abstract

The study of the process of particle creation in high-energy nucleon–nucleon and nucleus–nucleus collisions heavily relies on the pseudorapidity distribution (PD) of charged particles. Several theoretical theories and concepts may frequently be tested using the multiplicity distributions (MD) and PD of final-state particles. In this work, we have utilized PD to investigate potential processes that might produce the fast target protons (FTP) released from the interactions of \(^{84}\mathrm {Kr}\) with emulsion at 1 \(A\) GeV. In order to examine the properties of the FTP emitted system for various targets (such as AgBr, CNO, and Em) of the nuclear emulsion detector (NED), the angular distribution (AD) and PD of the generated FTP were examined.

abstract

In this article, we propose a unified framework for cosmological expansion and inflation at the level of background dynamics, by modeling both the inflaton field and dark energy as a four-dimensional continuous medium, whose elastic deformation is described by a covariant vector field. Focusing on homogeneous and isotropic background cosmology, we show that for a bulk modulus \(K = 1.64 \times 10^{109}~\mathrm {N}\,\mathrm {m}^{-2}\), the dark-energy density decreases by a factor of \(\sim 10^{122}\), while the scale factor expands \(10^{28}\) times over \(\sim 10^{-42}\) seconds during primordial inflation. For illustrative parameter values, our analysis suggests three potential new physical phenomena for future investigation, including longitudinal elastic modes, frequency redshifts in early-universe light, and improved fits to supernova curves. At the end of the paper, we discuss the challenges of applying the framework to inflationary perturbations, particularly the need for a consistent theory capable of producing a nearly scale-invariant power spectrum, as well as of addressing reheating, and identifying these as key directions for future work.