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Google and a nuclear fusion company have developed a new algorithm

theguardian.com

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Re: Google and a nuclear fusion company have developed a new algorithm

#121

Post by njarboe »

siscia wrote: post #34

I do have a naive question. Suppose a big breakthrough comes out of a private company, and such innovation is necessary to use nuclear fusion. The company will be free to do whatever it pleases with the technology or it will somehow "force" to let other use, maybe behind the payment of some royalties.

Many new technologies take twenty years or more to move from research discovery to commercial application. For example high temperature superconductors (HTS) were discovered in 1986. The Holbrook Superconductor Project in 2008 is what is cited as the first major commercial use of HTS. A few other power projects using HTS are being constructed and HTS is starting to see some use in specialty magnets. How much 20 year patents slow down scientific development is highly debated but most companies try hard to have more than one supplier for anything critical to their business. These companies will tend to avoid having anything patented by some other company in their products.

Re: Google and a nuclear fusion company have developed a new algorithm

#122

Post by igravious »

kilotaras wrote: post #112
igravious wrote: post #109

Earlier quoted context omitted.

Okay, this is really showing my ignorance but why 6? You start off with 4 (3 space plus one time (ignoring 11-dimensional space-time)) and add which dimensions exactly? Can the individual interactions between wave/particles be reduced to 2 dimensions? Aren't they going to interact along the whole range of forces they exert: gravitational, weak, electromagnetic, strong?

3 dimensions for position + 3 dimensions for speed

3 dimensions for momentum in other words? Surely it cannot be that simple. That's astounding.

Re: Google and a nuclear fusion company have developed a new algorithm

#123

Post by euyyn »

regularfry wrote: post #104
euyyn wrote: post #38

Earlier quoted context omitted.

It's a well-known technique in the out-of-fashion world of knowledge-based systems: To create an expert system, your experts often won't be able to articulate their utility function, so you extract it by presenting them A/B choices.

Doing an old thing on a new problem counts as novel.

Sure. Just pointing out that this isn't a "new algorithm that only looks obvious because of hindsight". There's an almost endless supply of problems, like this one, that benefit from automating the assessment task of human experts.

Re: Google and a nuclear fusion company have developed a new algorithm

#126

Post by Libbum »

ohitsdom wrote: post #119
Libbum wrote: post #108

Earlier quoted context omitted.

Interesting. Are you able to provide some links to decent resources on this topic?

Links on DOE? https://www.isixsigma.com/tools-templates/design-of-experime...

Perfect! Thanks.

Re: Google and a nuclear fusion company have developed a new algorithm

#127

Post by abefetterman »

marco_salvatori wrote: post #92
abefetterman wrote: post #16

This is actually a really exciting development to me. (Note, what is exciting is the "optometrist algorithm" from the paper [1] not necessarily googles involvement as pitched in the guardian). Typically a day of shots would need to be programmed out in advance, typically scanning over one dimension (out of hundreds) at a time. It would then take at least a week to analyze the results and create an updated research pl…

Though this work may seem exciting, there is an existing, respected body of work available on how to mathematically structure a search over a large parameter space and how to mathematically interpret experimental responses. That body of work is a subset of applied statistics called design of experiments. It helps scientists avoid the common failures that result from doing exactly what was done here, random space expl…

Reading their actual paper further, it seems I read a bit too much into the original article. However, as their paper mentions:

> The parameter space of C-2U has over one thousand dimensions. Quantities of interest are almost certainly not convex functions of this space. Furthermore, machine performance is strongly affected by uncontrolled time-dependent factors such as vacuum impurities and electrode wear.

I'm not aware of DOE procedures that are robust to these types of issues, and would certainly appreciate any literature you have on the subject.

Regardless of theoretical literature, this procedure has enabled a dramatic shift in how these scientists think about their experiment. Furthermore it has enabled them to achieve results much faster than before (if you have been following Tri Alpha, it has been a real slog). Both of these are exciting to me even if they don't break new ground in the design of experiments.

Re: Google and a nuclear fusion company have developed a new algorithm

#128

Post by drjesusphd »

ktta wrote: post #117
paulsutter wrote: post #84

Earlier quoted context omitted.

Because fusion simulations are really hard. This simulation[1] took 15 million hours of CPU time to model a cubic cm of plasma. The results were used to update 5 scalar parameters in a model. [1] http://news.mit.edu/2016/heat-loss-fusion-reactors-0121

Does anyone have an idea about what software they use to simulate this stuff? I'm wondering if they can even make use of the newfound GPU power or are just going ahead with ancient CPU based software because too much work has already been put in.

It's usually highly-parallelized Fortran ran on the world's largest supercomputers, utilizing thousands of CPU cores. There are several codes like the ones in the study above (google "gyrokinetic equation solver"), and somehow more pop up year by year. So it's not a matter of sunk costs.

And yes, GPUs are increasingly being utilized, depending on the algorithm. But, GPUs aren't magic; they don't speed up every kind of problem.

Re: Google and a nuclear fusion company have developed a new algorithm

#129

Post by drjesusphd »

dwaltrip wrote: post #31

There was a talk about the state of nuclear fusion by some MIT folks linked here on HN a few days ago. One of the biggest takeaways was that many fusion efforts are very far away (3 to 6+ orders of magnitude) on the most important metric, Q, which is energy_out / energy_in. Additionally, much press and public discussion completely fail to discuss this and other core factors that actually matter for making fusion viab…

> One of the biggest takeaways was that many fusion efforts are very far away (3 to 6+ orders of magnitude) on the most important metric, Q, which is energy_out / energy_in.

Keep in mind tokamaks have reached Q=0.7.

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