Related papers: Measuring the fine structure constant on white dwa…
We study the observed small deviations of high-redshift absorption spectra that are interpreted as a possible evidence for a variable fine structure constant. On the contrary, we claim that the effect could be completely attributed to the…
Measurements of the fine-structure constant alpha require methods from across subfields and are thus powerful tests of the consistency of theory and experiment in physics. Using the recoil frequency of cesium-133 atoms in a matter-wave…
We use the Cosmic Microwave Background (CMB) anisotropy data from Planck to constrain the spatial fluctuations of the fine-structure constant \alpha. Through Thompson scattering of CMB photons, spatial anisotropies of \alpha lead to…
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…
Theories that attempt to unify the four fundamental interactions and alternative theories of gravity predict time and/or spatial variation of the fundamental constants of nature. Different versions of these theories predict different…
We introduce a methodology to test models with spatial variations of the fine-structure constant $\alpha$, based on the calculation of the angular power spectrum of these measurements. This methodology enables comparisons of observations…
From the Sloan Digital Sky Survey (SDSS) Data Release 12, which covers the full Baryonic Oscillation Spectroscopic Survey (BOSS) footprint, we investigate the possible variation of the fine-structure constant over cosmological time-scales.…
The Single Ion Differential alpha Measurement (SIDAM) method for measuring fine stucture variations (daa)and its figures of merit are illustrated together with the results produced by means of FeII absorption lines of QSO intervening…
Murphy et al. (2003a, MNRAS, 345, 609) claim to find evidence of cosmological variations of the fine structure constant $\alpha$ in the spectra of intervening QSO absorption line systems. We find that this result is affected by systematic…
We use Bloch oscillations to transfer coherently many photon momenta to atoms. Then we can measure accurately the recoil velocity $\hbar k/m$ and deduce the fine structure constant $\alpha$. The velocity variation due to Bloch oscillations…
We consider several transitions between narrow lines that have an enhanced sensitivity to a possible variation of the fine structure constant, alpha. This enhancement may allow a search to be performed with an effective suppression of the…
The increased collecting area of the ELTs will bring fainter high-z targets within the reach of high-resolution ultra-stable spectrographs, thus enabling a new generation of precision consistency tests, including tests of the stability of…
In the present work, we consider the cosmological constant model $\Lambda\propto\alpha^{-6}$, which is well motivated from three independent approaches. As is well known, the hint of varying fine structure constant $\alpha$ was found in…
We investigate the constraints that OH microwave transitions in megamasers and molecular absorbers at cosmological distances may place on the evolution of the fine structure constant alpha=e^2/(hbar c). The centimeter OH transitions are a…
There are indications from the study of quasar absorption spectra that the fine structure constant $\alpha$ may have been measurably smaller for redshifts $z>2.$ Analyses of other data ($^{149}$Sm fission rate for the Oklo natural reactor,…
Stability and photometric accuracy of silicon imaging detectors are essential for the Habitable Worlds Observatory and a range of NASA missions that will explore time domain astrophysics and astronomy over a spectral range spanning soft…
The first step toward doing high-precision astrometry is the measurement of individual stars in individual images, a step that is fraught with dangers when the images are undersampled. The key to avoiding systematic positional error in…
The high resolution spectrograph ESPRESSO on the VLT allows measurements of fundamental constants at unprecedented precision and hence enables tests for spacetime variations predicted by some theories. In a series of recent papers, we…
We present a theoretical calculation on the time-variability of the fine-structure constant to fit the result of the recent precise analysis of the measurement of the QSO absorption lines. We find the parameters and initial values of the…
We have previously presented 5.7-sigma evidence for a smaller alpha at redshifts 0.2 < z_abs < 3.7 from a sample of 128 Keck/HIRES quasar absorption systems: da/a = (-0.57 +/- 0.10) x 10^{-5}. A non-zero da/a manifests itself as a distinct…