The Pionic Deuterium and the Pion Tetrahedron Vacuum Polarization

A double-well potential model is proposed for the pionic deuterium that enables to calculate the energy split, the potential barrier height and estimate the pion tetrahedron edge length. We propose that pion tetrahedrons, πTd = ud~dũ, play a central role in the Yukawa interaction by enabling quark exchange reactions between protons and neutrons by tunneling through a potential barrier. A vacuum polarization Feynman diagram is proposed for the πTd having chains of fermion loops for the two valence quarks and anti-quarks connected by gluons. With a higher order vacuum polarization diagram, the d and u quark loops are interleaved and the chiral symmetry is broken dynamically. The proposed πTd vacuum polarization integral does not diverge in both the IR and UV limits and vanishes in the limit of an infinite pion tetrahedron condensate. We propose a new Delbruck scattering Feynman diagram that includes d and u quark and anti-quark interleaved loops. We further propose that conversion of gravitons to photons may occur via quark and anti-quark loops that describe the pion tetrahedrons dynamics in the vacuum and may also transfer gravitational waves.

Behavior of Vacuum Polarization of Gauge-Boson and Wavefunction Renormalization Factor of Fermion in Different Phases of QED3

We investigate the behavior of the vacuum polarization of the gauge-boson Ⅱ and the wave-function renormalization factor of the fermion A in QEDs, using the coupled Dyson-Schwinger equations for the gauge-boson and fermion propagator. Using several different ansatze for the fermion-gauge-boson vertex, we find that the wave-function renormalization factor .4 and especially the vacuum polarization Ⅱ have different behaviors in the dynamical chiral symmetry breaking phase and in the chiral symmetric phase and hence in the phenomenological applications of QED3 one should choose different forms of gauge-boson propagator for these two phases. We also find that when adopting a specific ansatze of the fermion-gauge-boson vertex （ansatze （3）） the vacuum polarization function equals its one-loop perturbative result in the chiral symmetric phase. This fact suggests that in QEDs the Wigner vacuum corresponds to the perturbative vacuum.

New results on the hadronic vacuum polarization contribution to the muon g-2

Results on the lowest-order hadronic vacuum polarization contribution to the muon magnetic anomaly are presented. They are based on the latest published experimental data used as input to the dispersion integral. Thus recent results on τ→υτππ^0 decays from Belle and on e^＋e^- annihilation to π^＋π^- from BABAR and KLOE are included. The new data, together with improved isospin-breaking corrections for τ decays, result into a much better consistency among the different results. A discrepancy between the Standard Model prediction and the direct g- 2 measurement is found at the level of 3σ.

Deflection of Light by the Sun as Refraction in the Gravity Polarized Vacuum

It is shown that the deflection of star light passing by the Sun, which is allegedly explainable only by general relativity, can be understood quantitatively as a quasi-classical effect of light refraction in the vacuum polarized by the Sun's gravitational field. The theory of the dielectric polarization of the vacuum proposed pre- viously is further developed for the corresponding effect of the polarization of the vacuum in a gravitational field. The resulting refractive index of the vacuum in the presence of a gravitational field gives for the deflection of light by the Sun an angle |0| = 1.77', which is in good agreement with the experimental observations and the result of general relativity. From the theory Presented, it can also be deduced that the velocity of a horizontal light beam at 1000 km above ground level of the Earth has a velocity deficit - c= 5.73 cm / s in comparison to the light velocity on the ground.

Interesting QFT Problems Tackled in New Fashion

The Dimensional Regularization technique of Bollini and Giambiagi (BG) [Phys. Lett. B 40, 566 (1972);Il Nuovo Cim. B 12, 20 (1972);Phys. Rev. D 53, 5761 (1996)] cannot be employed for all Schwartz Tempered Distributions Explicitly Lorentz Invariant (STDELI) S′L. We lifted such limitation in [J. Phys. Comm. 2 115029 (2018)], which opens new QFT possibilities, centering in the use of STDELI that allows one to obtain a product in a ring with zero divisors. This in turn, overcomes all problems regrading QFT infinities. We provide here three examples of the application of our STDELI-extension to quantum field theory (A) the exact evaluation of an electron’s self energy to one loop, (B) the exact evaluation of QED’s vacuum polarization, and C) the theory for six dimensions, that is non-renormalizable.

Analytic forms for cross sections of di-lepton production from e^+e^-collisions around the J/ψresonance

A detailed theoretical derivation of the cross sections of e^＋e^-→e^＋e^-and e^＋e^-→μ＋μ-around the J/ψ resonance is reported. The resonance and interference parts of the cross sections, related to J/ψ resonance parameters, are calculated. Higher-order corrections for vacuum polarization and initial-state radiation are considered. An arbitrary upper limit of radiative correction integration is involved. Full and simplified versions of analytic formulae are given with precision at the level of 0.1% and 0.2%, respectively. Moreover, the results obtained in the paper can be applied to the case of the ψ（3686） resonance.

Hadronic cross section of e^+e^- annihilation at bottomonium energy region

The Born cross section and dressed cross section of e+e−→bb¯and the total hadronic cross section in e+e−annihilation in the bottomonium energy region are calculated based on the Rb values measured by the BaBar and Belle experiments.The data are used to calculate the vacuum polarization factors in the bottomonium energy region,and to determine the resonant parameters of the vector bottomonium(-like)states Y(10750),Υ(5S),andΥ(6S).