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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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Cosmic matter-antimatter asymmetry and gravitational force

Cosmic matter-antimatter asymmetry due to the gravitational interaction alone is discussed, considering the gravitational coupling of fermion matter related to the Yang-Mills (1954) gauge symmetry with the unique generalization of the four-dimensional Poincare group. Attention is given to the case of weak static fields which determines the space-time metric where only large source terms are retained. In addition, considering lowest-order Feynman diagrams, there are presented gravitational potential energies between fermions, between antifermions, and between a fermion and an antifermion. It is concluded that the gravitational force between matter is different from that between antimatter; implications from this concerning the evolution of the universe are discussed.

Hsu, J. P.

Stopping powers and cross sections due to two-photon processes in relativistic nucleus-nucleus collisions

The effects of electromagnetic-production processes due to two-photon exchange in nucleus-nucleus collisions are discussed. Feynman diagrams for two-photon exchange are evaluated using quantum electrodynamics. The total cross section and stopping power for projectile and target nuclei of identical charge are found to be significant for heavy nuclei above a few GeV per nucleon-incident energy.

Cheung, Wang K.

Electromagnetic form factor of the neutrino.

Electromagnetic form factors of electron and muon neutrinos evaluated, using intermediate vector- boson theory, noting renormalization induced by electromagnetic interactions

PARTICLE THEORY