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Why is nuclear fusion so hard?

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Re: Why is nuclear fusion so hard?

#121

Post by aurizon »

mdpopescu wrote: post #115
aurizon wrote: post #93

Here is a thought experiment( no cats harmed or wetted). Show a cat how the toilet flushes, then try to flush the cat. You have two hands, the cat has 4 paws, with sharp claws as well as teeth. This will give you an idea.... Stars have gravity and mass- we do not, so we must try and compress the plasma, heat it AND stops the paws from grabbing the exterior. In truth magnetic confinement is a poor way to constrain a p…

Controlled fusion has always been 5 to 10 years away, just as we've always been at war with Eurasia.

That is partly true,but we ave advanced to the point where the next generation of machines take 5 years or more to build. They have reached the break even and gone substantially past it, but they have not been ablt to reduce it to the turn-key appliance stage.

Re: Why is nuclear fusion so hard?

#122

Post by bjelkeman-again »

wbl wrote: post #69
DennisP wrote: post #61

Earlier quoted context omitted.

No, it's saying that large-scale fusion using hydrogen fuel requires a star, because hydrogen fusion reactions are very improbable. That reaction only happens when four nuclei collide at once. Fortunately we have other fusion fuels that are much more likely to fuse, including deuterium, which makes up 1/2500 of the hydrogen atoms in the ocean. Most projects target the easiest fuel, deuterium-tritium; while tritium is…

Nope! The p-p chain only has pairwise interactions. The issue is the p+p->d step is very disfavored, thanks to the weak step. D+T is all strong interaction.

Could that be explained with less jargon? I’d like to understand it.

Re: Why is nuclear fusion so hard?

#123

Post by ravar »

bjelkeman-again wrote: post #122
wbl wrote: post #69

Earlier quoted context omitted.

Nope! The p-p chain only has pairwise interactions. The issue is the p+p->d step is very disfavored, thanks to the weak step. D+T is all strong interaction.

Could that be explained with less jargon? I’d like to understand it.

There is a chain of individual steps that need to happen to create the final product of hydrogen fusion, helium. One of the crucial steps is the production of deuterium from two protons. This step is incredibly slow and limits the rest of the chain. However if you skip the slow step and start by fusing deuterium and tritium you can have a much faster and efficient reactor.

Re: Why is nuclear fusion so hard?

#124

Post by afrodc_ »

intralizee wrote: post #36
oblio wrote: post #32

Earlier quoted context omitted.

Why do you need it to be legalized? After all, it's a one way trip, you don't care about being convicted post mortem, do you? :)

Statistically failure rate is high and where the very real outcome of brain damage is possible. Wouldn’t want to be stuck in a state causing more resources spent and unable to attempt the act again. I am seeking it medically for the record and I assume most people are just irrational against letting people die which is why this world is in jeopardy anyway.

Please seek help

Online: https://suicidepreventionlifeline.org

Phone: 1-800-273-8255

Re: Why is nuclear fusion so hard?

#125

Post by fromMars »

acqq wrote: post #103
fromMars wrote: post #85

Earlier quoted context omitted.

I posted further up thread, and I am not an expert, that thorium based nuclear power may be safer with less dangerous waste and potential for weaponization.

https://www.theguardian.com/environment/2011/jun/23/thorium-... "Don't believe the spin on thorium being a greener nuclear option" and https://thebulletin.org/2018/08/thorium-power-has-a-protacti... "Protactinium separations provide a pathway for obtaining highly attractive weapons-grade uranium 233 from thorium fuel cycles. The difficulties of safeguarding commercial spent fuel reprocessing are significant for any t…

What I got from the first article you linked is that Thorium reactors produce less radioactive waste but are unproven technologies.

Re: Why is nuclear fusion so hard?

#126

Post by imhoguy »

oblio wrote: post #32
intralizee wrote: post #27

Earlier quoted context omitted.

Sure, legalize suicide and make it possible to receive in a humane medical setting.

Why do you need it to be legalized? After all, it's a one way trip, you don't care about being convicted post mortem, do you? :)

I care about life insurance payout to my relatives in case I become terminaly sick and want some dignity.

Re: Why is nuclear fusion so hard?

#127

Post by Koshkin »

narag wrote: post #112
simonh wrote: post #96

Earlier quoted context omitted.

I suppose the universe doesn't owe us a cheap, easy, unlimited source of energy. A lot of people seem to think that it's inevitable we will achieve amazing, magical feats of technology given sufficient time and effort that are unthinkable today. Maybe. But it's also just as possible that we already know most of the general parameters of what is possible in the universe, and the peak practical feats of technology that…

Nuclear tech is not even a century old. The idea that we can't do any better in a thousand or a million years seems so improbable to me that I can't take it seriously. There is some kind of extrange pessimism around that mindset: that we will be extinct much sooner, or that the Sun will die and thus Humanity, as if there's no obvious way to escape that apocalypsis.

> do any better in a thousand or a million years

From what I can tell, there is a much bigger chance that we'll do much worse - and much sooner.

Re: Why is nuclear fusion so hard?

#128

Post by DennisP »

ravar wrote: post #123
bjelkeman-again wrote: post #122

Earlier quoted context omitted.

Could that be explained with less jargon? I’d like to understand it.

There is a chain of individual steps that need to happen to create the final product of hydrogen fusion, helium. One of the crucial steps is the production of deuterium from two protons. This step is incredibly slow and limits the rest of the chain. However if you skip the slow step and start by fusing deuterium and tritium you can have a much faster and efficient reactor.

Thanks, that was interesting. Apparently the five-minute video I got my statement from led me astray.

Re: Why is nuclear fusion so hard?

#129

Post by intralizee »

User23 wrote: post #116
intralizee wrote: post #36

Earlier quoted context omitted.

Statistically failure rate is high and where the very real outcome of brain damage is possible. Wouldn’t want to be stuck in a state causing more resources spent and unable to attempt the act again. I am seeking it medically for the record and I assume most people are just irrational against letting people die which is why this world is in jeopardy anyway.

Interestingly and sadly a rather bright young man set his mind to exactly this problem and engineered a solution. https://imgur.com/a/Z5mEB#0bVIYlf

Yah I've seen it before and personally I know someone who had success with a shotgun but I would prefer something guaranteed by society.

Re: Why is nuclear fusion so hard?

#130

Post by intralizee »

afrodc_ wrote: post #124
intralizee wrote: post #36

Earlier quoted context omitted.

Statistically failure rate is high and where the very real outcome of brain damage is possible. Wouldn’t want to be stuck in a state causing more resources spent and unable to attempt the act again. I am seeking it medically for the record and I assume most people are just irrational against letting people die which is why this world is in jeopardy anyway.

Please seek help Online: https://suicidepreventionlifeline.org Phone: 1-800-273-8255

What makes you think I haven't attempted to use all the available resources yet? I'm seeking the next best solution after rationally doing all that could be done.
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