abstract

The structure of a unified field theory is investigated in which the non symmetric “Ricci” tensor is expressed in terms of the most general variables with respect to which it is automatically Transposition Invariant in the sense of Einstein and Kaufman. It is shown that all such theories reduce to unified field theory proposed by the latter authors (E-K). Moreover, it is shown that this theory itself is fully equivalent to the theory of Einstein and Straus. Thus, unless one is prepared to complicate the Lagrangian unduly and arbitrarily, the latter appears. as the only non symmetric, four dimensional extension of General Relativity. Newly discovered symmetries of the theory give rise to a conservation law enabling an identification of the current vector density to be made.

abstract

The equations of motion of a test particle are derived from the field equations of Einstein’s unified field theory in the case when there is a cylindrically symmetric source. An exact form of the equations of motion, corresponding to a particular solution of the field equations is obtained.

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The hyperbolic metric principle is applied to study the bounds on \(K_{13}\)-decay form factors. Some of the results obtained in previous works are rederived and improved.

abstract

The experimental data on pion- and nucleon–nucleus interaction at energies considerably higher than 10 GeV are analysed on the basis of the intra-nuclear cascade model including a decrease in the number of intra-nuclear nucleons during the cascade development. Experiment and theory can be fitted at energies up to \(T\approx 100\) GeV within experimental accuracy. At higher energies the calculated multiplicity of shower particles noticeably exceeds the experimental values. The effects of many-particle interactions are discussed from this point of view.

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The inhomogeneous Dirac equation (depending on the potential of the external electromagnetic field) is transformed into a covariant Hamiltonian form similar to that obtained earlier for the free Dirac particle. The same procedure is extended to the case of the “amplified Dirac equation” containing additional tensor terms.

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Energy spectra of \(\alpha \) particles from the reaction \(^{115}\)In(p,\(\alpha \))\(^{112}\)Cd were measured at proton energy \(E_{\rm p} = 14\) MeV. A discussion of experimental results in the frame of current nuclear reaction models is given.

abstract

Photon production in \(\pi \)–Xe interaction at 9 GeV is analysed from the point of view of the description suggested previously. A strong correlation between transverse and longitudinal momenta of photons is observed similar to that in \(\pi \)–nucleon interactions.

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Following the general idea of a previous paper [5] the operations \(CP\) and \(T\) are defined in a rigorous manner by their actions on the one- and many- particle basis vectors describing free but physical (dressed) stable particles. It is shown that \(TCP\) invariance implies the possibility of a new redefinition of the inversion operators which restores the invariance under the full Poincaré group even in \(CP\) and \(T\) do not commute with the total Hamiltonian. The rigorous representatives of the space and time inversions have the forms \(ACP\) and \(AT\) respectively, where \(A\) is a suitable unitary operator.

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It is pointed out that the recent data on topological cross-sections in pp collisions indicate not only the presence of a diffractive component, but also strong correlations in the pionization process itself.

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Production of \(^6\)Li and \(^7\)Li fragments with \(E \gtrsim 10\) MeV/nucleon in the interactions of 25 GeV/\(c\) protons with heavy emulsion nuclei has been investigated. In particular, the influence of the fast fragment on the emission of the heavy product has been analysed.

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The paper discusses the relevance of ISR results concerning particle production for the fireball model. It is argued that there is no contradiction between the ISR data and cosmic ray data concerning the rapidity distribution. The evidence of cluster production is discussed.

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Observational and theoretical aspects of a possible presence of a neutrino background in the Universe are considered. Observable effects are related to the still open question of “missing mass” in clusters of galaxies. The presence of the neutrino sea can prove decisive in recognizing the proper structure of the space-time.

abstract

It is pointed out that if the mechanism of diffractive production of particles is the same as that of elastic scattering, the diffractive dissociation can be calculated as shadow of non-diffractive processes. A general method of calculation is proposed. It uses the technique of the overlap matrix. A specific calculation in Uncorrelated Jet Model is performed. In this calculation the diffractive processes arise as a direct consequence of correlations induced in non-diffractive interactions by energy and momentum conservation. The most important prediction of the model is that the inclusive mass distribution of diffractive dissociation splits into non-scaling part describing the low-mass excitations and the approximately scaling part describing the high-mass excitations. The non-scaling part of the mass spectrum is dominated by single particle production and at large masses behaves as \(d\sigma /d\mathcal {M}^2 \sim \mathcal {M}^{-6}\). The shape of the scaling part of the spectrum in the triple-Regge region is \(d\sigma /d \zeta = (\zeta \log \zeta )^{-1}\) where \(\zeta = \mathcal {M}^2/s\). The properties of exclusive diffractive channels are also discussed.