Constraining Horava-Lifshitz gravity from neutrino speed experiments

We constrain Horava-Lifshitz gravity using the results of OPERA and ICARUS neutrino speed experiments, which show that neutrinos are luminal particles, examining the fermion propagation in the earth's gravitational field. In particular, investigating the Dirac equation in the spherical solutions of the theory, we find that the neutrinos feel an effective metric with respect to which they might propagate superluminally. Therefore, demanding not to have superluminal or subluminal motion we constrain the parameters of the theory. Although the excluded parameter regions are very narrow, we find that the detailed balance case lies in the excluded region.Comment: 5 pages, no figure, version published at Gen.Rel.Gra

Violent Crime in the United States of America: A Time-Series Analysis Between 1960-2000

This paper empirically assesses the effect of socio-economic and demographic variables on violent crime in the United States. Using national-level time-series data over the period 1960-2000, I estimate an unrestricted vector autoregressive (VAR) model individually for overall violent crime, murder, rape and assault. The results indicate that there is no long-run relationship among the examined variables, but a significant short-run relationship holds. Imprisonment growth, income inequality, alcohol consumption, and racial composition of the male youth population are shown to influence the short-run behaviour of violent crime.Violent Crime; Rationality; Socio-economic and Demographic Determinants; Cointegration Analysis; Dynamic OLS

Gravity's Rainbow: a bridge towards Horava-Lifshitz gravity

We investigate the connection between Gravity's Rainbow and Horava-Lifshitz gravity, since both theories incorporate a modification in the UltraViolet regime which improves their quantum behavior at the cost of the Lorentz invariance loss. In particular, extracting the Wheeler-De Witt equations of the two theories in the case of Friedmann-Lemaitre-Robertson-Walker and spherically symmetric geometries, we establish a correspondence that bridges them.Comment: 20 page

String in Horava-Lifshitz Gravity

We generalize recent analysis of the dynamics of point particle in Horava-Lifshitz background to the case of string probe when we replace the Hamiltonian constraint of the Polyakov string with the constraint that breaks Lorentz invariance of target space-time. Then we find corresponding Lagrangian and argue that the world-sheet theory is invariant under foliation preserving diffeomorphism. Finally we discuss the Hamiltonian dynamics and show that this is well defined on condition that the world-sheet lapse function obeys the projectability condition.Comment: 20 pages, references adde