Using an explicit notation for units, it is argued that electromagnetic fields measured by means of a charge and the corresponding fields measured by a monopole, are different physical entities. This result is related to the persistent failure of the experimental quest for monopoles.

States with negative absolute pressure are investigated from thermodynamic viewpoint. It is found that negativity of pressure does not contradict Callen’s postulates, and the postulates cannot be extended in a natural way to rule out just these states. These states may be stable against small fluctuations. In nuclear physics, QCD and GUT, \(p \lt 0\) states are easy to interpret by thermodynamics.

Using an analogy to a well known soliton model of hadrons the existence of the quark sea appearing in deep inelastic lepton-hadron scattering is justified. Then using the existence of \(\left \lt \bar \psi \psi \right \gt \) condensate in QCD we insert in the QCD functional integral a Lorentz scalar field which describes the quark-anti-quark pairs, and produces a dynamical mass for quarks.

A sequence of equations numerated by \(N = 1\), 2, 3, \(\dots \) realizing the Dirac square-root procedure for spin \(0 \otimes 1 \otimes \dots \frac {1}{2}N(N\) even) or \(\frac {1}{2} \otimes \frac {3}{2} \otimes \dots \otimes \frac {1}{2}N(N\) odd), is further discussed. For \(N = 2\) the Dfrac-type form of Kähler equation is reproduced. The equation with \(N=3\) is conjectured to be physically distinguished, providing a model for fermion generations.

The angular distributions of showers in lab. and c.m. systems have been studied for various effective target thickness. Also the variation of particle number densities in lab. and c.m. systems has been given as a function of \(\bar \nu \). It is observed that the particle density decreases with effective target mass in the most forward region in laboratory system whereas it shows an increasing trend in the c.m. system. The results seem to agree with CTM type of pictures of interaction. Some results on variation of \(R_{\rm A}\) with in different \(\eta \)-intervals have also been presented.

A simple theory of the heavy-ion optical potential \(\cal {V}\), based on the local density approach and the frozen density model, is used to derive the energy dependent proximity approximation \(\cal {V}^{\rm P}\) for the complex potential \(\cal {V}\). Both \(\cal {V}\) and \(\cal {V}^{\rm P}\) are calculated, and the accuracy of the proximity approximation and of the scaling law implied by the approximation is tested.

Initial stages of the phase transition of the neutron matter into strange matter at zero temperature and finite pressure are considered. Bubble formation is calculated numerically for pressures typical for a neutron star interior. The critical bubble size decreases rapidly with pressure, reaching minimum at \(p \sim 20\) MeV/fm\(^3\).