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Comment Re:This will NOT break all encryption algorithms.. (Score 1) 318

Not to bust anyone's bubble, but the factoring problem is actually not known to be NP completely and evidence points to the fact that it is no, since if it could be shown to be then this would prove that NP=Co-NP. Similarly, the discrete logarithm problem is also not known to be NP-complete. Therefore, public key cryptosystems should be fine.

TL;DR - No encryption schemes will be broken if it is proved that P=NP.

You got that wrong. If P=NP, then NP=Co-NP, so your public key cryptosystems are broken. (Also, if P=NP, all problems in P are NP complete)

Comment Re:didn't it come from the states? (Score 3, Insightful) 69

According to the (slightly out-of-date) article, the whole of Europe sends less spam than the US. I'm quite sure there are more computers in Europe than in the US, as the population is more than 60% larger (only counting EU. The spam level in the article is likely about the whole continent, which has about 130% the population of the US), and the developement level is similar.

Comment Re:Generoators (Score 1) 328

The need of generators depends on where you live. I live in an area that is neither prone to floods, nor earthquakes, nor storms. We have a pretty stable grid*. During my entire life I can remember four blackouts, the longest lasted about two hours. So currently I have no need of a generator.

*This may change if photovoltaic and wind energy increase and the planned extension of the grid is delayed. But for now, it's sufficiently stable

Comment Re:Cool insight... (Score 1) 138

I believe that infinitely more insight on what the human body will accept and reject comes from clinical studies and research on implants then from art projects, especially those actually implant technology (i.e. try to connect technology to nerves). From a medicinal standpoint, this professor could as well have implanted a plastic globe.

Comment Re:In other words (Score 1) 517

The inflation in the Weimar Republic was stopped November 1923 with the introduction of the Rentenmark and followed by a period called "Golden Twenties", with a pretty stable currency and economy. I sincerely doubt that the mentioned inflation was a major cause for WWII. It may have played a role, but there were much more important factors.

Comment Re:*ALL* kind of alternative fuels? (Score 1) 108

A practical steam engine fuel has at least the requirements:
- high energy density (you don't want a tender full of grass clippings behind your car)
- maintenance free fuelling the burning chamber (you don't want to shovel coal)
- clean, low emission burn

So basically, you have to process most of your example fuels anyways to be useful. Processing them to anything a conventional diesel engine (or, if you really like ethanol, otto engine) can burn is not a significant loss of efficiency.

Comment Re:Waste Heat Engine (Score 2) 108

Well, the main reasons why otto and diesel engines don't reach the theoretical maximum efficiency of the otto or diesel cycle is that they lose energy to the cooling medium. If you could use some of that heat, you might close the gap between the theoretical maximum efficiency and the practical efficiency. The added weight will of course reduce the gain, but it still might be greater than zero.

Comment Re:240 km in THAT thing? (Score 4, Informative) 108

Speed Record Cars like this are usually build to run in a straight line on a salt flat. If you don't have wind from the side, there is no need for much stability. Building the car as narrow as possible reduces the area exposed to the wind and thus reduces drag.

Now if you try do drive that thing on a regular road, you'd probably not survive the first turn.

Comment Waste Heat Engine (Score 2, Interesting) 108

The Cyclone engine may be grat as a waste heat engine, i.e. to convert process heat back to some more useful type of energy. I doubt it's really usefull as primary engine, because converting fuel to heat and then heat to motion does not really sound more efficient than your usual internal combustion engine. And the main advantage "can burn all kind of alternative fuels"? Come on, I can do that with my diesel engine already. Increasing the efficiency of a car with a internal combustion/steam engine hybrid by using the waste heat of a combustion engine to gain some additional power could be a much better idea.

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