Related papers: The Proton Radius Puzzle
We have analyzed the proton form factor data by using a number of phenomenological parameterizations (models) and extracting the proton electric and magnetic radii. To this end we performed a global fit to all available form factor data,…
The Lamb shift in muonic hydrogen was measured some time ago to a high accuracy. The theoretical prediction of this value is very sensitive to the proton-finite-size effects. The proton radius extracted from muonic hydrogen is in…
The result of a recent measurement of the size of the proton [R. Pohl et al., Nature 466, 213] performed on the base of the muonic hydrogen spectroscopy turned out to be significantly different, by five standard deviations, from the results…
Parity violating electron scattering can measure the neutron density of a heavy nucleus accurately and model independently. This is because the weak charge of the neutron is much larger then that of the proton. The Parity Radius Experiment…
Alvarado, Aranda, and Bonilla propose a sub-GeV U(1)R gauge boson model to explain the proton charge radius discrepancy. Their model assumes opposite sign U(1)R charge assignments for up and down quarks in the nucleon. I point out that…
The Lamb shift measurement and theory are now both a dynamically developing field and we give a review of the current data. Critical comparison of theory and experiment can be done using a value of the proton charge radius and we pay…
We obtain a model independent expression for the muonic hydrogen Lamb shift up to $\mathcal O (m_\mu \alpha^6, m_\mu \alpha^5 \frac{m_\mu^2}{m_\rho^2})$. The hadronic effects are controlled by the chiral theory, which allows for their model…
By combining the constraints of charge symmetry with new chiral extrapolation techniques and recent low-mass quenched lattice QCD simulations of the individual quark contributions to the electric charge radii of the baryon octet, we obtain…
Lepton universality, meaning the equal coupling of the electroweak gauge bosons to the different lepton flavours, is a central property of the Standard Model (SM). Tests of lepton universality in ratios of rates of $b\to s\ell^+\ell^-$…
The mass radius is a fundamental property of the proton that so far has not been determined from experiment. Here we show that the mass radius of the proton can be rigorously defined through the formfactor of the trace of the…
The precise determination of the proton radius from recent elastic scattering electron-proton data is discussed. The necessary precision on the elastic cross section to discriminate among the values coming from atomic spectroscopy is…
The complex Kohn variational principle and the (correlated) hyperspherical harmonics method are applied to study the proton-deuteron elastic scattering at energies above the deuteron breakup threshold. Results for the elastic cross section…
The recent discovery of apparent cosmic acceleration has highlighted the depth of our ignorance of the fundamental properties of nature. It is commonly assumed that the explanation for acceleration must come from a new form of energy…
In this article we propose a new relativistic paradox concerning the absorption of a photon by a hydrogen atom. We show that the actual cause of the paradox is one of the hypotheses of Bohr model; therefore, in order to solve the paradox,…
Precise measurements of the lepton properties provide stringent tests of the Standard Model structure and accurate determinations of its parameters. We overview the present status of a few selected topics: lepton universality, QCD tests and…
We present a dispersion theoretical analysis of recent date from electron-proton scattering. This allows for a high-precision extraction of the electric and magnetic radius of the proton, $r_E = (0.839\pm 0.002{}^{+0.002}_{-0.003})$~fm and…
The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton's bound…
We study space-time noncommutativity applied to the hydrogen atom and the phenomenological aspects induced. We find that the noncommutative effects are similar to those obtained by considering the extended charged nature of the proton in…
Einstein, Podolsky and Rosen (EPR) pointed out that the quantum-mechanical description of "physical reality" implied an unphysical, instantaneous action between distant measurements. To avoid such an action at a distance, EPR concluded that…
Recent measurements of recoil polarization in elastic scattering have been used to extract the ratio of the electric to the magnetic proton form factors. These results disagree with Rosenbluth extractions from cross section measurements,…