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Comment Re:fire! (Score 3, Interesting) 46

I would have thought similarly, but Wikipedia says otherwise (https://en.wikipedia.org/wiki/Aerogel). Perhaps a flame-front can't advance fast enough through a rigid structure?

Heat cannot spread through aerogels quickly, nor can the expanding hot air front spread further into the fuel, so I'm guessing only the outermost surface can be thermally catalyzed, and thanks to their incredibly low density there's not going to be a lot of other fuel within range of a burning molecule to absorb the energy before convection carries it away from the surface.

Comment Re:fire! (Score 1) 46

Has anyone actually managed to create a "vacuum-filled" aerogel? My understanding was that they were typically open-celled structures created by replacing the water in a gel with air. Though I suppose if the strength was sufficient you could encase it in an airtight skin and then pump out the air. That might have applications for rigid lighter-than-air craft, or as even more effective insulation. At least until a few days after a pinprick forms somewhere in the skin.

Of course the air can then be replaced by something else quite rapidly, giving them impressive absorption properties. Essentially they're an extremely low-mass sponge.

Comment Re:"you don't have to be very accurate" (Score 1) 127

I'm going with movie-knowledge. A nuke blast is only large compared to conventional weapons. Anything more than a few miles away from the blast will be virtually unscathed, and even much closer to the blast you're mainly talking broken windows and a bit of radiation damage. And hitting a relatively small and valuable target like a city requires precision aiming.

The only really credible threat from a poorly aimed nuke is a high-altitude blast, which would knock out radio communications and spread the fallout over a large area. Messy and expensive, but not really something that lives up to the visceral "Eeek! Nukes!" response.

Comment Re:High altitude nuclear EMP (Score 1) 127

The problem is not North Korea - we could destroy what little threat they pose to anyone other than South Korea today in a matter of days, if that. And doing so would probably

The problem is that China would hardly sit quietly by while we decimate their ally, and *they* are a major threat. For China, the continued existence of North Korea is the best of a lot of bad options. While a land buffer has less military value than it used to, they still don't really want the US to have a stronghold right on their border. Plus they spent a lot of lives defending N.Korea from the US during The War, letting the US win now would dishonor that sacrifice. Neither do they want to lose cheap access to N.Korea's extensive mineral wealth Nor to absorb such a populous and dirt-poor region themselves.

So China is stuck in a similar can-kicking position - they keep propping up N.Korea while hoping that someone more tractable comes into power.

Comment Re:If only... (Score 1) 221

I quite agree that my argument is based on stereotypes. But those stereotypes only have to be valid on average for the argument to be sound.

Would you really care to argue that geeks are, on average, at least as socially skilled as the larger population?

As for women who game the system, I'm not sure exactly what you mean by that, but I imagine even most of them would rather deal with the more socially sophisticated predators - I suspect such sophistication tends to make more profitable marks as well.

Comment Re:So what should we do? (Score 2) 452

Ugh, yeah, I hate those sorts of design decisions. I challenge the assertion that it's a brilliant idea though, except perhaps in a "sounds good in advertisements" way - there's a reason buttons tend to show up in groups, because individually they are an *extremely* limited interface.

You can't efficiently choose between more than two states with a single button - cycling is pretty much your only option without a non-trivial tap-code. And that means, on average, cycling through half of the states to get where you want to be. Multiple buttons can be used to reduce the problem by cycling through orthogonal options, or even offering a discrete button for each state.

Personally I prefer multistate switches: Twist the knob (or slide the slider) to the position that reflects your desire and be done with it. One single motion chooses between several options, and once you establish muscle-memory you can achieve precise results as soon as your hand finds a single control, even in complete darkness.

But sadly cost is typically a high design priority, and buttons are usually cheaper to integrate into a device than multistate switches, and the fewer the buttons the cheaper. Which leads to cool-sounding ad copy being used to spin cost-cutting compromises into slick-sounding "features"

Comment Re:Huh? (Score 1) 69

And so it will. 3D printed blades may well eventually be stronger and lighter than molded versions. But not today, when 3D printing is still in its infancy.

Just like when transistor radios first came out they couldn't hold a candle to a proper vacuum tube radio. They were radically smaller, lighter, cheaper, and more durable, and basically created the portable music market, but they lagged far behind in the most important feature of the existing radio market: sound quality.

Or maybe not . Even today vacuum tubes are superior to transistors in some applications. Just because a new technology is superior in most respects doesn't mean that here aren't areas where it just can't compete the old technology. And material science is one of those fields where 3D printing may never be able to fully compete. That doesn't mean it can't be strategically coupled with older casting and machining technology to reach heights neither technology could achieve on its own.

Comment Re:If only... (Score 3, Insightful) 221

Perhaps it is a matter of degree? Consider:

People who dedicate themselves to the science and technology fields tend to be somewhat lacking in social graces, prone to "blunt instrument" conversational skills. Contrast that with other fields, especially in management, where "people skills" tend to be some of the most valuable assets to acquiring positions of authority.

I would imagine that the inappropriate socialite boss is more likely to be skilled at "not crossing the line", gauging their victims tolerance for their unwanted advances and backing off before things escalate to the point that might drive them away or invite repercussions. Contrast that with a geek attempting the same thing - for the same level of inappropriate intent, most will be far less graceful about pursuing their goal, which is likely to make things more unpleasant for the victim. Up to and including the issuing of ultimatums where a more skilled predator might bide their time or seek less recalcitrant prey. I know which predator *I* would prefer to have to tolerate every day.

And then of course there's positive feedback aspect which doesn't create the problem, but does intensify it: sci/tech are currently abnormally male-dominated fields, which means there's likely a higher ratio of predators per woman. That would tend to make the fields less appealing for women even if predators were no more numerous or unpleasant among geeks than in the general population.

Comment Re: Intel (Score 2) 136

True. It seems that AMD learned their lesson when they held the performance crown - while they might be able to outcompete Intel on raw performance and affordability, they'll never be able to afford to compete against Intel's dirty tricks and anticompetive behavior. So instead they target the mainstream and console market, and let those who are actually interested in the price:performance ratio to come to them.

Comment Re:Anything the US does is suspicious (Score 1) 283

> maybe it's time for the US to be rash and unstable for a change, see how everybody feels about that

I have a feeling that would go *really* badly for us. NK is fairly irrelevant to most of the world - they make a lot of noise, and could *maybe* drop a nuke somewhere if they were willing to be wiped from the face of the Earth, but otherwise aren't a credible threat to anyone other than their immediate neighbors.

The US however is the largest single military threat in the world, and thanks to our aggressiveness in the last decades we're beginning to see substantial military and economic alliances form against us. If we went irrational as well as rogue we'd probably find those alliances against us becoming much stronger, as well as losing a lot of our current allies. And while we may have a strong military, we're not in any position to take on a substantial portion of the world.

Comment Re: Anything NK does is suspicious (Score 1) 283

Agreed. I think a lot of the comparative military philosophy is actually expressed in the traditional war games of our respective civilizations. The US has chess - straightforward, highly tactical, with just enough room to manage the occasional sneak-attack if your opponent isn't paying attention. By contrast the orient has Go - highly strategic, incredibly subtle, and the whole tide of battle can shift in an instant without you even noticing if you don't see deep enough into your opponent's long-term strategy.

Comment Re:Unearned Platforms Given to Moral Guardians (Score 1) 238

Hell, as a red-blooded, woman loving man, *I'm* annoyed by a lot of the sexism in games. If I want to watch porn, I'll go watch porn. If I'm playing a game I want an immersive and plausible world, one where half the characters aren't puerile appeals to adolescent hormones dressed in skimpy armor that would likely get them killed the first time they entered combat.

Comment Re:Mars is impossible (Score 1) 310

Yes. Mars has the resources necessary to pull off a relatively low tech steady state and growth. There will, for a while, be a need for high-tech components and material from Earth. Maybe for as long as a century or two, almost certainly for at least a couple decades. Water and CO2 being the big ones, though sources for other trace minerals will be needed. Once you have a thriving ecosystem you have raw materials for almost everything else you need (for example google nanocellulose, very impressive stuff). Beyond that you'd mostly need power sources. I'll admit that could be a challenge. You're probably not going to make solar cells too easily without relatively sophistcated tech, but fission? Maybe. That's really relatively low tech when you strip it down to it's most basic requirements.

The moon... there's no such guarantee. From what we've seen so far it seems like some of the really important things like water are effectively missing. We could eventually make it from oxides and hydrogen deposits, but that requires much more sophisticated technology than just sucking or slicing it up, as well as more far-ranging transportation. Might be doable, but you'd be riding a lot closer to the edge.

You make a good point about telepresence for initial development, I hadn't really considered that, but I think you'd find even the 2.6+ second feedback delay to be far more difficult to compensate for than you might initially expect. There would be no direct control of robots for tricky tasks unless you could manage it very slowly. They'd have to handle all the dexterity and reflex components autonomously, and you'd have to learn to work within the constraints of their imperfect anticipation of your intentions.

Comment Re:Venus (Score 1) 310

Actually, high-efficiency solar panels are approaching 40% conversion efficiency, so you'd only need about 6x the area of solar panels to provide earth-equivalent lighting on Mars. And presumably shade-loving plants would be quite popular. Also, fission reactors don't have to be particularly heavy - the Russians have made a fairly efficient model designed to work equally well on in space or planetside, though I can't remember the name. Something about lots of nested metal shells if I recall correctly.

Okay, I had a feeling that it was Earth's atmosphere blocking most of the radiation, and the magnetosphere mostly protects the atmosphere from being stripped away by the solar wind. Which is dangerous in its own right, but isn't going to make it very far through an atmosphere. 8CT scans a year is nothing to sneeze at though. It may not kill you directly, but just two abdominal CT scans, with and without contrast, are considered to pose a moderate cancer risk. Whatever that means in real terms like expected reduction in life expectancy.

If light levels are comparable to Earth that is indeed very promising. The lightning storms though, from what I had found the little data we have suggests that ambient levels are comparable to a violent Earth thunderstorm. Perhaps we'd get lucky and they could be avoided, but it seems unlikely to be 100%. And considering the fact that we're roughly in the middle of the cloud layer, it seems naively optimistic to think the slight variations in altitude we could achieve without either freezing or cooking would somehow avoid a conveniently narrow electrically active layer.

And I'm not sure it's possible to make a faraday-caged balloon that can handle lightning-bolt amperage and still be light enough to float. At least not unless you scaled the thing up to huge levels. Though perhaps running the numbers would look more promising, especially if using something like a highly conductive graphene skin. Perhaps if coupled with an ion shield so that most of the current would flow through the ionized air rather than the conductive skin... but the skin is probably going to be a far more attractive path, at least until it vaporizes.

Still, well worth gathering more data to assess viability.

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