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Comment: Re:perception (Score 1) 274

Charities are more direct and people know that it is being done because people actually care, not because their funds have been confiscated under threat of imprisonment.

The problem with relying on "more direct" charities is that far too many people fall through the cracks of a heterogenous crazy paving of such organizations. Conversely, it also tends to be easier for con-artists to prey on such scattered organizations.

Comment: Re:power cars? technically no (Score 2) 147

by tragedy (#46776765) Attached to: 'Thermoelectrics' Could One Day Power Cars

A detonation doesn't neccessarily release more power than a deflagration. That's apples to oranges. It's more a matter of intensity. For example, ANFO detonates, and has a specific energy of something like 3.7 MJ/kg whereas a gasoline/oxygen mixture in an engine typically deflagrates (although it can also detonate under the right conditions, which isn't good for the engine, as you point out) and has a specific energey of something like 9.7 MJ/kg (counting the gasoline plus the oxygen needed for combustion). Clearly averaged over time you can get more power out of an equivalent mass of gasoline/oxygen than from ANFO. Although, if you slice time thinly enough you can say that you get more instantaneous power out of the ANFO because you can get all of the power out of it faster than you can from deflagrating the gasoline/oxygen mixture.

Comment: Re:power cars? technically no (Score 1) 147

by tragedy (#46776675) Attached to: 'Thermoelectrics' Could One Day Power Cars

2. Supply isn't as big a problem as the incredible safety issues. I acknowledge in my post that the idea is totally insane, which is why I doubt that, even with a big improvement in efficiency, you'd probably never see RTGs used outside of military applications.

The safety issues aren't really that bad. You could put 60 kilos inside a casing that would easily block the radiation down to negligible levels and would be effectively indestructable in the worst conceivable accident. Worries about "dirty bombs" are ridiculous considering the large array of easily available substances that would be much more dangerous (not very) in such a bomb. As for a nuclear weapon, I'm not exactly sure how fissionable it is, but I do know that you would need a massively powerful nuclear weapon in the first place in order to actually induce fission in it, so it's not dangerous in that respect either.

So, right now, the supply probably is the biggest problem. At the rate the US is currently producing it, it would take 40 years to get enough for one car. Not that the rate of production couldn't be ramped up considerably, but it would still be so expensive it would only be useful for powering things in space or at the bottom of the ocean, or deep under the earth, etc. Places where power is otherwise impossible or incredibly expensive to obtain.

Comment: Re:power cars? technically no (Score 2) 147

by tragedy (#46776637) Attached to: 'Thermoelectrics' Could One Day Power Cars

1. Current TEs are no where close to 50% efficient. More like about 5%.

The article was about new, higher-efficiency materials. Still not high enough, and not near 50% efficiency, but certainly getting up there. Good enough so that, if you could get hold of the material, you could at least use it to charge your electric cars batteries currently, even if you couldn't power the car directly. Of course, at present, you'd be better off with a Stirling engine.

3. You can't "turn-off" an RTG. They have to run continuously.

Presumably, you could plug them into the power grid in most places you park them

Comment: Re:Stop Now (Score 1) 172

by tragedy (#46762573) Attached to: Cost Skyrockets For United States' Share of ITER Fusion Project

And my point is that these are essentially status projects. Well, the NASA one is a reused status project. Spending a lot more money than you have to is part of the project.

Which NASA project? Are you talking about the Space Power Facility? That's not a prestige project, that's a giant bell jar with really good vacuum pumps. Even though it looks cool enough to be used as a movie prop/set, it's very utilitarian. As for those giant tents, they may be prestige projects, but that doesn't really mean anything. Large utilitarian projects intended as nuclear experiment stations also are built at a premium because they're meant to be built to very high standards.

For example, I believe an inflatable structure of the appropriate scale with a medium vacuum in the center and properly anchored to the ground (or perhaps rather the inside of an abandoned open copper mine) could be had for low tens of millions of dollars (the inflatable components of the outer shell would be moderately over-pressurized cone-shaped wedges which would need to resist one atmosphere of pressure and wind loading with appropriate factor of safety). That includes building of smaller structures to get the many design issues worked out. That's not quite good enough a vacuum, but it's getting there.

If you're going to build a truly massive vacuum chamber on the cheap, then you can probably build it somewhere like Fall River Pass in Colorado so that you only have to hold off .65 Atmospheres of pressure, although I don't know if there are any suitable pre-existing depressions around there that you can use. Honestly, your plan sounds pretty neat and is probably practical. The problem is that inflatable vacuum chambers are still a pretty novel technology. So, you would be basing one highly experimental project on another highly experimental project.

The space experiment is also an interesting idea. I personally wish we lived in an environment where this kind of research could be done, with the recognition that the potential returns are vast. That's not what we get however. We're lucky to get ITER and they're already grumbling about the cost and fudging the numbers to try to kill support. After all, this whole article is a sensationalist bit trying to claim that the actual cost of ITER has gone way up when, if you read it, it's evident that what's really happening is that the long-term cost is going up because they're not shelling out the money in the short term.

Comment: Re:more pseudo science (Score 1) 850

See. This is the sort of thing I find really strange. I remember taking a geology course where the professor explained all about the various layers to be found in dirt that develop naturally over thousands of years... then pointed out that we would be very unlikely to ever actually experience those layers in the real world because there's so little dirt in the world that hasn't been turned over by human beings. There's only about 5 acres of land per person on the planet. That's just the people, consider how how much manufacturing waste and resource use and pollution there is for every one of those humans. Consider how long it persists compared to a human lifespan. It's truly baffling how anyone could think that our ability to change the world with our activities would be small.

Comment: Re:more pseudo science (Score 1) 850

That's really, really missing the point. It's not as if we've studied _every single_ mouse birth that has ever occurred to make sure that not a single one of them spontaneously popped from a donkey hide or something like that. The point is that of the two groups: denialists and actual climate scientists, the climate scientists actually practice real science, continuously researching and experimenting and challenging their own ideas and the denialists tend to just be sophists. As I said, I'm probably going to bet on the side of the legitimate researchers rather than a bunch of people who tend to scoff indignantly at the very idea that man can alter the environment despite the massive evidence that we really, really can.

Comment: Re:Stop Now (Score 1) 172

by tragedy (#46744975) Attached to: Cost Skyrockets For United States' Share of ITER Fusion Project

A prototype would only be a portion of the development costs. The private world would foot most of the bill, assuming that economically viable fusion reactors were demonstrated.

Which is what ITER is supposed to do. Demonstrate that it's possible to make a commercially viable fusion reactor and work out the problems involved in actually doing that.

These are prestige projects. They wouldn't build them, if the design were cheap. Another example, is the Khan Shatyr Entertainment Center [wikipedia.org] in Astana, Kazakhstan. It's a 150m high tent structure which supposedly cost $400 million to produce.

But the point is that these structures are essentially _tents_ and they're a small fraction of the size of the "very large Farnsworth fusor or polywell device, say hundreds of meters in diameter and a few modest free-electron lasers to illuminate portions of the fusing plasma" that you suggested and are still very, very expensive. The construction methods for a device such as you suggest would need to be a lot more robust and would be an order of magnitude more expensive. Since they would also be a _lot_ bigger, it's hard imagining such a project not being in the same budget neighborhood as ITER.

I agree with you on some of the other points. The miracle right now is that any money is being spent on fusion research. Frankly, looking back on the long history of ITER, it's amazing it's moving forward. It's clear that it couldn't have gotten anywhere with just one country supporting it. Not the United States, anyway, which keeps running hot and cold on the project.

Comment: Re:The President doesn't micro-manage this stuff (Score 1) 134

by tragedy (#46741915) Attached to: Obama Says He May Or May Not Let the NSA Exploit the Next Heartbleed

That depends heavily on what you mean by an advantage in cyber war. If you're after mutually assured destruction, then maybe patching holes in everyone's defenses doesn't help. If you don't want your own side to be completely destroyed, it's aterrible idea.

Comment: Re:Stop Now (Score 1) 172

by tragedy (#46738609) Attached to: Cost Skyrockets For United States' Share of ITER Fusion Project

Obviously I should have said: "working fusion reactor highly into the net positive side". I thought it was understood in context.

So we're going to make a hundred thousand fusion reactors?

No, but that doesn't magically make the development costs cheaper than a well-understood consumer machine of which literally billions have been mass-produced.

They could have done that with a very large Farnsworth fusor or polywell device, say hundreds of meters in diameter and a few modest free-electron lasers to illuminate portions of the fusing plasma.

The millenium dome is 52 meters high on the inside and cost a more than a billion dollars and it's basically a giant tent. NASA's Space Power Facility is more the sort of thing you would need for a giant Farnsworth fusor. It's still only about forty meters high. I can't find exact costs for it, but I can guaranty it wasn't cheap and it's only a small fraction of the scale you're talking about.

Maybe your approach would be better. Who am I to say. This is what they're already building. I personally think it would be great if they could find the budget for a few different approaches.

Comment: Re:more pseudo science (Score 1) 850

For literally a thousand years people were going around profoundly claiming in tones of authority that baby mice spontaneously appeared through magic. All it takes is throwing some mice in a cage and, unless you're unlucky and get all males or all non-pregnant females, you can verify that this isn't true. The kind of idiotic sophistry that leads to spouting off "wisdom" without the slightest bit of decent research is to be abhorred. The climate researchers, by and large, appear to be doing their due diligence. The denialists, by and large, do not. The climate researchers very well may be wrong. I think, on balance, they're a much safer bet than the people who tend not to understand basic physical principles and who seem to mostly hold an essentially superstitious belief that humans can't alter the world around them.

Comment: Re:more pseudo science (Score 3, Informative) 850

You're confusing sophistry with science.

Spontaneous generation comes to us by way of Aristotle. It was finally challenged by the emerging field of science.

Lamarckian inheritance was not borne out by empirical evidence, so was effectively discounted. Modern understanding of genetics does recognize some mechanisms that resemble Lamarckian inheritance.

Miasma is an ancient greek magical revenge curse. Emperical scientists like Ignaz Semmelweiss worked away from that idea. For his trouble, he ended up dismissed from his position and replaced by Carl Braun, who stopped the handwashing program Semmelweiss had started and introduced a ventilation system to extract miasmas. The death rate went back up by an order of magnitude from when Semmelweiss was in charge.

Bloodletting goes back to belief in the four humours, which comes down from Hippocrates. Science is what has partially dispelled these ideas in modern times.

Aether is the fifth of the traditional Greek four elements. Once again, the idea comes down from fairly non-scientific thought. The name has cropped up to describe a number of different concepts in science, generally to describe something that may fill the universe in spaces in between regular matter. Science has mostly ruled out most of those theories. The general idea still lives on a bit in concepts such as the quantum foam.

Java Man... You've really got us there. A scientist dug up fossils of ancient hominids and... um... what's the smoking gun supposed to be there?

The universe seems neither benign nor hostile, merely indifferent. -- Sagan

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