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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

#61

Post by dmix »

Oculus wrote: post #40
valarauca1 wrote: post #34

Earlier quoted context omitted.

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

The B-2 Bomber is child's play compared to the F-35's 1 Trillion USD program [1], but the comparison to the LHC's pricetag really puts things in prespective. 1: http://www.reuters.com/article/2012/03/29/us-lockheed-fighte...

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...

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#62

Post by wcoenen »

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…

> we could probably solve some really fundamental world problems (i.e. energy, climate change) in the near future

I have a feeling that if we had fusion plants providing limitless cheap power, we'd get back on an 8% yearly growth track for energy consumption, like with oil consumption before 1970.

Then within a century or so, we'd be producing an amount of power equivalent to 20% of what the earth receives from the sun. It would give a whole new meaning to "global warming".

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#63

Post by Kroem3r »

vezzy-fnord wrote: post #39
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…

Not necessarily true. A lot of great innovations have originated from military research. War necessitates innovation. Not to say that we should just funnel everything into the military, but one should not underestimate its importance in the technological landscape.

This seems like a myth to me. Radar? Rocket engines? Turing? Stealth bomber technology? Nuclear powered aircraft carriers? ICBMs? Stuff that was happening regardless of a war and stuff that was nearly useless.

Perhaps military first adopters are a net positive; like, the first buyers of a technology who will pay top dollar for working prototypes. But what on the original innovation side can you actually attribute?

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#64

Post by Zancarius »

deletes wrote: post #43
valarauca1 wrote: post #34

Earlier quoted context omitted.

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

Yeah... I see no benefit in those, having a few more colliders instead would be really great. Or just start building the next version already!

> Yeah... I see no benefit in those, having a few more colliders instead would be really great.

That's because you're seeing it through the lens of our time. Remember, the B-2, and many other programs including the F-22, were devised during the trailing end of the Cold War (edit: that's actually a lie; the call for contracts and other such nonsense that would lead to the B-2 started in the 70s, and the F-22 program had existed in some form since the very early 80s). Whatever your conviction about whether or not such things should exist, government (and their militaries) in particular has a great deal of inertia, both in terms of expenditures and policies. So while both programs were in full swing during the collapse of the USSR, that era is primarily what laid the groundwork for such expenses.

Personally, I'm a fan of both. I love the hardware used in high energy physics. And I love military hardware.

If I were about 15 years younger and lived in a wetter climate, I'd go outside and splash in the mud right now. ;)

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#65

Post by aqme28 »

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…

It's definitely still a science. For example, there are still basic fluid-mechanics questions we don't fully understand about how plasmas behave. Also there's this journal: http://www.ans.org/pubs/journals/fst/

Disclaimer: I worked in a fusion lab in undergrad.

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#66

Post by cLeEOGPw »

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]…

As I understand, they are hoping to achieve fusion ignition, where no additional external energy will be required to generate power. So current efficiency calculations are irrelevant in that case.

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#67

Post by DougMerritt »

willvarfar wrote: post #50
DougMerritt wrote: post #31

Earlier quoted context omitted.

Good way of putting it so that people can understand. Feynman was a scientist, not an engineer, so that's a clue that the Manhattan project involved science, not just engineering. The same is true of fusion research. That's why it's "research", not merely "development". In particular, the physics of plasma instabilities has always been quite imperfectly understood, and that has been one of the key problems with contr…

I thought his role on the Manhattan project was keeping the IBM calculators going?

That is far from the only thing he did. He was the wunderkind of the project, and he did all kinds of things.

See for instance Gleick's Feynman biography, "Genius".

http://www.goodreads.com/book/show/98685.Genius

Another good read about the project is this bio: "The Curve of Binding Energy: A Journey into the Awesome and Alarming World of Theodore B. Taylor"

...which is obviously mostly about Taylor (on the Manhattan Project), but has some Feynman anecdotes.

http://www.goodreads.com/book/show/54968.The_Curve_of_Bindin...

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#68

Post by throwaway_yy2Di »

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...

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#69

Post by PhasmaFelis »

JoeAltmaier wrote: post #6
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…

That's not enough. Learning what doesn't work is sort of useful, but only if it ever leads to something that DOES work. There's an infinite supply of dead ends out there. You need a higher bar than 'learned something' if that something is a negative.

I'm not a scientist, but I am a programmer, and I find that learning new things is very often a process of eliminating dead ends through trial and error. That's how you narrow it down to the thing that actually does work.

It sounds like you're saying "don't bother exploring dead ends, either do it right the first time or give up," which is a lot like saying "I just want a penthouse apartment, stop wasting time building a foundation."

Re: Scientists Say Their Giant Laser Has Produced Nuclear Fusion

#70

Post by throwaway_yy2Di »

cLeEOGPw wrote: post #66
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]…

As I understand, they are hoping to achieve fusion ignition, where no additional external energy will be required to generate power. So current efficiency calculations are irrelevant in that case.

Yes, but in the article they also say this isn't possible with their current techniques.

Anyone have a figure that represents how far off they are?

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