A Menger algebra of 2-place functions over a set Δ is (cf. [5]) a set 6 of functions mapping Δ x Δ into Δ, which is closed with respect to substitution or composition, i.e., has the property that, for any three functions F, G, H belonging to 6, the composite function F{G,H) belongs to 6. Here, F{G,H) is the function assuming the value F(G(x,y), H(x9y)) for each (x,y) in Δ x Δ. The purpose of th...

With the publication of Murray N. Rothbard’s monumental work An Austrian Perspective on the History of Economic Thought in 1995, contemporary Austrian economists have become aware that they are the modern heirs to a grand intellectual tradition. The first fruit of further research in the Austrian tradition was 15 Great Austrian Economists, a small volume edited by Randall G. Holcombe in 1999. I...

We discuss 1-Ahlfors-regular connected sets in a metric space. We prove that such a set is ‘flat’ on most scales and locations. We give a quantitative version of this. This, together with work of I. Hahlomaa, gives a characterization of 1-Ahlfors regular subsets of 1-Ahlfors-regular curves in a metric space, generalizing in a way the Analyst’s (Geometric) Traveling Salesman theorems by P. Jones...

Using a portion of the Continuum Hypothesis, we prove that there is a Menger-bounded (also called o-bounded) subgroup of the Baire group Z, whose square is not Menger-bounded. This settles a major open problem concerning boundedness notions for groups, and implies that Menger-bounded groups need not be Scheepers-bounded.

We study subgroups of Z which possess group theoretic properties analogous to properties introduced by Menger (1924), Hurewicz (1925), Rothberger (1938), and Scheepers (1996). We obtain purely combinatorial characterizations of these properties, and combine them with other techniques to solve several questions of Babinkostova, Kočinac, and Scheepers. We also show that, while the Menger Conjectu...

We study subgroups of Z which possess group theoretic properties analogous to properties introduced by Menger (1924), Hurewicz (1925), Rothberger (1938), and Scheepers (1996). The studied properties were introduced independently by Kočinac and Okunev. We obtain purely combinatorial characterizations of these properties, and combine them with other techniques to solve several questions of Babink...

The main goal of this paper is to present an alternative, real variable proof of the T(1)-Theorem for the Cauchy Integral. We then prove that the estimate from below of analytic capacity in terms of total Menger curvature is a direct consequence of the T(1)-Theorem. An example shows that the L 1-BMO estimate for the Cauchy Integral does not follow from L 2 boundedness when the underlying measur...