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Comment Re:shipping java scientific software for 15 years (Score 1) 577

Not just can be, it usually is faster. At least, once it's been JITed. We just ran some XML serialization/deserialization tests, and the java implementation was much faster than the C++ one...eventually.

What about pure numerical stuff? I'm wondering how say, a Java implementation of FFT would fair against the FFTW library (coded in C).

Of course you could make a native call to the FFTW library (MATLAB does this) through Java, but thats missing the point.

Comment Re:Countries do this all the time (Score 3, Insightful) 245

Countries prepare war games involving invasions to or from nearby countries all the time.

True, but Switzerland takes it up a level. Permanent tank traps in farmers fields, hidden military installations all over the country, bomb shelters, and a huge military reserve with regular training.

All purely defensive measures, which for a small country that hopes to repel potential invaders, while retaining their neutrality and not having rely on "allies" to bail them out, seem pretty reasonable.

Comment Re:Great, let's send plants (Score 1) 247

Magnetism, actually. The magnetosphere (all the best names have been taken by old discoveries, btw) keep solar winds from stripping away the atmosphere of a planet. That and, you know, gravity to keep the air stuck to the surface.

OTOH, you have Venus, whose atmosphere 100x denser than that of Earth despite having almost zero magnetic field.

Comment Re:why not start smaller? (Score 1) 533

Unless you willing to go underground, there's no where to build it, and they already a rail line from SJ to SF - CalTrain. The bullet, which has ~5 stops between SJ and SF takes ~1 hour. Yes, they could improve on this, but its not worth it. SJ to SF is more of a regional system where you are going to have to stop frequently anyway, in order to get enough passengers

  I don't think there would be enough traffic to justify a SF to Sacramento only route.

Comment Re:Mars and Venus are warnings (Score 2) 137

Venus already has a really effective 'shade' - the bond albedo (percentage of light from the sun it reflects) is 0.9 (90%). Compared to ~0.3 for Earth

Venus is so hot at the surface mostly because the atmosphere is incredibly dense at the surface (93 times earth). In geneneral, as pressure increases in a planets troposphere, so does temperature. If you go deep enough into the gas giants (even Neptune), you will find very hot temperatures, at high pressures.

On Venus at 1 bar pressure, the temperature is actually not that far off of Earth - (about 50 C = 122 F), hot, but not unmanageable if we could somehow put a floating colony there. You would have to seal the habitation anyway because the atmosphere is about 95% CO2.

Comment Re:Not a gas-hybrid (Score 1) 222

Uany economist will tell you its the used car market that seriously hurts our fossil fuel numbers, currently the USA averages 14MPG and that is because of all the poor folks in used cars on the road.

No, its because of all the trucks, SUVs and otherwise inefficient cars on the road. I just bought a used 1996 Toyota Carolla with 230k miles on it. I checked my gas mileage (mixed city/freeway) at 26 MPG on my last fill up.

My friend who drives a 2008? BMW M3 told me gets 23 MPG.

Comment Re:But for Terraforming? (Score 1) 264

Issues with removing the atmosphere aside:

1. I'm pretty sure that Venus doesn't have an appreciable magnetic field.

2. Even if it did, its day is about the same length in its year (e.g. about 250 earth days) so nobody could live in any fixed place on the planet without freezing or melting, even if we got rid of the thick atmosphere. You'd have to live in trucks rolling slowly around the planet in the ... pardon the pun ... twilight zone.

On Venus, there is actually very little difference in day/night temperature, at least near the surface - it always around 450 C (~860F, hot enough to melt lead). There is also little variation at the poles and equator. Very little incoming solar radiation reaches the surface. This is combination of very high albedo (0.9 bond) and greenhouse effect. Of course, this is not the case with the upper atmosphere where temps and pressures would be more Earth like. That would be among one obstacle for a 'city in the clouds' idea.

Every cloud has a silver lining; you should have sold it, and bought titanium.