From the data release of OPERA - CNGS experiment, and publicly announced on 23 September 2011, we cast a phenomenological model based on a Majorana neutrino state carrying a fictitious imaginary mass term, already discussed by Majorana in 1932. This
mass term can be induced by the interaction with the matter of the Earths crust during the 735 Km travel. Within the experimental errors, we prove that the model fits with OPERA, MINOS and supernova SN1987a data. Possible violations to Lorentz invariance due to quantum gravity effects have been considered.
We analyze the effect of Proca mass and orbital angular momentum of photons imposed by a structured plasma in Kerr-Newman and Reissner-Nordstrom-de Sitter spacetimes. The presence of characteristic lengths in a turbulent plasma converts the virtual P
roca photon mass on orbital angular momentum, with the result of decreasing the virtual photon mass. The combination of this plasma effect and that of the gravitational field leads to a new astrophysical phenomenon that imprints a specific distribution of orbital angular momentum into different frequencies of the light emitted from the neighborhood of such a black hole. The determination of the orbital angular momentum spectrum of the radiation in different frequency bands leads to a complete characterization of the electrostatic and gravitational field of the black hole and of the plasma turbulence, with fundamental astrophysical and cosmological implications.
Context: Strings and other alternative theories describing the quantum properties of space-time suggest that space-time could present a foamy structure and also that, in certain cases, quantum gravity (QG) may manifest at energies much below the Plan
ck scale. One of the observable effects could be the degradation of the diffraction images of distant sources. Aims: We searched for this degradation effect, caused by QG fluctuations, in the light of the farthest quasars (QSOs) observed by the Hubble Space Telescope with the aim of setting new limits on the fluctuations of the space-time foam and QG models. Methods: We developed a software that estimates and compares the phase variation in the interference patterns of the high-redshift QSOs, taken from the snapshot survey of HST-SDSS, with those of stars that are expected to not be affected by QG effects. We used a two-parameter function to determine, for each test star and QSO, the maximum of the diffraction pattern and to calculate the Strehl ratio. Results: Our results go far beyond those already present in the literature. By adopting the most conservative approach where the correction terms, that describe the possibility for space-time fluctuations cumulating across long distances and partially compensate for the effects of the phase variations, are taken into account. We exclude the random walk model and most of the holographic models of the space-time foam. Without considering these correction terms, all the main QG scenarios are excluded. Finally, our results show the absence of any directional dependence of QG effects and the validity of the cosmological principle with an independent method; that is, viewed on a large scale, the properties of the Universe are the same for all observers, including the effects of space-time fluctuations.
183 -
Fabrizio Tamburini (Department of Astronomy University of Padova
, n Vicolo dellOsservatorio 3
, Padova
2009
We propose a thought experiment to detect low-energy Quantum Gravity phenomena using Quantum Optical Information Technologies. Gravitational field perturbations, such as gravitational waves and quantum gravity fluctuations, decohere the entangled pho
ton pairs, revealing the presence of gravitational field fluctuations including those more speculative sources such as compact extra dimensions and the sub-millimetric hypothetical low-energy quantum gravity phenomena and then set a limit for the decoherence of photon bunches and entangled pairs in space detectable with the current astronomical space technology.
We propose the use of heralded photons to detect Gravitational Waves (GWs). Heralded photons are those photons that, produced during a parametric downconversion process, are labelled by the detection and counting of coincidences of their correlated o
r entangled twins and therefore can be discriminated from the background noise, independently of the type of correlation/entanglement used in the setup. Without losing any generality, we illustrate our proposal with a gedankenexperiment, in which the presence of a gravitational wave causes a relative rotation of the reference frames associated to the double-slit and the test polarizer, respectively, of a Walborns quantum eraser cite{wal02}. In this thought experiment, the GW is revealed by the detection of heralded photons in the dark fringes of the recovered interference pattern by the quantum eraser. Other types of entanglement, such as momentum-space or energy-time, could be used to obtain heralded photons to be used in the future with high-frequency GW interferometric detectors when enough bright sources of correlated photons will be available.
We propose a thought technique for detecting Gravitational Waves using Einstein-Podolski-Rosen photon Entangled States. GWs decohere the entangled photon pairs, introduce a relative rotation and de-synchronize Alice and Bobs reference frames thus red
ucing the measured non-locality of correlated quanta described by Bells inequalities. Gravitational Waves, distorting quantum encryption key statistics away from a pure white noise, act then as shadow eavesdroppers. The deviation from the intrinsic white-noise randomness of a Quantum Key Distribution process can reveal the presence of a gravitational wave by analyzing the emerging color distortions in the key. Photon entangled states provide the key advantage of revealing the polarization rotation introduced by GWs without the need of previously fixed reference frames
