相关论文: Comments on redefinition of SI units based on fund…
Fixing the value of Avogadro's constant, the number of atoms in 12 grams of carbon-12, at exactly 84446886^3 would imply that one gram is the mass of exactly 18x14074481^3 carbon-12 atoms. This new definition of the gram, and thereby also…
The notion of ``fundamental constant'' is heavily theory-laden. A natural, fairly precise formulation is possible in the context of the standard model (here defined to include gravity). Some fundamental constants have profound geometric…
The contemporary practice is to favor the use of the SI units for electric circuits and the Gaussian CGS system for electromagnetic field. A modification of the Gaussian system of units (the Physics and Technology System) is suggested. In…
Discussion of the constancy, or otherwise, of the various so-called universal constants which abound in physics has continued for many years. However, relatively recent observations, which appear to indicate a variation in the value of the…
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…
Quantum electrodynamics is the first successful and still the most successful quantum field theory. Simple atoms, being essentially QED systems, allow highly accurate theoretical predictions. Because of their simple spectra, such atoms have…
A drawback of the new SI is that by fixing the value of the elementary charge $e$, the vacuum magnetic permeability $\mu_\circ$ and impedance $Z_\circ=\mu_\circ c$ are no longer fixed, but get written proportionately to $\alpha$. All…
A recent Letter proposed changing the dimensionless status of the radian and steradian within the SI, while allowing the continued use of the convention to set the angle 1 radian equal to the number 1 within equations, providing this is…
It is argued that the CODATA recommended values of the fundamental physical constants could not be used as the reference data in searching the hypothetical space-time variations of the fundamental physical constants. It is shown that the…
A brief overview is given on precision determinations of values of the fundamental physical constants and the search for their variation with time by means of precision spectroscopy in the optical domain.
The quest for the value of the electron's atomic mass has been subject of continuing efforts over the last decades. Among the seemingly fundamental constants which parameterize the Standard Model (SM) of physics and which are thus…
I argue that the laws of physics should be independent of one's choice of units or measuring apparatus. This is the case if they are framed in terms of dimensionless numbers such as the fine structure constant, alpha. For example, the…
Here we discuss direct links of the number of fundamental dimensions to the fundamental natural constants using simple arguments of dimensional analysis \corr{based on Maxwell's dimensions length (L), time (T) and mass (M) as well as the…
Review of recent works devoted to the variation of the fundamental constants is presented including atomic clocks, quasar absorption spectra, and Oklo natural nuclear reactor data. Assuming linear variation with time we can compare…
A quantum mechanical upper limit on the value of particle accelerations is consistent with the behavior of a class of superconductors and well known particle decay rates. It also sets limits on the mass of the Higgs boson and affects the…
The fine structure constant $\alpha $ includes the speed of light as given by $\alpha =\frac{e^{2}}{4\pi \epsilon_{0}c\hbar}$. It is shown here that, following a $TH\epsilon \mu $ formalism, interpreting the permittivity $\epsilon_{0}$ and…
The atomic transitions employed in the best of today's optical clocks are a strong foundation for the upcoming redefinition of the SI second. Including multiple transitions in the definition offers increased accuracy, a robust diversity of…
We study the properties of fundamental physical constants using the threefold classification of dimensional constants proposed by J.-M. L{\'e}vy-Leblond: constants of objects (masses, etc.), constants of phenomena (coupling constants), and…
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…
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…