We describe the different possibilities that a simple and apparently quite harmless classical scalar field theory provides to violate the energy conditions. We demonstrate that a nonminimally coupled scalar field with a positive curvature coupling ξ > 0 can easily violate all the standard energy conditions, up to and including the averaged null energy condition (ANEC). Indeed, this violation of...

A point particle approximation to the classical dynamics of well separated vortices of the abelian Higgs model is developed. The asymptotic static intervortex potential is calculated and used to model type II vortex scattering. A velocity dependent interaction Lagrangian for critically coupled vortices is derived, and reinterpreted geometrically to obtain a conjecture for the asymptotic form of...

We consider a system of coupled Klein-Gordon equations, which models one-dimensional nonlinear wave processes in two-component media. We find both linear and nonlinear solutions involving the exchange of energy between the different components of the system. The solutions are a continuum generalization of the classical example of energy exchange in Mandelshtam’s system of coupled pendulums. PAC...

A quantum computer, with controlled decoherence, constructed out of a lattice based array of qubits undergoing a particular local and unitary evolution is effectively a bose condensate. Presented is a coupled lattice gas system, a quantum lattice gas and a classical lattice gas in mutual contact through “external” potentials. The coupled lattice gas system behaves like liquid 4He where it is a ...

G protein-coupled receptors (GPCRs) affect many physiological processes by modulating both intrinsic membrane conductances and synaptic transmission. This study describes spontaneous miniature inhibitory postsynaptic currents mediated by vesicular dopamine release acting locally on metabotropic D2 receptors leading to the activation of a G protein-coupled inwardly rectifying potassium conductan...

We study the emergence of collective synchronization in large directed networks of heterogeneous oscillators by generalizing the classical Kuramoto model of globally coupled phase oscillators to more realistic networks. We extend recent theoretical approximations describing the transition to synchronization in large undirected networks of coupled phase oscillators to the case of directed networ...

We establish analogues of the Hawking and Penrose singularity theorems based on (a) averaged energy conditions with exponential damping; (b) conditions on local stress–energy averages inspired by the quantum energy inequalities satisfied by a number of quantum field theories. As particular applications, we establish singularity theorems for the Einstein equations coupled to a classical scalar f...

In the present paper scalar macroscopic models for traffic and pedestrian flows are coupled and the resulting system is investigated numerically. For the traffic flow the classical Lighthill-Whitham model on a network of roads and for the pedestrian flow the Hughes model are used. These models are coupled via terms in the fundamental diagrams modeling an influence of the traffic and pedestrian ...

We continue our investigation of an improved quantization scheme for spherically symmetric loop quantum gravity. find that in the region where black hole singularity appears classical theory, theory contains semi-classical states approximate general relativity coupled to effective anisotropic fluid. The is eliminated and space-time can be continued into a white space-time. This similar previous...

The classical and quantum dynamics of noncanonically coupled oscillators is investigated in its relation to Lie superalgebras. It is shown that the quantum dynamics admits a hidden (super)hamiltonian formulation and, hence, preserves the initial operator relations.