دکتر یوسف یوسفی

In the Copenhagen interpretation of quantum mechanics, from the mathematical formalism of quantum theory used to the prediction of experiences, what is observable is real and beyond is not. Quantum theory is the end of the physics line, and any question that quantum mechanics can not answer, not researchable. Copenhagenists have differing views on the reality of quantum objects: some believed that there was no reality beyond phenomena, some believed that the atomic world was full of talents and abilities that could be actualized by measurement, and so on. But Einstein, Boehm, and their co-thinkers believe that we have something called the real state of a physically system that exists objectively, independent of any observation or measurement, and that can be described by physical concepts. Physical research means knowing this physical reality as it is, knowing the nature of objects independent of the human mind. They believe that nature can not be known only through experiments and experimental data, but we must go to the creative human mind and embed theoretical structures to obtain a representation of physical reality. But we must regularly modify these theoretical structures with the help of experience to get closer and closer to physical reality.

In this paper, temperature dependence of the magnetic susceptibility of the Mn12 magnetic molecular cluster is investigated in different fields. Until now, only dipole excitations were considered in calculations to calculate magnetic susceptibility, but due to the spin number of this molecular cluster and in order to obtain higher computational accuracy, more multipolar excitations should be included in the calculations. For this purpose, in this paper, in the calculations related to the magnetic susceptibility of the molecule, in addition to dipolar excitations, quadrupole excitations are also considered, and the relevant diagrams are drawn. Calculations show that the results obtained in a situation where quadrupole excitations are considered, are more consistent with the experimental results.

In this article, the teaching of basic science in the contemporary period of Iran with the past century, especially the scientific flourishing of Iran, which coincided with the Middle Ages in Europe and the West, was compared and the educational strengths and weaknesses of these two periods were expressed. The first weakness in the field of science is the conservation of the scientific knowledge of old Iranian scientists. The weaknesses of contemporary educational models, which include the style of education (modularism), mere specialization, the partial view of science, and the lack of attention to physical concepts. These weaknesses have reduced the acceptance of scholars and enthusiasts from basic sciences, especially physics. The lack of mutual understanding between the purpose and the lack of exchange of information between basic science scientists and engineers has slowed the progress of industry and technology in the country. In this paper, we present these weaknesses and present proposed solutions.

In this paper, we have studied the equations describing the proposed experimental Hamiltonian of a single-molecule magnet Fe8. In this research, we used from coherent states in real parameter and Fayman path integral. These nonlinear equations fully described dynamic of this single-molecule magnet in Su (2) and Su (3) groups. The solutions of these equations are magnetic solitons (not calculated in this study). »Linear equations show that for this SMM, the mean square torque ( Quadrupole excitation) is not constant and its dynamic consists of two parts. One part, rotate around the classical spin vector and the other is related to changing the size of the quadrupole torque. The spin wave dispersion equation for dipole and quadruple branches is calculated for small linear excitations from ground state (vacuum). These equations show that, for dipole branch, the spin wave is damping away from the single-molecular magnet and oscillating and not damping for the quadrupole branch.