Modern Physics Letters A

The theory of cometary panspermia is reviewed in relation to evidence from astronomy, biology and recent studies of meteorites. The spectroscopic signatures in interstellar material within our galaxy and in external galaxies that have been known for many years most plausibly represent evidence for the detritus of life existing on a cosmic scale. Such spectral features discovered in galaxies of high redshift points to life arising at a very early stage in the history of the Universe. Evidence of fossils of microscopic life forms in meteorites that have been discussed over several decades, and augmented recently with new data, reaffirms the case for cometary panspermia.

The dependence of inclusive one jet differential cross-section on the renormalization and factorization scale is studied. The choice when both scales μ_r, μ_f are set equal to jet transversal momentum is taken as a referential point and within a region around this choice, the inclusive one jet differential cross-section is calculated at next-to-leading order. Following the principle of minimal sensitivity (PMS), the region of local stability with respect to both scales is searched for. It is shown that it is well approximated by particular choice for total energies 7000 and 14,000 GeV.

We start systematic investigation for the possibility to have supersymmetry (SUSY) as an asymptotic state of the gauge theory in the high energy (UV) limit, due to the renormalization group running of coupling constants of the theory. The answer on whether this situation takes place or not, can be resolved by dealing with the running of the ratios between Yukawa and scalar couplings to the gauge coupling. The behavior of these ratios does not depend too much on whether gauge coupling is asymptotically free (AF) or not. It can be shown that the UV stable fixed point for the Yukawa coupling is not supersymmetric. Taking this into account, one can break down SUSY only in the scalar coupling sector. We consider two simplest examples of such breaking, namely N = 1 supersymmetric QED and QCD. In one of the cases one can construct an example of SUSY being restored in the UV regime.

We have investigated the effects of different hadronic form factors on the performance of an isobaric model developed for kaon photo-production off the proton. We found that there is no ideal form factor in this case. The dipole and generalized dipole form factors can help to nicely reproduce the differential cross-section and hyperon polarization data. However, in the case of double polarization data C_x and C_z the Gaussian form factor is found to be superior.

We propose a new type of cosmological model derived from the fractional variational principle when it is applied to the gravitational sector of action functional. In contrast to the fractional cosmological model developed earlier by the author from a fractional total action, in our new model the continuity equation remains valid in its usual form. For this model, a lot of exact solutions are obtained from a specific ansatz which is proposed for the cosmological term in this paper. Several examples arising from the given variations of the Hubble parameter with time are provided. Besides, we suggest an original interpretation of the main equations for our model. It supposes that the effective cosmological term could arise as a result of kinematical induction through the nonzero Hubble parameter. With the help of particular example, we demonstrate how this approach could lead our model quite closer to the real behavior of the universe.

In this paper, we propose a new method to use the strong lensing data sets to constrain a cosmological model. By taking the ratio as cosmic observations, one can completely eliminate the uncertainty caused by the relation σ_SIS = f_Eσ₀ which characterizes the relation between the stellar velocity dispersion σ₀ and the velocity dispersion σ_SIS. Via our method, a relative tight constraint to the cosmological model space can be obtained, for the spatially flat ΛCDM model as an example in 3σ regions. And by using this method, one can also probe the nature of dark energy and the spatial curvature of our Universe.

We explore the Jacobi last multiplier (JLM) as a means for deriving the Lagrangian of a fourth-order differential equation. In particular, we consider the classical Pais–Uhlenbeck problem and write down the accompanying Hamiltonian. We then compare such an expression with our alternative derivation of the Hamiltonian that makes use of the Ostrogradski's method and show how a mapping from the one to the other is achievable by variable transformations.