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Scientists Say Their Giant Laser Has Produced Nuclear Fusion

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Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#51

Post by mike_esspe »

fophillips wrote: post #24
JackFr wrote: post #13

Earlier quoted context omitted.

Is this even basic science? It sounds more like an engineering problem, albeit a very hard one. I am not a physicist, but I would consider this more like the Manhattan project -- the science being done is not of the 'deeper under standing of nature' type, but rather 'how do you make a controllable explosion' type. Given that, the way to evaluate the project is not on grants received, articles published or citations i…

You go tell Feynman the Manhattan project wasn't about science.

From "Los Alamos from Below" by Feynman:

"What was happening, of course, was that all the boys had decided to work on this and to stop their research in science. All science stopped during the war except the little bit that was done at Los Alamos. And that was not much science; it was mostly engineering."

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#52

Post by deletes »

JackFr wrote: post #13
dj-wonk wrote: post #5

This sentiment is interesting "Over the past few years, NIF has been getting a fat 'F.'" Perhaps now that 'grade' will change. Actually, I think framing it as a grade is beyond silly; it is irresponsible. Giving a letter grade to long-term scientific project makes little sense. It is not a one-shot thing with a predefined notion of correctness. What can we compare such a grade to? Instead, we should be asking what we…

Is this even basic science? It sounds more like an engineering problem, albeit a very hard one. I am not a physicist, but I would consider this more like the Manhattan project -- the science being done is not of the 'deeper under standing of nature' type, but rather 'how do you make a controllable explosion' type. Given that, the way to evaluate the project is not on grants received, articles published or citations i…

Because the only progress can be made on paper(??)

I ask you, how do you know what are they doing at NIF is different, from the for theory important work at LHC?

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#53

Post by pfraze »

Oculus wrote: post #22

> led NIF's critics to label the facility an enormous waste of taxpayer dollars > government shifted NIF away from its fusion goals to focus on its other mission: simulating the conditions inside nuclear weapons I think right there lies the problem with our world. People take up more issue with a multi-billion dollar research facility for science than one for military applications. If we spent a small fraction of the…

Just want to toss in, I think military applications are much easier for the layman to conceptualize. You hear science research and your gut doesn't send any strong signals.

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#54

Post by throwaway_yy2Di »

Here's the paper.

http://www.nature.com/nature/journal/vaop/ncurrent/full/natu...

They would like to charge you $32 to look at it, nature-ally.

The fusion yield is (?) 14 kilojoules (inferring this from physicist Mark Herrman's "5 million billion fusions" [WaPo], at 18 MeV per fusion), which is a moderate improvement over the 8 kilojoule achivement from last fall:

https://news.ycombinator.com/item?id=6459289

[WaPo] http://www.washingtonpost.com/national/health-science/fusion...

The "1%" energy efficiency figure [a] is misleading: 14 kJ is about 1% of 1.5 MJ of ultraviolet light hitting the fuel capsule. But creating that UV pulse consumed 3 MJ of infrared light, which in turn took 400 MJ from the flash bulbs driving the IR laser. So the system efficiency is more like 0.003% (and throwing in hypothetical turbines to generate electricity, 0.001%).

https://en.wikipedia.org/wiki/National_Ignition_Facility#NIF...

[a] I'm referring to this: "while more energy came from fusion than went into the hydrogen fuel, only about 1 percent of the laser's energy ever reached the fuel."

(update: from yosyp's link, the fusion figures were 14.4 kJ, and 17.3 kJ, on two different runs:

https://news.ycombinator.com/item?id=7227950

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#55

Post by adventured »

valarauca1 wrote: post #34
Oculus wrote: post #22

> led NIF's critics to label the facility an enormous waste of taxpayer dollars > government shifted NIF away from its fusion goals to focus on its other mission: simulating the conditions inside nuclear weapons I think right there lies the problem with our world. People take up more issue with a multi-billion dollar research facility for science than one for military applications. If we spent a small fraction of the…

The cost of the B-2 Bomber program has cost as much as ~5 Large Hadron Colliders. B-2 bomber program cost 44.75 billion[1] LHC cost ~7.5 Billion Euro ~9billion USD.[2] [1] http://www.fas.org/man/gao/nsiad97181.htm [2] https://en.wikipedia.org/wiki/Large_Hadron_Collider#Cost

I'd like to have a few more satellites that have the impact of a hubble. That cost ~$4b inflation adjusted.

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#56

Post by jackmaney »

It all fits into my evil plan! You see, I plan to use this "laser" to turn the moon into a weapon. With this "death star", all the governments of the world will be powerless against me! If they try to stop me, I'll use the "death star" to create "nuclear fusion"! [holds right pinky to the corner of his mouth]

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#57

Post by Kroem3r »

lisper wrote: post #32
Kroem3r wrote: post #18

This is newsworthy despite "They didn't get more fusion power out than they put in with the laser"? After decades of work they are orders of magnitude away from break-even. Makes me wonder if the goal is actually break-even and/or power generation. Not really; but it's a revealing question. I'm no great fan of the budgets these huge projects pull down; I think the bang-for-the-buck is greater elsewhere. But modelling…

> This is newsworthy despite "They didn't get more fusion power out than they put in with the laser"? It's not newsworthy, but most reporters are not educated enough to tell the difference between a real breakthrough and a bogus press release.

I think it is newsworthy, but not for the technical details. It's newsworthy because it's such a huge budget, because it's been neutered, because fusion energy research is pathetically funded, and because NIF is like a mean old dog lying in front of the fireplace, farting from time to time - it creams the resources and makes alternatives unappealing.

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#59

Post by chc »

twelvechairs wrote: post #49
icegreentea wrote: post #37

Earlier quoted context omitted.

Do not want to argue with the main thrust of your argument (because I agree with it), but at least part of the reason why people had an issue with the NIF as energy research, but less so as a nuclear test simulator is because the NIF as a device is pretty clearly designed to simulate nuclear detonations. If the problem is "you're wasting taxpayer money", the issue isn't the dollar amount spent, its the return on the…

there's two ways you can take 'return on investment' - the wholistic qualitative way (if x has a tiny chance of improving the whole world then its worth it) or the narrow quantitative way (once we research it, we'l probably have to give x away basically for free and its is likely not to work out anyway and will take years so its practically valueless to our organisation on this years financial model). unfortunately t…

"Return on investment" generally means what you get back for what you put in. Both quality and quantity matter and I think this is often recognized, but if you're getting essentially nothing, it doesn't matter what quality of nothing you get.

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#60

Post by fennecfoxen »

bad_alloc wrote: post #17
ck2 wrote: post #2

Oh please. That whole "fusion" thing from that facility is a trick to get taxpayers to fund more nuclear weapon research. We should have finished this instead, what a waste: http://en.wikipedia.org/wiki/Superconducting_Super_Collider Take a guess why congress only funded the one useful for weapons.

All research into nuclear energy can be used for nuclear weapons. A nuclear reactor is just a well-cooled bomb that isn't supposed to explode violently (so to speak).

Cool! If we ever have WWIII, I'm going to drop a well-cooled H-bomb that uses laser-based confinement mechanism to not explode violently on my enemies. In fact, I await their preemptive surrender even now.
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