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China’s ‘Artificial Sun’ achieves fusion breakthrough

en.people.cn

221–230 of 235 posts

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#221
post #16

Earlier quoted context omitted.

A default position of skepticism works in both cases.

Sure, we have to be careful about these things. Replication is key, which is where the Utah results fell down quickly. Not sure why I'm getting down votes on parent, but there it is.

People downvote the smallest things. I've found it's not as much of an obstacle to continuing the thread as you might think; certainly compared to, say, any moderately popular subreddit.

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#222
post #164

Earlier quoted context omitted.

Sounds like a better track record than Theranos to me.

You are demonstrating awareness of the point being made: if scientific fraud was as rampant here as it is in China, Theranos wouldn't even be remarkable and still unknown. But it is in fact rare enough to cause scandal. If you want to keep that attitude and make non-contributory quips, go back to Reddit. It is not appreciated here.

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Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#223
post #208

Earlier quoted context omitted.

The bulk of the reactor heat needs to stay in the reactor though, doesn't it? as that is essential in keeping the reaction going? How does that affect the economics?

Actually no, the heat needs to escape to keep the temperature under control. The temperature is what has to be kept in the proper range for Fusion to occur at the planned rate. I don't know as much about control of fusion reactions as I'd like, but I think the reaction rate is highly temperature-dependant, so we'll want to keep the temperature in a tight range. Too low a reaction rate, and the plasma cools down too m…

I don't think the plasma being too hot is a problem in a tokamak. The average ion energy is not enough for fusion; we rely on the high-energy tail end of the Maxwellian distribution. Any potential source of heat loss from the ions is a liability, including the natural predilection for ions to transfer their energy to electrons, not to mention radiative losses. Keeping the plasma hot enough is really the essential problem.

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#224

Earlier quoted context omitted.

More importantly, with fusion, energy could become significantly cheaper allowing us to do things which weren't economically viable. Make everything out of environmentally friendly, lighter and long lasting aluminium rather than steel + concrete. Have street lighting that is as bright as sunlight over entire cities, allowing us to no longer be dependant on time of day. Growing food crops indoors with artificial light…

I made me curious about something. Will the heat from all that electricity generation affect the environment in significant ways? At which energy usage scale humanity will be restricted by the planet environment capacity to deal with the generated heat?

If you have enough cheap energy, you could refrigerate earth and send excess heat to space.

I think we're a long way from that yet though.

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#225

I would love to see a huge effort towards fusion, on the same (or even greater) scale as the Manhattan project or the Apollo program. I had been disappointed in the way that fusion always seemed to be 30 years away no matter how many years went past, but I just assumed that that was because the science was hard and just the way it had to be. https://i.imgur.com/sjH5r.jpg https://www.21stcenturysciencetech.com/Article…

Wait for the AI revolution to happen and Singurality to come true. Then AI would devise a fusion reactor for itself and humanity.

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#227
post #120

Earlier quoted context omitted.

> The only up side is that the decay products have a shorter half life. So the waste will only be a problem for a century or so, instead of for millennia. This sounds like a tremendous underestimation of the problem - handling waste. We have people who live 'for a century or so' but we don't even have languages (now!) that have lasted a millenia.

> we don't even have languages (now!) that have lasted a millenia. Wut?

You might make the case that MSA and Classical Arabic is an exception, but MSA is not spoken natively AFAIK. Other than that, I cannot think of any examples where a language spoken by someone a thousand years ago would be intelligible now. Languages change in sound, structure and vocabulary over time naturally. That's how we got the Romance languages from Latin (which is no longer spoken). However, language standardization artificially slows down change, so current languages might last a lot longer. English hasn't changed that much since Shakespeare and the KJV. Maybe interesting to you: https://en.m.wikipedia.org/w/index.php?title=Conservative_(l...

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#228

Earlier quoted context omitted.

Much of the nasty stuff comes from the fact that current (light water) reactors were actually meant to produce military plutonium. Bombs first. Energy was a by-product, and a very nice way to sell nuke-making to the civilians. There is another way of doing fission, that was demonstrated (working prototype and all) in the 60's: molten salt. You basically dissolve the fissile matter in molten salt, provide initial heat…

I don't know who in the thorium boosters' club started the "light water reactors were meant for weapons plutonium" meme but it's nonsense. To quote "Technologies Underlying Weapons of Mass Destruction", Reactor-grade plutonium recovered from civilian reactors differs from weapon-grade plutonium in the relative proportions of various plutonium isotopes. Reactor-grade plutonium has a higher rate of spontaneous fission…

>I don't know who in the thorium boosters' club started the "light water reactors were meant for weapons plutonium" meme but it's nonsense.

Maybe the misunderstanding started from the fact that the first British power-generation reactors were intended to produce weapons-grade plutonium. Those reactors were quite different from light-water reactors: graphite-moderated, gas-cooled, and using unenriched fuel.

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#229

Earlier quoted context omitted.

> we don't even have languages (now!) that have lasted a millenia. Wut?

You might make the case that MSA and Classical Arabic is an exception, but MSA is not spoken natively AFAIK. Other than that, I cannot think of any examples where a language spoken by someone a thousand years ago would be intelligible now. Languages change in sound, structure and vocabulary over time naturally. That's how we got the Romance languages from Latin (which is no longer spoken). However, language standardi…

What about Hebrew?

Re: China’s ‘Artificial Sun’ achieves fusion breakthrough

#230
post #229

Earlier quoted context omitted.

You might make the case that MSA and Classical Arabic is an exception, but MSA is not spoken natively AFAIK. Other than that, I cannot think of any examples where a language spoken by someone a thousand years ago would be intelligible now. Languages change in sound, structure and vocabulary over time naturally. That's how we got the Romance languages from Latin (which is no longer spoken). However, language standardi…

What about Hebrew?

Yes, for written form you could make that argument, though there are some differences between the two. Also, it didn't really "last" in the normal sense, since it was revived in modern times.

Also, Tibetan maintains the same spellings from 1200 years ago, but that really just means that it's very, very difficult to spell, since the pronunciation no longer matches spelling well.

These make interesting exceptions to the general rule, so I think the original point is still very valid. I'm curious about old vs. modern Syrian, if anyone knows about that.

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