The pioneeringwork of Markowitz (1952) formally established the intrinsic tradeoff between
risk and return. This paradigm provided the foundation upon which the modern theory of …

This paper calculates, in a precise way. the complexity of the index sets for three classes of
computable structures: the class of structures of Scott rank , the class , of structures of Scott …

We report the development of an optical system based on diffractive optical elements and
uniaxial crystals to produce radially and azimuthally polarized beams, including beams of …

We investigate effective categoricity of computable equivalence structures A. We show that
A is computably categorical if and only if A has only finitely many finite equivalence classes, …

We discuss using the cabling procedure to calculate colored HOMFLY polynomials. We
describe how it can be used and how the projectors and $\mathcal{R}$ -matrices needed for this …

We consider two kinds of reducibilities on finite families of predicates on a countable set: the
definability of predicates and their complements of one family via another by means of …

The relationship between ideals I of Turing degrees and groups of I-recursive automorphisms
of the ordering on rationals is studied. We discuss the differences between such groups …

We study linear orders definable over negative and positive equivalences and their computable
automorphisms. Special attention is paid to equivalences like η(α) = α 2 ∪id ω , α ⊆ ω. …

We investigate effective categoricity of computable Abelian p-groups A. We prove that all
computably categorical Abelian p-groups are relatively computably categorical, that is, have …

It is shown that the class of all possible families of Σ-subsets of finite ordinals in admissible
sets coincides with a class of all non-empty families closed under e-reducibility and ⊕. The …