Power from thin air | The Economist

Wireless technology: It is already possible to send electricity without wires. Can devices be powered using ambient radiation from existing broadcasts?

ANYONE whose mobile phone has ever run out of juice—which means, these days, more than half the world’s population—will like the idea of getting electrical power out of the air. The notion is far from new. A little over a century ago, the inventor Nikola Tesla drew up ambitious plans to transmit electrical power without wires. He carried out a series of experiments in which electric lights were illuminated via electrostatic induction, by connecting them to metal sheets suspended in a strong electric field produced by a distant transmitter. In 1898 he proposed a “world system” of giant towers that would form both a global wireless communications network and a means of delivering electricity over large areas without wires.

Pretty awesome if it can be made to work on a large scale, especially since solar power cells are still very inefficient, and there would be many applications for this sort of technology where radio waves penetrate, but light doesn’t (I’m thinking indoors, mainly).

Reminds me of a good book I read on the whole world of energy production and delivery: The Scientist, the Madman, the Thief and their Lightbulb.

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Good news about the middle-age brain – Holy Kaw!


Good news about the middle-age brain

Forget version 4 of the iPhone as today’s big news. This is really important. Barbara Strauch, former deputy science editor of The New York Times published a book called The Secret Life of the Grown-up Brain: The Surprising Talents of the Middle-Aged Mind. Here’s the paragraph that made my day:

“If you have to learn new information — a new computer system at work — brand new information can take a little longer on average as our brains age. [But] our brains in modern middle age have enormous capacity and are formidable in their powers to get the gist of an argument, to see the big picture. Someone I know who teaches at Columbia says the kids are smart, but they don’t seem to connect the dots. What we have in the middle-age brain is that ability to connect the dots. I’ve had many people tell me, ‘I can’t remember what I had for breakfast, but solutions pop into my head.’”

Now where did I put my iPhone?

Full interview at Boston.com.

I’ve had that very same feeling for quite a while now, this inability to remember trivial things like what I ate yesterday, while getting better at the “big picture” things (something I’ve always been quite good at). So I guess my abilities as Software Architect aren’t due to wane just yet… Hooray!

Fractal Haze Could Solve Weak-Sun Mystery for Early Earth | Wired Science

Science. It just works.

A thick haze of organic material let the early Earth soak up the sun’s warmth without absorbing harmful ultraviolet rays, according to a new study.

The model offers a new twist on an old puzzle: Although the sun was so dim billions of years ago that the Earth should have been a ball of ice, the young planet had liquid oceans capable of supporting life.

“Given these recent papers, we can probably say the early faint sun problem is not one of the problems anymore in solving the origin of life,” said astrophysicist Christopher Chyba of Princeton University, who was not involved in the new work.

The sun should have been up to 30 percent less bright 3.8 billion to 2.5 billion years ago, according to studies of the lifecycles of sun-like stars. If the Earth’s atmosphere had the same composition then as it does now, it would have frozen over completely, like Jupiter’s moon Europa. But geological records show the Earth was at least as warm and wet then as it is today.

Scientists have struggled with this “faint young sun paradox” since 1972, when astronomers Carl Sagan and George Mullen suggested that an atmosphere containing a small amount of ammonia, a powerful greenhouse gas, could have warmed the Earth enough to keep the oceans liquid. But a later study showed that ultraviolet radiation from the sun would destroy the ammonia in the atmosphere and cancel out its warming effects.

Sagan countered in 1996 that the early atmosphere would have produced a thick cloud of organic haze, much like the orange cloud that enshrouds Saturn’s moon Titan. This haze would have blocked ultraviolet light but let in visible light, letting the Earth tan without getting burnt.

But early models assumed the haze particles were spheres, and that when individual particles collided, they globbed together to make bigger spheres. These spheres blocked visible light as well as ultraviolet light, and left the Earth’s surface even colder.

“It basically led us to a dead end where we couldn’t have a warm early Earth,” said Eric Wolf, a graduate student in atmospheric sciences at the University of Colorado at Boulder and the first author of the new study in Science June 4.

Wolf and coauthor Brian Toon realized that assuming the haze particles were spherical was too simple. Instead of combining to make bigger spheres, tiny haze particles no more than 100 nanometers across could form long chains, like strings of pearls. These chains would link up and branch off each other in a complicated fractal geometry, similar to the structure of clouds.

These strands of haze would form fluffy, airy structures that would let in visible light while blocking ultraviolet light, Wolf said.

“If you take into account the shape factor,” he said, “it turns out that the haze would be quite a strong ultraviolet shield while being relatively transparent in the visible. Visible light can reach through the haze and reach the surface.”

Without the destructive ultraviolet light, ammonia could build up under the haze and warm the Earth efficiently, Wolf said. Only a few parts per million of ammonia would be enough to offset the faint young sun.

But if early organisms could have looked up, they wouldn’t have seen a clear blue sky. The sky would be dim and rust-colored, like Titan’s.

“We’re really dealing with this completely alien world on the early Earth,” Wolf said.

Wolf’s study comes shortly after an April 1 paper in Nature that proposed another solution to the faint young sun paradox: The early Earth was darker, and therefore absorbed more heat. Both explanations could be right, Chyba said.

“It seems likely that the answer is going to be a composite explanation,” he said. “You cobble together a number of factors and you solve the paradox that way.”

The next step should be looking at ancient rocks to determine what the early Earth’s atmosphere was really made of, Chyba added. “That’s going to be really hard, because those rocks are really worked over. But that’s probably where the field is heading now.”

Image: Haze on Titan./NASA/Cassini

See Also:

via wired.com

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Slashdot Games Story | Video Gamers Have Power Over Their Dreams

Video Gamers Have Power Over Their Dreams

on Wednesday May 26, @05:50PM
Posted by timothy on Wednesday May 26, @05:50PM
from the nocturnal-excursions dept.

Ponca City, We love you writes “Live Science reports that researchers say playing video games before bedtime may give gamers an unusual level of awareness and control in their dreams which could provide an edge when fighting nightmares or even mental trauma. ‘If you’re spending hours a day in a virtual reality, if nothing else it’s practice,’ says Jayne Gackenbach, a psychologist at Grant MacEwan University in Canada who says that hard core gamers represent the leading edge of immersion in virtual worlds that increasingly has come to define a large part of contemporary entertainment and communication. ‘Gamers are used to controlling their game environments, so that can translate into dreams.’ One intriguing theory holds that dreams are a sort of threat simulation where nightmares help organisms hone their skills in a protective environment, and ideally prepare organisms for a real-life situation. To test that theory, Gackenbach conducted a study using independent assessments that coded threat levels in after-dream reports and found that gamers experienced less or even reversed threat simulation (in which the dreamer became the threatening presence), with fewer aggression dreams overall. In other words, a scary nightmare scenario turned into something ‘fun’ for a gamer.”

I’ve definitely felt that my dreams were more “active” when I went to bed straight after a gaming session. On the other hand, having a completely interactive dream has prevented me from actually falling asleep.

Have any of you experienced similar? What was it like?

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