Thermal energies of classical and quantum damped oscillators coupled to reservoirs

We consider the global thermal state of classical and quantum harmonic oscillators that interact with a reservoir. Ohmic damping of the oscillator can be exactly treated with a 1D scalar field reservoir, whereas general non-Ohmic damping is conveniently treated with a continuum reservoir of harmonic oscillators. Using the diagonalized Hamiltonian of the total system, we calculate a number of thermodynamic quantities for the damped oscillator: the mean force internal energy, mean force free energy, and another internal energy based on the free-oscillator Hamiltonian. The classical mean force energy is equal to that of a free oscillator, for both Ohmic and non-Ohmic damping and no matter how strong the coupling to the reservoir. In contrast, the quantum mean force energy depends on the details of the damping and diverges for strictly Ohmic damping. These results give additional insight into the steady-state thermodynamics of open systems with arbitrarily strong coupling to a reservoir, complementing results for energies derived within dynamical approaches (e.g. master equations) in the weak-coupling regime.Comment: 13 page

Absorption in dipole-lattice models of dielectrics

We develop a classical microscopic model of a dielectric. The model features nonlinear interaction terms between polarizable dipoles and lattice vibrations. The lattice vibrations are found to act as a pseudo-reservoir, giving broadband absorption of electromagnetic radiation without the addition of damping terms in the dynamics. The effective permittivity is calculated using a perturbative iteration method and is found to have the form associated with real dielectrics. Spatial dispersion is naturally included in the model and we also calculate the wavevector dependence of the permittivity.Comment: 13 pages, 9 figures; references added to section

Justice: A Lady in Distress

This Article contends that the prevalent public ignorance of the methods, objectives, and development of the justice system is the root of indifference, hostility and public desuetude. This public illness plaguing the legal system is in need of remedy. Remedies to the legal system should be directed at the segments of the profession which will effectuate such reforms: the Judiciary (the Bench), Lawyers (the Bar), and Law Schools. The author concludes that the legal system is in constant need of reforms that continue enhance the legal system as society’s values change and develop

Evaluation of the effects of space environment exposure on index of refraction and extinction coefficients of Apollo window materials

Temperature and radiation effects on index of refraction and extinction coefficients of Apollo window material

Supergravity and IOSp(3,1|4) gauge theory

A new formulation of simple D=4 supergravity in terms of the geometry of superspace is presented. The formulation is derived from the gauge theory of the inhomogeneous orthosymplectic group IOSp(3,1|4) on a (4,4)-dimensional base supermanifold by imposing constraints and taking a limit. Both the constraints and the limiting procedure have a clear {\it a priori} physical motivation, arising from the relationship between IOSp(3,1|4) and the super Poincar\'{e} group. The construction has similarities with the space-time formulation of Newtonian gravity.Comment: 17 pages. Expanded version. To appear in Class. Quantum Gra

Editor’s Introduction

In this issue of the journal we are delighted to present eight articles that cover several key areas across engineering management. The discipline of engineering management [...

Does low-carbon pilot policy in China improve corporate profitability? The role of innovation and subsidy

In an effort to aggressively combat climate change, China implemented a low-carbon city pilot policy (LCCP) in 2010. This study analyzes the impact LCCP, which is a specific environmental regulation on firms' profitability and innovation performance. The study argues that LCCP has an impact on corporate profitability by enhancing corporate innovation. Based on the data of A-share listed enterprises from 2005 to 2020, this study employ a multi-period Differences-in-Differences (DID) method to explore whether and how the LCCP affects the profitability of enterprises. The study finds that: (1) LCCP can greatly increase enterprise profitability; (2) LCCP has a more prompt effect on the profitability of large companies; (3) LCCP increases innovation investment and financial subsidies, which in turn increases company profitability. The study enriches the body of knowledge on the effects of LCCP on large companies and SMEs, and provides crucial evidence base for the consequences of government's strategy to assist firms in achieving the low carbon growth

Tradition and Innovation in Construction Project Management

Construction project management is a multidimensional discipline that requires meticulous consideration of various critical aspects, including cost, quality, schedule requirements, as well as social and environmental impacts [...

Editor’s Introduction

In this issue of the Engineering Management Journal (EMJ), we are delighted to present eight new articles that address several key areas across the engineering management discipline. The scope of the research studies highlights the application as well as the range of approaches adopted in engineering management [...

Jarzynski equality for a gas particle driven out of equilibrium

ArticleThis version: arXiv:1404.5181v1 [cond-mat.stat-mech]. Available from ArXiv.org via the link in this record.One particle in a classical perfect gas is driven out of equilibrium by changing its mass over a short time interval. The work done on the driven particle depends on its collisions with the other particles in the gas. This model thus provides an example of a non-equilibrium process in a system (the driven particle) coupled to an environment (the rest of the gas). We calculate the work done on the driven particle and compare the results to Jarzynski's equality relating a non-equilibrium work process to an equilibrium free-energy difference. The results for this model are generalised to the case of a system that is driven in one degree of freedom while interacting with the environment through other degrees of freedom