Related papers: Fast Light, Fast Neutrinos?
We discuss the kinematic limits for the process \nu_\mu \rightarrow \nu_\mu + e^+ + e^- in the assumption that neutrinos are superluminal. We derive our results by assuming that: i) it exists one reference frame in which energy and momentum…
The question of whether it is possible or not to surpass the speed of light is already centennial. The special theory of relativity took the existence of a speed limit as a principle, the light postulate, which has proven to be enormously…
The physics of the supernova may provide a clue of the cosmological dark matter. In the absence of new physics, the supernova calculations do not explain the observed velocities of pulsars. However, if there exists a singlet fermion with…
X-ray pulsars experiencing extreme mass accretion rates can produce neutrino emission in the MeV energy band. Neutrinos in these systems are emitted in close proximity to the stellar surface and subsequently undergo gravitational bending in…
We introduce neutrino astronomy from the observational fact that Nature accelerates protons and photons to energies in excess of 10^{20} and 10^{13} eV, respectively. Although the discovery of cosmic rays dates back close to a century, we…
The question is discussed of what is the speed of gravity (at the fundamental non-perturbative level). The question is important, if nowhere else, in discussing the problem of information "lost" in black holes. It turns out that the duly…
With a minimally modified dispersion relation for neutrinos, we reconsider the constraints on superluminal neutrino velocities from bremsstrahlung effects in the laboratory frame. Employing both the direct calculation approach and the…
Although special relativity limits the actual velocity of a particle to $c$, the velocity of light, the observed velocity need not be the same as the actual velocity as the observer is only aware of the position of a particle at the time in…
The existence of a faster-than-light particle is in direct opposition to Einstein's relativity and the principle of causality. However, we show that the theory of classical relativistic fields is not inherently inconsistent with the…
Superluminous supernovae are a new class of supernovae that were recognized about a decade ago. Both observational and theoretical progress has been significant in the last decade. In this review, we first briefly summarize the…
A new mechanism of electromagnetic radiation by electrons under the influence of a dense neutrino flux, termed "the spin light of electron" in neutrino flux ($SLe_\nu$), is considered. It is shown that in the case when electrons are moving…
Faster-than-light or superluminal motion was originally predicted as a relativistic illusion of ballistic moving ejecta, and confirmed in a few tens of sources observationally. However, the recent results of the long-term multi-epoch…
According to the theory of ether light propagates with constant speed c with respect to the absolute reference frame and with respect to any other reference frame the speed of light is covariant. According to the theory of special…
We show that the superluminal muon neutrinos in the recent OPERA experiment can exist theoretically. The refutation of the OPERA experiment from some theoretical arguments is not universally valid, but resulting from some implicit…
Two astrophysical puzzles, the origin of pulsar velocities and that of dark matter, may have a simultaneous explanation if there exists a sterile neutrino with a mass in the 1-20 keV range and a small mixing (of order 10^{-4}) with the…
An attempt is made to estimate the velocity $V_{\nu}$ of electron antineutrino by using a theory of nuclear reactions \cite{1}. To estimate it, the experimental values of absorption cross sections $\mathbf{\sigma}%…
Several experimental techniques are currently under development, to measure the expected tiny fluxes of highest energy neutrinos above 10**18 eV. Projects in different stages of realisation are discussed here, which are based on optical and…
We investigate the possibility of explaining the propagation of neutrinos measured by the OPERA experiment with $\delta v_\nu=(v_\nu-c_0)/c_0$, where $c_0$ is the speed of light in vacuum, using a bimetric relativity model. The geometry of…
Mugnai et al. have reported an experiment in which microwave packets appear to travel in air with a speed substantially greater than c. They calculate the group velocity of their packets and find that it agrees with their experimental…
A reasonably short antineutrino run using OPERA and/or MINOS may test J. Franklin's explanation of recently claimed $\nu_\mu$ superluminality.