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The theoretical ideas relevant for the physics of the disoriented chiral condensate (DCC) are reviewed.

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We work out the method for evaluating the QCD coupling constant at finite temperature \((T)\) by making use of the finite \(T\) renormalization group equation up to the one-loop order on the basis of the background field method with the imaginary time formalism. The background field method, which maintains the explicit gauge invariance, provides notorious simplifications since one has to calculate only the renormalization constant of the background field gluon propagator. The results for the evolution of the QCD coupling constant at finite \(T\) reproduce partially the ones obtained in the literature. We discuss, in particular, the origin of the discrepancies between different calculations, such as the choice of gauge, the break-down of Lorentz invariance, imaginary versus real time formalism and the applicability of the Ward identities at finite \(T\).

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We discuss how realistic is the possibility of the existence of supersymmetric particles with masses of order \(\mathcal {O} (M_Z)\).

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A new method for the experimental study of bin-bin correlations is proposed. It is shown that this method is able to reveal important additional information on bin-bin correlations, beyond that of factorial-correlator measurements.

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We apply the method of scaled factorial moments to the analysis of temporal variability of gamma-ray bursts. Using this method we are able to estimate for majority of long bursts their characteristic variability scale, which we call pulse duration time \(T_P\). This new scale is independent from burst duration time introduced earlier and for most bursts in our sample is of order of 1.5 s. We find also that the average \(T_P\) for a group of very bright bursts is a factor of 2 shorter than that of dim bursts. This seem to support the hypothesis on cosmological nature of gamma-ray burst sources.

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Azimuthal asymmetry of vector-meson production in single-transversely polarized proton–proton collisions \((p\!\uparrow \! p)\) is calculated in a model based on the string fragmentation. The string is spanned by a valence quark of the projectile scattered on the target. The asymmetry is generated only during fragmentation of the scattered quark into hadrons. The obtained asymmetry of the \(\rho \) mesons is opposite in sign to that of pions. On the other hand, if the asymmetry were generated during the quark scattering then the asymmetries of the vector and of the pseudoscalar mesons would be close to each other.

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The standard phenomenology of the soft pomeron in hadron–hadron interactions is recalled briefly. The model is confronted with the HERA data for the total photoproduction cross section, deep inelastic scattering, diffractive vector meson photoproduction and diffractive electroproduction of vector mesons. Although much of the data can be explained by the model, there are some aspects of the HERA data which require a more rapid variation with energy than can be incorporated. It is argued that the perturbative (BFKL) pomeron cannot give a sufficiently large contribution to explain these observations. Possible nonperturbative solutions to this problem are indicated.

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Top quark production in \(p \bar p\) and \(e^+e^-\) collisions is enhanced by the exchange of a Higgs boson. The enhancement factors are calculated in the threshold region using the Green function method.

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Erraticity analysis of multiparticle production data is introduced as a way of extracting the maximum amount of information on self-similar fluctuations. It is presented as the next logical step to take beyond the intermittency analysis. An erraticity spectrum \(e(\alpha )\) can be determined analogous to the multifractal spectrum \(f(\alpha )\). An analytical example is presented to elucidate the method of analysis and the type of results that can be obtained.

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Present interest for space oriented particle physics is reviewed with a survey of some highlights and of the European programmes under way. Fundamental physics in space, as it is in particular shaping up in Europe according to the ESA programme, is then presented with emphasis on the detection of gravitational waves. Expected signals are analysed in connection with the potentials of the detectors which are being built on the ground and now considered for space.

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We present a method of construction of a family of solutions of the Baxter equation arising in the Generalized Leading Logarithmic Approximation (GLLA) of the QCD pomeron. The details are given for the exchange of \(N=2\) reggeons but everything can be generalized in a straight-forward way to arbitrary \(N\). A specific choice of solutions is shown to reproduce the correct energy levels for half integral conformal weights. It is shown that the Baxter’s equation must be supplemented by an additional condition on the solution.

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The analogue of the loop–loop correlation function in \(2d\) gravity for the planar connected \(\phi ^3\) diagrams is calculated. It is shown that although the discretized formulas are different the scaling limit is the same as for the loop–loop correlation function. The derivation may serve as an alternative definition of the volume–volume correlator of Euclidean quantum gravity in \(2d\).

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Coupled channel formalism for unequal masses of interacting mesons has been developed using the separable interactions. The scattering amplitudes and the corresponding channel integrals have been calculated. A practical method to determine the potential parameters from the positions of resonances in the complex energy plane has been formulated. The two-channel formalism has been extended to three interacting channels. A useful parametrization of the \(3 \times 3\) \(S\)-matrix in terms of phase shifts and inelasticity parameters has been written.

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The arguments of statistical nature for the existence of constituents of active gravitational masses are presented. The present paper proposes a basis for microscopic theory of universal gravitation. Questions like the relation of cosmological constant and quantum theory, black hole radiance and the nature of inertia are addressed.

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Models of intermittent behaviour are usually formulated using a set of multiplicative random weights on a Cayley tree. However, intermittency in particle multiproduction from QCD jets is related to fragmentation of an additive quantum number, e.g. energy-momentum. We exhibit the non-trivial stochastic mapping between these additive and multiplicative cascading processes.

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A relativistic two-particle theory is used for the calculation of the lowest order correction to the electromagnetic binding and scattering of a pion by an atom. The binding energy is found to be equal to the result obtained with the Klein–Gordon equation. The relativistic correction to the differential cross section, however, differs from the corresponding Klein–Gordon result.

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The collinear QCD structure of the electron is studied within the Standard Model. The electron structure function is defined and calculated in leading logarithmic approximation. It shows important contribution from the interference of the intermediate electroweak bosons. The problem of momentum scales is extensively discussed. The master equations for the QCD parton densities inside the electron are constructed and solved numerically in the asymptotic region. Significant corrections to the naive evolution procedure are found. Phenomenological applications at present and future momentum scales are discussed.

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We estimate the damping parameter characterizing the rate of loss of coherence between the components of a state consisting of a coherent superposition of masses. In a medium at temperature \(T\) the result is \(D \approx T^3\) \((G\Delta M)^2\), where \(\Delta M\) is the mass spread and \(G\) the gravitational constant. Since each mass produces a different metric this may be viewed as a simple calculation of the decoherence rate between different metrics. In another application, we consider the loss of coherence of mixing neutrinos arriving from the early universe.

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We review ideas on a new type of measurements which are sensitive to the QCD vacuum color-magnetic fluctuations: correlations in the axial asymmetry of the hadronic final states and joint decay probabilities of the resonances produced in the high energy \(e^+e^-\) collisions.

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The masses of the yet undiscovered baryons containing single \(c\) or \(b\) quarks are estimated from the known masses using the following rules: equal distances in mass between the isomultiplets forming sextets, equal mass differences between the corresponding spin one-half baryons containing \(c\) and \(b\) quarks, hyperfine splittings inversely proportional to the masses of the heavy quarks.