相关论文: Comment on time-variation of fundamental constants
We briefly review the recent experimental results on possible variations of the fine structure constant $\alpha$ on the cosmological time scale and its position dependence. We outline the theoretical grounds for the assumption that $\alpha$…
If the fine structure constant is not really constant, is this due to a variation of $e$, $\hbar$, or $c$? It is argued that the only reasonable conclusion is a variable speed of light.
It has been known that dimensional constants such as $\hbar$, $c$, $G$, $e$, and $k$ are merely human constructs whose values and units vary depending on the chosen system of measurement. Therefore, the time variation of dimensional…
Our conventional system of physical units is based on local or microscopic {\it dimensional} quantities which are {\it defined}, for convenience or otherwise aesthetic reasons, to be spacetime-independent. A more general choice of units may…
We derive formulae for the time variation of the gravitational ``constant'' and of the fine structure ``constant'' in various models with extra dimensions and analyze their consistency with the observational data.
We argue that models in which an observable variation of the fine structure constant is explained by motion of a cosmic scalar field, are not stable under renormalization, and require massive fine tuning that cannot be explained by any…
We show that observational limits on the possible time variation of constants of Nature are significantly affected by allowing for both space and time variation. Bekenstein's generalisation of Maxwell's equations to allow for cosmological…
Much work has been done after the possibility of a fine structure constant being time-varying. It has been taken as an indication of a time-varying speed of light. Here we prove that this is not the case. We prove that the speed of light…
Is the recent evidence for a time-varying fine structure 'constant' $\alpha$ to be interpreted as a varying $e$, $c$, $\hbar$, or a combination thereof? We consider the simplest varying electric charge and varying speed of light theories…
We review recent activity searching for variations in the fundamental constants of nature in quasar absorption spectra and in the laboratory. While research in this direction has been ongoing for many decades, the topic has recently been…
Several authors have recently explored the idea that physical constants such as c and G might vary over time and have formulated theories describing this variation that can address a range of cosmological problems. Such work typically…
We study the time variation of fundamental constants in the early Universe. Using data from primordial light nuclei abundances, CMB and the 2dFGRS power spectrum, we put constraints on the time variation of the fine structure constant…
In this paper we compare the dimensional method with the Lie groups tactic in order to show the limitations and advantages of each technique. For this purpose we study in detail a perfect fluid cosmological model with time-varying…
A variation of fundamental constants of physics is proposed in a frame of static universe. It is shown when the velocity of light increases (decreases) the Planck's constant increases (decreases) and mass of bodies decreases (increases).…
Fundamental constants are a cornerstone of the physical laws. Any constant varying in space and/or time would signal a violation of local position invariance and be associated with a violation of the universality of free fall, and hence of…
One of the topical problems of contemporary physics is a possible variability of the fundamental constants. Here we consider possible variability of two dimensionless constants which are most important for calculation of atomic and…
Tentative observations and theoretical considerations have recently led to renewed interest in models of fundamental physics in which certain ``constants'' vary in time. Assuming fixed black hole mass and the standard form of the…
This article describes the various experimental bounds on the variation of the fundamental constants of nature. After a discussion on the role of fundamental constants, of their definition and link with metrology, the various constraints on…
The laws of physics have a set of fundamental constants, and it is generally admitted that only dimensionless combinations of constants have physical significance. These combinations include the electromagnetic and gravitational fine…
The effect of fractal space time of the quantum particles on the variation of the fine structure constant $\alpha$ has been studied. The variation of fine structure constant has been investigated around De Broglie length $\lambda$ and…