Modern Physics Letters A

It is shown that a 4D N = 1 softly broken supersymmetric theory with higher derivative operators in the Kahler or the superpotential part of the Lagrangian and with an otherwise arbitrary superpotential, can be re-formulated as a theory without higher derivatives but with additional (ghost) superfields and modified interactions. The importance of the analytical continuation Minkowski–Euclidean space–time for the UV behaviour of such theories is discussed in detail. In particular it is shown that power counting for divergences in Minkowski space–time does not always work in models with higher dimensional (derivative) operators.

Adding a second scalar doublet (η⁺, η⁰) and three neutral singlet fermions N_{1, 2, 3} to the Standard Model of particle interactions with a new Z₂ symmetry, it has been shown that or is a good dark-matter candidate and seesaw neutrino masses are generated radiatively. A supersymmetric U(1) gauge extension of this new idea is proposed, which enforces the usual R-parity of the Minimal Supersymmetric Standard Model, and allows this new Z₂ symmetry to emerge as a discrete remnant.

There are large classes of inflationary models, particularly popular in the context of string theory and braneworld approaches to inflation, in which the ratio of linearized tensor-to-scalar metric fluctuations is very small. In such models, however, gravitational waves produced by scalar modes cannot be neglected. We derive the lower bound on the tensor-to-scalar ratio by considering the back-reaction of the scalar perturbations as a source of gravitational waves. These results show that no cosmological model that is compatible with a metric scalar amplitude of ≈10^-5 can have a ratio of the tensor-to-scalar power spectra less than ≈10^-8 at recombination and that higher-order terms leads to logarithmic growth for r during radiation domination. Our lower bound also applies to non-inflationary models which produce an almost scale-invariant spectrum of coherent super-Hubble scale metric fluctuations.

The paper presents in all its nontrivial details the sp(3) BRST Hamiltonian formalism. It is based on structuring the extended phase space on many levels. In this picture, the standard BRST symmetry appears as being only the first approximation of a generalized symmetry, acting as a horizontal (same level) operator. The gauge-fixing problem is completely solved by formulating a theorem and a general rule which allow the choice of a simple gauge term. As an example, the Hamiltonian sp(3) quantization of the Yang–Mills model is exhaustively presented.

Supersymmetry (SUSY) in quantum mechanics is extended from square integrable states to those satisfying the outgoing wave boundary condition. Using this formalism we obtain new exactly solvable potentials admitting quasinormal modes (QNM) solutions of the Klein–Gordon equation.

The Euclidean thermal Green function of the two-dimensional (2D) free massless scalar field in coordinate space is written as the real part of a complex analytic function of a variable that conformally maps the infinite strip -∞ < x < ∞ (0 < τ < β) of the z = x + iτ (τ: imaginary time) plane into the upper-half-plane. Using this fact and the Cauchy–Riemann conditions, we identify the dual thermal Green function as the imaginary part of that function. Using both the thermal Green function and its dual, we obtain an explicit series expression for the fermionic correlation functions of the massive Thirring model (MTM) at a finite temperature.

We investigate the conservation law of energy–momentum for Randall–Sundrum models by the general displacement transform. The energy–momentum current has a superpotential and are therefore identically conserved. It is shown that for Randall–Sundrum solution, the momentum vanishes and most of the bulk energy is localized near the Planck brane. The energy density is ε = ε₀ e^-3k|y|.