Modern Physics Letters A

We review the present status of the QCD corrected cross-sections and kinematic distributions for the production of a Higgs boson in association with bottom quarks at the Fermilab Tevatron and CERN Large Hadron Collider. Results are presented for the Minimal Supersymmetric Standard Model where, for large tan β, these production modes can be greatly enhanced compared to the Standard Model case. The next-to-leading order QCD results are much less sensitive to the renormalization and factorization scales than the lowest order results, but have a significant dependence on the choice of the renormalization scheme for the bottom quark Yukawa coupling. We also investigate the uncertainties coming from the Parton Distribution Functions and find that these uncertainties can be comparable to the uncertainties from the remaining scale dependence of the next-to-leading order results. We present results separately for the different final states depending on the number of bottom quarks identified.

We review series of multiqubit Bell's inequalities which apply to correlation functions and present conditions that quantum states must satisfy to violate such inequalities.

We present a simple mechanism to eliminate cosmological constants both in supersymmetric and non-supersymmetric theories. This mechanism is based on the Hodge (Poincaré) duality between a 0-form and D-form field strengths in D-dimensional spacetime. The new key ingredient is the introduction of an extra Chern–Simons term into the D-form field strength H dual to the 0-form field strength. Our formulation can also be made consistent with supersymmetry. Typical applications to four-dimensional N = 1 supergravity and to ten-dimensional type IIA supergravity are given. The success of our formulation for both supersymmetric and non-supersymmetric systems strongly indicates the validity of our mechanism even after supersymmetry breakings at the classical level. Our mechanism may well be applicable to quantized systems, at least for supersymmetric cases with fundamental D-brane actions available.

By extending the statistical distributions to the transverse degree of freedom, we account for a multiplicative factor in the Fermi–Dirac functions of the light quarks, we were led to introduce in a previous work to comply with experiment. We can also get light antiquark distributions, similar to those we proposed earlier.

In this letter we introduce a particular solution for parallel electric and magnetic fields, in a gravitational background, which satisfy free-wave equations and the phenomenology suggested by astrophysical plasma physics. These free-wave equations are computed such that the electric field does not induce the magnetic field and vice versa. In a gravitational field, we analyze the Maxwell equations and the corresponding electromagnetic waves. A continuity equation is presented. A commutative and noncommutative analysis of the electromagnetic duality is described.

A solution of codimension 2 brane is found for which four-dimensional Friedmann cosmology is recovered on the brane with time-dependent tension, in the Einstein frame. The effective parameter p/ρ of equation of state on the brane can be quintessence like, de Sitter like or phantom like, depending on the integration constants of the solution.

Back reaction in the Schwarzschild–de Sitter black hole in thermal equilibrium with conformal massless quantum field is discussed using the method of York. The presence of quantum field and back reaction ensures the entropy of dressed black hole. In the perturbed spacetime geometry, the nature of the effective potential and the orbits of massless and massive particles are also investigated.