Modern Physics Letters A

Three generations of leptons and quarks correspond to the lepton charges (LCs) in this work. Then, the leptons have the electric charges (ECs) and LCs. The quarks have the ECs, LCs and color charges (CCs). Three heavy leptons and three heavy quarks are introduced to make the missing third flavor of EC. Then the three new particles which have the ECs are proposed as the bastons (dark matters) with the rest masses of 26.121 eV/c², 42.7 GeV/c² and 1.9 × 10${}^{15}$ eV/c². These new particles are applied to explain the origins of the astrophysical observations like the ultra-high energy cosmic rays and supernova 1987A anti-neutrino data. It is concluded that the 3.5 keV X-ray peak observed from the cosmic X-ray background spectra is originated not from the pair annihilations of the dark matters but from the X-ray emission of the Q1 baryon atoms which are similar in the atomic structure to the hydrogen atom. The presence of the 3.5 keV cosmic X-ray supports the presence of the Q1 quark with the EC of −4/3. New particles can be indirectly seen from the astrophysical observations like the cosmic ray and cosmic gamma ray. In this work, the systematic quantized charges of EC, LC and CC for the elementary particles are used to consistently explain the decay and reaction schemes of the elementary particles. Also, the strong, weak and dark matter forces are consistently explained.

A cosmological model with a fermionic field and a massive bosonic field within the framework of the Einstein–Cartan theory is developed. The spacetime curvature is due to the matter-energy of the gravitational sources, whereas the torsion of the spacetime manifold follows from the spin density. From the numerical simulations it is shown that the fermionic spin density and the bosonic constituent answer for the transition from a decelerated to an accelerated era. The massive bosonic field behaves as dark energy, as it promotes the final accelerated period. During the initial decelerated era both constituents contribute, and the transition occurs as the torsion effect decreases with time. The exchange of energy between the constituents occurs via the gravitational field.

This paper investigates the existence of Noether symmetries of some anisotropic homogeneous universe models in non-minimally coupled f(R, T) gravity (R and T represent Ricci scalar and trace of the energy–momentum tensor). We evaluate symmetry generators and the corresponding conserved quantities for two models of this theory admitting direct and indirect non-minimal curvature–matter coupling. We also discuss exact solutions for dust as well as non-dust matter distribution and study the physical behavior of some cosmological parameters through these solutions. For dust distribution, the exact solution corresponds to power-law expansion and Einstein universe while exponential expansion appears for non-dust matter. The graphical analysis of these solutions and cosmological parameters provide consistent results with recent observations about accelerated cosmic expansion. We conclude that Noether symmetry generators and conserved quantities exist for both models.

We study the phenomenological implications of breaking the Tri-Bimaximal (TBM) mixing in such a way that either first or second column of TBM mixing matrix remains invariant. We present two such textures and confront them with the experimental data. We give the predictions of these textures for atmospheric mixing angle ${𝜃}_{23}$ and Dirac-type CP violating phase $\delta$ that will be measured in the future experiments.

In this paper, the quantum mechanics on the (anti) de Sitter background is investigated. the extended uncertainty principle and the deformed calculus are discussed for the quantum mechanics on the (anti)-de Sitter background. As examples one-dimensional box problem and one-dimensional harmonic oscillator problem are discussed.

The observation of the $Y(4140)$ structure in $B^{\pm }\to J/\psi \varphi K^{\pm }$ decays produced in $\bar{p}p$ collisions at $\sqrt{s}=1.96$ TeV is reported with a statistical significance greater than 5 standard deviations. A fit to the $J/\psi \varphi$ mass spectrum is performed assuming the presence of a Breit–Wigner resonance. The fit yields a signal of $19\pm 6(\mathrm{\text{stat}})\pm 3(\mathrm{\text{syst}})$ resonance events, and resonance mass and width of $4143.4_{-3.0}^{+2.9}(\mathrm{\text{stat}})\pm 0.6(\mathrm{\text{syst}})\mathrm{\text{MeV}}/c^2$ and $15.3_{-6.1}^{+10.4}(\mathrm{\text{stat}})\pm 2.5(\mathrm{\text{syst}})\mathrm{\text{MeV}}/c^2$, respectively. The parameters of this resonance-like structure are consistent with values reported from an earlier CDF analysis.

We show the kinematic equivalence between cosmological models driven by Dirac–Born–Infeld (DBI) fields $\varphi$ with constant proper velocity of the brane and exponential potential $V=V_0{e}^{-B\varphi }$, and interactive cosmological systems with modified holographic Ricci type fluids as dark energy (DE) in flat Friedmann–Robertson–Walker (FRW) cosmologies.