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Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

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Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#111

Post by jakeinspace »

Cthulhu_ wrote: post #69
albertopv wrote: post #57

Earlier quoted context omitted.

I'm very skeptical about those great announcements, even more when there's an announcement of the announcement. 300MJ in, 3MJ out, I wouldn't call it a breakthrough, maybe a milestone, nothing more.

And yet, they need to keep making announcements, else their funding will be cut. They knew all along that fusion energy would take decades to develop, and every year they need billions in funding to keep pushing for advancements. They can't just go radio silent until they're like "we've done it", they need to regularly publish papers and make big media announcements etc. Come to think of it, the LHC has been silent f…

Their funding isn’t getting cut. US spending on updating the nuclear stockpile is going up substantially.

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#112

Post by toomanyrichies »

noobermin wrote: post #90
sigmoid10 wrote: post #86

Earlier quoted context omitted.

You greatly underestimate the order of magnitude difference of produced energy in these two examples. You can't contain a bomb's hydrogen fusion reaction in a chamber for the simple reason that you need a nuclear fission warhead just to ignite it. So if you want to produce useful, controlled energy outside of killing things, the lasers are your only shot for inertial confinement fusion. Yes they still get damaged, bu…

This is the real key. A LOT of people (and digging through their comment history, many of them) are MCF people who somehow poo-poo this result but then go on to extol how MCF schemes or companies are still a safer bet...even when none of them have even achieved any level of Q, heck they didn't even beat NIF's old result. If this result is "useless" and "shouldn't be news," then the whole field of MCF and all the star…

For those who were wondering what "MCF" is (like I was), the above author is likely referring to "magnetic confinement fusion"[1].

Contrast MCF with "inertial confinement fusion"[2] (ICF), a different (and apparently competing) approach taken by the National Ignition Facility in this latest announcement.

1. https://en.wikipedia.org/wiki/Magnetic_confinement_fusion

2. https://en.wikipedia.org/wiki/Inertial_confinement_fusion

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#113

Post by raverbashing »

randallsquared wrote: post #103
sigmoid10 wrote: post #86

Earlier quoted context omitted.

You greatly underestimate the order of magnitude difference of produced energy in these two examples. You can't contain a bomb's hydrogen fusion reaction in a chamber for the simple reason that you need a nuclear fission warhead just to ignite it. So if you want to produce useful, controlled energy outside of killing things, the lasers are your only shot for inertial confinement fusion. Yes they still get damaged, bu…

> You can't contain a bomb's hydrogen fusion reaction in a chamber You certainly can, if you use a large enough chamber. Pacer was exactly this. You just have to accept high proliferation risk.

True.

My crazy idea would be to use the heat and the pressure of these to pump water uphill. It is of course a crazy idea and you'd have to figure out a way to manage the pressure peak

But it would be very interesting

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#114

Post by zmgsabst »

HPsquared wrote: post #97
sigmoid10 wrote: post #86

Earlier quoted context omitted.

You greatly underestimate the order of magnitude difference of produced energy in these two examples. You can't contain a bomb's hydrogen fusion reaction in a chamber for the simple reason that you need a nuclear fission warhead just to ignite it. So if you want to produce useful, controlled energy outside of killing things, the lasers are your only shot for inertial confinement fusion. Yes they still get damaged, bu…

Parent was basically saying it has not been a physics problem for decades, it's already an engineering problem and there is no change there. The physics are known to work and have been demonstrated decades ago in a different engineering context (i.e. weapons).

We can debate the importance, but it’s clear that they’ve made a qualitative leap in their technology the past few years — a “breakthrough”.

https://en.wikipedia.org/wiki/National_Ignition_Facility#/me...

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#115

Post by tonmoy »

This type of nuclear fusion uses tritium, and since we can’t extract it from nature the only way to obtain it is very energy extensive. For this type of fusion to make sense producing tritium+lasers have to require less energy than the output, right?

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#116

Post by mikepurvis »

raverbashing wrote: post #113
randallsquared wrote: post #103

Earlier quoted context omitted.

> You can't contain a bomb's hydrogen fusion reaction in a chamber You certainly can, if you use a large enough chamber. Pacer was exactly this. You just have to accept high proliferation risk.

True. My crazy idea would be to use the heat and the pressure of these to pump water uphill. It is of course a crazy idea and you'd have to figure out a way to manage the pressure peak But it would be very interesting

Pumped hydro has been a concept for a while now for grid storage of power; one of the limitations of it is just the rather unique geography required. Most places with adjacent reservoirs and enough vertical separation between them also have cottages, roads, and other infra that make it hard to be constantly draining and filling.

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#117

Post by zmgsabst »

vesinisa wrote: post #58
bawolff wrote: post #39

Everything i have heard about this makes it sound more like a milestone than a breakthrough. I.e. its great it happened and an important step, but its not shocking that we eventually did it. When i hear breakthrough i think of something more unexpected. I.e. figuring out how to solve a problem we had no idea how to solve.

Exactly.. The article fails to answer the question posed by its very title. What I've gathered, this was a very much expected result and NOT a "breakthrough". And with regards to making fusion a viable source for commercial, large-scale energy production .. this is only tangential at best to that effort. The problem with celebrating "fake victories" (and being scolded for calling them out) is that when there really i…

Their chart seems to indicate that this is a qualitative improvement where the kind of fusion produced substantially changed.

I share your skepticism towards commercial impact — but this is certainly a breakthrough in their technology. Just look at the chart.

https://en.m.wikipedia.org/wiki/National_Ignition_Facility#/...

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#118

Post by galangalalgol »

randallsquared wrote: post #103
sigmoid10 wrote: post #86

Earlier quoted context omitted.

You greatly underestimate the order of magnitude difference of produced energy in these two examples. You can't contain a bomb's hydrogen fusion reaction in a chamber for the simple reason that you need a nuclear fission warhead just to ignite it. So if you want to produce useful, controlled energy outside of killing things, the lasers are your only shot for inertial confinement fusion. Yes they still get damaged, bu…

> You can't contain a bomb's hydrogen fusion reaction in a chamber You certainly can, if you use a large enough chamber. Pacer was exactly this. You just have to accept high proliferation risk.

Thank you for pointing me to Pacer, that was a fascinating read. They were apparently also considering digging a new panama canal with fusion bombs...

In 1972 they decided it wasn't economical based on fuel price compared to yellowcake, but fissile fuel isn't the primary cost of fission power and the engineering costs of pacer would seem to be much lower.

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#119

Post by zmgsabst »

hoseja wrote: post #81
albertopv wrote: post #72

Earlier quoted context omitted.

There is no energy harvesting system yet, next prototype will be include that. I like their "fast" (relatively speaking, of course) prototyping process.

Why not do a major announcement with the working prototype though, is what's ringing the alarm bells for me. Yeah sure they can promise the next prototype will do the magic thing but why not wait for that.

This one already does reliable aneutronic fusion using an unusual method.

Why not announce that?

Re: Nuclear physicist explains why fusion ignition is hailed as a major breakthrough

#120

Post by dotnet00 »

bawolff wrote: post #39

Everything i have heard about this makes it sound more like a milestone than a breakthrough. I.e. its great it happened and an important step, but its not shocking that we eventually did it. When i hear breakthrough i think of something more unexpected. I.e. figuring out how to solve a problem we had no idea how to solve.

I feel like HN is being especially pedantic and jaded about this specifically and I don't really get why.

Scientifically this is absolutely a breakthrough, just like the detection of the Higgs boson was despite them already having expected it or just like LIGO's detections of gravitational waves were despite that being entirely what it was built for or just as JWST's detections of galaxies much older than those seen from other telescopes was despite that being part of the entire point of dumping billions into it. Ingenuity's first flight was also hailed as a breakthrough despite that being exactly what it was designed to do.

In every case we had an idea of how to solve a problem and the outcome was generally expected. All that had changed was that the data had been collected of the solution working, just as it has been in this case.

To put it differently, it's a breakthrough because after decades of work, the National Ignition Facility can actually achieve the thing in its name.

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