Related papers: Fine-structure constant constraints on Bekenstein-…
We discuss how laboratory experiments can be used to place constraints on possible variations of the fine structure constant alpha in the observationally relevant redshift interval z ~= 0 - 5, within a rather general theoretical framework.…
We search for transient variations of the fine structure constant using data from a European network of fiber-linked optical atomic clocks. By searching for coherent variations in the recorded clock frequency comparisons across the network,…
An attempt is made for a new type of analysis of the time-variability of the fine-structure constant trying to fit the most recent result from the laboratory measurements, the Oklo constraint and the data from the QSO absorption lines all…
We forecast the ability of future CMB and galaxy lensing surveys to constrain variations of the fine structure constant. We found that lensing data, as those expected from satellite experiments as Euclid could improve the constraint from…
By measuring the fundamental constants in astrophysical objects one can test basic physical principles as space-time invariance of physical laws along with probing the applicability limits of the standard model of particle physics. The…
Assuming a Friedmann universe which evolves with a power-law scale factor, $a=t^{n}$, we analyse the phase space of the system of equations that describes a time-varying fine structure 'constant', $\alpha$, in the…
We study the change of the effective fine structure constant in the cosmological models of a scalar field with a non-vanishing coupling to the electromagnetic field. Combining cosmological data and terrestrial observations we place…
We explore the possibility that the reported time variation of the fine structure constant $\alpha$ is due to a coupling between electromagnetism and gravitation. This may reconcile the claimed results on $\alpha$ with the upper limit from…
Any variation of the fundamental physical constants, and more particularly of the fine structure constant, $\alpha$, or of the mass of the electron, $m_e$, would affect the recombination history of the Universe and cause an imprint on the…
A brief description of the main methods for determining the fine structure constant is given. It is shown that the exact value of the fine structure constant is important for the new International System of Units (SI) and for fundamental…
In present paper we evaluate the fine structure constant variation, that should take place as the Universe expands and its curvature is changed adiabatically. Such variation of the fine structure constant is attributed to an energy losses…
Using a gauge-invariant formalism we derive and solve the perturbed cosmological equations for the BSBM theory of varying fine structure 'constant'. We calculate the time evolution of inhomogeneous perturbations of the fine structure…
Recent updated results of quasar spectra suggested a 3.9$\sigma$ significance of spatial variation of the fine-structure constant. Theoretically, it is important to examine whether the fine-structure constant, as a fundamental constant in…
The constraints on the time variation of the fine structure constant at recombination epoch relative to its present value, $\Delta\alpha/\alpha \equiv (\alpha_{\mathrm{rec}} - \alpha_{\mathrm{now}})/\alpha_{\mathrm{now}}$, are obtained from…
The detection of a spatial variation of the fine-structure constant, alpha, based on study of quasar absorption systems has recently been reported. The physics that causes this alpha-variation should have other observable manifestations,…
The spectrograph ESPRESSO recently obtained a limit on the variation of the fine-structure constant, $\alpha$, through measurements along the line of sight of a bright quasar with a precision of $1.36$ ppm at $1\sigma$ level. This imposes…
We study the space-time evolution of the fine structure constant, $\alpha$, inside evolving spherical overdensities in a lambda-CDM Friedmann universe using the spherical infall model. We show that its value inside virialised regions will…
We examine the variation of the fine structure constant in the context of a two-field quintessence model. We find that, for solutions that lead to a transient late period of accelerated expansion, it is possible to fit the data arising from…
We discuss experiments and observations aimed at testing the possible space-time variability of fundamental physical constants, predicted by the modern theory. Specifically, we consider two of the dimensionless physical parameters which are…
Cosmography is a model-independent phenomenological approach to observational cosmology, relying on Taylor series expansions of physical quantities as a function of the cosmological redshift or other analogous variables. A recent work…