We prove that if T = T eq is a stable theory (without the finite cover property), then the theory TP of “beautiful pairs” eliminates imaginaries if and only if no infinite group is definable in a model of T .

The paper concerns the automorphism groups of Cayley graphs over cyclic groups which have a rational spectrum (rational circulant graphs for short). With the aid of the techniques of Schur rings it is shown that the problem is equivalent to consider the automorphism groups of orthogonal group block structures of cyclic groups. Using this observation, the required groups are expressed in terms o...

Over the last thirty years, various combinatorial aspects of finite metric spaces have been studied in the context of phylogenetic-tree reconstruction. A starting point was the following observation: Given a metric D : X × X → R representing the approximative genetic distances D(x, y), . . . between the members x, y, . . . of a finite collection X of taxa, it was shown in [15] that the followin...

In this brief paper we adress spontaneous symmetry breaking in a finite-temperature scalar meson plasma. We calculate the in-medium averaged thermal σ − σ scattering crossection and the related shear viscosity η(T) and mean-free-path L(T). Our results suggest that slightly below the critical temperature there is a 30 percent peak in the crossection leading to equivalent dips in η(T) and L(T). W...

Coronary pseudoaneurysm after bare-metal stent implantation is a rare event. Observation, surgical resection, or implantation of another stent, bare or covered, are alternative and equivalent management options. Since no option prevails over the other, the most appropriate treatment should be evaluated in every single patient. We report the case of a pseudoaneurysm within a stent with diffuse r...

In this paper, we present a new approach to linearizing zero-one quadratic minimization problem which has many applications in computer science and communications. Our algorithm is based on the observation that the quadratic term of zero-one variables has two equivalent piece-wise formulations, convex and concave cases. The convex piece-wise objective function and/or constraints play a great ro...

The model from Gao and Owen (2017) applied those U-statistics to Yij instead of ηij . In our notation, their Yij = μ+ ηij . Because the intercept μ cancels, these U-statistics defined via ηij are equivalent to those defined via Yij . Theorem 9.1. Let Yij follow the random effects model (1) with the observation pattern Zij as described in Section 2. Then the U -statistics defined at (100) have v...

In the naive form of most resummations we get into conflict with order-by-order renormalization. We present a method that is capable to ensure UV consistency of any resummations satisfying certain conditions. The method is based on the observation that resummation is equivalent with a calculation in an adequate perturbation scheme, followed by a renormalization scheme changing. This framework w...

We extend a low-rate improvement of the random coding bound on the reliability of a classical discrete memoryless channel to its quantum counterpart. The key observation that we make is that the problem of bounding below the error exponent for a quantum channel relying on the class of stabilizer codes is equivalent to the problem of deriving error exponents for a certain symmetric classical cha...

We propose to use periodically spaced, curved optical waveguides for observation of optical Bloch oscillations. The refractive index distribution in this system is equivalent to the sum of a periodic term resulting from the equal spacing of the waveguides and a linear ramp, created by the curvature. We demonstrate numerically that light propagation in this geometry exhibits spatial Bloch oscill...