Related papers: Explorations of two empirical formulae for fermion…
In 1981, Yoshio Koide noticed that the square root values of the charged lepton masses satisfy the relation \[ Q=\frac{m_e+m_{\mu}+m_{\tau}}{(\sqrt{m_e}+\sqrt{m_{\mu}}+\sqrt{m_{\tau}})^2} \approx \frac{2}{3} \] Inspired by this relation, we…
Based on the experimental data and estimations of the charged leptons and quarks masses, a close power law with exponent 3/4 has been found, connecting charged leptons masses and up quarks masses. A similar mass relation has been suggested…
We present a short historical and bibliographical review of the lepton mass formula of Yoshio Koide, as well as some speculations on its extensions to quark and neutrino masses, and its possible relations to more recent theoretical…
We investigate the masses of the light quarks with lattice QCD. We show that most of the large dependence on the lattice spacing, a, observed in previous determinations using Wilson fermions is removed with the use of an O(a) corrected…
We present new results for light quark masses. The calculations are performed using two flavours of $O(a)$ improved Wilson fermions. We have reached lattice spacings as small as $a \sim 0.07$fm and pion masses down to $m_{\pi} \sim 340$MeV…
We present the results of the recent high precision lattice calculation of the average up/down, strange and charm quark masses performed by ETMC with Nf=2 twisted mass Wilson fermions. The analysis includes data at four values of the…
We make a systematic theoretical analysis of the masses and their variation with energy by solving the renormalization group equation (RGE) in the Minimal Supersymmetric Standard Model (MSSM). The unification fermion masses of around 115…
The charged lepton masses obey to high precision the so-called Koide relation. We propose a generalization of this relation to quarks. It includes up and down quarks of the three generations and is numerically reasonably close to the Koide…
By designating one eigenvector of the mass matrix, one can reduce the free parameters in the mass matrix effectively. Applying this method to the quark mass matrix and to the lepton mass matrix, we find that this method is consistent with…
The two neutral kaon states in nature, the $K_L$ (long-lived) and $K_S$ (short-lived) mesons, are the two time-evolution eigenstates of the $K^0 - \overline{K^0}$ mixing system. The prediction of their mass difference $\Delta m_K$ based on…
In the framework of a mass formula proposed previously (transforming in a specific way three free parameters into three masses), a simple empirical sum rule for three charged-lepton masses is found, predicting m_\tau = 1776.9926 MeV, when…
In theories in which the parameters of the low energy theory are not unique, perhaps having different values in different domains of the universe as is possible in some inflationary models, the fermion masses would be distributed with…
We present two rather differently based predictions for the quark and lepton spectrum: One provides a rather successful fit to the mass suppressions---the well known fermion mass hierarchy---interpreted as due to most mass terms needing to…
A specific universal shape of empirical mass formula is proposed for all leptons $\nu_1, \nu_2, \nu_3$ and $e^-, \mu^-, \tau^- $ as well as all quarks $u, c, t$ and $d, s, b$ of three generations, parametrized by three free constants $ \mu,…
We present the results of a lattice QCD calculation of the average up-down and strange quark masses and of the light meson pseudoscalar decay constants with Nf=2 dynamical fermions. The simulation is carried out at a single value of the…
The charged fermion masses of the three generations exhibit the two strong hierarchies m_3 >> m_2 >> m_1. We assume that also neutrino masses satisfy m_{nu 3} > m_{nu 2} > m_{nu 1} and derive the consequences of the hierarchical spectra on…
We propose a left-right model of quarks and leptons based on the gauge group $SU(3)_C \times SU(2)_L \times SU(2)_R \times U(1)_{B-L}$, where the scalar sector consists of only two doublets: (1,2,1,1) and (1,1,2,1). As a result, any fermion…
We present results for the light, strange and charm quark masses using $N_f=2+1+1$ twisted mass fermion ensembles at three values of the lattice spacing, including two ensembles simulated with the physical value of the pion mass. The…
In this article, I will present the status of our calculation of the difference between the masses of the long- and short-lived neutral K mesons, $\Delta m_K$ predicted by the Standard Model. This calculation is performed on an ensemble of…
For the first time, we compute non-perturbatively, i.e. without lattice perturbation theory, the renormalization constants of two-fermion operators in the quenched approximation at $\beta=6.0$, 6.2 and 6.4 using the Wilson and the…