Modern Physics Letters A

We suggest that the Standard Model can be viewed as the magnetic dual of a gauge theory featuring only fermionic matter content. We show this by first introducing a Pati–Salam like extension of the Standard Model and then relating it to a possible dual electric theory featuring only fermionic matter. The absence of scalars in the electric theory indicates that the associated magnetic theory is free from quadratic divergences. Our novel solution to the Standard Model hierarchy problem leads also to a new insight on the mystery of the observed number of fundamental fermion generations by naturally explaining why it has to be at least three.

Lowest-order cumulants provide important information on the shape of the emission source in femtoscopy. For the simple case of noninteracting identical particles, we show how the fourth-order source cumulant can be determined from measured cumulants in momentum space. The textbook Gram–Charlier series is found to be highly inaccurate, while the related Edgeworth series provides increasingly accurate estimates. Ordering of terms compatible with the Central Limit Theorem appears to play a crucial role even for non-Gaussian distributions.

The pair production of tau sneutrinos in e⁺e^- collisions and their subsequent decays are studied in a framework of the supersymmetric extension of the standard model. We present an analysis for the parameter space (branching versus mass) with the beam polarization capability. The tau sneutrino can be observed up to a mass of 1 TeV if the branching is around 0.35 at the linear collider with and integrated luminosity of 1 ab^-1.

In this paper, based on Kubo's formula and the QCD low energy theorem, we propose a direct formula for calculating the bulk viscosity of QCD at finite chemical potential μ and zero temperature. According to this formula, the bulk viscosity at finite μ is totally determined by the dressed quark propagator at finite μ. We then use a dynamical, confining Dyson–Schwinger equation model of QCD to calculate the bulk viscosity at finite μ. It is found that no sharp peak behavior of the bulk viscosity at finite μ is observed, which is quite different from that of the bulk viscosity at finite temperature.

We examine capabilities of the modified perturbation theory (MPT) for description of the processes with productions and decays of fundamental unstable particles. We calculate total cross-section for e⁺e^- → γ, Z → W⁺W^- → 4f in a model with the Dyson-resummed and with the MPT-expanded up to the NNLO Breit–Wigner factors, and compare the outcomes. At the ILC energies a coincidence of the outcomes is detected with precision better than one per-mille.

The two ways of counting microscopic states of black holes in the U(1) formulation of loop quantum gravity: one counting all allowed spin network labels j, m and the other only m labels, are discussed in some detail. The constraints on m are clarified and the map between the flux quantum numbers and m discussed. Configurations with |m|=j, which are sometimes sought after, are shown to be important only when large areas are involved. The discussion is extended to the SU(2) formulation.

We discuss the target space pseudoduality in supersymmetric sigma models on symmetric spaces using two different methods, orthonormal coframe and component expansion. These two methods yield similar results to the classical cases with the exception that commuting bracket relations in classical case turn out to be anticommuting ones because of the appearance of Grassmann numbers. In component expansion method it is understood that constraint relations in case of non-mixing pseudoduality are the remnants of mixing pseudoduality. Once mixing terms are included in the pseudoduality relations, the constraint relations disappear.