A Simple Model of Endemicity to Analyse Spread and Control of COVID-19 in India

A simple model based on 2 parameters, time-dependent infectability and efficacy of containment measures, is written to analyse the spread and containment of an endemic outbreak. Data from the first wave of the outbreak of COVID-19 in India is analysed. Interestingly, growth and decay of infections can be seen as a competition between the ratio of logarithm of infectability and the logarithm of time vis-a-vis the efficacy of containment measures imposed. Containment time estimates are shown to exhibit the viability of the simple model

Non-linear propagation of electrostatic waves in relativistic Fermi plasma with arbitrary temperature

627-633Modulational instability of electron plasma waves has been investigated by using the quantum hydrodynamic (QHD) model for quantum plasma at finite temperature by deriving a non-linear Schrödinger equation including relativistic effects. It is shown that the electron degeneracy parameter and streaming velocity significantly affect the linear and non-linear properties of electron plasma waves in a finite temperature quantum plasma

Linear and non-linear propagation of electron plasma waves in quantum plasma

314-319Using one-dimensional quantum hydrodynamic model, the linear and non-linear characteristics of electron plasma waves have been studied both analytically and numerically in a I two-component unmagnetized dense quantum plasma with streaming motion. It is shown that quantum effect modifies the linear dispersion character of the electron plasma waves and streaming effect makes it possible the excitation of two distinct modes. To describe the non-linear behaviour, Korteweg de Vries equation is derived by using the standard reductive perturbation technique and incorporating quantum-mechanical effects. It is shown that depending on/some critical values of the quantum diffraction parameter both rarefactive and compressive type of solitons can exist in the model plasma. The structure of the solitary waves is shown to be significantly affected by the quantum plasma parameters and streaming motion.</span