Modern Physics Letters A

I give a brief introduction to many worlds or "no wave function collapse" quantum mechanics, suitable for non-specialists. I then discuss the origin of probability in such formulations, distinguishing between objective and subjective notions of probability.

The OPERA collaboration recently reported that the muon neutrinos could be superluminal. More recently, Cohen and Glashow pointed that such superluminal neutrinos would be suppressed since they lose their energies rapidly via bremsstrahlung. Here, we propose that the Finslerian nature of the spacetime could account for the superluminal phenomena of particles. The Finsler spacetime permits the existence of the superluminal behavior of particles while the causality still holds. A new dispersion relation is obtained in a class of Finsler spacetimes. It is shown that the superluminal speed is linearly dependent on the energy per unit mass of the particle. We find that such a superluminal speed formula is consistent with the data of the OPERA, MINOS and Fermilab-1979 neutrino experiments as well as the observations on the neutrinos from the SN1987A.

It is shown that in the background of the Ayòn–Beato–Garcìa–Bronnikov (ABGB) black hole, the center-of-mass (CM) energy of collision for two charged particles falling freely from rest at infinity is infinite at the event horizon if one of the colliding particle has critical charge and the other one has any different value of the charge. For the Einstein–Maxwell-dilaton–axion (EMDA) black hole it is found that the CM energy of collision for two uncharged particles falling freely from rest at infinity remains finite. In the case of Bañados–Teitelboim–Zanelli (BTZ) black hole the CM energy of collision for two uncharged particles falling freely from rest at infinity is infinite at the event horizon if there is no rotation. It is observed that in the case of the extremal rotating BTZ black hole, at the event horizon this CM energy remains finite.

It is shown that the canonical formulation of the Abelian BF theory in D = 3 allows to obtain topological invariants associated to curves and points in the plane. The method consists on finding the Hamiltonian on-shell of the theory coupled to external sources with support on curves and points in the spatial plane. We explicitly calculate a nontrivial invariant that could be seen as a "projection" of the Milnor's link invariant , and as such, it measures the entanglement of generalized (or projected) Borromeans Rings in the Euclidean plane.

We discuss the dynamical effects of bulk viscosity and particle creation on the early evolution of the Friedmann–Robertson–Walker model in the framework of open thermodynamical systems. We consider bulk viscosity and particle creation as separate irreversible processes. Exact solutions of the Einstein field equations are obtained by using the "gamma-law" equation of state p = (γ-1)ρ, where the adiabatic parameter γ varies with scale factor of the metric. We consider the cosmological model to study the early phases of the evolution of the universe as it goes from an inflationary phase to a radiation-dominated era in the presence of bulk viscosity and particle creation. Analytical solutions are obtained for particle number density and entropy for all models. It is found that, by choosing appropriate functions for particle creation rate and bulk viscous coefficient, the models exhibit singular and non-singular beginnings.

We work out the impact that the recently determined time-dependent component of the Pioneer Anomaly (PA), if interpreted as an additional exotic acceleration of gravitational origin with respect to the well-known PA-like constant one, may have on the orbital motions of some planets of the solar system. By assuming that it points towards the Sun, it turns out that both the semi-major axis a and the eccentricity e of the orbit of a test particle would experience secular variations. For Saturn and Uranus, for which modern data records cover at least one full orbital revolution, such predicted anomalies are up to 2–3 orders of magnitude larger than the present-day accuracies in empirical determinations of their orbital parameters from the usual orbit determination procedures in which the PA was not modeled. Given the predicted huge sizes of such hypothetical signatures, it is unlikely that their absence from the presently available processed data can be attributable to an "absorption" for them in the estimated parameters caused by the fact that they were not explicitly modeled. The magnitude of a constant PA-type acceleration at 9.5 au cannot be larger than 9×10^-15 m s^-2 according to the latest observational results for the perihelion precession of Saturn.

We solve the gaugino Dirac equation on a smeared intersecting five-brane solution in E₈×E₈ heterotic string theory to search for localized chiral zero modes on the intersection. The background is chosen to depend on the full two-dimensional overall transverse coordinates to the branes. Under some appropriate boundary conditions, we compute the complete spectrum of zero modes to find that, among infinite towers of Fourier modes, there exist only three localized normalizable zero modes, one of which has opposite chirality to the other two. This agrees with the result previously obtained in the domain-wall type solution, supporting the claim that there exists one net chiral zero mode localized on the heterotic five-brane system.

This is a continuation of recent studies of ϒ(nS) production at the LHC in pp collisions. Our previous studies were for 2.76 TeV, while the present predictions are for 7.0 TeV collisions.

Beams of neutrinos have been proposed as a vehicle for communications under unusual circumstances, such as direct point-to-point global communication, communication with submarines, secure communications and interstellar communication. We report on the performance of a low-rate communications link established using the NuMI beam line and the MINERvA detector at Fermilab. The link achieved a decoded data rate of 0.1 bits/sec with a bit error rate of 1% over a distance of 1.035 km, including 240 m of earth.