In this paper we calculate the corrections to ztt̄ couplings induced by non-commuting ETC interactions. The extra parameters δg L, s 2 and 1 x of non-commuting ETC models and the usual SM parameters will be be assumed to be determined from a global fit to the LEP 1 EW data. We find that in the heavy (light) case F t L is modified by at most 4% (2.8%) relative to its SM value provided δRb < .0088...

It is shown that the full unknown state of a spin1 2 system, S, which, within Born’s statistical interpretation, is meant as the state of an ensemble of identically prepared systems and is described by its density matrix, can be determined with a simultaneous measurement with the help of an “assistant” system A whose initial state is known. The idea is to let S and A interact with each other in...

Given a square matrix with elements in the group-ring of a group, one can consider the sequence formed by the trace (in the sense of the group-ring) of its powers. We prove that the corresponding generating series is an algebraic G-function (in the sense of Siegel) when the group is free of finite rank. Consequently, it follows that the norm of such elements is an exactly computable algebraic n...

The focus of the present work was on the association between commuting (business and private), life satisfaction, stress, and (over-) use of the Internet. Considering that digital devices are omnipresent in buses and trains, no study has yet investigated if commuting contributes to the development of Internet addiction. Overall, N = 5039 participants (N = 3477 females, age M = 26.79, SD = 10.68...

Several arguments have been proposed some years ago, attempting to prove the impossibility of defining Lorentz-invariant elements of reality. I find that a sufficient condition for the existence of elements of reality, introduced in these proofs, is in fact also used as a necessary condition. I argue that Lorentz-invariant elements of reality can be defined but, as Vaidman pointed out, they won...

Vaught’s Conjecture states that if Σ is a complete first order theory in a countable language such that Σ has uncountably many pairwise non-isomorphic countably infinite models, then Σ has 2א0 many pairwise non-isomorphic countably infinite models. Continuing investigations initiated in [17], we apply methods of algebraic logic to study some variants of Vaught’s conjecture. More concretely, let...

Let f : (a, b)R. The function f is said to be matrix monotone if A ≤ B implies f(A) ≤ f(B) for all pairs of likesized self-adjoint matrices with spectrum in (a, b). Classically, Charles Loewner showed that a bounded Borel function is matrix monotone if and only if it is analytic and extends to be a self-map of the upper half plane. The theory of matrix montonicity has profound consequences for ...

Given a finite group G, we consider the problem of finding the maximal size nc(G) of subsets of G that have the property that no two of their elements of commute. After constructing a large noncommuting subset of Sn, we consider the definition and classification of extraspecial p-groups and focus on such a group: S(p.n). We show that nc(S(2, n)) = 2n+ 1 and that S(p, n) ≥ pn+ 1.

In this paper we discuss some partial solutions of the length conjecture which describes the length of a generating system for matrix algebras. We consider mainly the algebras generated by two matrices which are quasi-commuting. It is shown that in this case the length function is linearly bounded. We also analyze which particular natural numbers can be realized as the lengths of certain specia...