https://reports.sci.am/index.php/reports <p><em data-start="0" data-end="19">Reports of NAS RA</em> (REPNAS) is a peer‑reviewed, open‑access journal of the National Academy of Sciences of Armenia that publishes high‑quality research across all STEM disciplines.</p> <p>REPNAS welcomes Original Research Articles, Review Articles, Short Research Papers, Letters, and Editorials that deliver solid and sound contributions, robust methodologies, and multidisciplinary insights of relevance to the global scientific community.</p> "GITUTYUN" PUBLISHING HOUSE OF NAS RA en-US Reports of NAS RA 0321-1339 https://reports.sci.am/index.php/reports/article/view/9 <p>Within the general Gel’fand–Yaglom method, starting from the extended 28-component representation of the Lorentz group, we construct a new relativistic <em data-start="361" data-end="364">P</em>-invariant generalized equation for a spin-1/2 particle possessing three characteristics in addition to the electric charge. The model is first developed for a free particle, where the corresponding system of spinor equations is derived and then transformed into spin-tensor form. In this form, we incorporate the interaction with external electromagnetic fields. By eliminating the accessory variables of the complete wave function, we obtain a minimal four-component Dirac-like equation that contains three new interaction terms, interpreted as arising from the additional electromagnetic characteristics of the particle. This approach is further extended to a Riemann space–time background within the conventional tetrad formalism, leading to additional geometrical interaction terms involving the Ricci scalar R(x), the Ricci tensor Rαβ, and the Riemann curvature tensor Rαβρσ(x).</p> Vasiliy Kisel Elena Ovsiyuk Anton Bury Alina Ivashkevich Viktor Red'kov Artur Ishkhanyan Copyright (c) 2026 Vasiliy Kisel, Elena Ovsiyuk, Anton Bury, Alina Ivashkevich, Viktor Red'kov, Artur Ishkhanyan https://creativecommons.org/licenses/by-nc/4.0 2026-01-15 2026-01-15 126 1 1 1 10.54503/0321-1339-2026.126.1-1