We use big bang nucleosynthesis calculations and light element abundance data to constrain the relative variation of the deuteron binding energy since the Universe was a few minutes old, ␦QϭQ(BBN) ϪQ(present). Two approaches are used, first treating the baryon to photon ratio as a free parameter, but with the additional freedom of varying ␦Q, and second using the WMAP value of and solving only for ␦Q.Including varying Q yields a better fit to the observational data than imposing the present day value, rectifying the discrepancy between the 4 He abundance and the deuterium and 7 Li abundances, and yields good agreement with the independently determined WMAP . Using WMAP , the minimal deviation consistent with the data is significant at about the 4 level; ␦Q/QϭϪ0.019Ϯ0.005. If the primordial 4 He abundance lies towards the low end of values in the literature, this deviation is even larger and more statistically significant. Taking the light element abundance data at face value, our result may be interpreted as variation of the dimensionless ratio Xϭm s /⌳ QCD of the strange quark mass and strong scale: ␦X/Xϭ(1.1Ϯ0.3)ϫ10 Ϫ3 . These results provide a strong motivation for a more thorough exploration of the potential systematic errors in the light element abundance data.

We calculated the contribution of internal nucleon electric dipole moments to the Schiff moment of 199 Hg. The contribution of the proton electric dipole moment was obtained via core polarization effects that were treated in the framework of random phase approximation with effective residual forces. We derived a new upper bound |dp| < 5.4 × 10 −24 e·cm of the proton electric dipole moment.

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The ratio of the elastic e + p to e − p scattering cross sections has been measured precisely, allowing the determination of the two-photon exchange contribution to these processes. This neglected contribution is believed to be the cause of the discrepancy between the Rosenbluth and polarization transfer methods of measuring the proton electromagnetic form factors. The experiment was performed at the VEPP-3 storage ring at beam energies of 1.6 and 1.0 GeV and at lepton scattering angles between 15 • and 105 • . The data obtained show evidence of a significant two-photon exchange effect. The results are compared with several theoretical predictions.

Schiff moments were calculated for a set of nuclei with full account of core polarization effects. A finite range P and T violating weak nucleon-nucleon interaction has been used in the calculations. While in the absence of core polarization the Schiff moment depends on one combination of the weak interaction constants, in the presence of core polarization the Schiff moment depends on all three constants separately. The dominant contribution comes from isovector, ∆T = 1, part of the weak interaction. The effects of core polarization were found to have in general a large effect on the Schiff moments.

The Schiff moment of the 199 Hg nucleus was calculated using finite range P-and T-violating weak nucleon-nucleon interaction. Effects of the core polarization were considered in the framework of RPA with effective residual forces.

Nucleon-antinucleon optical potential, which explains the experimental data for the processes e + e − → pp and e + e − → pions near the threshold of pp pair production, is suggested. To obtain this potential we have used the available experimental data for pp scattering, pp pair production in e + e − annihilation, and the ratio of electromagnetic form factors of a proton in the timelike region. It turns out that final-state interaction via the optical potential allows one to reproduce the available experimental data with good accuracy. Our results for the cross sections of e + e − → 6π process near the threshold of pp pair production are in agreement with the recent experiments.