Quite recently, some new mathematical approaches to black holes have appeared in the literature. They do not rely on the classical concept of event horizon — which is very global, but on a the local concept of hypersurfaces foliated by trapped surfaces. After a brief introduction to these new horizons, we focus on a viscous fluid analogy that can be developed to describe their dynamics, in a fa...

Soil properties change with depth. Layers of soil that are nearly parallel with the soil surface and that are distinguishable from adjacent layers are called soil horizons. Horizons are visible on the vertical wall of a pit dug into the soil; the entire series of horizons visible on this wall is known as a soil profile. An idealized soil profile is illustrated in Figure 1. Soil classification r...

Merging event horizons of the binary black holes will be investigated. Though recent development of the numerical study of the binary black hole coalescence has shown that their apparent horizons can orbit for many periods in the case of appropriate initial conditions, the apparent horizons only suggests the existence of an event horizon surrounding them. In the present article, we discuss how ...

Chruściel and Galloway constructed a Cauchy horizon that is nondifferentiable on a dense set. We prove that in a certain class of Cauchy horizons densely nondifferentiable Cauchy horizons are generic. We show that our class of densely nondifferentiable Cauchy horizons implies the existence of densely nondifferentiable Cauchy horizons arising from partial Cauchy surfaces and also the existence o...

Using monthly forecast data from Consensus Economics Inc. for 18 developed countries reported over 24 different forecast horizons during 1989-2004, we found wide diversity in the quality of forecasts across countries, and the horizons at which forecasts start becoming useful. For only seven countries (viz., Austria, Belgium, Canada, Denmark, Germany, Norway and U.S.) the initial 24-month-ahead ...

The characterization of Last Glacial millennial-timescale warming phases, known as interstadials or Dansgaard-Oeschger events, requires precise chronologies for the study of paleoclimate records. On the European continent, such chronologies are only available for several Last Glacial pollen and rare speleothem archives principally located in the Mediterranean domain. Farther north, in continent...