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The Year In Ideas
popo writes "The New York Times Magazine has a review of the year's most original and interesting ideas. They include "The Tornado in a Can" ("A contained cyclone, it turns out, is very useful for pulverizing things") and David Stevenson's real-life proposal to dig to the center of the Earth. by sinking heavy iron through the Earth's mantle."
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Speaking of top ideas, check out SlipHead.com. Its an open forum for the free exhange of ideas - similar to the way the open software movement works. Get recognized for having the best ideas, and who knows, maybe you'll even catch the eye of an investor!
Yes, water weighs 8.34 lb/gal. That means ~240 gallons of water would be in the two tons of trash. 240 gallons of water is ~32 ft^3. While I do believe I overlooked the water loss, I don't believe it could be all water.
but the iron is not going to get heavier on its way to the core. As far as I can remember the gravity that the iron feels is just the gravity from the sphere of mass below the iron, and so the thing should become lighter, regardless of its mass being the same.
It's sort of neat to see a story like this, because Dr. Stevenson was one of my advisors at Caltech. He's a great guy with a cool New Zealand accent and a wide assortment of knowledge about almost everything. But I can shed a little light on this, both because I know him and because I have a geology background.
First, for the credulous, he's semi-joking. The physics of the iron sinking into the core is actually plausible, but his tone when talking about "generating a crack in the crust" is tongue-in-cheek. This would require a much larger nuclear detonation, say, than has ever been tested by anybody. The seismic consequences would be... bad. What's more, we aren't anywhere even close to being able to design probes that could survive such an environment and send messages back.
To dispel a common misconception, the interior of the earth is NOT molten. Omitting some interesting boundary layers, the Earth is composed of the following chunks from the inside out: the inner core (solid iron alloy), the outer core (molten iron alloy), the mantle (solid rock), and the crust (we live on it). If you're curious as to how we know, it's because liquids and solids have dramatically different properties as far as transmitting seismic waves. I just found a decent site at JPL here that illustrates the earth's structure nicely, although it appears to have been written for grade schoolers.
The idea that the mantle is liquid is one of the most widely held misconceptions about major geological concepts. It exhibits ductile deformation, so it flows something like a liquid, with a speed of centimeters or meters per year. Magma, however, results when rock is pushed up into the crust from the mantle - the decrease in pressure lowers the melting temperature. It can also be generated when water seeps into hot rocks - wet rock has a lower melting temperature. It is NOT evidence that the mantle itself is liquid.
So why would this work? A large body of iron would be much denser than mantle rock, and at a hundred million kilograms, the net downward force would be considerable enough to force mantle rock out of the way. I'm too lazy to figure out the physics for this post, but I would imagine this is the content of the Nature article. The interesting question would be, "would ductile deformation occur quickly enough to get the iron down in a reasonable amount of time?" The answer, apparently, is 'yes'.
Regardless, I don't think the plan is to get that far in that this really becomes an issue, but I don't know enough about geology to know how far down they plan to go. But assuming that the earth is molten once they break through the chewy, chocolate-coated outer crust (sorry, I haven't yet had breakfast), I suppose the amount of force needed wouldn't be as great anyway.
If you can't tell, this was all speculation, i.e. I'm pulling it out of my ass. But that's my best guess.
This is from: billboards that watch you
Mobiltrak's technology relies on a little-known fact about car radios: they don't just receive signals; they also emit them. A car radio tunes to a particular station by mixing the signal from the ether with its own internally generated signal. It's that faint internal signal that the Mobiltrak dish picks up.
Can someone explain this? From Mobiltrak's FAQ, it implies the "internal signal" is just RF noise - and that its noise signature is different depending upon the station you're tuned into. Is RF noise really that loud? If so, does it also mean its also theoretically possible to determine what any electronic appliance is doing?
Here is my favorite article of the collection.
Maybe we deserve this world ?
And for the really lazy:
Airborne Humans, Biblical Taxation, Billboards That Know You, Bite-Size Nukes, Body Language Reveals All, Cancer Vaccine, The, Cinema Meets Real Life, Civil Disobedience Against Affirmative Action, Coincidence Theory, Darknets, Drought-Proof Lawn, The, Enough Debating -- Let's Start Hating, Espresso You Can't Mess Up, Ethical Sneaker, The, Fish-Eater's Cheat Sheet, The, Flop Penance, Food Simulator, The, Foolproof Umpire, The, Forget the South, Futures Markets in Everything, G.I. Bill for College Athletes, Give Felons the Vote, G.P.S. Art, Gratitude Visits, Gray-Goo Problem, The, Hammock Doesn't Work Anymore, The, Hit Song Science, Homeland-Security Neighborhood Watch, The, Injectable Beauty, Instantly Passe Trend, The, Iraq, Outsourced, Jules Verne Project, The, Junk Food Is Good for You, Kid Power, Labor Disputes Can Be Deadly for Consumers, Makeup for Men, Mind Over Matter, for Real, New Tools for an Occupation, News Guarantees, Nicotini, The, Offloading Your Memories, Pod Car, The, Post-Belief
The mantle is at really absurd pressures, on the order of millions of atmospheres. Water at this pressure does not become vapor, but rather Something Weird.