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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

#171

Post by oscargrouch »

rockyleal wrote: post #148
oscargrouch wrote: post #111

Earlier quoted context omitted.

By terrorists you mean those illusionary guys that the politicians use as the boogie man, to beat down the rationality of ordinary people by provoking fear, so they are legally allowed to do virtually anything without nobody to stop them?

No I think he means the terrorists that want to kill you because you are free to pay for everything.

Much more likely we gonna be killed by diabetes, or falling from the stairs.. the propaganda is unproportional to the size of the threat.. meanwhile, other types of "predators" may scape from our sight.. not minimizing the problem.. just saying that there are bigger ones that deserve more attention .. and overreacting wont help, i think, anybody.. so, back to the original topic..

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#172

Post by CamperBob2 »

leobelle wrote: post #107
gizmo686 wrote: post #96

Earlier quoted context omitted.

This isn't protesting the law with civil disobedience, it is breaking the law because the direct expected value of breaking the law (people having access to this specific paper) is greater then the expected cost of breaking the law (~0).

Are you a psychopath? In what world does personal expected value versus expected cost of breaking the law ever become a good way to make moral decisions? If you have the chance to get a promotion by killing your boss but have near zero chance of being caught due to some circumstance, would you kill your boss? What the fuck.

In what world does personal expected value versus expected cost of breaking the law ever become a good way to make moral decisions?

In this one, where my taxes paid for the goddamned research.

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#173

Post by dredmorbius »

YokoZar wrote: post #166
dredmorbius wrote: post #160

Earlier quoted context omitted.

However that growth is precisely what the present human civilization and economic system are predicated on. That growth will stop sometime and a considerable amount of present pain seems to be that global growth is slowing markedly (and has been since the 1970s). Globally, economic activity and energy consumption are still tightly correlated: http://www.reddit.com/r/dredmorbius/comments/1vlksg/economic...

Yes, and when you're a child your caloric intake and your yearly increase in height are very tightly correlated too. Lots of society is built around this growth, such as the expectation of having to buy bigger clothes every year. But even a child can understand that one day they will stop growing and eat approximately the same amount of food for the rest of their life. It would be "strange" to argue that, as a teenag…

Humans run through a well-understood lifetime cycle of growth, maturity, and decline. Contemporary orthodoxy neoclassical economics doesn't generally recognize this, though it's beginning to. See Tim Worstall at the Telegraph UK: "Infinite growth on a finite planet? Easy-peasy!" http://blogs.telegraph.co.uk/finance/timworstall/100017248/i...

On the other side, Robert Gordon's "End of Growth" paper: http://www.voxeu.org/article/us-economic-growth-over

Your assertion that a person earning 100k doesn't have twice the energy (or environmental) footprint of someone earning 50k really needs some sort of factual support.

And your hypothetical future with 100s of times today's economic productivity flies in the face of the law of diminishing returns which you've invoked yourself.

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#174

Post by jonmrodriguez »

gwern wrote: post #143
jonmrodriguez wrote: post #36

Earlier quoted context omitted.

Totally agree. Just so you know, the purpose of the NIF was for military testing right from the beginning. The reason it initially got funded (shortly after the end of the cold war) was to help with stockpile stewardship (making sure our aging weapons still work via simulation, without having to do actual weapon tests). http://en.wikipedia.org/wiki/National_Ignition_Facility#NIF_... http://en.wikipedia.org/wiki/Stock…

One of my favorite novels, Carter Scholz's _Radiance_, spends much of its length all on NIF and this controversy, actually: http://www.gwern.net/docs/2002-radiance

Wow, sounds like an exciting premise!

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#175

Post by VladRussian2 »

throwaway_yy2Di wrote: post #68
throwaway_yy2Di wrote: post #54

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]…

Quick summary of the numbers from wikipedia: 422 MJ capacitors ←────────────┐ ↓ │ (?) xenon flash lamps │ ↓ │ 3 MJ IR laser pulse │ ↓ │ 1.5 MJ UV pulse │ ↓ │ 150 kJ X-ray pulse │ ↓ │ * 14-17 kJ Fusion yield (this story) │ ↓ │ 7-9 kJ Potential electricity →────────┘ system breakeven https://en.wikipedia.org/wiki/National_Ignition_Facility#NIF...

wrt. 422MJ->3MJ, xenon flash lamp pumping

As it was already mentioned in the threads like this before, the NIF was built using the technology that was available in those years of the past when NIF was planned and started. Flash lamp pumped lasers are bigger, more expensive and much less efficient, i.e. mere few percents efficiency at best vs. tens of percent efficiency of modern laser diode pumped IR lasers. (Even with such improvement though, i still think laser driven fusion is inferior to many other forms of inertial confinement and much less probable to result in system-level break-even. My personal favorite, Sandia Z-machine is on the scale of 15% efficiency of generating X-ray pulse, and schemes like deep plasma focus or polywell by-pass the energy to radiation conversion stage all together and thus avoid related losses.)

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#176

Post by arethuza »

vinceguidry wrote: post #146
arethuza wrote: post #119

Earlier quoted context omitted.

I guess availability of fuel is one big advantage, along with the cleanup of a fusion plant hopefully being a lot easier and cheaper than a fission reactor: http://en.wikipedia.org/wiki/Fusion_power#Waste_management A lot safer too!

Isn't the primary cost of fission complying with safety regs? In that case, a safer design would directly translate to lower costs.

According to Wikipedia the cost of electricity from modern nuclear stations is roughly comparable with sources like coal - which surprised me:

http://en.wikipedia.org/wiki/Cost_of_electricity_by_source

What I don't know is how much of the cost of nuclear power is the much higher level of safety precautions they need.

I haven't seen any projected costs for DEMO which might well be the first fusion power plant (DEMO is the proposed successor to ITER):

http://en.wikipedia.org/wiki/DEMO

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#177

Post by anon4 »

yosyp wrote: post #77
throwaway_yy2Di wrote: post #54

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]…

cheers https://dl.dropboxusercontent.com/u/26434203/nature13008.pdf

Muahahaha Ha! I'm not American. I'll read it TWICE and cost you TWICE the taxpayer dollars, then I'll share it with all my friends and soon all the dollars in America will be GONE. Better call the president and tell him to start enacting measures, cause there are no breaks on THIS terrorist train!

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#178

Post by arethuza »

amcnett wrote: post #113
dmix wrote: post #61

Earlier quoted context omitted.

Or even better failed military projects, such as the $25+ billion spent on a spy satellite project before it was killed in 2002. https://en.wikipedia.org/wiki/National_Reconnaissance_Office...

The F-35 is not exactly a resounding success: http://www.bloomberg.com/news/2013-02-22/flawed-f-35-fighter...

It must be a resounding success - the UK is about to commit to buying some - like we committed to buying Skybolt and the F-111 (cancelling the awesome home grown TSR 2 in the process):

http://en.wikipedia.org/wiki/BAC_TSR-2

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#179

Post by collyw »

yen223 wrote: post #169
tptacek wrote: post #131

Earlier quoted context omitted.

Or we could talk about nuclear fusion.

Why talk about what might be the biggest scientific breakthrough of the year, when we can regurgitate snarky comments about Elsevier again?

Well if Elsever would make it easier to access, we wouldn't have to. $32 to read about what might be the biggest breakthrough of the year?

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#180

Post by tripzilch »

leobelle wrote: post #107
gizmo686 wrote: post #96

Earlier quoted context omitted.

This isn't protesting the law with civil disobedience, it is breaking the law because the direct expected value of breaking the law (people having access to this specific paper) is greater then the expected cost of breaking the law (~0).

Are you a psychopath? In what world does personal expected value versus expected cost of breaking the law ever become a good way to make moral decisions? If you have the chance to get a promotion by killing your boss but have near zero chance of being caught due to some circumstance, would you kill your boss? What the fuck.

That's just silly. If you kill your boss, who's going to promote you, and who is going to pay out the higher salary? No, the rational thing to do is to wear his skin to impersonate him and sell all the company's assets. Then eat him.
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