International Journal of Modern Physics A

In this paper, we investigate the Drell–Yan process with the intermediate heavy Z′ boson. We use a general approach to the Abelian Z′ that utilizes the renormalization-group relations between the Z′ couplings and allows to reduce the number of unknown Z′ parameters significantly. In a newly proposed strategy, we estimate the LHC-driven constraints for the Z′ couplings to lepton and quark vector currents. To do this, we calculate the Z′-related contribution in the narrow-width approximation and compare the obtained values to the experimental data presented by the ATLAS and CMS collaborations. Our method allows to estimate the values of Z′ couplings to the u and d quarks and to final-state leptons.

In this work, on the condition that scalar potential is equal to vector potential, the bound state solutions of the Klein–Fock–Gordon equation of the Manning–Rosen plus ring-shaped like potential are obtained by Nikiforov–Uvarov method. The energy levels are worked out and the corresponding normalized eigenfunctions are obtained in terms of orthogonal polynomials for arbitrary l states. The conclusion also contain central Manning–Rosen, central and noncentral Hulthén potential.

In this paper, we investigate the classical and quantum aspects of five-dimensional Chern–Simons theory. As a constrained Hamiltonian system we compute the Dirac brackets among the canonical variables for the Abelian case. In terms of the Batalin–Vilkovisky formalism, we show that the classical master equation leads to new algebraic constraints on the Lie algebra. Finally, partition function and geometric quantization of the theory have been also discussed.

It has been known for 30 years that 't Hooft–Polyakov monopoles of charge Q greater than one cannot be spherically symmetric. Five years ago, Bolognesi conjectured that, at some point in their moduli space, BPS monopoles can become approximately spherically symmetric in the high Q limit. In this paper, we determine the sense in which this conjecture is correct. We consider an SU(2) gauge theory with an adjoint scalar field, and numerically find configurations with Q units of magnetic charge and a mass which is roughly linear in Q, for example, in the case Q = 81 we present a configuration whose energy exceeds the BPS bound by about 54%. These approximate solutions are constructed by gluing together Q cones, each of which contains a single unit of magnetic charge. In each cone, the energy is largest in the core, and so a constant energy density surface contains Q peaks and thus resembles a sea urchin.

We consider an extension of the Standard Model within the framework of Noncommutative Geometry. The model is based on an older model [C. A. Stephan, Phys. Rev. D79, 065013 (2009)] which extends the Standard Model by new fermions, a new U(1)-gauge group and, crucially, a new scalar field which couples to the Higgs field. This new scalar field allows to lower the mass of the Higgs mass from ~170 GeV, as predicted by the Spectral Action for the Standard Model, to a value of 120–130 GeV. The shortcoming of the previous model lay in its inability to meet all the constraints on the gauge couplings implied by the Spectral Action. These shortcomings are cured in the present model which also features a "dark sector" containing fermions and scalar particles.

In this paper, we construct the fuzzy (finite-dimensional) analogs of the conifold Y⁶ and its base X⁵. We show that fuzzy X⁵ is (the analog of) a principal U(1) bundle over fuzzy spheres and explicitly construct the associated monopole bundles. In particular, our construction provides an explicit discretization of the spaces T^{κ, κ} and T^{κ, 0}.

It is shown that all the known uncertainty relations are the secondary consequences of Robertson's relation. The basic idea is to use the Heisenberg picture so that the time development of quantum mechanical operators incorporate the effects of the measurement interaction. A suitable use of triangle inequalities then gives rise to various forms of uncertainty relations. The assumptions of unbiased measurement and unbiased disturbance are important to simplify the resulting uncertainty relations and to give the familiar uncertainty relations, such as a naive Heisenberg error-disturbance relation. These simplified uncertainty relations are however, valid only conditionally. Quite independently of uncertainty relations, it is shown that the notion of precise measurement is incompatible with the assumptions of unbiased measurement and unbiased disturbance. We can thus naturally understand the failure of the naive Heisenberg's error-disturbance relation, as was demonstrated by the recent spin measurement by Erhart et al.