What's an order of magnitude among friends?
I think you need to shift the decimal place one over. It would be 186,200 miles long, if you're talking about the distance a photon can travel in a second (in vacuum).
A team of scientists at Cornell University in the US has demonstrated a way to bend light in such a way that it effectively hides an event from happening – what they call a "spatio-temporal cloaking" scheme. The team, which is funded by DARPA, has built on work by Imperial College London, which showed that it was theoretically …
Flying cars and vacations on the moon, for the time being, have run into a couple of nasty reality checks.
For the first, it's the basic fact of gravity: what goes up must come down, so if your flying car breaks down OVER the middle of nowhere, where does that leave you?
For the second, it seems to escape some people that getting something out of the earth's gravity well takes an extraordinary amount of energy. if we want space travel to be more ubiquitous, we're gonna need to lick the problem of a better source of escape energy first: something like an electric->kinetic converter useable up to over 30,000km/h.
"For the first, it's the basic fact of gravity: what goes up must come down, so if your flying car breaks down OVER the middle of nowhere, where does that leave you?"
In the middle of nowhere most likely, which is where we'll meet Courage the small dog. Win-win (if you like the cartoon that is ;-)).
"if we want space travel to be more ubiquitous, we're gonna need to lick the problem of a better source of escape energy first"
This is why people above spoke of "being in the future".
While airplanes come in all shapes and sizes they have a number of differences from the flying car concept. They require dedicated areas to operate. Can't just set one down in front of the house or like that. Pilots receive specialist training that goes well beyond your average road exam. And since airplanes don't suffer from the design constraints of the concept of flying cars (think objects the size--at worst, slightly larger--of the average automobile), certain aerodynamic considerations can be factored in to make certain kinds of failure a less-than-catastrophic affair.
"The moon's overrated. OK the golf is easy but the brochures all go on about the seas and as far as I can see when you get to the beach the tide's always way out ."
Oh, I don't know... I've seen lots of fotos of the Grand Canyon, and I've been to Carson National Monument in New Mexico, and I've driven through the desert in eastern Arizona; they're pretty desolate for sure, but man, are they gorgeous, and I'd certainly go back again if I had the chance.
For the same reason, I could totally get into a week's vacation at Hadley Rille or the Taurus-Littrow Valley. Hadley would be especially spectacular, I think, if the panoramas the Apollo 15 crew shot are any indication; imagine the Grand Canyon turned up to 11... or, perhaps the Taurus Mountains near the Apollo 17 site would be good for some stargazing -- guaranteed clear skies, y'know.
Too bad I've not done any mountaineering; I'll bet climbing the Tycho Central Peak would be awesome.
Yeah, I've got a "spatio-temporal cloaking" scheme for you, it also works by creating a gap where there aren't any photons where an event can take place unobserved, it's called "darkness" and I create it by switching off the lights.
Furthermore if you put your computer in my newly-invented "room with the lights off", you also can't see hackers attacking it.
Can I have my Nobel prize now please?
I was in complete agreement with you here but then I went back and looked at the diagram and I *think* I have the answer. In your method people can observe that something has happened (i.e. the lights went out) when your unobserved event takes place.
In the Cornell method an observer would not notice anything changing, so it's as if someone did something in a lit room which you could not see without them having to turn the lights off to stop you seeing it.
Hope that makes sense - I also hope I'm right because I'm actually a little bit embarrassed by how excited I am that I may have worked this out :)
What Alex is getting at is that observers can obverse that your event is unobservered.
The article is describing a situation where observers are none-the-wise about not observing an event. However, they may observe the feck-off big machinary that is preventing them from observing said event.
The point of a cloak - whether spatial or spacetime is not just to hide things or events, but to also hide the fact that they are hidden.
But rather than "Cornell method", I think you might mean "Imperial College London method" instead :-)
Some other links & commentary (by me)
Yes, the earth is a giant computer - but then some damn fool loaded a Trojan'ed update "because he wanted to see the boobie video" and now it is infected with Trojan-B-Ark. The mice are furious, and I hear they are taking us to the Galactic Worst Buy to let the Vogon Geek Squad "fix" it...
For example you imagine that by speeding and slowing the clock signal of a target system you can preserve its outputs unchanged from the unaffected case, but nevertheless create a time interval in which you can use the hardware undetected. But at the moment this is just a concept, not a suggested implementation.
only for the first few episodes it featured in & it was only supposed to be used in the gamma quadrant too, but that didnt stop the Defiant crew from using it in boththe alpha & beta quadrants multiple times often with the romulans finding out about the fact & yet the romulans never demanded the return of the device.
besides everyones forgetting the pegasus project ;)
OK, so let me get this right - if we bend light (or whatever EM radiation) around something so it can't be detected, then anything that happens to said thing (or that said thing does to anything else) then didn't actually happen simply because you still can't detect it?
Isn't this just the 2012 (said in either way) version of the noise falling trees make in a forest when no-one is around, or perhaps Schroedinger's dear/dead little moggie?
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"The team estimates the effect could be stretched to a single second, long enough to allow code injection"
- does that mean into a cable or directly into RAM, or what? It's too brief to understand.
If it's hacking a data cable then surly all the parities and handshaking will catch it and return an error.
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