The form factors existing in the b->s g^* decay and the possible CP violating effects in the noncommutative standard model

We study the form factors appearing in the inclusive decay b -> s g^*, in the framework of the noncommutative standard model. Here g^* denotes the virtual gluon. We get additional structures and the corresponding form factors in the noncommutative geometry. We analyse the dependencies of the form factors to the parameter p\Theta k where p (k) are the four momenta of incoming (outgoing) b quark (virtual gluon g^*, \Theta is a parameter which measures the noncommutativity of the geometry. We see that the form factors are weaklyComment: 8 pages, 7 figure

Modelling of the crystallization front – particles interactions in ZnAl/(SiC)p composites

The presented work focuses on solid particle interactions with the moving crystallization front during a solidification of the metal matrix composite. The current analyses were made for silicon carbide particles and ZnAl alloy with different additions of aluminium. It was found, that the chemical composition of the metal matrix influences the behaviour of SiC particles. At the same time calculations of the forces acting on a single particle near the crystallization front were performed. For each alloy type the critical conditions that determine whether particle will be absorbed or pushed, were specified

Review of the Phenomenology of Noncommutative Geometry

We present a pedagogical review of particle physics models that are based on the noncommutativity of space-time, $[\hat{x}_\mu,\hat{x}_\nu]=i \theta_{\mu \nu}$, with specific attention to the phenomenology these models predict in particle experiments either in existence or under development. We summarize results obtained for high energy scattering such as would occur for example in a future $e^+e^-$ linear collider with $\sqrt{s} = 500 GeV$, as well as low energy experiments such as those pertaining to elementary electric dipole moments and other \cpviolng observables, and finally comment on the status of phenomenological work in cosmology and extra dimensions.Comment: updated, references added, corrected typo

Non-commutative U(1) Super-Yang-Mills Theory: Perturbative Self-Energy Corrections

The quantization of the non-commutative N=1, U(1) super-Yang-Mills action is performed in the superfield formalism. We calculate the one-loop corrections to the self-energy of the vector superfield. Although the power-counting theorem predicts quadratic ultraviolet and infrared divergences, there are actually only logarithmic UV and IR divergences, which is a crucial feature of non-commutative supersymmetric field theories.Comment: 18 pages, latex, uses feynmf package; references added, Wess-Zumino gauge remove

High-Temperature Effective Potential of Noncommutative Scalar Field Theory: Reduction of Degree of Freedom by Noncommutativity

The renormalization of effective potentials for the noncommutative scalar field theory at high temperature are investigated to the two-loop approximation. The Feynman diagrams in evaluating the effective potential may be classified into two types: the planar diagrams and nonplanar diagrams. The nonplanar diagrams, which depend on the parameter of noncommutativity, do not appear in the one-loop potential. Despite their appearance in the two-loop level, they do not have an inclination to restore the symmetry breaking in the tree level, in contrast to the planar diagrams. This phenomenon is explained as a consequence of the drastic reduction of the degrees of freedom in the nonplanar diagrams when the thermal wavelength is smaller than the noncommutativity scale. Our results show that the nonplanar two-loop contribution to the effective potential can be neglected in comparsion with that from the planar diagrams.Comment: Latex, 17 pages, change the conclusion, improve the Englis

Compton scattering in Noncommutative Space-Time at the NLC

We study the Compton scattering in the noncommutative counter part of QED (NC QED). Interactions in NC QED have momentum dependent phase factors and the gauge fields have Yang Mills type couplings, this modifies the cross sections and are different from the commuting Standard Model. Collider signals of noncommutative space-time are studied at the Next Linear Collider (NLC) operating in the $e \gamma$ mode. Results for different polarised cases are presented and it is shown that the Compton process can probe the noncommutative scale in the range of 1 - 2.5 TeV for typical proposed NLC energies.Comment: 12 pages, 5 Postscript figures, version to appear in Phys. Rev.