Open Access Original Research Article

Evolution of Lovelock Tensor as a Generalized Einstein Tensor and Lovelock Gravity under Ricci Flow

S. Kumar, K.C. Petwal

Physical Science International Journal, Page 1-15

The higher dimensional gravity theory of Lovelock is a fascinating generalization of Einstein’s gravity theory and it is of extreme interest in theoretical physics as it delineates a wide class of relativistic models. Here, we propose a short digest on Lovelock theory that represents a very beautiful scenario to study how the differential geometry of gravity results corrected at short distance due to the presence of higher order curvature terms in the action. As in the modern literature of cosmology, the space-time has been supposed to be a dynamical manifold. Hence by admitting this fact in the present study, we will be concerned with the flow equations of all the Lovelock configurations. In particular, we shall make use of Ricci flow techniques to evolve the actions which are responsible for higher order gravity theory. Finally, we shall attempt to evolve the Lovelock tensor to generate a very useful non-linear heat diffusion equation that could analyze the mystery of higher order gravity theory.

Open Access Original Research Article

Unified Study of Lattice Dynamic of Potassium Iodide (KI)

U. C. Srivastava, K. S. Upadhyaya

Physical Science International Journal, Page 16-28

A unified description of a series of Phonon properties of potassium iodide (KI) by means of van der Waals three-body force shell model [VTBFSM] is presented. This model includes van der Waals interactions (VWI) and three-body interactions (TBI) in the framework of both ion polarizable rigid shell model (RSM). The present model has revealed much better descriptions of IR/Raman spectra and anhormonic and other dynamical properties of KI. A comparative study of the dynamical behaviour of KI has also been carried out. Agreement between the theoretical and experimental results, indicate the necessity of the adopted unified approach for the complete description of ionic crystals having NaCl structure. We conjecture that the incorporation of van der Waals interactions is essential for the complete harmonic dynamical behavior of KI.