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Comment Re:Not really. (Score 1) 359

Actually, yes, it does. There's also a web page written by a fusion researcher featuring that graph and it gives a good, accessible rundown on the progress that's been made to date and a good projection of what still needs to be done.

Keep in mind, IIRC, those projections were made in 1976. It wasn't "we need more money" it was a set of recommendations for the US to decide how aggressively to pursue fusion research, from Manhattan project level to "you might as well not even bother."

Comment Re:A step forward, but... (Score 1) 359

Suppose we're using a two stage reaction:

D + D -> 3He + n + 3.27 MeV
D + 3He -> 4He + H + 18.3 MeV

That gives us 21.57 MeV = 3.5e-12 J per 3He atom. World energy usage is 6.0e20 J.

To supply that, assuming we have a 100% efficient reaction, we'd need to produce 1.6e32 4He atoms, which is 2.7e8 mole, or 1.0e6 kg

A standard 11" balloon apparently requires .015 m^3 of helium, which is about 2.7 g. So we could inflate about 400 million balloons. Incidentally, they could lift about 4000 tonnes.

Unless I made a mistake.

Comment Re:Mission accomplished (Score 2) 359

It's good to have options. As you say, wind and solar are doing just fine. They're today's technologies. Fusion is looking promising. It's the technology of tomorrow. The power density, self containment and controllability of a practical fusion reactor lets you do things that wind and solar can't.

Comment Re:Wait, physics doesn't work either? (Score 2) 206

You're mixing up generally irreproducible results and a situation where a proportion of reported results are not replicated.

Modern psychology is very much a science, using the scientific method. However, due to the difficulty of studying it, the requirements for publishing a result are low enough that many of them turn out to be incorrect (not reproducible). That these results are eventually found to be incorrect is a validation of the scientific nature of psychology.

ANY subject involving a complex, difficult-to-study subject is going to have the same problem. Most fields like that, psychology, medical science, ecology, systems biology, etc., prefer allowing reasonable sized studies (usually less than a few million dollars) to be published, knowing that they may be incorrect, then replicating the interesting ones. Particle physics has tended to go the opposite way, where high profile results are not published until the confidence is very high, but those results also cost billions to achieve. Lots of less high profile results are, of course, held to lower standards.

The real lesson to take from the problem of replicability is not snide "psychology isn't a science" but rather that being published in a journal (hopefully) means that the study was done in a scientific way, but is no guarantee that it's true.

Comment Re:Wait, physics doesn't work either? (Score 1) 206

Your "underlying state" seems equivalent to a "hidden variables" theory. Note that the Bell inequality says that if the universe is local (no action at a distance, special relativity, etc.) then hidden variable theories cannot reproduce the observations of quantum mechanics.

It's possible the universe really does have a deterministic nature that is hidden from us, but if that's true then the laws of physics are not local. We tend to shy away from that option because of the success of special relativity, and prefer the other: that the universe really doesn't have a deterministic underlying reality.

Comment Re:Wait, physics doesn't work either? (Score 1) 206

I think the answer is "we don't really know." One of the criticisms of the standard model is that, although it has fantastic predictive ability, it doesn't have much explanatory ability. It can't even tell you something as seemingly simple as why an electron has the rest mass that it does.

However, you might find the phase/state/configuration space formulation of quantum mechanics more intuitively satisfying. You can imagine a quantum system as being a particular state space with rules restricting how you can move.

Maybe some new developments, such as the holographic hypothesis, will provide more explanatory power.

Comment Re:It can't. (Score 1) 102

It doesn't have to be something as large as that. Much smaller impacts throw up material from rocky planets that can seed the solar system. Escaping the sun would be a bit harder, but it could happen via occasional very large impacts, or comets being seeded by small impacts and then ejected from the solar system.

Comment Re:So then the question becomes (Score 1) 440

There's no persuasive evidence to indicate that Ashely Madison didn't fake female profiles. There IS evidence they faked profiles. Assuming they were only female seems a bit biased, no?

Note that your objection about fake profiles not chatting doesn't really hold up. Fake female profiles also don't chat. The idea is to keep presenting pictures and profiles that you like, to keep the hope alive.

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