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Comment Re:Open source win (Score 1) 306

information theory
You probably mean "cryptography". Information theory is related but different.
Anyway, cryptography makes a distinction between "obscure" and "secret". The idea is that good cryptography requires a secret. If something is in your possession (like a program on your disk), it's not secret to you (exception could be made for some secure chips that are designed specifically so that you can't read their secret).

Comment Re:cool story bro (Score 1) 254

> How sensitive would a device have to be, and how fast would it's
> processor need to be, to detect a 10mph difference from the
> frequency of a radio signal coming from space I wonder?
Well, GPS works at about 1GHz; I think we can assume that a GPS receiver can count the number of cycles.
10mph vs speed of light is about 10^-8, meaning about 10 cycles difference in a second. Seems measurable (GPS also provides very accurate time measurements; there might also be possibilities of measuring interference between signals from different satellites). The link I gave indicates an accuracy of about 0.5mph using a combination of doppler shift and location change measurements.

Comment Re:cool story bro (Score 1) 254

Interesting.
Either way, the fact that a given position is off doesn't really imply that the speed is wrong (as long as the position is consistently off).
Also, it's the first time personally that I've said that, and there is obviously reason to think that some GPS receivers do use the doppler shift, so please don't be so mad.

Comment Re:Stupid Idea (Score 1) 1026

High Speed Rail would have the EXACT same security measures as airplanes, except they would be even less safe as blowing up track is easy, especially when you have hundreds of miles to choose from.
How do you explain that, in the countries that have high speed rail, the airport security is the same as in the US but there's no such thing for trains?
Bombing a plane is already not the most effective way to kill people, it's mostly for show. Attacking a subway would still work better than attacking a high speed rail (or low speed rail for that matter, I don't see why that would make a difference except for popularity, I guess)

Comment Re:Awesome if it works (Score 1) 416

> That weird concept of "throwing away your vote" when the person you voted for doesn't win is probably one of the biggest things wrong with our voting system
In technical terms it's called "independence of irrelevant alternatives". It doesn't work in most voting systems.
http://en.wikipedia.org/wiki/Arrow's_impossibility_theorem

Comment Re:Probably Wrong but Clearly Falsifiable (Score 1) 700

In fact it does suffice to show that the algorithm determines satisfiability of a 3-SAT instance in polynomial time.
Really? I have an algorithm that can solve a 3-SAT instance in constant time.
Algorithm:
if(problem == "true") then "satisfiable" else "failure of classification"
"true" is a 3-SAT instance with no variables

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