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Fen Tamanaha
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Fen Tamanaha

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This must be pretty new. I'm not seeing it on Google Maps, at least where I think it should be.

https://goo.gl/maps/ccfKoxveRqj
 
Hawaii’s largest solar project continues to grow in Waianae, helping us move forward in achieving our state’s goal of 100% renewables by 2045. Photo provided by Eurus Energy America.
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... Do not attempt to adjust the picture. We are controlling transmission. If we wish to make it louder, we will bring up the volume. If we wish to make it softer, we will tune it to a whisper. We can reduce the focus to a soft blur, or sharpen it to crystal clarity. We will control the horizontal. We will control the vertical. For the next hour, sit quietly and we will control all that you see and hear...[1]

Ominous.



[1] This is, of course, part of the narration at the start of The Outer Limits .
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Who knew? Adjectives must be properly ordered.
 
Mark Forsyth tasted internet fame this week when a passage from a book he wrote went viral. He explains more language secrets that native speakers know without knowing.
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Interesting! Although I have heard "zag zig" in some contexts and not been upset :-)
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At last, now one can listen to an endless, ever-changing loop of the Hampster Dance.
You can tune control the frequency and quality of the branching. See the FAQ for more details. Branch Similarity Threshold: 50. Higher Quality More Branches. Branch Probability Range: % to %. Low High. Branch Probability Ramp-up Speed: 20%. Slow Fast. Loop extension optimization:.
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I know; it's Heaven.
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Put this on your desk so that everyone knows you have very high aspirations. But don't delay, there are only 500 of them.
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Don't bindly trust those Faraday Cages.
 
Faraday cages are one of the most basic tools in electrical anything. They're based on the principle that if you place a hollow, conductive container inside an electromagnetic field, then no matter what that field is on the outside, the container shields it: inside the container, the field is zero. These also work in reverse: if you put a field source inside a conductive container, the container will prevent that field from getting out.

This is pretty useful if you want to do something that could produce dangerous fields, like use microwaves to heat food. By wrapping it in a Faraday cage, you make sure that the resulting fields don't also heat everything in their vicinity.

Now, most Faraday cages aren't solid, conductive containers; it's been known for a long time that a wire mesh works just as well. Except it turns out that it doesn't.

Faraday invented the cage in 1836. From then until roughly the 1940's, the correct functioning of mesh cages has been a combination of lore and practical engineering: if you really care that your cage works (like in a microwave oven), you build it and measure what happens. The theory of them was worked out by Feynman in the 1940's – except it turns out that Feynman simply did it wrong. (In particular, he looked at wire meshes with constant charge on them, not constant voltage; the math was right, it simply solved the wrong problem)

According to Feynman's solution, what matters for a working Faraday cage is the proximity of the wires. Roughly, the depth into the cage at which it provides the needed field suppression drops exponentially as the wires move closer together. It turns out this isn't right: fields decay only linearly with wire spacing. What really matters is the thickness of the wires: the suppression does scale exponentially with that.

In practice, this explains a lot of open mysteries, like why your cell phone works inside an elevator, but not inside an underground parking garage. Elevators, under the old theory, should have been pretty good Faraday cages; how do the radio signals, which are just EM fields, get out? It turns out they aren't very good Faraday cages at all. Likewise, garages don't tend to have deliberate EM shielding on them, but they do have lots of rebar, and windows which are often grated. Put those together and the new theory tells you that you have a great Faraday cage.

Also in practice, this team now has a good method for calculating how Faraday cages will actually work ahead of time. It's not rocket science; it's simply solving the differential equations of electrodynamics for a cage. You can see some of the results in pictures below, where the density of lines indicates the field strength. (In all of those pictures, an EM source is to the right of the cage)

The moral of this story: if everyone assumes that there's a good theory for something, but nobody can actually find it worked out in detail, there's a good chance that there actually isn't one.

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By Lloyd N. Trefethen Nearly everyone has heard of the Faraday cage effect. So when I needed to learn about it, I assumed it would be a matter of looking in some standard physics books, maybe the ones I’d studied as an undergraduate. This was the beginning of a journey of surprises. The Faraday cage effect involves shielding of electrostatic and electromagnetic fields. A closed metal cavity makes a perfect shield, with zero fields inside, and tha...
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The space station sure has some impressive views.
 
Ciao! The southern tip of Italy was captured by the International Space Station crew over the weekend. Take a closer look: http://go.nasa.gov/2cZDZhD
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XKCD's climate change infographic will both delight and alarm you.
XKCD's massive, vertical climate change infographic
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Star Trek and Star Wars are insipiring but for very different reasons.
 
For the weekend: my own impudent, off-axis take on the 50th anniversary of Star Trek! How diametrically opposite Trek is, from Star Wars, in every moral sense. And you can see this in one trait - the size of the ship. Size does matter! Come find out why.





















Five decades ago, I was at the perfect age. Almost sixteen, pumped with eagerness for science and fiction and outer space and dreams of escaping the dreary prisons of home and high school. And suddenly on the dreary wasteland...
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It's nice to get some closure on what happened to the Philae comet lander.
 
Rosetta’s mission to Comet 67P/Churyumov–Gerasimenko has finally spotted the lost Philae lander. Pretty amazing photos reveal the lander tumbled on its side in a shadowed crevice, a fate long suspected suspected since it ran out of solar power soon after touch-down… or bounce-down. Ah well. A lot of science got done anyway, verifying much of my doctoral thesis. (And some bits from Heart of the Comet!) Thanks Europe! Now onward into space!
The final resting place of the European comet lander Philae is a mystery no more. After nearly two years of searching, the lander's shadowy grave on Comet 67P/Churyumov–Gerasimenko has been found in images from its mothership Rosetta.
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Ooh, I've always wanted a bowcaster. Even if I dig up the $2,500.00, where am I going to put it?
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A rather thoughtful analysis of something that's been happening in the US lately. The speeches at the DNC have been on themes of family values, patriotism, and American exceptionalism – traditionally Republican themes, but now (with that party's candidate having rejected all of these fairly soundly) up for grabs. The result is something rather interesting, and could have deep effects on politics down the line. This may be a key moment in the realignment of American political parties.

Worth the read, and a ponder.
Family values. Patriotism. The military. Even Ronald Reagan’s best line.
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