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A simple system of field-equations of the projective theory of relativity is solved for a homogeneous, isotropic cosmological model in the case of incoherent matter. The consequences of this projective cosmology are discussed and compared with those of the classical Einsteinian and projective Jordanian theories.

abstract

Die Konforminvarianz einer metrischen Feldtheorie mit einem zusätzlichen skalaren Feld wird auf Grund des dazugehörigen Variationsprinzipes untersucht. Die Überlegungen werden auf einige Beispiele —– insbesondere auf die Vakuumfeldgleichungen der vierdimensional formulierten projektiven Relativitätstheorie —– angewandt.

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Implications of Poincaré invariance in six-space are considered. It is shown that isospin space emerges in a natural way. The usual space-time is defined by electromagnetic interactions. The one meson exchange amplitude is naturally modified to have a sharp forward peak. The corresponding potential is derived.

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Dans cet article, nous démontrons qu’il est possible d’obtenir les théorèmes de Greenberg et Low, de Froissart, etc... dans une théorie des champs quantifiés, où le principe de causalité peut être modifié. Cela signifie que la vérifaction expérimentale de ces théorèmes peut ne nous donner au cune information sur la validité des principes fondamentaux à hautes énergies.

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By using the compensation field method we will show that it is possible that three intermediate vector bosons of the leptonic weak interaction with nonvanishing masses exist. These vector bosons are the compensation fields of the transformation of the Touschek type and of its generalization.

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The longitudinal polarization of electrons from the first forbidden \(\beta \) transitions in \(^{122}\)Sb, \(^{141}\)Ce, \(^{170}\)Tm, \(^{175}\)Yb, \(^{177}\) Lu isotopes was measured by Mott scattering. The results were compared with theoretical predictions based either on the shell model with spherical potential wave functions or on the Nilsson and Saxon–Woods wave functions. The value of the matrix elements ratio \(\langle i\alpha \rangle /\langle r\rangle \) was found to vary considerably depending on the isotope.

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Angular distributions of three neutron groups from the \(^{12}\)C(t,n)\(^{14}\)N reactions have been measured at 1.12, 1.26, 1375 and 1.68 MeV using the nuclear-emulsion method. A strong dependence of the shape of the angular distribution for then0 group on the triton energy was observed. The angular distributions of the n1 group are very similar to those of the \(^{12}\)C(t,p\(_0\)) reaction. A large maximum at backwards angles was found for the \(n_2\) group at 1.68 MeV.

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Measurable quantities, called generalized statistical tensors, which are functions of the reaction amplitudes, are introduced and investigated. Their role in the full experimental check of theoretical predictions between the amplitudes Is discussed. As an example the polarizations predict ions following from the additivity assumption in the quark model are investigated. It is shown that the full experimental check of the quark model predictions for the reaction \(\frac {1}{2}^++0^-\to \frac {3}{2}^++0^-\) cannot be made from knowledge of the angular distribution of the linear momenta of the decay products alone.

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The gamma-vibrational parameters \(B_{\gamma }\), \(C_\gamma \) and the energy \(E_\gamma \) of the gamma-vibrational state of the deformed nuclei are calculated as functions of the \(\varepsilon \)-deformation in the whole region between the equilibrium and the saddle point. Both the microscopic and macroscopic descriptions are used. The following result is obtained: when \(\varepsilon \) increases from its equilibrium value to the saddle point the nucleus begins to be more stiff with respect to the gamma vibration.

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The existence of the intermediate \(\delta \pi \) state in the decay \(D^0 \to \eta \pi \pi \) is discussed. It is shown that the reflection of the \(\omega \) production cannot produce a spurious maximum in the (\(\eta \pi \)) mass distribution at the position of the \(\delta \).

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The process of Coulomb decay in reactions between complex nuclei is studied. Investigations were made with account taken of the unadiabatic character of the collision, and also of the possibility of nucleus disintegration during the collision itself. The problems resulting from the consideration of this effect were also considered.

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The paper deals with the problem of the dynamic distortion of colliding particles in the near-barrier energy range conditioned by their Coulomb interaction. in contradistinction to the usually assumed condition of quasistatic collision, this work takes account of quantum effects and their effect on the height of the Coulomb barrier. There are also considerations concerning their role in exchange reactions.

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Some recent data on the \(\varrho ^0\) photoproduction on nuclei were analysed in terms of the Glauber model of multiple scattering in order to calculate the value of the rho-photon coupling constant. The numerical results depend on the assumed value \(\alpha _{\varrho N}\) of the ratio of the real to imaginary part of the elementary rho-nucleon scattering amplitude. For \(|\alpha _{\varrho N}| = 0.2\), which is a reasonable assumption, we get results consistent, within the limit of error, with the value of \(\gamma ^2_{\varrho }/4\pi = 1.0\), obtained at SLAC from the different analysis of the same data.

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The quark model is used to predict the joint decay distributions of pairs of strange baryons produced in the reactions \(\frac {1}{2}^+\frac {1}{2}^+\to \frac {1}{2}^+\frac {3}{2}^+\) with polarized target. For reactions with particles polarized perpendicularly to the reaction plane it is possible to make absolute predictions using data obtained from reactions with unpolarized particles. Relations between the statistical tensors provide a method of evaluating the additivity angle for the \(\frac {3}{2}^+\) isobar, if the polarization of the target in the reaction plane is not zero.

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We consider two invariant dynamical problems on the Minkowski plane: \(\delta \int L(\dot {u_1},\dot {u_2}, u_1-u_2)dv=0\) and \(\delta \int L(\dot {v_1}, \dot {v_2}, v_1-v_2)du=0\). We show that for an oscillatory motion, \(u\)-period and \(v\)-period in the first case are equal respectively to \(u\)-period and \(v\)-period in the second case, provided the total energy and momentum in both cases arc the same. We discuss also some general features of relativistic dynamical problems which are solvable by means of ordinary differential equations.

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The levels in \(^{73}\)As from the decay of 41 mm \(^{73m}\)Se were investigated. The conversion electron spectra in the energy region 20–4200 keV and gamma spectra were measured. The conversion coefficients and multipolarities of 12 transitions were determined. Obtained level structure of \(^{73}\)As is compared with data of the adjacent As isotopes and with recent theoretical calculations.

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Spectra of gamma radiation and internal conversion electrons from several germanium targets bombarded with 2.9 MeV protons were measured. Eleven transitions between \(^{76}\)As states excited in the \(^{76}\)Ge(\(p,n\))\(^{76}\)As reaction were identified. The energies of these states were found to be 45.5, 87, 121, 166, 265, 302, 377, 515 and 550 keV. The possible values of spin of the 87 and 121 keV levels have been confined to 1\(^+\), 2\(^+\) and 3\(^+\).

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Single pion production processes \(\pi ^-p\to n\varrho ^0\), \(pp \to n{\mit \Delta }^{++}\) are investigated using a Reggeized one-pion exchange amplitude suggested by the generalized Veneziano model. A good description of the experimental momentum transfer (\(t\)) distributions for \(|t| \lt 1\) GeV\(^2\) and laboratory momentum between 1.6 GeV/\(c\) and 10 GeV/\(c\) is found with only one normalizing parameter fitted to the data for each process.

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The experimental results of the \(^{52}\)Cr(\(^3\)He,\(p)^{54}\)Mn, \(^{53}\)Cr(\(^3\)He,\(d)^{54}\)Mn reactions, performed at \(E(^3\)He) = 18 MeV, and the results of the \(^{56}\)Fe(\(d,\alpha )^{54}\)Mn reaction, performed at \(E(d)\) = 12 MeV, are presented. The experimental data are analyzed in the frame work of the D.W.B.A. theory. The main conclusion of this study is that the configuration mixing is important, even in the \(^{54}\)Mn low lying state wave functions.

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The decay of \({151}\)Tb have been investigated. The spectra of gamma rays, gamma–gamma coincidences, conversion electrons spectra and electron–electron coincidences were measured. The level scheme of \(^{151}\)Gd populated from the decay of \(^{151}\)Tb is proposed.

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The elastic processes \(pp\), \(\overline {p}p\), \(\pi ^{\pm }p\), and \(K^{\pm }p\) are investigated in terms of a model with Regge poles and cuts generated by multiple scattering. The Born term consists of the Pomeron and degenerate meson trajectories contributions. Predictions of the model are in reasonable agreement with the experimental data for total cross-sections and the slope parameter of elastic differential cross-sections in the energy range from 10 to 70 GeV. The slope of Pomeranchuk trajectory is found to be 0.4 (GeV/\(c\))\(^{-2}\). Some difficulties of the present form of the model connected with antishrinkage phenomenon and the shape of Re\(F\)/Im\(F\) in the forward direction are discussed. Some predictions are given about the asymptotic values of total cross-sections and their behaviour in the high energy region.

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In the \(^{228}\)Pa \(\to \ ^{228}\)Th decay selected parts of the conversion electron spectrum were measured in order to clear up the discrepancies between the data on \(\gamma \)-transition energies.

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A quantum Markovian process within a set of states labelled by continuous and discrete parameters is constructed. While the scheme is a general one, special attention is paid to a process in Euclidean three-dimensional space which corresponds to a single nonrelativistic particle with internal degrees of freedom, e.g., spin.

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Examples of non-polynomial Lagrangians are investigated. Particularly interesting is a Lagrangian similar to that in the non-linear electrodynamics of Born and Infeld bitt for the simple case of a scalar field. Quantisation is feasible but the principle of superposition is invalidated. Nevertheless, a probabilistic interpretation is still possible.

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Using the additive quark model, the relations between statistical tensors for single and joint decay angular distributions in reactions \(0^-\frac {1}{2} ^+ \to 0^+\frac {3}{2}^+\), \(0^-\frac {1}{2} ^+ \to 1^+\frac {3}{2}^+\) and \(0^-\frac {1}{2} ^+\to 2^+ \frac {3}{2}^+\) are derived.

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In the case of \(^{58}\)Ni the matrix elements of the effective interaction of the last two nucleons are calculated using Migdal’s method and compared with those given by Kuo and empirical values determined by Auerbach.

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The paper deals with the process of complete fusion of nuclei in the face of the newest experimental data. The features stemming from the model assumed by the authors are scrutinized. It was shown that knowledge about the process of compound-nucleus formation may provide some conclusions regarding their “macroscopic” characteristics and also the magnitude of the fission barrier under conditions of extreme “heating”.

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The quark model with additive baryon exchange is applied to reactions of the type \(0^-+1/2^+\to 0^-+1/2^+\) and \(0^-+1/2^+\to 0^-+3/2^+\). The predictions for measurable quantities are given.