introduction air pollution has harmful effect on human health and the environment. accordingly, considerable effort has been put to analyze the air pollutants. one important issue is the spatial distribution of these pollutants. dispersion of the pollutants released from sources on the ground is mostly driven by the planetary boundary layer where turbulent flow causes mixing of the content of t...

Fermat’s principle applied to a flat metric in the plane yields the phase of a Bessel function in the periodic domain for a constant index of refraction. Gravitational forces cause the index of refraction to vary and lead to a modified phase of the Bessel function. A distinction is made between the forces that cause acceleration: the gravitational force affects the optical properties of the med...

The equations of physics, generally, are invariant under the symmetry groups of infinitesimal space and time translations. This means that energy and momentum are conserved in “isolated” systems, that is, systems that do not couple physically to anything outside of themselves. Among the propellantless propulsion schemes of interest in the context of “breakthrough propulsion physics”, however, a...

In this paper, I test by numerical simulations the results of Del Popolo & Gambera (1998), dealing with the extension of Chandrasekhar and von Neumann’s analysis of the statistics of the gravitational field to systems in which particles (e.g. stars, galaxies) are inhomogeneously distributed. The paper is an extension of that of Ahmad & Cohen (1974), in which the authors tested some results of t...

A low-speed centrifuge was used to study the tropic responses of Phycomyces sporangiophores in darkness to the stimulus of combined gravitational and centrifugal forces. If this stimulus is constant the response is a relatively slow tropic reaction, which persists for up to 12 hours. The response is accelerated by increasing the magnitude of the gravitational-centrifugal force. A wholly differe...

multiple traveling salesman problem (mtsp) is one of the most popular operation research problem and is known as combinatorial optimization problems. mtsp is an extension version of the famous and widely used problem named traveling salesman problem (tsp). because of its benefices in various domains, many researchers have tried to solve that, and many methods have proposed so far. mtsp is a np-...

A point particle of mass μ moving on a geodesic creates a perturbation hab, of the spacetime metric gab, that diverges at the particle. Simple expressions are given for the singular μ/r part of hab and its tidal distortion caused by the spacetime. This singular part hab is described in different coordinate systems and in different gauges. Subtracting hab from hab leaves a regular remainder hab....

A point particle of mass μ moving on a geodesic creates a perturbation hab, of the spacetime metric gab, that diverges at the particle. Simple expressions are given for the singular μ/r part of hab and its distortion caused by the spacetime. This singular part hS ab is described in different coordinate systems and in different gauges. Subtracting hS ab from hab leaves a regular remainder h R ab...

Since general relativity is a consistent low energy effective field theory, it is possible to compute quantum corrections to classical forces. Here we compute a quantum correction to the gravitational potential between a pair of polarizable objects. We study two distant bodies and compute a quantum force from their induced quadrupole moments due to two-graviton exchange. The effect is in close ...

We review recent theoretical progress in the so-called self-force problem of a general relativistic two-body system. Although a two-body system in Newtonian gravity is a very simple problem, some fundamental issues are involved in relativistic gravity. Besides, because of recent projects for gravitational wave detection, it has become possible to see those phenomena directly via gravitational w...