[en] An expectation value of the energy-momentum tensor for a massive scalar field propagating in a Robertson-Walker universe is calculated by taking account of both effects caused by the particle creation and the vacuum polarization. A special case of the Chitre-Hartle universe which enables us to perform an explicit calculation is also treated. (author)

[en] Detailed study of the structure in the rapidity plane allows to determine the amount of single and double diffraction within a cluster model. From semi-inclusive data on correlations the average number of particles due to decay of one cluster can be estimated

[en] We review the current understanding of the behaviour of inclusive cross sections at small x and large Q² in terms of Altarelli-Parisi evolution, the BFKL equation, and Regge theory, asking in particular to what extent they are mutually consistent. (author)

No abstract available

[en] Experimental and theoretical research on strong interactions is summarized. A list of publications is included. (U.S.)

[en] Experimental research on nuclear structure from the study of strong interactions at intermediate energies is summarized. A list of publications is included

No abstract available

[en] The scalar model for collapse of Langmuir waves in plasmas is studied numerically in two and three dimensions, for both radially symmetric and anisotropic initial conditions. Using a dynamic rescaling method, singular solutions are shown to become isotropic and self-similar near collapse. In two dimensions, the self-similar profile is not universal. In the limit where the mass of the wave tends to its minimal value for collapse, the solution approaches a subsonic regime different from the generic singularity of the nonlinear Schroedinger equation

[en] It is argued that the measurements of the dispersion of the multiplicity distribution in hadron-nucleus collisions favour the processes of particle production in a sequence of collisions of the incident hadron with target nucleons. On the other hand, generation of particles on groups of nucleons treated as single units leads to large discrepancies. (author)

[en] Since muonium atoms come into existence as a result of stopping energetic positive muons, it has been suggested that intraspur reactions (primarily with thermalized electrons or OH radicals, in water) are responsible for: (i) muonium formation, (ii) direct generation of a fraction of the muons in diamagnetic molecules, and (iii) the ''missing'' muon polarization. These postulates are examined in detail by adding scavengers which can preclude intraspur reactions without reacting with muonium. The results show convincingly that intraspur processes are insignificant in (i) and (ii). Furthermore, they could only be important in (iii) if a spin-exchange process occurred with a frequency which was much greater than the ordinary diffusion-limited encounter frequency. Rather than this ''spur model'', the data obtained are consistent with the ''hot model'', whereby hot muonium atoms form beyond the spurs of the muon track