We describe the application of a gravity wave-generating technique to certain higher dimensional black holes. We find that the induced waves generically destroy the event horizon producing parallelly propagated curvature singularities. Based on a talk presented at the Seventh Canadian Conference on General Relativity and Relativistic Astrophysics in Calgary, AB, Canada, May 31 – June 7, 1997. E...

Laboratory and epidemiological evidence indicate that ambient humidity modulates the survival and transmission of influenza. Here we explore whether the inclusion of humidity forcing in mathematical models describing influenza transmission improves the accuracy of forecasts generated with those models. We generate retrospective forecasts for 95 cities over 10 seasons in the United States and as...

     Comparing the ability of ST and WRB systems to describe soils with clay-enriched horizons was the aim of the present research. In arid and semi-arid regions of Iran, two study sites were considered. Three pedons at each study site were selected, described and sampled. Soils were classified based on ST (2014) and WRB (2015) systems. The micro-morphological investigations were done to confir...

A general analysis for characterizing and classifying ‘isolated horizons’ is presented in terms of null tetrads and spin coefficients. The freely specifiable spin coefficients corresponding to isolated horizons are identified and specific symmetry classes are enumerated. For isolated horizons admitting at least one spatial isometry, a standard set of spherical coordinates are introduced and ass...

Organic soil horizons function as important controls on the thermal state of near-surface soil and permafrost in high-latitude ecosystems. The thermal conductivity of organic horizons is typically lower than mineral soils and is closely linked to moisture content, bulk density, and water phase. In this study, we examined the relationship between thermal conductivity and soil moisture for differ...

The concept of transparent and opaque horizons is defined. One example of opaqueness is the presence of a firewall. Two apparently contradictory statements are reconciled: The overwhelming number of black hole states have opaque horizons; and: All black holes formed by natural processes have transparent horizons. A diagnostic is proposed for transparency, namely that the computational complexit...

QED in two-dimensional Minkowski space contains a single physical state as seen either by an inertial observer or by a constantly accelerating Rindler observer. However in Feynman gauge if one takes a generic representative of the physical Minkowski state and traces over all left Rindler states, one does not arrive at the physical right Rindler state, but rather at a “density matrix” with negat...

Isolated horizons [1], much like Killing horizons [2], were introduced in order to deal with the more practical problems involving black holes. Both formulations are local, in contrast with the global nature of event horizons [3]. However, isolated horizons, unlike Killing horizons, do not require a Killing vector field in their neighbourhood. Thus, isolated horizons are characterized by a weak...

Spherical configurations that are very massive must be surrounded by apparent horizons. These in turn, when placed outside a collapsing body, have a fixed area and must propagate outward with a velocity equal to the velocity of radially outgoing photons. That proves, within the framework of the (1+3) formalism and without resorting to the Birkhoff theorem, that apparent horizons coincide with e...