Can the cosmological constant undergo abrupt changes?

The existence of a simple spherically symmetric and static solution of the Einstein equations in the presence of a cosmological constant vanishing outside a definite value of the radial distance is investigated. A particular succession of field configurations, which are solutions of the Einstein equations in the presence of the considered cosmological term and auxiliary external sources, is constructed. Then, it is shown that the associated succession of external sources tend to zero in the sense of the generalized functions. The type of weak solution that is found becomes the deSitter homogeneous space-time for the interior region, and the Schwartzschild space in the outside zone.Comment: 10 pages, 1 figur

Exploring effects of strong interactions in enhancing masses of dynamical origin

A previous study of the dynamical generation of masses in massless QCD is considered from another viewpoint. The quark mass is assumed to have a dynamical origin and is substituted by a scalar field without self-interaction. The potential for the new field background is evaluated up to two loops. Expressing the running coupling in terms of the scale parameter $\mu$, the potential minimum is chosen to fix $m_{top}=175$ $GeV$ when $\mu_0=498$ $MeV$. The second derivative of the potential predicts a scalar field mass of 126.76 $GeV$. This number is close to the value 114 $GeV$ which, preliminary data taken at CERN, suggested to be associated with the Higgs particle. However, the simplifying assumptions limit the validity of the calculations done, as indicated by the large value of $\alpha=\frac {g^2}{4\pi}=1.077$ obtained. However, supporting statements about the possibility of improving the scheme come from the necessary inclusion of weak and scalar field couplings and mass counterterms in the renormalization procedure, in common with the seemingly needed consideration of the massive W and Z fields, if the real conditions of the SM model are intended to be approached.Comment: 10 pages, 4 figures, a numerical error was corrected as well as the values of the estimated parameters which it determined. The discussion and arguments were also improve