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Comment Re:hu-person-made surely? (Score 4, Interesting) 63

No, that's not it.

Sorry but you are wrong. In old english 'man' meant person without any gender specification because 'wer' meant male human where is where "werewolf" comes from: literally "male person-wolf". However because we started to use the word 'man' to mean male human this interpretation has now been retroactively applied to words which were derived when the meaning was gender neutral.

And for what it's worth, for all of the complaints given about the US, the US is perhaps one of the least male-dominated societies out there.

Seriously? So how many female government leaders have you had? Your congress has under 20% women compared to ~25% for Canada, UK and Australia and 30% for New Zealand. Even Saudia Arabia has a 1% higher proportion of women in its national parliament than the US. In many European countries the ratio is in the upper thirties to forty percent.

Comment hu-person-made surely? (Score 4, Insightful) 63

Not in the politically correct portions of Northern Europe.

Which is ironic since the use of 'man' to mean 'person' in English comes from German where 'man' means 'one' and 'Mann' means man. So man-made actually means 'person-made' not made by a male. So instead of making the language clunky perhaps we should just educate people as to what it really means otherwise next we'll end up having to use 'huperson' instead of 'human'.

Comment Re:Failure modes (Score 1) 144

We use capacitors all over the place and most of the failures of them are demonstrably not from catastrophic discharge.

Large capacitors which store significant amounts of energy or the tiny ones in circuits? Particle physics bubble chamber experiments in the 1960/70s used to have magnets which were pulsed by capacitor when the beam hit them. The stories I've heard older colleagues tell about accidents involving the massive capacitor banks suggest that sudden, catastrophic failures can and do occur. With a small capacitors you get a puff of smoke, with massive capacitor banks you get people blown across rooms and seriously injured.

Comment Not the only fraud... (Score 0) 319

Here, fraud presents itself quite naturally and they can't seem to find it.

Perhaps they are worried that the US government could be charged with fraud too since it seems they passed an act which they said would make it illegal for car manufacturers to make highly polluting cars but which, it appears, does nothing of the sort.

Comment Not at all gracefully (Score 2) 144

Cellphone batteries are already pretty scary when punctured, imagine something holding several times as much energy.

One of the problems with capacitors charging rapidly is that they can also discharge very rapidly too so any failure would not be graceful. However I'm not sure there is much reason to be optimistic yet for these devices. The article mentions that the way they get high voltages is by connecting the capacitors together. This means they connect them in series which will significantly reduce the actual capacitance since capacitors in series add like resistors in parallel.

Comment You do need a clock! (Score 2) 106

You do not need a clock to determine longitude.

Yes you do. Maskelyne's method just uses the moon as a clock and required being able to accurately measure the angular separation between the moon and a bright star near its path to determine the time. Since the moon moves ~0.5 degrees every hour you need to measure the angle to at least this accuracy to get a time. While it worked it required great care measuring the angles, complex tables to convert the angle to a time and a clear view of the night sky. Even with all this extra effort on the one voyage where they were compared directly this method produced an error three times greater than Harrison's clock.

I would also disagree with your open tech argument. Have a look at the 1775 Nautical Almanac. Apart from copyright on the tables you had to have a government license to print them and the calculations on which the tables are based are not given anywhere (although there is some reassurance that the calculations have been checked multiple times). Worse this is a something you had to purchase every year. I don't see how this is any more open than Harrison's clock whose mechanism you could examine and tweak if you though you could do better.

Comment They were built in the 1700's (Score 3, Informative) 106

If the clock could be produced using 1700's machining and metallurgical technology, only then would it prove Harrison's contemporary critics incorrect.

Harrison built his clocks in the 1700's (although apparently Slashdot only just heard about it). They were incredible machines for their time and, after much wrangling with the astronomers of the time (who thought that schemes like making detailed observations of the moons of Jupiter through a telescope on the heaving deck of a ship in the mid-atlantic were better ideas) he won 1700's X-prize equivalent for inventing a machine to accurately measure longitude. You can actually see the clocks he made in the old Royal Greenwich Observatory building in London.

Comment International Collaboration (Score 1) 211

An even better idea would be to do it as an international collaboration - but a real international collaboration based on international treaty (like CERN) not a US-controlled project with other partners (like the ill-fated SSC). Not only do you share the costs but it might also help to reduce the need for those F-35s.

Comment Re:Neutrino Radiation (Score 1) 191

Taking your interaction rate without question a trillion is 10^12. The LHC has several orders of magnitude more protons than that in each beam and remembering that muons decay it seems entirely reasonable that a muon collider would probably need even more to have the same number of particles. Even one interaction could be serious at these energies since it will shatter a nucleus and create a shower in the body however the rate would more likely be hundreds per second given the same particle counts as the LHC.

The threat was bad enough to be seriously considered: see this paper.

Comment Tortuous Logic (Score 1) 127

Not quite - doing the research required to know how to blow up the moon and then telling everyone how to blow it up is apparently what this guy thinks is protected. The tortuous logic is that activities required for communication are protected and, before you can communicate scientific knowledge you have to have found that knowledge and so therefore scientific research is protected.

This is clearly nonsense. You can communicate scientific ideas freely without knowing that they are right. Indeed this is what a lot of scientific discussion is - exchanging ideas about how things might work and then designing an experiment to test the hypothesis. As with everything else the speech should be protected, acting on that speech, i.e. research, should not.

Comment Neutrino Radiation (Score 3, Interesting) 191

but the short lifetime of the muon has kept anyone from coming up with a workable proposal so far.

The other problem they had with the muon accelerator proposals which Fermilab looked at a while ago was the lethal amounts of neutrino radiation from muons decaying. While neutrinos rarely interact at energies below a PeV if you get enough of them there can be enough interactions to be dangerous if a human stood in the beam and unfortunately shielding really isn't an option with neutrinos.

Every nonzero finite dimensional inner product space has an orthonormal basis. It makes sense, when you don't think about it.