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T.R. Hummer
'Hidden Portal' Concept Described: First Tunable Electromagnetic GatewayWhile the researchers can't promise delivery to a parallel universe or a school for wizards, books like Pullman's Dark Materials and JK Rowling's Harry Potter are steps closer to reality now that researchers in China have created the first tunable electromagnetic gateway.
The work is a further advance in the study of metamaterials, published in New Journal of Physics (co-owned by the Institute of Physics and German Physical Society).
In the research paper, the researchers from the Hong Kong University of Science and Technology and Fudan University in Shanghai describe the concept of a "a gateway that can block electromagnetic waves but that allows the passage of other entities" like a "'hidden portal' as mentioned in fictions."
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T.R. Hummer
Scientists Pinpoint Source of Earth’s "Hum"It's not just whales that sing, the Earth does too. A pair of physicists at the University of California figured out that the Earth’s hum is caused not by earthquakes or atmospheric turbulence, but by ocean waves colliding with the seafloor.
About ten years ago researchers discovered infrasonic background noise of 3-7 mHz believed to originate from the solid Earth itself. claim to have the most convincing physical evidence yet. Using data from a wide-spread array of seismic recorders, Peter Bromirski and Peter Gerstoft, have pinpointed the Pacific coast of Central America as the dominate source of background noise, with the western coast of Europe acting as the main secondary source.
Hum beam power observations using the USArray EarthScope transportable array, which monitors seismic activity right across the US and its surrounding waters, combined with infragravity wave observations, show that the dominant source area of the Earth’s hum during winter months is the Pacific coast of North America, with the western coast of Europe a secondary source region.
Pbo_obs Within this new view of hum, long-wavelength surface waves - known as ocean swell - act as the mediator between the sky and the sea. As the swell reaches shallower waters, a portion of its energy is then transformed by non-linear processes into infragravity (IG) waves, which have even longer wavelengths than the surface waves. Some of the energy from IG waves affect the Earth, registering as blips at seismic recording stations around the world.
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Fast-spinning black holes might reveal all - physics-math - 08 August 2009 - New ScientistIT IS the ultimate cosmic villain: space and time come to an abrupt end in its presence and the laws of physics break down. Now it seems a "naked" black hole may yet emerge in our universe, after spinning away its event horizon.
In 1969, physicist Roger Penrose postulated that every singularity, or black hole, must be shrouded by an event horizon from which nothing, including light, can escape. His Cosmic Censorship Conjecture has it that singularities are always hidden.
If the conjecture doesn't hold, it would be bad news for cosmologists. If even one location in the universe cannot be described by the laws of physics, the future of the universe - as predicted by those laws - is cast into doubt. Our description of photons, for instance, may be undermined because those photons may have interacted with a naked singularity while zipping across the universe.
In theory, adding matter to a black hole could make it spin fast enough to shed its event horizon, but previously, physicists have calculated that the spin of black holes has an inherent speed limit that prevents such shedding. This limit is partly determined by the swirling tornado of space-time that surrounds a spinning black hole. Past simulations showed that if material was added that made space-time swirl faster, adding yet more material would be increasingly difficult because the increased centrifugal force might fling it outwards before it could reach the black hole's event horizon, spin it up and disrupt it.
Infalling matter can disrupt a black hole's event horizon, exposing a 'naked' singularity
However, these simulations began by adding matter to a black hole spinning at its maximum possible rate, say Ted Jacobson and Thomas Sotiriou at the University of Maryland at College Park. They simulated adding matter orbiting in the same direction to a black hole spinning just below its maximum rate. Their work suggests that the event horizon could then be disrupted and shed (www.arxiv.org/abs/0907.4146).
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