No Arabic abstract
A new causal paradox in superluminal signaling is presented. In contrast to the Tolman paradox with tachyon exchange between two parties, the new paradox appears already in a one-way superluminal signaling, even without creating the time loop. This produces a universal ban on superluminal signals, which is stronger than the ban imposed by the Tolman paradox. The analysis also shows that records of evolution of a superluminal object observed from two different reference frames may be time-reversed with respect to each other. Interactions with such objects could add some new features to spectroscopy. Even though relativity embraces superluminal motions, thus making the world symmetric with respect to the invariant speed barrier, their ineptness for signaling makes the symmetry incomplete. Key words: superluminal signaling, tachyons, the Tolman paradox
While the OPERA experimental scrutiny is ongoing in the community, in the present article we construct a toy model of {it extended Lorentz code} (ELC) of the uniform motion, which will be a well established consistent and unique theoretical framework to explain the apparent violations of the standard Lorentz code (SLC), the possible manifestations of which arise in a similar way in all particle sectors. We argue that in the ELC-framework the propagation of the superluminal particle, which implies the modified dispersion relation, could be consistent with causality. Furthermore, in this framework, we give a justification of forbiddance of Vavilov-Cherenkov (VC)-radiation/or analog processes in vacuum. To be consistent with the SN1987A and OPERA data, we identify the neutrinos from SN1987A and the light as so-called {it 1-th type} particles carrying the {it individual Lorentz motion code} with the velocity of light $c_{1}equiv c$ in vacuum as maximum attainable velocity for all the 1-th type particles. Thereby, we treat superluminal muon neutrinos as so-called {it 2-nd type} particles carrying the individual Lorentz motion code with the velocity $c_{2}$ as maximum attainable velocity for all the 2-nd type particles. For the muon neutrinos mean energy $E_{ u 2}=17.5$ GeV, claimed velocity $(v_{ u 2}-c)/c= 2.48times 10^{-5}$, and expected finite rest mass $m_{0}approx 1eV/c^{2}$, we obtain then $ c_{2}/capprox 17.5times 10^{9}$.
Superluminal tunneling of light through a barrier has attracted broad interest in the last several decades. Despite the observation of such phenomena in various systems, it has been under intensive debate whether the transmitted light truly carry the information of the original pulse. Here we report observation of anomalous time response for terahertz electromagnetic pulses passing through thin metal films, with the pulse shape of the transmitted beam faithfully resembling that of the incident beam. A causal theoretical analysis is developed to explain the experiments, though the theory of Special Relativity may confront a challenge in this exceptional circumstance. These findings may facilitate future applications in high-speed optical communication or signal transmission, and may reshape our fundamental understanding about the tunneling of light.
Some arguments in favour of the existence of tachyons and extensions of the Lorentz Group are presented. On the former, it is observed that with a slight modification to standard electromagnetic theory a single superluminal charge will bind to itself in a self-sustaining circular orbit, suggestive of a (modified) electromagnetic interpretation of the strong force. Symmetries in that theory are used in the subsequent analysis as a starting point in the search for physically-motivated extensions of the Lorentz Group. There is some discussion of the validity of imaginary coordinates in superluminal transformations of frame. The article concludes with some speculation on the implications for faster-than light travel.
In this work we consider a possible conceptual similarity between recent, amazing OPERA experiment of the superluminal propagation of neutrino and experiment of the gain-assisted superluminal light propagation realized about ten years ago. Last experiment refers on the propagation of the light, precisely laser pulse through a medium, precisely caesium atomic gas, with characteristic anomalous dispersion and corresponding negative group-velocity index with very large amplitude between two closely spaced gain lines (that is in some way similar to quantum theory of the ferromagnetism). It implies superluminal propagation of the light through this medium. Nevertheless all this, at it has been pointed out by authors, is not at odds with causality or special relativity, since it simply represents a direct consequence of the classical interference between ... different frequency components. We suggest that OPERA experiment can be in some way conceptually similar to the gain-assisted superluminal light propagation experiment. For this reason we suppose too that OPERA experiment can be simply explained in full agreement with causality and special relativity if there is some medium, precisely a scalar field (e.g. dark matter field, Higgs field or similar) through which neutrino propagates. We prove that, according to OPERA experiment data, supposed medium must be non-dispersive while its refractive index must be positive, smaller but relatively close to 1 (that is in some way similar to quantum theory of the diamagnetism). If it is true OPERA experiment results do not mean that special theory of relativity is broken, but they mean detection of suggested medium, i.e. a scalar field (e.g. dark matter field, Higgs field or similar).
Random numbers are an important resource for applications such as numerical simulation and secure communication. However, it is difficult to certify whether a physical random number generator is truly unpredictable. Here, we exploit the phenomenon of quantum nonlocality in a loophole-free photonic Bell test experiment for the generation of randomness that cannot be predicted within any physical theory that allows one to make independent measurement choices and prohibits superluminal signaling. To certify and quantify the randomness, we describe a new protocol that performs well in an experimental regime characterized by low violation of Bell inequalities. Applying an extractor function to our data, we obtained 256 new random bits, uniform to within 0.001.