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Comment Re:Higher voltages (Score 2) 146

Really??? So if I connect two (super)capacitors in series, thereby doubling the voltage limit, I have somehow squared the energy storage!

You've also halved the capacitance and doubled the volume. So: twice the voltage (4x), half the capacitance, (0.5x), and twice the volume (0.5x). Looks like your energy density didn't materially change.

Comment Higher voltages (Score 4, Informative) 146

Well, yes, the amount of energy stored goes up as the square of voltage for a given capacitance. However, for a given dielectric getting twice the voltage requires twice the thickness and cuts the charge in half -- so the energy per unit volume is unchanged.

Which shouldn't be surprising since the energy is stored in the dielectric by (e.g.) straining the molecular structure of the material.

The biggest reason for going to higher voltages is to reduce the interconnects, which get enormous at low voltages and high currents. (Cross-sectional area goes up inversely with the square of voltage for any acceptable IR loss, which is why long-distance power lines run at scary voltages.)

Comment Re:WHAT radioactive materials? (Score 1) 242

Secondary radiation, however, is a different matter. And someone said that the fusion was only a source of neutorns to enhance fission. (That seems like a pretty wierd idea, since we don't currently have fusion working.)

Hate to break the news, but bog-standard fission bombs have been getting a boost from fusion-generated neutrons since the 50s (maybe 40s -- I don't feel like looking it up ATM.

Comment Declaratory judgment (Score 3, Informative) 30

There's a mechanism in US law to deal with this kind of thing. It's called a "declaratory judgment," where a plaintiff who has reason to be afraid that the law will be enforced to land him in prison or bankruptcy sues for a judgment that either the law doesn't forbid his (in this case) publication of his research or that the Constitution forbids a law that would. Yeah, such suits ain't cheap. Fortunately there are several nonprofits that exist to fight exactly that kind of battle.

Comment Re:ABC Anywhere But China (Score 5, Informative) 236

Key difference: the Chinese don't, generally speaking, have the power to kick in my door here in the USA (or for that matter in most places outside of China). The USA has, on the other hand, demonstrated both the ability and willingness to vanish people to "black sites" without any regard for what most people would recognize as due process.

Talent does what it can. Genius does what it must. You do what you get paid to do.