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US Department of Energy: Fusion Ignition Achieved

energy.gov

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Re: US Department of Energy: Fusion Ignition Achieved

#981

Post by eru »

trompetenaccoun wrote: post #974
hatsunearu wrote: post #948

Earlier quoted context omitted.

Yeah, this is a morbid analogy but if you got a bunch of people enclosed in a small area, the people in the middle will get so hot they will heatstroke, even if it's freezing outside. See the recent Korean crushing disaster.

Don't give them ideas, harnessing people power would solve all the major problems. Overpopulation, global warming, energy crisis,... Reminds me of that 'Mitchell and Webb - Kill all the poor' sketch.

There's no overpopulation problem, and no energy crisis.

Re: US Department of Energy: Fusion Ignition Achieved

#982

Post by eru »

bratbag wrote: post #877
eru wrote: post #871

Earlier quoted context omitted.

Of course, whether that's a good investment of resources right now is another question. Even if we had no other goal than becoming an intergalactic species as soon as possible, we might still benefit from working on other things first.

You are operating under the rather naive assumption that the people and resources used in fusion research are fungible with the people and resources used in other things. When you have a bunch of people who know how to build nuclear bombs sitting around with nothing to do, you damn well keep them busy before another country finds them a job.

For further discussion, we'd need to be careful whose perspective we are taking and what timescales we are talking about.

You seem to be taking the perspective of individual countries? And not eg humanity.

And timescales of perhaps decades?

On longer timescales: people don't get born knowing how to build nuclear bombs. They are trained up.

Re: US Department of Energy: Fusion Ignition Achieved

#983

Post by eru »

throw827474737 wrote: post #873
eru wrote: post #793

Earlier quoted context omitted.

> [...], or the ginormous fusion of the sun. The sun actually has very little fusion per cubic metre or per kg. Per volume the core of the sun produces only a quarter of the heat of the human body (and per kg it's even less, owing to high density). That's why our fusion reactors can't just mimic stars, they have to far surpass them to be useful to us.

That, but also mimicing the pressure of the sun here is just not possible (yet? :D), why we need to play with higher temperaturs with different problematic consequences.

Well, have a look at https://qr.ae/prpVIL which says:

> The highest instantaneous pressures we can obtain here on Earth are in the Fusion reactor at the National Ignition Facility and in Thermonuclear weapon detonations. These achieve pressures of 5 x 10^12 and 6.5 x 10^15 Pascal respectively. For comparison, the pressure inside our Sun’s core is 2.5 x 10^16 Pascal.

Re: US Department of Energy: Fusion Ignition Achieved

#984

Post by eru »

samvher wrote: post #962
eru wrote: post #793

Earlier quoted context omitted.

> [...], or the ginormous fusion of the sun. The sun actually has very little fusion per cubic metre or per kg. Per volume the core of the sun produces only a quarter of the heat of the human body (and per kg it's even less, owing to high density). That's why our fusion reactors can't just mimic stars, they have to far surpass them to be useful to us.

Can you say more about the ways in which fusion reactors need to surpass stars, and why people believe it's feasible that we can sufficiently get to that point? (Also - thanks for sharing one of the most interesting comments I've read on the internet in quite a while.)

See eg https://www.youtube.com/watch?v=ChTJHEdf6yM

Re: US Department of Energy: Fusion Ignition Achieved

#985

Post by trompetenaccoun »

eru wrote: post #981
trompetenaccoun wrote: post #974

Earlier quoted context omitted.

Don't give them ideas, harnessing people power would solve all the major problems. Overpopulation, global warming, energy crisis,... Reminds me of that 'Mitchell and Webb - Kill all the poor' sketch.

There's no overpopulation problem, and no energy crisis.

https://en.wikipedia.org/wiki/2021%E2%80%932022_global_energ...

Re: US Department of Energy: Fusion Ignition Achieved

#986

Post by azinman2 »

rrrrrrrrrrrr2 wrote: post #971
azinman2 wrote: post #956

Earlier quoted context omitted.

Fukushima most recently

And somehow harnessing the power of the literal sun will have a better safety rate? It's all speculation at this point because fusion doesn't exist yet... but it does seem like a huge undertaking to get superior safety over fission.

It’s not speculation because so much is known about the physics and elements involved. With fusion you want lighter particles which tend to be less radioactive, rather than heavy uranium etc particles for fission.

See https://www.iaea.org/bulletin/safety-in-fusion for more details

Re: US Department of Energy: Fusion Ignition Achieved

#987

Post by trhr »

smegger001 wrote: post #419
trhr wrote: post #368

Earlier quoted context omitted.

Quoted post unavailable.

> True in the Civil War. >You think so? Ya'll lost 200,000 men to Southern fever, steel, and shot. Next time it'll be 20 million. Know your limits, yankee, and stay north of Dallas. The south started with a treasonous surprise attack and had most of the the infantry that wasn't stationed in isolated western frontier territory or along the us-canada border, the countries war college at westpoint and many of the countr…

> You got set on fire once when you started the fight with sucker punch, and you want to try to pick fight again?

Sure, you burned Georgia slap up, but not a single one of you set foot in Texas. At least ya'll still had some sense.

Re: US Department of Energy: Fusion Ignition Achieved

#988

Post by Mistletoe »

Balgair wrote: post #922
Mistletoe wrote: post #778

Earlier quoted context omitted.

This is such a profound and deep misunderstanding of this news story.

how so?

The yield numbers don’t factor in all the energy needed for lasers etc. It is still massively in the negative. There is also no feasible way to extract energy from fusion done this way.

I love the optimism but it sets you up for failure and disappointment when you start thinking about all the free energy your children will have from this.

Free energy from a very successful fusion experiment called the sun bathes our planet every day. We know fusion works, but the devil is in the details.

Re: US Department of Energy: Fusion Ignition Achieved

#989

Post by hardnose »

Kukumber wrote: post #387
hardnose wrote: post #310

Earlier quoted context omitted.

Isn't that a bit like saying that every innovation depends upon milk? I guess, technically, every innovation does begin with a baby drinking milk, but it seems like a stretch to attribute the innovation to the milk, rather than to the mind of the individual who may or may not have been fueled by milk?

> it seems like a stretch to attribute the innovation to the milk, rather than to the mind of the individual who may or may not have been fueled by milk? What ever it been fueled with, knowledge wasn't created at an individual's birth, it's an accumulation of a collective and shared effort The point i was trying to make in my post is; it always starts from the people, for the people to continue, for the people to ach…

>we'll have to ask ourselves if giving that much power to the individual a safe endeavor

What's the alternative? Every collective effort is a series of individual efforts.

Re: US Department of Energy: Fusion Ignition Achieved

#990

Post by sumitkumar »

trompetenaccoun wrote: post #974
hatsunearu wrote: post #948

Earlier quoted context omitted.

Yeah, this is a morbid analogy but if you got a bunch of people enclosed in a small area, the people in the middle will get so hot they will heatstroke, even if it's freezing outside. See the recent Korean crushing disaster.

Don't give them ideas, harnessing people power would solve all the major problems. Overpopulation, global warming, energy crisis,... Reminds me of that 'Mitchell and Webb - Kill all the poor' sketch.

Well, plant the idea that there is a fusion reaction going on in mitochondria at a very low scale. Throw in terms like "proton gradient", "electron transport chain" and create a science conspiracy.
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