Modern Physics Letters A

We summarize the results showing that all existing data on mixing between up and down fermion states (i.e. CKM matrix and neutrino oscillations) and on the hierarchical quark and lepton mass ratios between generations are consistent with the two phenomena being both consequences of a mass matrix rotating in generation space with changing energy scale. Thus the rotation of the mass matrix can be traced over some 14 orders of magnitude in energy from the mass scale of the t-quark at 175 GeV to below that of the atmospheric neutrino at 0.05 eV.

The interaction of light quarks and instanton liquid is analyzed at finite density of quark/baryon matter and in the phase of nonzero values of diquark (colour) condensate. It is shown that instanton liquid perturbation produced by such an interaction results in an essential increase of the critical value of quark chemical potential μ_c which provokes the perceptible increase of quark matter density around the expected onset of the colour superconductivity phase.

We consider a model of interacting cosmological constant/quintessence, where dark matter and dark energy behave as, respectively, two coexisting phases of a fluid, a thermally excited Bose component and a condensate, respectively. In a simple phenomenological model for the dark components interaction we find that their energy density evolution is strongly coupled during the universe evolution. This feature provides a possible way out for the coincidence problem affecting many quintessence models.

In this work, we pursue further consequences of a general formalism for non-covariant gauges developed in an earlier work (hep-th/0205042). We carry out further analysis of the additional restrictions on renormalizations noted in that work. We use the example of the axial gauge A₃ = 0. We find that if multiplicative renormalization together with ghost-decoupling is to hold, the "prescription-term" (that defines a prescription) cannot be chosen arbitrarily but has to satisfy certain nontrivial conditions (over and above those implied by the validity of power counting) arising from the WT identitites associated with the residual gauge invariance. We also give a restricted class of solutions to these conditions.

We improve a result obtained in Ref. 2: In the context of supersymmetric quantum mechanics we present a certain superpotential that yields a trial function we use for the calculation of variational quantum bound state energies of the screened Coulomb potential. We show that for small screening parameters our trial function yields better approximations for the energies than the trial function used in Ref. 2.

The properties of new heavy mesons containing new heavy quarks have been investigated. As an example, the fourth SM family quarks and weak iso-singlet quarks predicted by E₆ GUT are considered. Production of these hadrons at TeV energy lepton colliders due to resonant formation of corresponding quarkonia have been analyzed.

The propagation of a free scalar field ϕ with mass m in a curved background is generally described by the equation (g^μν∇_μ∇_ν + m² + ξR)ϕ = 0. There exist some arguments in the literature that seem to favor the conformal coupling to the detriment of the minimal one. However, the majority of these claims are inconclusive. Here we show that the exact Foldy–Wouthuysen transformation for spin-0 particle coupled to a wide class of static spacetime metrics exists independently of the value of ξ. Nevertheless, if the coupling is of the conformal type, the gravitational Darwin-like term has an uncomplicated structure and it is proportional to the corresponding term in the fermionic case. In addition, an independent computation of this term, which has its origin in the zitterbewegung fluctuation of the boson's position with the mean square <(δr)²> ≈ 1/m², gives a result that coincides with that obtained using the aforementioned exact transformation with ξ = 1/6.