a considerably more general result, the proof of which is perhaps simpler than that given in A-D. We give the extended version of Theorem A here. We will use the notations and results of A-D without further explanations. Before we present the extension and its proof we would like to add some information that by oversight was omitted from the list of fundamental properties of the functions in the class P given in Section 1 of A-D. In such a comprehensive review one should mention that the classical theorem on representation of a positive harmonic function in a circle by a Poisson-Stieltjes integral is due to G. Herglotz [2]. The following results of L. H. Loomis [3] were not given: XVII. For all ~ for which /t[~] = O, the limits lira Im[~b(~ + iq)] ~l~ O and lira hOg(A) exist and are f ini te simultaneously and are equal. Their ~ 0 common value is the symmetric derivative of #(A) at 2 = ~ multiplied by ~r. XVIII. I f for two values of 0 in the interval 0 < 0 < ~

The paper ‘A Homological Foundation for Scale Problems in Physics’ (Atkin & Bastin, 1970) is criticised on account of several inconsistencies in the argument. Possible applications of the general ideas used are then discussed in the context of a ‘quantum logic’ type of framework.

The aim of this short note is to improve some recent results of B. Grunbaum by some remarks. We use Grunbaum's notations.

The dynamic response of an infinite, elastic plate to a steadily moving transverse force is studied under the so-called improved plate theory. Analytic solutions for the subsonic and the intersonic cases are obtained using the method of integral transforms. The usual difficulty of the nonuniqueness of the steady-state solutions is circumvented by formulating the problems as initial value problems and then seeking the large time limits of the solutions of such initial value problems. The subsonic and intersonic solutions obtained here are similar to that obtained previously for the supersonic case. However, in contrast with the supersonic solution, which contains two families of Mach lines, the subsonic solution contains no Mach lines and the intersonic solution contains only one family of Mach lines.

Results of A. Feldzamen on semi-similarity of operators are proved here using matrix methods. The use of these methods yields simpler proofs, the formulations of the theorems assume a more transparent form.

Two lower bounds of Sperb for the first eigenvalue of an elastically attached membrane are proved in an elementary way.

For every separable Banach spaceX there is a Banach spaceY with a separable dual such thatY ⊕X* ≈Y**. There is also a separable spaceZ so thatZ**/JZ is isomorphic toX.

Let H be a real or complex Hilbert space and let L p(1≦p

This is a short exposition and slight reorgnization of Hahn’s work concerning discrete real time flows with quasi-discrete spectra.

In sections 2 and 3 two methods for proving the non existence of certain universal Banach spaces, are presented. In section 4 it is proved that every infinite-dimensional conjugate Banach space has a two-dimensional subspace whose unit cell is not a polygon.

Within the class of offspring distributions with given meanm>1 and probability of no offspringp o, the probabilityq of ultimate extinction in a Galton-Watson branching process starting from one individual satisfiesp 0

B. R. Srinivasan has defined a weakly inverse semigroup in his paper "Weakly Inverse Semigroups" El], using the following terminology. An idempotent e in a semigroup S is called a principal idempotent of S if f e f = f e for all idempotents f in S. An element a in S is called a principal element of S if there exists an inverse a' of a such that aa' is a principal idempotent. Let Ea denote the set of principal inverses of the element a (the inverses of a which are principal elements of S). Then a semigroup S is called weakly inverse if for each element a in S, the set Ea is not null, and for an), elements a, b in S

In a recent paper on subreflexive normed linear spaces (see Arch. Math. 8, 444--450 (1957)) and its correction (see Arch. Math. 9,439--440, (1958)) R. R. PHELPS proved the following theorem.

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My proof of Kellogg's theorem for solutions of Plateau's problem (these Inventiones math. 8, 3 1 3 333 (1969)) can still be shortened: The relation ~p(e ia) ~'(x(eia))= 0 from p. 328 is available in almost all boundary points as soon as it is known that the functions fj(w) belong to class C o, l(p). The proof of this fact is accomplished on the bottom of p. 324. Let now w = 1 be the point described in the middle ofp. 325. From