Simulating a one-dimensional plasma

We describe a dynamical model of a one-dimensional plasma and present a simple algorithm for simulating the model on a computer. We use the algorithm to perform several numerical experiments that illustrate collective effects in plasma physics such as Debye screening and plasma oscillations

Time asymmetry in a dynamical model of the one-dimensional ideal gas

We present a simple dynamical model of the one-dimensional ideal gas and show how it can be used to introduce a number of fundamental ideas in statistical mechanics. We use the model to illustrate the role of initial conditions in explaining time asymmetry and show that although the dynamical model is time-reversal invariant, the macroscopic behavior of the gas can be time-asymmetric if the initial conditions are chosen properly

A toy model of electrodynamics in (1 + 1) dimensions

A model is presented that describes a scalar field interacting with a point particle in (1+1) dimensions. The model exhibits many of the same phenomena that appear in classical electrodynamics, such as radiation and radiation damping, yet has a much simpler mathematical structure. By studying these phenomena in a highly simplified model, the physical concepts involved may be more easily understood

Quantum field theory in (0 + 1) dimensions

We show that many of the key ideas of quantum field theory can be illustrated simply and straightforwardly by using toy models in (0 + 1) dimensions. Because quantum field theory in (0 + 1) dimensions is equivalent to quantum mechanics, these models allow us to use techniques from quantum mechanics to gain insight into quantum field theory. In addition, working in (0 + 1) dimensions considerably simplifies the mathematics, allowing the physical concepts involved to be exhibited more clearly

Laserlike and atomlike regimes in a one-atom laser

We consider a three-level model of a one-atom laser, and show that there are two limiting regimes of parameter space, one in which the system behaves like a conventional laser and one in which the system exhibits novel quantum properties. We show that in the first limiting regime, the model can be approximated by semiclassical laser theory, and in the second limiting regime the model can be approximated as an effective two-level atom. We also perform numerical simulations that confirm the limiting behaviors predicted by these approximate descriptions

Advanced action in classical electrodynamics

The time evolution of a charged point particle is governed by a second-order integro-differential equation that exhibits advanced effects, in which the particle responds to an external force before the force is applied. In this paper we give a simple physical argument that clarifies the origin and physical meaning of these advanced effects, and we compare ordinary electrodynamics with a toy model of electrodynamics in which advanced effects do not occur.Comment: 12 pages, 5 figure

The momentum distribution of a one-dimensional ideal gas of N atoms

We calculate the average momentum distribution and the average deviation from this distribution for a one-dimensional ideal gas of N atoms. The calculation is performed using analytical and numerical methods, and the results obtained using the two methods are compared.We use these results to show that in the limit of large N, almost all the possible microstates of an ideal gas have momentum distributions that are very close to the Maxwell distribution. We discuss the significance of this fact for understanding why an ideal gas approaches thermal equilibrium

Hidden variable theories and quantum nonlocality

We clarify the meaning of Bell's theorem and its implications for the construction of hidden variable theories by considering an example system consisting of two entangled spin-1/2 particles. Using this example, we present a simplified version of Bell's theorem and describe several hidden variable theories that agree with the predictions of quantum mechanics. These example theories clarify some subtle points, which are often misunderstood, regarding what it is that Bell's theorem actually establishes