The European Physical Journal Plus

By considering the confinement of the Aharonov-Casher system to a Coulomb-type potential, we show that the energy levels depends on the Aharonov-Casher geometric phase and obtain the persistent spin currents. Besides, we investigate the influence of the Coulomb-type potential on the Landau-Aharonov-Casher system by showing that bound states solutions to the Schrödinger-Pauli equation can be obtained. We show that the Landau-Aharonov-Casher cyclotron frequency is modified and discuss a quantum characterized by the dependence of the angular frequency on the quantum numbers of the system. As a particular case, we calculate the possible values of the angular frequency associated with the ground state.

Solar wind disturbances such as coronal mass ejections and their interplanetary counterparts and corotating interaction regions are interconnected with solar-terrestrial parameters such as cosmic rays, solar wind, geomagnetic storm, lightning, interplanetary magnetic field, among others. Data selection remains a challenging problem in solar-terrestrial studies. While manual selection of Forbush decreases (FDs) is subjective, automated methods are not widely used within the field. We demonstrate that Forbush events algorithm selection technique is an improvement over the common but inefficient manual method. Additionally, a simple coincident computer program was used to select other solar-terrestrial variables using the FD date as the input data. We used models/tools capable of handling simultaneous multidimensional variables to study the complex interrelationships within the Sun–Earth space. Forbush effects (FEs) selected by the IZMIRAN group was used to validate our results. Fourier transform technique and an R-based algorithm were used to identify FDs from Sanae neutron monitor data. In order to select other solar/geophysical variables, the program-selected FD dates were used as input data for the coincident algorithm. The large number of variables selected were analyzed using principal component analysis and multiple regression models. Several analyses showed that variability in solar-terrestrial parameters happens simultaneously with FDs. We conclude that data fluctuations within the Sun–Earth region might be induced simultaneously by common solar events and should be investigated using multidimensional models.

I construct a thin-shell wormhole in the spherically symmetric, static Bertotti-Robinson magnetic universe which is supported by normal matter in the sense that the energy conditions are all satisfied. Using the so called small velocity perturbation it is shown that this thin-shell wormhole is basically physical but unstable against radial perturbation.

The quantum concurrence of $$\textit{SU}(2) \otimes \textit{SU}(2)$$ spin–parity states is shown to be invariant under $$\textit{SO}(1,3)$$ Lorentz boosts and O(3) rotations when the density matrices are constructed in consonance with the covariant probabilistic distribution of Dirac massive particles. Similar invariance properties are obtained for the quantum purity and for the trace of unipotent density matrix operators. The reported invariance features—obtained in the scope of the $$\textit{SU}(2) \otimes \textit{SU}(2)$$ corresponding to just one of the inequivalent representations enclosed by the $$\textit{SL}(2,{\mathbb {C}})\otimes \textit{SL}(2,{\mathbb {C}})$$ symmetry—set a more universal and kinematical-independent meaning for the quantum entanglement encoded in systems containing not only information about spin polarization but also the correlated information about intrinsic parity. Such a covariant framework is used for computing the Lorentz invariant spin–parity entanglement of spinorial particles coupled to a magnetic field, through which the extensions to more general Poincaré classes of spinor interactions are straightforwardly depicted.

Variational mass-consistent models for the velocity field v have been used by mesoscale meteorological community to modeling the wind field from an observed field v 0 in a bounded region Ω with boundary Γ. Variational calculus reduces the problem to the solution of an elliptic equation for a Lagrange multiplier λ subject to Dirichlet Boundary Condition (DBC) on flow-through boundaries. In this work, it is shown that DBC decreases the regularity of λ and this in turn decreases the accuracy with which the velocity field satisfies the mass-balance. The boundary condition (BC) v · n = v T · ngiven by the true field v T on the whole boundary Γ, leads only to a Neumann boundary condition (NBC) for λ. Approximations of this BC are studied. Analytic and numerical results show that the velocity field U 0 obtained from v 0 by direct integration of the continuity equation, yields a NBC that improves significantly the fields obtained with DBC’s.

Bài viết tổng hợp các phòng thí nghiệm dưới lòng đất và các thí nghiệm vật lý hạt ở Trung Quốc. Phòng thí nghiệm dưới lòng đất Jinping ở núi Jinping, Tứ Xuyên, Trung Quốc là phòng thí nghiệm dưới lòng đất sâu nhất thế giới với lối vào nằm ngang. Độ dày lớp đá che chở trong phòng thí nghiệm này vượt quá 2400 m. Lưu lượng tia vũ trụ và độ phóng xạ của các mẫu đá địa phương được đo là rất thấp. Các thí nghiệm với germanium tinh khiết cao đang thu thập dữ liệu cho việc tìm kiếm vật chất tối trực tiếp. Thí nghiệm với xenon lỏng đang trong quá trình xây dựng. Đề xuất thành lập Phòng thí nghiệm dưới lòng đất quốc gia Trung Quốc với thể tích lớn tại Jinping cho nghiên cứu đa ngành được thảo luận.

We obtain an exact analytical solution to Einstein’s field equations assuming a non-linear equation-of-state and a particular mass function. Our solution describes the interior of anisotropic color flavor locked strange quark stars. All energy conditions are fulfilled, and therefore the solution obtained here is a realistic solution within General Relativity. The mass-to-radius profile is obtained, and the compactness of the star is computed.

The D-dimensional Schrodinger equation with generalized Cornell potential (GCP) is transformed into a form that is compatible with extended Nikiforov–Uvarov (ENU) method, and its approximate solutions are obtained using this formalism. The energy spectrum for the GCP is obtained in closed form, and the wave function is determined using the biconfluent Heun differential equation. Some numerical results are shown to illustrate the behaviour of the bound state energies at different quantum states for various dimensions and selected diatomic molecular systems. In addition, the thermodynamic property expressions for GCP are obtained in closed form, and their variation with temperature is discussed extensively for various dimensions and selected diatomic molecular systems. In addition, the mass spectra of GCP and their special cases are studied for heavy mesons. Our results agree with those obtained in the literature.