more like the type most understood to not work.

Simply false. The Q factor is eminently predictable with scale. It is by far the most predictable form of high-Q factor fusion (outside of gravitational, and we're not going there any time soon ;) )

as Robert Bussard said in his famous Google TechTalk in Nov 2006

What, you mean BEFORE we got commercial-scale HTS magnets that scale down the size requirements by an order of magnitude?

Also, pointing to things like ITER to say that cost-effective fusion is impossible is like pointing to the ISS and saying SpaceX is impossible.

And also pointing to a single person's two decades-old view as if it represents a whole field, today (FYI, it doesn't, at all) is pretty damned funny.

Candiakenvirchusevania?

All these commenters who think they're so smart coming out with the same "Fusion power is 20 years away and always will be, har har har!"-quip who don't know a damned thing about the field and its progression is so tiring. One error with neutron measurements at ZETA before we even knew what we were doing, and the entire field was turned into a permanent joke, even as Q factors continued to climb almost monotonically. The press had their story and now we're cursed with an endless stream of these people.

Yeah, so, this is not true.

First off, turning it "to powder" is hyperbole; metals just become increasingly brittle.

Secondly, claiming that there's "no solution" is not just wrong (there are many), the particular solutions used by Commonwealth are literally discussed in the papers that this Slashdot article is about. Specifically, they use a molten FLiBe breeder blanket to absorb the fast neurons, which also breeds tritium. Since it's molten, there are no "structural" issues with it at all. The inner core (mainly tungsten) does need periodic replacements (every 1-2 years), but the reactor is designed to be easy to open up for swap-outs. It is treated as an expendable consumable, and is melted down and recast/rebuilt for the next replacement. In terms of complexity, cost, and downtime, it's probably roughly on par with fission reactor maintenance periods, perhaps superior.

Third, there are many types of magnetic confinement fusion, not just magnetized target fusion. These are less mature than tokamaks, and generally considered more longshots. Even ignoring that the fusion itself is more challenging, they trade something relatively simple - materials science and swapping - for something much harder (immense mechanical and fluid dynamics challenges)

Fourth, if you really hate neutrons, there are also aneutronic fusion designs. Again, though, less mature.

Assuming sparc (no power) costs $1 billion, then guessing that arc costs $5 billion and makes 400MW. You could install about 2GW of sea based wind for the same. With such a huge power surplus over fusion you could probably melt rocks to store power for the still days

1) ~$5B is about right for the first ARC plant, but that's to be expected, because first-of-a-kind plants are always much more expensive. Nth-of-a-kind for ARC is expected to be about $2B.

2) Wind is variable load, not baseload, not load following and certainly not peaking. Its power is worth much less.

3) If you want your wind farm to be able to get through a mere 5 day dunkelflaute and guarantee a steady 400MW output, then, with a 40% round trip efficiency, you have to store 120GWh of thermal energy. Even if your storage is a mere $25/kWh, which is extremely optimistic, that's $3B. And since your wind farm is throwing a lot of its energy away to the losses inherent with thermal storage, you're looking at $5B for the wind farm. And then there's $500M for the power block on top of that. You're looking at a $8,5B project.

(Of course, thankfully, that's not actually how we build out high-renewables grids)

HIGH temperature, not ROOM temperature.

*Facepalm*

God, Slashdot comments sections are so embarrassing these days.

For YHVH's sake, first off "suggest" is not Commonwealth's wording, they wrote five bloody peer-reviewed papers. You're criticizing them based on a word that a Slashdot author chose, likely without even thinking about their wording.

Secondly, there's nothing mystical about tokamak fusion, it's the most well understood type of fusion out there. The scaling factors are well understood. What the "entities" whose "corpses" litter the field didn't have was high-temperature superconducting magnets, as commercial-scale availability of HTS tapes only emerged in relatively recent times. These let you double the field strength. Under tokamak scaling factors, doubling the field strength lets you get the same Q factor at around 1/10th the volume.

There's many other interesting aspects of note, but at a fundamental level, that's all you need to know.

So your idea is that Russia takes Estonia, and then just decides, "Meh, I'm good, that's enough"?

You understand that Estonia is part of Europe, right?

You understand that Estonia is part of the EU, right?

You understand that Estonia is part of the NATO, right?

Also, FWIW, the Russian population of Poland is the size of a large town or a very small city

Russia is more than happy to use "pro-Russian slavs" even if not ethnic Russians. And FYI, 20% of Estonia's population is ethnic Russians.

There actually are ways to poll people in repressive regimes. A classic one goes like this: instead of saying "Do you support President Putin?", you give them a list of a bunch of world leaders - say, Putin, Trump, Modi, Erdogan, and Macron - and ask, "How many of these leaders do you support?" And then you give the next person a different set of leaders - say, Putin, Xi, Starmer, Khamenei, and Merz - and again ask, "How many of these leaders do you support?" You can then statistically disentangle the level of support for Putin, without any individual having to ever say whether they support Putin or not.

Given what Ukraine is managing to get past Russian air defences, do you think Putin is going to nuke Europe and risk French nukes hitting Moscow and Petrograd?

That's not how this works; Russia comes at more powerful opponents sideways, with incrementalism, division, and hybrid warfare. They try to get pro-Russian candidates elected so that they can veto collective action. They have "accidents", such as missiles flying into your airspace, to probe how you'll react, and if the reaction is insufficient, probing ops can go further, or become normalized so that you get used to it and then don't freak out when they go a bit further the next time. They famously support "pro-Russian rebels" (quotation marks definitely demanded) in countries to try to break off chunks, and encourage secession movements. Russia prefers to work piecemeal, tearing apart countries by chunks, and only launching large-scale invasions when they think (rightly or wrongly) that they can get away with it.

Do you honestly think that France would fire nukes at Moscow - and thus face nukes raining down on Paris - if quote-unquote "Russian Separatists" with suspiciously good arms and military training took a chunk of one of the Baltics or Poland? Of course they won't, and Russia knows that. And then, "Oh, we're just sending aid to the oppressed people in the separatist regions!" "Oh, the separatist regions have requested help from us, we're sending advisors!" "Oh no, the separatist regions were "attacked" by their oppressive government, we must launch a counterattack in response!"

This is hybrid warfare. Nobody fires nukes in response to hybrid warfare. Meanwhile, Russia gets incrementally more powerful with each region it captures. A couple decades ago Chechens were bloodying the Russian army. Now they're dying on behalf of the Russian army in Ukraine. Everywhere they take represents human, industrial, and mineral resources. People are constantly propagandized to and kept in a state of poverty from which only service to the Russian state can rescue them.

Yeah, let's feed the Ukrainians into the Russian maw. Want to guess how the Ukrainians feel about that?

Why would you have to "guess" when there's polling? Ukrainians are far less interested in conceding their lands and people to Russia than the west is, in polling.

However, Europe doesn't even have a usable navy to put to sea.

Huh?

The US navy some things it's very good at: nuclear powered carriers, nuclear powered submarines, large surface combatants, and support ships. It sucks at smaller ships (frigates, corvettes) - it's been one project disaster after the next. Europe, by contrast, excels in frigates and corvettes. The US is currently trying to copy the European FREMM as the Constellation class, and it's somehow managing to even screw that up. It's one of the reasons that the US really wanted Europe involved in escort operations in the Persian Gulf - you don't escort a tanker with an aircraft carrier.

With submarines, the US doesn't bother with non-nuclear submarines. That was more defensible in the past, and there's still long distance power projection advantages, but there have been major leaps in AIP in recent decades. Non-nuclear submarines are now far more capable than they used to be. European AIP subs are quieter and much cheaper than US nuclear subs.

Europe also has a strong commercial shipbuilding industry. The US's commercial shipbuilding industry is in a terrible state. The net result of this is that it's often proven difficult for the US to scale up production or adapt to new designs. Europe is more flexabile in its capabilities in this regard.

None of this is to demean the US's unambiguously impressive capabilities in certain naval fields. But to call European navies unusable is... silly?

The economy overall does better if you don't have rent-seeking leachers - if people can use the tools that empower their companies to produce goods and services cheaply and freely.

"Every EV owner I talk to tells me their car is great and how pleasant the ownership experience is; clearly they're all in an organized conspiracy to lie" is.... certainly quite the take you have there.

Doesn't hurt, it's just disappointing that people keep falling for what seem to me such obvious scams. People are so desperate for the "Plucky Inventor Overturns An Industry's Premises" narrative.

Honestly, I somewhat suspect that most of the people involved in this fraud didn't actually know it's a fraud, or at least didn't actually know the full extent of it. You have a struggling electric motorcycle maker with what seems like genuinely decent electric motorbike, who thinks that if they can get a battery that nobody else has for their bikes it'll save their company, and seemingly only slowly starts to realize that it's not what they thought it was. You have a startup cell manufacturer who is approached by companies making the materials to include in their cells. Even at the coating manufacturer, which seems to have been ground zero for the fraud, there were probably plenty of employees in the dark about what was going on, while those who knew what were going on probably thought they were going to "fake it until they make it".