We will extend Ostrowki’s theorem from Q to the quadratic field Q(i). On Q, every nonarchimedean absolute value is equivalent to the p-adic absolute value for a unique prime number p, and the archimedean absolute values are all equivalent to the usual absolute value on Q. We will see a similar thing happens in Q(i): any non-archimedean absolute value is associated to a prime in Z[i] (unique up ...

In the classical multivariate time series models the residuals are assumed to be normally distributed. However the assumption of normality is rarely consistent with the empirical evidence and leads to possibly incorrect inferences from financial models. The copula theory allows us to extend the classical time series models to nonelliptically distributed residuals. In this paper we analyze the t...

In this paper, we solve the additive ρ -functional inequalities ‖ f (x+ y)− f (x)− f (y)‖ ∥∥∥ρ ( 2 f ( x+ y 2 ) − f (x)− f (y) ∥∥∥ (0.1) and ∥∥∥2 f ( x+ y 2 ) − f (x)− f (y) ∥∥∥ ‖ρ ( f (x+ y)− f (x)− f (y))‖ , (0.2) where ρ is a fixed non-Archimedean number with |ρ| < 1 . Furthermore, we prove the Hyers-Ulam stability of the additive ρ -functional inequalities (0.1) and (0.2) in non-Archimedean...

There are compelling historical and mathematical reasons why we ended up, among others in Physics, with using the scalars given by the real numbers in R, or the complex numbers in C. Recently, however, infinitely many easy to construct and use other algebras of scalars have quite naturally emerged in a number of branches of Applied Mathematics. These algebras of scalars can deal with the long d...

We use a recent characterization of the d-dimensional Archimedean copulas as the survival copulas of d-dimensional simplex distributions (McNeil and Nešlehová (2009)) to construct new Archimedean copula families, and to examine the relationship between their dependence properties and the radial parts of the corresponding simplex distributions. In particular, a new formula for Kendall’s tau is d...

One of the features inherent in nested Archimedean copulas, also called hierarchical Archimedean copulas, is their rooted tree structure. In this paper, a nonparametric, rank-based method to estimate this structure is developed. Our approach consists in representing the rooted tree structure as a set of trivariate structures that can be estimated individually. Indeed, for any triple of variable...

Let G → GL(n,C) be a representation of a complex reductive group. A theorem of Hilbert says that the algebra C[x1, . . . , xn] of invariant polynomials is finitely generated. Let Y be the projective variety defined by this graded algebra, and then we have a rational morphism π : C · · · → Y(C). A theorem on geometric reductivity of Mumford says that a point x ∈ C is regular for the map π if and...

Abstract For every $m\in \mathbb {N}$ , we establish the equidistribution of sequence averaged pullbacks a Dirac measure at any given value in $\mathbb {C}\setminus \{0\}$ under $m$ th order derivatives iterates polynomials $f\in {C}[z]$ degree $d&gt;1$ towards harmonic filled-in Julia set f with pole $\infty $ . We also non-archimedean and arithmetic counterparts using potential theory on Berk...

Considerable progress in the synthesis of anisotropic patchy nanoplates (nanoplatelets) promises a rich variety of highly ordered two-dimensional superlattices. Recent experiments of superlattices assembled from nanoplates confirm the accessibility of exotic phases and motivate the need for a better understanding of the underlying self-assembly mechanisms. Here, we present experimentally access...