Critical velocities c/3c/\sqrt 3 and c/2c/\sqrt 2 in general theory of relativity

We consider a few thought experiments of radial motion of massive particles in the gravitational fields outside and inside various celestial bodies: Earth, Sun, black hole. All other interactions except gravity are disregarded. For the outside motion there exists a critical value of coordinate velocity ${\rm v}_c = c/\sqrt 3$: particles with ${\rm v} < {\rm v}_c$ are accelerated by the field, like Newtonian apples, particles with ${\rm v} > {\rm v}_c$ are decelerated like photons. Particles moving inside a body with constant density have no critical velocity; they are always accelerated. We consider also the motion of a ball inside a tower, when it is thrown from the top (bottom) of the tower and after classically bouncing at the bottom (top) comes back to the original point. The total time of flight is the same in these two cases if the initial proper velocity $v_0$ is equal to $c/\sqrt 2$.Comment: 13 page

Do neutrino oscillations allow an extra phenomenological parameter?

The quantity $\xi$ introduced recently in the phenomenological description of neutrino oscillations is in fact not a free parameter, but a fixed number.Comment: 2 pages, LaTeX 2e style articl

Limit on the electric charge-nonconserving μ+→invisible\mu^+ \to invisible decay

The first limit on the branching ratio of the electric charge-nonconserving invisible muon decay $Br(\mu^+ \to invisible) < 5.2 \times 10^{-3}$ is obtained from the recently reported results on new determination of the Fermi constant from muon decays. The results of a feasibility study of a new proposed experiment for a sensitive search for this decay mode at the level of a few parts in 10^{11} are presented. Constrains on the $\tau \to invisible$ decay rate are discussed. These leptonic charge-nonconserving processes may hold in four-dimensional world in models with infinite extra dimensions, thus making their searches complementary to collider experiments probing new physics.Comment: 5 pages, 2 Figure, to appear in PR

Interplay of gravitation and linear superposition of different mass eigenstates

The interplay of gravitation and the quantum-mechanical principle of linear superposition induces a new set of neutrino oscillation phases. These ensure that the flavor-oscillation clocks, inherent in the phenomenon of neutrino oscillations, redshift precisely as required by Einstein's theory of gravitation. The physical observability of these phases in the context of the solar neutrino anomaly, type-II supernovae, and certain atomic systems is briefly discussed

The decay eta_c^prime -> eta_c pi pi

It is pointed out that the decay of the recently observed charmonium eta_c^prime resonance, eta_c^prime -> eta_c pi pi is simply related to the well studied decay psi^prime -> J/psi pi pi and can thus be used for absolute normalization of other decay modes of the eta_c^prime. The total rate of the discussed decay should be approximately three to four times the corresponding rate for the psi^prime$ resonance making the channel with charged pions the most probable exclusive decay mode of the eta_c^prime with the branching ratio in the range 5-10 %.Comment: 5 pages, references adde

CP violation in unpolarized e^+ e^- to charginos at one loop level

We study CP violation in e^+ e^- to \tilde\chi_i^+\tilde\chi_j^- in the framework of the MSSM. Though the cross section of this process is CP-even at the tree level even for polarized electron-positron beams, we show that it contains a CP-odd part at the one loop order and there are CP-odd observables that can in principle be measured even using unpolarized electron-positron beams. The relevant diagram calculations are briefly discussed and the results of selected (box) diagram computations are shown.Comment: similar to Phys. Rev. D version, but corrected figs. 4, 5, 6 (factor four

Compensation of B-L charge of matter with relic sneutrinos

We consider massless gauge boson connected to B-L charge with and without compensation to complete the investigation of the gauging of B and L charges. Relic sneutrinos predicted by SUSY and composite models may compensate B-L charge of matter. As a consequence of the possible compensation mechanism we have shown that the available experimental data admit the range of the B-L interaction constant, 10^{-29} < {\alpha}_{B-L} < 10^{-12}, in addition to {\alpha}_{B-L} < 10^{-49} obtained without compensation.Comment: 6 page