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In the Blink of Bird’s Eye, a Model for Quantum Navigation | Wired Science | Wired.com
m.wired.com/wiredscience/2011/01/quantum-birds/, posted 2011 by peter in bird nature physics science
European robins may maintain quantum entanglement in their eyes a full 20 microseconds longer than the best laboratory systems, say physicists investigating how birds may use quantum effects to “see” Earth’s magnetic field.
Quantum entanglement is a state where electrons are spatially separated, but able to affect one another. It’s been proposed that birds’ eyes contain entanglement-based compasses. Conclusive proof doesn’t yet exist, but multiple lines of evidence suggest it. Findings like this one underscore just how sophisticated those compasses may be.
“How can a living system have evolved to protect a quantum state as well — no, better — than we can do in the lab with these exotic molecules?” asked quantum physicist Simon Benjamin of Oxford University and the National University of Singapore, a co-author of the new study. “That really is an amazing thing.”
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In the Blink of Bird’s Eye, a Model for Quantum Navigation | Wired Science | Wired.com
www.wired.com/wiredscience/2011/01/quantum-birds/, posted 2011 by peter in bird cognition msm physics science toread
European robins may maintain quantum entanglement in their eyes a full 20 microseconds longer than the best laboratory systems, say physicists investigating how birds may use quantum effects to “see” Earth’s magnetic field.
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Even in laboratory systems, atoms are cooled to near–absolute-zero temperatures to maintain entanglement for more than a few thousandths of a second. Biological systems would seem too warm and too wet to hold quantum states for long, yet that’s exactly what they appear to do.
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HTwins.net - The Scale of the Universe
htwins.net/scale/index.html, posted 2010 by peter in flash physics science space visualization
Zoom from the edge of the universe to the quantum foam of spacetime and learn the scale of things along the way!
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Rethinking Einstein: The end of space-time - physics-math - 09 August 2010 - New Scientist
www.newscientist.com/article/mg20727721.200-rethinking-einstein-the-end-of-spacetime.html?full=true, posted 2010 by peter in physics science space
So Horava did the unthinkable and amended Einstein's equations in a way that removed Lorentz symmetry. To his delight, this led to a set of equations that describe gravity in the same quantum framework as the other fundamental forces of nature: gravity emerges as the attractive force due to quantum particles called gravitons, in much the same way that the electromagnetic force is carried by photons. He also made another serious change to general relativity. Einstein's theory does not have a preferred direction for time, from the past to the future. But the universe as we observe it seems to evolve that way. So Horava gave time a preferred direction [...].
With these modifications in place, he found that quantum field theories could now describe gravity at microscopic scales without producing the nonsensical results that plagued earlier attempts. "All of a sudden, you have new ingredients for modifying the behaviour of gravity at very short distances," Horava says.
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Model describes universe with no big bang, no beginning, and no end
www.physorg.com/news199591806.html, posted 2010 by peter in physics science space toread
“We view the speed of light as simply a conversion factor between time and space in spacetime,” Shu writes. “It is simply one of the properties of the spacetime geometry. Since the universe is expanding, we speculate that the conversion factor somehow varies in accordance with the evolution of the universe, hence the speed of light varies with cosmic time.”
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The case of the 500-mile email
www.ibiblio.org/harris/500milemail.html, posted 2010 by peter in email history humor networking physics statistics
"We can't send mail farther than 500 miles from here," he repeated.
"A little bit more, actually.
Call it 520 miles.
But no farther."
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Bureau 42 | Summer School 2010.1: Quantum Physics
www.bureau42.com/view/6841/summer-school-2010-1-quantum-physics, posted 2010 by peter in education free inpdf math physics science toread
The onset of summer is no excuse to stop learning. In this year’s session, we will address Quantum Physics. Be here each Monday morning through July and August for a new lesson in the nine part series, covering graduate level physics concepts with grade school math, or no math at all. The first lesson: Classical Thinking: Why Does It Fail?
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A Very Scary Fireworks Show: Exploding H-Bombs In Space : NPR
www.npr.org/templates/story/story.php?storyId=128170775, posted 2010 by peter in environment history physics science space toread video
Today these radiation belts are called Van Allen belts. Now comes the surprise: While looking through the Van Allen papers at the University of Iowa to prepare a Van Allen biography, Fleming discovered "that [the] very same day after the press conference, [Van Allen] agreed with the military to get involved with a project to set off atomic bombs in the magnetosphere to see if they could disrupt it."
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The plan was to send rockets hundreds of miles up, higher than the Earth's atmosphere, and then detonate nuclear weapons to see: a) If a bomb's radiation would make it harder to see what was up there (like incoming Russian missiles!); b) If an explosion would do any damage to objects nearby; c) If the Van Allen belts would move a blast down the bands to an earthly target (Moscow! for example); and — most peculiar — d) if a man-made explosion might "alter" the natural shape of the belts.
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VIS - Thomas Müller
www.vis.uni-stuttgart.de/~muelleta/IntBH/, posted 2010 by peter in art free graphics linux physics science simulation software space video windows
The optical appearance of the stellar sky for an observer in the vicinity of a black hole is dominated by bending of light, frequency shift, and magnification caused by gravitational lensing and aberration. Due to the finite apperture of an observer's eye or a telescope, Fraunhofer diffraction has to be taken into account. Using todays high performance graphics hardware, we have developed a Qt application which enables the user to interactively explore the stellar sky in the vicinity of a Schwarzschild black hole. For that, we determine what an observer, who can either move quasistatically around the black hole or follow a timelike radial geodesic, would actually see.
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Speculating about the Universe as a quantum fluid
arstechnica.com/science/news/2010/01/quantum-universe.ars, posted 2010 by peter in msm physics science
[Hitoshi Murayama] proposes that the Universe is, in fact, a quantum fluid, somewhat like a superconductor. How does this work? The analogy with superconductivity is apt because superconductors reject magnetic fields. That is, the charges in a superconductor arrange themselves such that the field lines of a magnetic field get bent around the super-current. Now, imagine sitting in the superconductor, trying to make a magnetic field.
What you would see is that the field was incredibly short-ranged because of the way the field would interact with the surrounding charges. Therein lies the idea. Imagine that the Universe is a quantum fluid that interacts very strongly with the strong force and weak forces, but ignores gravity and electromagnetism.
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