Symmetries in elementary particles

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EIGENVALUES, EIGENVECTORS AND THE CONJUGACY CLASSES OF THE PSEUDO-ORTHOGONAL GROUPS O(n,m)

The eigenvalues, eigenvectors and the properties of the rotation part of the orthogonal group O(3) are well-known. What can we say about the eigenval- ues and eigenvectors of the Pseudo-orthogonal group O(2,1)? The answer to this question will be presented in this paper. Generalizations of the results for these groups in higher dimensions will also be discussed. The distinction between even and odd dimensions will be emphasized

A quantitative study of the impact of organizational culture, communication management, and clarity in project scope on constructions’ project success with moderating role of project manager’s competencies to enhance constructions management practices

The construction industry is considered a driver of economic growth, especially in developing countries. However, the successful completion of construction projects is a major challenge, due to the lack of competencies. The current study explores the effects of communication management practices, clarity in the scope of the construction project, and organizational culture to enhance project success. A project manager is essential in running a project smoothly and according to the schedule. Keeping in view the predominant role of the project manager, this study aims to find the moderating impact of manager competencies to improve the construction project routine and generate successful projects. A questionnaire survey was conducted to collect the data and determine how these variables influence construction project progress. The current research results show an ex-cellent association between a construction project’s success and the discussed independent variables. Additionally, it was found that a competent project manager can play a better role in preventing the uncomfortable influences of independent variables on the dependent variable. The obtained outcomes highlight the importance of adequately handling organizational culture, communication management, and clarity to achieve project success. These outcomes are helpful for the professionals working in the construction sector to raise the project success rate and enhance their construction management capabilities

Interacting Modified Variable Chaplygin Gas in Non-flat Universe

A unified model of dark energy and matter is presented using the modified variable Chaplygin gas for interacting dark energy in a non-flat universe. The two entities interact with each other non-gravitationally which involves a coupling constant. Due to dynamic interaction, the variation in this constant arises that henceforth changes the equations of state of these quantities. We have derived the effective equations of state corresponding to matter and dark energy in this interacting model. Moreover, the case of phantom energy is deduced by putting constraints on the parameters involved.Comment: 9 pages; Accepted for publication in European Physical Journal

Constraints on coupling constant between dark energy and dark matter

We have investigated constraints on the coupling between dark matter and the interacting Chaplygin gas. Our results indicate that the coupling constant $c$ between these two entities can take arbitrary values, which can be either positive or negative, thus giving arbitrary freedom to the inter-conversion between Chaplygin gas and dark matter. Thus our results indicate that the restriction $0<c<1$ on the coupling constant occurs as a very special case. Our analysis also supports the existence of phantom energy under certain conditions on the coupling constant.Comment: 16 Pages, 3 figure

Generalized Holographic Dark Energy Model

In this paper, the model of holographic Chaplygin gas has been extended to two general cases: first is the case of modified variable Chaplygin gas and secondly of the viscous generalized Chaplygin gas. The dynamics of the model are expressed by the use of scalar fields and the scalar potentials.Comment: 12 pages, to appear in Eur. Phys. J.