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...

In this paper, we evaluate the performance of a number of forecasting models of U.S. business fixed investment spending growth over the recent 1995:1-2004:2 out-of-sample period at multiple forecast horizons. The forecasting models are based on the conventional Accelerator, Neoclassical, Average Q, and Cash-Flow models of investment spending, as well as empirical models developed more recently ...

We employ a newly-developed partial cointegration system allowing for level shifts to examine whether economic fundamentals form the long-run determinants of dollar-pound exchange rate over recent period characterised by structural breaks and policy regime shifts. The paper models both short-run dynamic features using set variables that explicitly reflect quantitative monetary influence forward...

We evaluate the performance of an information aggregation mechanism (IAM) implemented inside Intel to forecast unit sales for the company. Developed, refined and tested in the laboratory using experimental methods, the IAM is designed specifically to aggregate information. Its implementation at Intel allows us to test its performance in a much more complex field environment. The IAM provides no...

Calcareous sands and podzols of four different ages (0, 3 100, 4200 and 5500 calendar years) form a soil chronosequence at Rheban Spit, a prograded sand barrier, near Orford on the east coast of Tasmania. In terms of profile morphology the soils range from undifferentiated quartz sand with shell at the youngest site, to a well-developed podzol with prominent AI, A, and B horizons at the oldest ...

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...

The spread of infectious diseases can be impacted by human behavior, and behavioral decisions often depend implicitly on a planning horizon-the time in the future over which options are weighed. We investigate the effects of planning horizons on epidemic dynamics. We developed an epidemiological agent-based model (along with an ODE analog) to explore the decision-making of self-interested indiv...

High-latitude regions store large amounts of organic carbon (OC) in active-layer soils and permafrost, accounting for nearly half of the global belowground OC pool. In the boreal region, recent warming has promoted changes in the fire regime, which may exacerbate rates of permafrost thaw and alter soil OC dynamics in both organic and mineral soil. We examined how interactions between fire and p...