101–110 of 141 posts
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The first fusion-powered blockchain should push HN to cynicism supercriticality.
Fairly confident we’ll get fusion before we use a “blockchain” to buy a loaf of bread.
The amount of cynicism around fusion is stupid. It reminds me a lot of the learned helplessness that surrounded the idea of reusable spacecraft. A little engineering later: https://www.youtube.com/watch?v=sf4qRY3h_eo Fusion is a harder problem than that but we have no physical reason to believe it is not possible and the surrounding technology like compact higher temperature superconductors has advanced significantly…
We have excellent physical reasons to think DT fusion will not be practical. The power density will be terrible, so it would be more expensive than fission at boiling water -- and fission isn't competitive these days.
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It's so cool, though. The power of the sun, in the palm of my hand!
Solar panels harness the power of the sun too. Fun fact: The sun's energy density is only a few watts per ton. A thousand-pound chunk of the sun could barely run a flashlight. Practical fusion requires H/He conversion rates exponentially faster than stars. Yes, i meant to say power density rather than energy. My bad.
It is a tiny sun!
(Well, sorta kinda)
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Cynicism is well justified, given history and the present landscape. Suppose they get this working, and able to produce, what, 300 MW worth of hot neutrons. They have to capture the neutrons and turn them into heat to boil water to drive a turbine to get out 150 MW. Thus, handle the, what, 1000 tons? 10,000 tons? of lithium needed to capture all those neutrons. And, I guess, sieve it for tritium? Maybe chemically sep…
> Cynicism is well justified, given history and the present landscape. The history, measured by the fusion triple product, is exponential progress on par with Moore's law [1], despite abysmal funding [2]. [1] Figure 1, https://www.scipedia.com/public/Sanchez_2014a [2] https://hardware.slashdot.org/story/12/04/11/0435231/mit-fus...
The amount of cynicism around fusion is stupid. It reminds me a lot of the learned helplessness that surrounded the idea of reusable spacecraft. A little engineering later: https://www.youtube.com/watch?v=sf4qRY3h_eo Fusion is a harder problem than that but we have no physical reason to believe it is not possible and the surrounding technology like compact higher temperature superconductors has advanced significantly…
The amount of cynicism around fusion is stupid. It reminds me a lot of the learned helplessness that surrounded the idea of reusable spacecraft. One of the easiest (laziest?) positions one can hold is simply to be dismissive of anything that hasn't happened yet, and which appears to be moderately difficult or harder. Fusion, AGI, etc... Just dismiss those things as ridiculous and you position yourself as wise, inform…
>> Plans for a “gain” experiment (more energy out than in) are advancing at pace. So the headline is very precise: they achieved fusion, but not power production using fusion. And as far as I can tell, achieving fusion is not the hard part.
As far as I can tell, the newsworthy part is that they achieve fusion using their "two-phase" which is supposedly different than conventional tokamaks such as ITER uses. I'm not sure how either of those technologies exactly work, but the article seems to suggest this is a cheaper way to build a fusion reactor. Then again, this is a press piece, so not exactly unbiased.
This is just a press release, but an unusually informative one. For more information on what they have and have not done, see here: https://twitter.com/FLF_Nick/status/1511374600575365122
(Link from apendleton: https://news.ycombinator.com/item?id=30923527)
They have good evidence of deuterium-deuterium fusion. IIRC this is harder to achieve than deuterium-tritium fusion, but as tritium is radioactive with a half-life of ~12 years, it is much harder to acquire and work with. In their concept of a power reactor, they would apparently use the deuterium-tritium reaction, which with the latter being created by bombarding a lithium blanket with the neutrons produced by the reaction, something that is envisaged in most other fusion power concepts.
Wait'll they hear about what those folks at CERN are doing.
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Would Brits scheme , as a verb, in a non-nefarious way? I note we here use schema , which is partly why I interpret a scheme neutrally.
No, I don't think we would. The verb carries an amount of deviousness. I don't know how the word carries so substantially different moral leanings, but that's English. I'm sure there are many other words with evil twins.
There's a book published by some Brits in Oxford that very usefully researches the history of English words. They have found examples of all the meanings discussed here from the mid-to-late 17th and early 18th centuries, FWIW.
The amount of cynicism around fusion is stupid. It reminds me a lot of the learned helplessness that surrounded the idea of reusable spacecraft. A little engineering later: https://www.youtube.com/watch?v=sf4qRY3h_eo Fusion is a harder problem than that but we have no physical reason to believe it is not possible and the surrounding technology like compact higher temperature superconductors has advanced significantly…
(There's that one quote from a startup founder, "we did it because we didn't realize how hard it was", or something like that. From a pg essay maybe?)
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Solar panels harness the power of the sun too. Fun fact: The sun's energy density is only a few watts per ton. A thousand-pound chunk of the sun could barely run a flashlight. Practical fusion requires H/He conversion rates exponentially faster than stars. Yes, i meant to say power density rather than energy. My bad.
Yes, but this I suppose is a bit like a mechanical watch (if many orders of magnitude less practical). You can spend $30,000 on a watch that keeps terrible time in comparison to a $10 quartz watch. But you know there's all these tiny precision machines inside ticking away, and that makes you happy. The only power I can extract from a fusor is the current generated inside a Geiger counter. But in my head, I know there…