Related papers: Early Universe Constraints on Time Variation of Fu…
In this thesis, we focus on the study of the variation of the electron mass $m_e$, and the fine structure constant $\alpha$, at different cosmic times. We analyze the details of the recombination physics, including helium recombination, in…
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…
Review of recent works devoted to the temporal and spatial variation of the fundamental constants and dependence of the fundamental constants on the gravitational potential (violation of local position invariance) is presented. We discuss…
The possibility of variations of the values of fundamental constants is a phenomenon predicted by a number of scenarios beyond General Relativity. This can happen if ``our'' fundamental constants are not the actual constants of the…
We study the role of fundamental constants in an updated recombination scenario. We focus on the time variation of the fine structure constant, and the electron mass in the early Universe, and put bounds on these quantities by using data…
We studied the role of fundamental constants in an updated recombination scenario, focusing on the time variation of the fine structure constant \alpha and the electron mass m_e in the early Universe. Using CMB data including WMAP 5-yr…
Astronomical observations have a unique ability to determine the laws of physics at distant times in the universe. They, therefore, have particular relevance in answering the basic question as to whether the laws of physics are invariant…
A time variation in the Higgs vacuum expectation value alters the electron mass and thereby changes the ionization history of the universe. This change produces a measurable imprint on the pattern of cosmic microwave background (CMB)…
We put limits on the time variation of the electron mass in the early universe using observational primordial abundances of D, He4 and Li7, recent data from the Cosmic Microwave Background and the 2dFGRS power spectrum. Furthermore, we use…
We study the cosmological constraints of the time variation of the electron mass $m_e$ and the fine-structure constant $\alpha$, using data of cosmic microwave background, supernovae light curve and baryon acoustic oscillation (BAO) data…
We update the constraints on the time variation of the fine structure constant $\alpha$ and the electron mass $m_e$, using the latest CMB data, including the 7-yr release of WMAP. We made statistical analyses of the variation of each one of…
We calculate bounds on the variation of the fine structure constant at the time of primordial nucleosynthesis and at the time of neutral hydrogen formation. We use these bounds and other bounds from the late universe to test Bekenstein…
We obtain constraints on the variation of the fundamental constants from the full shape of the redshift-space correlation function of a sample of luminous galaxies drawn from the Data Release 9 of the Baryonic Oscillations Spectroscopic…
I review recent constraints on and claimed detections of a time-varying fine-structure constant $\alpha$, and discuss our own work, particularly on the effects of $\alpha$ in the cosmic microwave background and large-scale structure. Our…
The observed constraints on the variability of the proton to electron mass ratio $\mu$ and the fine structure constant $\alpha$ are used to establish constraints on the variability of the Quantum Chromodynamic Scale and a combination of the…
Many physical theories beyond the Standard Model predict time variations of basic physics parameters. Direct measurement of the time variations of these parameters is very difficult or impossible to achieve. By contrast, measurements of…
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…
We discuss the fundamemtal constants in the Standard Model of particle physics, in particular possible changes of these constants on the cosmological time scale. The Grand Unification of the observed strong, electromagnetic and weak…
The formation of the cosmic microwave background radiation (CMBR) provides a very powerful probe of the early universe at the epoch of recombination. Specifically, it is possible to constrain the variation of fundamental physical constants…
We discuss present and future cosmological constraints on variations of the fine structure constant $\alpha$ induced by an early dark energy component having the simplest allowed (linear) coupling to electromagnetism. We find that current…