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Alexia Auff\`eves and Philippe Grangier proposed to modify the quantum ontology by requiring that physical properties are attributed jointly to the system and to the context in which it is embedded. Comparing the formal structures of Quantum Theory and of Special Relativity may suggest a basis for such an interpretation of quantum theory., Comment: 11 pages, 3 figures

A paper by Harmut Traunm\"uller [1] showed from statistical studies of observational data that the most adequate equation to represent observations on magnitude and redshift from 892 type 1a supernovae is $\mu = 5\,log[(1+z)\,ln(1+z)] + const.$ Comparing the Hubble diagram calculated from the observed redshift data of 280 supernovae with Hubble diagrams inferred on the basis of two cosmological models in the range of z = 0.0104 to 8.1, Laszlo Marosi [2] found in a quite independant study that the best fit function to represent observations is $\mu= 44.109769 \,z^{0.059883}$. Noting that differences between the different cosmological models become more pronouced in a photon time-of-fligth $t_s$ vs. $z$ repr\'esentation, he also noted that the best equation to account for observations may also be written $z = -1+e^{2.024\,\,10^{-18} \,\,ts}$. In the light of these observational data, we compare the theoretical Hubble diagram obtained with the flat $\Lambda CDM$ model to the ones we have obtained few years ago [3, 4, 5] from a model that we call here the "light model" for the sake of clarity. Our conclusions are that values calculated on the basis of the $\Lambda CDM$ model exhibit poor agreement with the presently available data while the light model agrees exactly with observations and conclusions of statistical studies [1] and [2] (independently of the values of $\Omega_k$, $\Omega_M$ or $\Omega_{\Lambda}$). Our model giving no accelerating expansion of the universe, we conclude that this latter is not necessary and that models can exist which lead exactly to observations without having to consider any accelerating expansion of the universe. In an Appendix, we discuss some aspects of the model and we present a brief overview of some of its key results., Comment: 24 pages, 9 figures

We analyse the Bell paradox from the point of view of an inertial referential frame and from the one of an accelerated frame. We calculate the distance between the two accelerated spaceships as it appears in each referential and we show that neither of the two values represent the "real" length of the thread. Calculating this latter gives a clear understanding of the so-called paradox., Comment: 23 pages, 10 figures

In order to generalize the relativistic notion of boost to the case of non inertial particles and to general relativity, we come back to the definition of Lie group of Lorentz matrices and its Lie algebra and we study how this group acts on the Minskowski space. We thus define the notion of tangent boost along a worldline. This notion very general notion gives a useful tool both in special relativity (for non inertial particles or/and for non rectilinear coordinates) and in general relativity. We also introduce a matrix of the Lie algebra which, together with the tangent boost, gives the whole dynamical description of the considered system (acceleration and Thomas rotation). After studying the properties of Lie algebra matrices and of their reduced forms, we show that the Lie group of special Lorentz matrices has four one-parameter subgroups. These tools lead us to introduce the Thomas rotation in a quite general way. At the end of the paper, we present some examples using these tools and we consider the case of an electron rotating on a circular orbit around an atom nucleus. We then discuss the twin paradox and we show that when the one who made a journey into space in a high-speed rocket returns home he is not only younger than the twin who stayed on Earth but he is also disorientated because his gyroscope has turned with respect to earth referential frame., Comment: 30 pages, in English, 3 figure

A recent paper by Harmut Traunm\"uller shows that the most adequate equation to interpret the observations on magnitude and redshift from 892 type 1a supernovae would be mu = 5 log[(1+z) ln(1+z)] + const. We discuss this result which is exacly the one we have obtained few years ago when postulating a relation between the speed of light and the expansion of the universe. We also compare our analytical result to the conclusion of Marosi who studied 280 supernovae and gamma-ray bursts in the range 0.1014 < z < 8.1. The difference between his results and ours is at worst of 0.3 %., Comment: 7 pages, 1 figure

In a recent paper (Vigoureux et al. Int. J. Theor. Phys. 47:928, 2007) it has been suggested that the velocity of light and the expansion of the universe are two aspects of one single concept connecting space and time in the expanding universe. It has then be shown that solving Friedmann's equations with that interpretation (and keeping c = constant) can explain number of unnatural features of the standard cosmology (for example: the flatness problem, the problem of the observed uniformity in term of temperature and density of the cosmological background radiation, the small-scale inhomogeneity problem...) and leads to reconsider the Hubble diagram of distance moduli and redshifts as obtained from recent observations of type Ia supernovae without having to need an accelerating universe. In the present work we examine the problem of the cosmological constant. We show that our model can exactly generate $\Lambda$ (equation of state $P_\varphi = - \rho_\varphi c^2$ with $\Lambda \propto R^{-2}$) contrarily to the standard model which cannot generate it exactly. We also show how it can solve the so-called cosmic coincidence problem.

Recents works deal with the optical transmission on arrays of subwavelength holes in a metallic layer deposited on a dielectric substrate. Making the system as realistic as possible, we perform simulations to enlighten the experimental data. This paper proposes an investigation of the optical properties related to the transmission of such devices. Numerical simulations give theoretical results in good agreement with experiment and we observe that the transmission and reflection behaviour correspond to Fano's profile correlated with resonant response of the eigen modes coupled with nonhomogeneous diffraction orders. We thus conclude that the transmission properties observed could conceivably be explained as resulting from resonant Wood's anomalies., Comment: 7 pages, 10 figures, 2 tables