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102 - Harald Fritzsch 2016
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 interactions impl ies relations between time variation of the finestructure constant alpha and the QCD scale $Lambda_c$. The astrophysical observation of a variation implies a time variation of $10^{-15} / year$. Several experiments in Quantum Optics, which were designed to look for a time variation of $Lambda_c$, are discussed.
220 - Harald Fritzsch 2015
In a composite model of the weak bosons the p-wave bosons are studied. The state with the lowest mass is identified with the boson, which has been observed at the LHC. Specific properties of the excited bosons are studied, in particular their decays into weak bosons and photons. Such decays might have been observed recently with the ATLAS detector at the Large Hadron Collider.
110 - Harald Fritzsch 2015
We discuss mass matrices with four texture zeros for the quarks and leptons. The three mixing angles for the quarks and leptons are functions of the fermion masses. The results agree with the experimental data. The ratio of the masses of the first tw o neutrinos is given by the solar mixing angle. The neutrino masses are calculated: $m_1$ $approx$ 0.004 eV, $m_2$ $approx$ 0.010 eV, $m_3$ $approx$ 0.070 eV.
148 - Harald Fritzsch 2015
We discuss the neutrino oscillations, using texture zero mass matrices for the leptons. The reactor mixing angle $theta^{}_{l}$ is calculated. The ratio of the masses of two neutrinos is determined by the solar mixing angle. We can calculate the mass es of the three neutrinos: $m_1$ $approx$ 0.003 eV - $m_2$ $approx$ 0.012 eV - $m_3$ $approx$ 0.048 eV.
150 - Harald Fritzsch , Joan Sola 2015
The idea that the vacuum energy density $rho_{Lambda}$ could be time dependent is a most reasonable one in the expanding Universe; in fact, much more reasonable than just a rigid cosmological constant for the entire cosmic history. Being $rho_{Lambda }=rho_{Lambda}(t)$ dynamical, it offers a possibility to tackle the cosmological constant problem in its various facets. Furthermore, for a long time (most prominently since Diracs first proposal on a time variable gravitational coupling) the possibility that the fundamental constants of Nature are slowly drifting with the cosmic expansion has been continuously investigated. In the last two decades, and specially in recent times, mounting experimental evidence attests that this could be the case. In this paper, we consider the possibility that these two groups of facts might be intimately connected, namely that the observed acceleration of the Universe and the possible time variation of the fundamental constants are two manifestations of the same underlying dynamics. We call it: the micro and macro connection, and on its basis we expect that the cosmological term in Einsteins equations, Newtons coupling and the masses of all the particles in the Universe, both the dark matter particles and the ordinary baryons and leptons, should all drift with the cosmic expansion. Here we discuss specific cosmological models realizing such possibility in a way that preserves the principle of covariance of General Relativity.
120 - Harald Fritzsch , Joan Sola 2012
In an expanding universe the vacuum energy density rho_{Lambda} is expected to be a dynamical quantity. In quantum field theory in curved space-time rho_{Lambda} should exhibit a slow evolution, determined by the expansion rate of the universe H. Rec ent measurements on the time variation of the fine structure constant and of the proton-electron mass ratio suggest that basic quantities of the Standard Model, such as the QCD scale parameter Lambda_{QCD}, may not be conserved in the course of the cosmological evolution. The masses of the nucleons m_N and of the atomic nuclei would also be affected. Matter is not conserved in such a universe. These measurements can be interpreted as a leakage of matter into vacuum or vice versa. We point out that the amount of leakage necessary to explain the measured value of dot{m}_N/m_N could be of the same order of magnitude as the observationally allowed value of dot{rho}_{Lambda}/rho_{Lambda}, with a possible contribution from the dark matter particles. The dark energy in our universe could be the dynamical vacuum energy in interaction with ordinary baryonic matter as well as with dark matter.
71 - Harald Fritzsch 2012
We study the hypothesis that weak bosons are composite systems, which have a size of the order of 10^{-17} cm. The electromagnetic selfenergies of the weak bosons lead to specific departures from the standard electroweak model, in agreement with obse rvation. Above the energy of 1 TeV the standard electroweak model breaks down completely.
In view of the latest T2K and MINOS neutrino oscillation data which hint at a relatively large theta_13, we perform a systematic study of the Majorana neutrino mass matrix M_nu with two independent texture zeros. We show that three neutrino masses (m _1, m_2, m_3) and three CP-violating phases (delta, rho, sigma) can fully be determined from two neutrino mass-squared differences (delta m^2, Delta m^2) and three flavor mixing angles (theta_12, theta_23, theta_13). We find that seven patterns of M_nu (i.e., A_{1,2}, B_{1,2,3,4} and C) are compatible with current experimental data at the 3-sigma level, but the parameter space of each pattern is more strictly constrained than before. We demonstrate that the texture zeros of M_nu are stable against the one-loop quantum corrections, and there exists a permutation symmetry between Patterns A_1 and A_2, B_1 and B_2 or B_3 and B_4. Phenomenological implications of M_nu on the neutrinoless double-beta decay and leptonic CP violation are discussed, and a realization of those texture zeros by means of the Z_n flavor symmetries is illustrated.
52 - Harald Fritzsch 2011
The weak bosons consist of two fermions, bound by a new confining gauge force. The mass scale of this new interaction is determined. At energies below 0.5 TeV the standard electroweak theory is valid. A neutral isoscalar weak boson X must exist - its mass is less than 1 TeV. It will decay mainly into quark and lepton pairs and into two or three weak bosons. Above the mass of 1 TeV one finds excitations of the weak bosons, which mainly decay into pairs of weak bosons. Leptons and quarks consist of a fermion and a scalar. Pairs of leptons and pairs of quarks form resonances at very high energy.
229 - Harald Fritzsch 2011
The texture zero mass matrices for the quarks and leptons describe very well the flavor mixing of the quarks and leptons. We can calculate the angles of the unitarity triangle. We expect the angle alpha of the unitarity triangle to be 90 degrees. The masses of the neutrinos can be calculated - they are very small, the largest neutrino mass is 0.05 eV. We calculated the matrix element of the mixing matrix, relevant for the reactor mixing angle. It can be measured in the near future in the DAYA BAY experiment.
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