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Fen Tamanaha
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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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Using a cluster of galaxies containing the mass of 100,000,000,000,000 Suns to uncover faint first-generation galaxies. To boldly go...
 
Hubble boldly peers deeper into the universe than ever before, uncovering some of the farthest objects ever seen: http://go.nasa.gov/2acuYSD
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OMG! It looks like we're going all in on Google.
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Mezmerizing.
 
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Motion capture has gotten amazing. Gorgeous work by Method Design. 2016 AICP Sponsor Reel - Dir Cut
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Wow, Zippy's is 50! The parking lot looks about the same, but the building has grown.
 
This year Zippy's 50th Anniversary! To better tell our stories... we want you to share your memorable Zippy's experience! Email your stories to marketing@zippys.con Your story could be featured in a magazine!
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Fen Tamanaha

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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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Now that's a unique perspective.
 
Our #EPIC camera was collecting Earth data when the moon photobombed its way into the shot: http://go.nasa.gov/29tGa9n
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Wow!
Van Gogh’s The Starry Night can be recreated in real life in two ways: one of them is to be on drugs, and the other, apparently, is to swirl paint on water like artist Garip Ay. It’s sort of illegal to do the first thing, but you can watch how Ay recreates Starry Night in the video below. Check out how the colors blend together and how the swirls settle in to reach that classic effect.
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Super cool.
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Amazon has some interesting categorizations for items.
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Outlaws, I guess.
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