Weakly compactly generated Frechet spaces.
Let 𝕋 denote the set of complex numbers of modulus 1. Let v ∈ 𝕋, v not a root of unity, and let T: 𝕋 → 𝕋 be the transformation on 𝕋 given by T(z) = vz. It is known that the problem of calculating the outer measure of a T-invariant set leads to a condition which formally has a close resemblance to Carathéodory's definition of a measurable set. In ergodic theory terms, T is not weakly mixing. Now there is an example, due to Kakutani, of a transformation ψ̃ which is weakly mixing but not strongly...
I discuss the properties of α-favourable and weakly α-favourable measure spaces, with remarks on their relations with other classes.
We consider the set of complex-valued homomorphisms of a uniform algebra which are weak-star continuous with respect to a fixed measure . The -parts of are defined, and a decomposition theorem for measures in is obtained, in which constituent summands are mutually absolutely continuous with respect to representing measures. The set is studied for -invariant algebras on compact subsets of the complex plane and also for the infinite polydisc algebra.
In this note, we prove that the countable compactness of together with the Countable Axiom of Choice yields the existence of a nonmeasurable subset of . This is done by providing a family of nonmeasurable subsets of whose intersection with every non-negligible Lebesgue measurable set is still not Lebesgue measurable. We develop this note in three sections: the first presents the main result, the second recalls known results concerning non-Lebesgue measurability and its relations with the Axiom...
We discuss the problem when ℵ₁ sets are contained in a σ-generated σ-field on some set X. This is related to a problem raised by K. P. S. Bhaskara Rao and Rae Michael Shortt [Dissertationes Math. 372 (1998)] which we answer. We also briefly discuss generating the family of all subsets from rectangles.
We study the problem in the title and show that it is equivalent to the fact that every set of reals is an increasing union of measurable sets. We also show the relationship of it with Sierpi'nski sets.
Suppose is closed. Is it true that the typical (in the sense of Baire category) function in is one-to-one on ? If we show that the answer to this question is yes, though we construct an with for which the answer is no. If is the middle- Cantor set we prove that the answer is yes if and only if There are ’s with Hausdorff dimension one for which the answer is still yes. Some other related results are also presented.