831–840 of 1001 posts
What’s the difference between "ignition" and every other “fusion achieved“ news story I’ve seen in the last 40 years? This has the feel of those “water discovered on Mars for the first time ever” headlines.
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> [...], 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.
This is incredible.
Good old Wikipedia has this gem:
> The large power output of the Sun is mainly due to the huge size and density of its core (compared to Earth and objects on Earth), with only a fairly small amount of power being generated per cubic metre. Theoretical models of the Sun's interior indicate a maximum power density, or energy production, of approximately 276.5 watts per cubic metre at the center of the core,[63] which is about the same power density inside a compost pile.
https://en.wikipedia.org/wiki/Sun#Core
Another fun fact: there's a decades old design for a gadget that fits at the top of your desk and does nuclear fusion. You could build one yourself, if you are sufficiently dedicated. Unfortunately, no one has ever worked out how to run one of them as a power plant. Ie how to get more useful energy out than you have to put in.
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Wind and solar have a max theoretical output that is constrained by physical space and competition for its use, in addition to weather patterns, etc. Fusion energy has a theoretical max that’s orders of magnitude higher. Wind+solar is the path to decarbonization and sustaining our current world. Fusion is the path to post scarcity. If/when we get scalable commercial fusion, it’ll be like the transition to oil - socie…
> Fusion is the path to post scarcity. If/when we get scalable commercial fusion, it’ll be like the transition to oil - society will radically change, in ways we can’t predict. Except this is also true for fission. So if fission has failed to transform society, why do you think fusion will?
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How would it help build better weapons? I thought the existing thermonuclear bombs do the job perfectly fine. Sure, the military might want to make them a bit smaller or a bit cheaper, but is it really such a big deal as to warrant a major announcement?
"Nuclear stockpile research" is only making weapons "better" in the sense that they are reliable despite not having been tested in decades. There's probably a component of "unemployed nuclear weapons designers is a bad thing" also. The fusion for power experiments are using the same laser equipment but different targets and sensors.
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How would it help build better weapons? I thought the existing thermonuclear bombs do the job perfectly fine. Sure, the military might want to make them a bit smaller or a bit cheaper, but is it really such a big deal as to warrant a major announcement?
Given the limitations on nuclear research for weapons purposes any information that can be gleaned from these experiments that is 'dual use' is more than welcome with the parties that are currently stymied by various arms control agreements. This is also why you will see a lot of supercomputer capacity near such research, it allows simulation of experiments with high fidelity rather than the experiments themselves. T…
When (in XX years?) almost all US nukes are only simulated on computers and not actually tested, the Russians may start wondering if the US aresnal actually works, no? That would be a horrible outcome, since it means the Russians would be taking somewhat greater risks in their decision-making. Wouldn't far outweigh any opertaional or financial benefits the newer designs offer?
I suppose one could argue that if the loss of confidence in strategic weapons matched the actual loss in reliability, it might be a "no op" (although even this is arguable). But if the Russians think the US simulations suck, while the US is actually building really good simulations, the loss of confidence would be greater than the actual loss in reliability. In the extreme case, the nukes work great, but everyone thinks they are scrap metal.
Of course, the same happens in reverse: if the Russians are upgrading their weapons to untested designs, the US may start underestimating the risk.
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How would it help build better weapons? I thought the existing thermonuclear bombs do the job perfectly fine. Sure, the military might want to make them a bit smaller or a bit cheaper, but is it really such a big deal as to warrant a major announcement?
The USA no longer has the technical capability to manufacture the necessary parts to maintain the current stockpile. The whole strategic arms reduction treaty regime is basically a fig leaf to cover for the fact that we have to cannibalize some legacy weapons to maintain the rest. If nothing changes the USA probably won't have an effective arsenal within a century. Given the likely state of the USA by that time, that…
1. How does this research help address this problem?
2. What are the sources for your opinion?
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> they're working on getting you to click on an ad They're not, and there's zero evidence to back that frequently floated premise up. That's a particularly laughable myth created by those same industry people to feel better about their terrible life choices. If you can't do something meaningful, at least you can pretend to be a genius doing nothing meaningful. It turns out that both things are false, they're not bril…
A lot of wonderful people are doing that, but do those jobs pay anywhere close to the ad companies? Surely there's a lot of bright minds lost to the allure of money.
[1] This is up 1.1% year-over-year, and only up 6.5% p.a. over the last three years - not a pandemic-driven bubble. Source is https://www.redfin.com/county/733/IL/DuPage-County/housing-m...
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How easy is to write $1T, but with that you can basically install enough solar cell to power all of USA energy need.
No you can't because solar isn't a continious source and fusion is. No amount of investment into solar power can make the sun magically shine 24 hours a day.
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H-bombs use the hydrogen to produce more neutrons which boosts the fission process. It still is a fission bomb.
No, you can have a fusion booster, like in the "Sloika" [0] design, but for a Teller-Ulam design, that is a H-bomb, you use a nuclear primer to ignite a fusion reaction and by far the most energy comes from the fusion part. [1] [0] https://www.atomicarchive.com/history/hydrogen-bomb/page-11.... [1] https://nuclearweaponarchive.org/Library/Teller.html
https://en.wikipedia.org/wiki/Thermonuclear_weapon
Only very large bombs, such as the Tsar Bomba (97% from fusion) ever where primarily fusion, and those are not in modern arsenals.
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I'm unaware of a clothes washing machine currently on the market that finishes the job in seconds. I believe that the technology has yet to be introduced.
When it is, how many seconds-long washings will my cheaply-made shirts survive? My guess is nearly one.