Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Skunk Works Reveals Compact Fusion Reactor Details

aviationweek.com

Post reply on HN
Print view View original

211–220 of 375 posts

Re: Skunk Works Reveals Compact Fusion Reactor Details

#211

Post by macinjosh »

protonfish wrote: post #207
jsmthrowaway wrote: post #194

Earlier quoted context omitted.

It's always a safe bet that the top Hacker News comment will always be "won't work, it's too hard." It's like sitting around for a year trying to sell a project at my current employer, with everybody and their lead telling you "that'll never work," then you implement in a weekend and those same people start nitpicking what you've come up with. (What happened to it'll never work? "Well, your CSS isn't great.") Honestl…

And it's always a safe bet the top response to that comment will be somebody criticizing it without any solid facts or reason but with fuzzy "you just need to believe harder!" kind of nonsense.

It is also a safe bet that the response to the original comment's response will be some guy saying how being hopeful about something is complete nonsense.

It's turtles all the way down. Guess we should just give up on Internet commenting. /s

Re: Skunk Works Reveals Compact Fusion Reactor Details

#212

Post by wolf550e »

raverbashing wrote: post #63
etiam wrote: post #9

> U.S. submarines and aircraft carriers run on nuclear power, but they have large fusion reactors on board that have to be replaced on a regular cycle. sigh To the extent this is true I suspect those "large fusion reactors" are tuned not so much for generating electricity and a great deal for annihilating whatever the carrying missile is pointed at. But never mind fuzzy thinking at Reuters right now. This is amazing…

From what I've heard, the reactor actually outlives the ship, no?

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

Re: Skunk Works Reveals Compact Fusion Reactor Details

#213

Post by rayiner »

jsmthrowaway wrote: post #194
nabla9 wrote: post #164

I'm not seeing any top physicists working in this program (McGuire is not one). I would be willing to bet 1000 EUR that their math and modeling does not add up, or they have skipped some details. Problem with fusion research like this is that the closer you get self sustainment or energy generation, the harder it gets and problems pile up. This project looks like many other similar projects that have gone bust. They…

It's always a safe bet that the top Hacker News comment will always be "won't work, it's too hard." It's like sitting around for a year trying to sell a project at my current employer, with everybody and their lead telling you "that'll never work," then you implement in a weekend and those same people start nitpicking what you've come up with. (What happened to it'll never work? "Well, your CSS isn't great.") Honestl…

That's hardly ever true. In my experience, Hacker News is full of people from the software field; folks whose professions are often unconstrained by physics,[1] and who have a generally optimistic "this can happen" mentality. That's why everyone here believes we'll have fully self-driving cars in 5-6 years.

In the rest of the engineering world, the answer to any question is: it'll be harder than you think it'll be (physics will beat you over the head at every step). You can cross your arms and say "that won't work" and you'll be correct 97% of the time. Fusion is something that some of the smartest people in the world, with enormous amounts of money behind them, have been beating their heads against for the last half century or more. Somebody will figure it out, eventually, but statistically, any given project is very likely not to be the one that does, and it will almost certainly take much longer than the optimists assume it will take.

Did you know that coal plants, which still make up the majority of U.S. energy production, are only about twice as efficient today than they were a century ago?

[1] Although math can be a kick in the ass too if you're working in domains where you can prove there are no polynomial-time algorithms for whatever problem you're working on. E.g. there is a reason people have been banging their heads on the garbage collection problem since the 1950's and it's still an active area of research.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#214

Post by ChuckMcM »

al2o3cr wrote: post #197
charonn0 wrote: post #175

Earlier quoted context omitted.

> the plasma leaks out of the ends of the magnetic containment According to this link[1] posted by another commenter, they create a "axisymmetric mirror by positioning zones of high magnetic field near each end of the vessel so that they reflect a significant fraction of plasma particles escaping along the axis of the CFR." [1]: http://aviationweek.com/technology/skunk-works-reveals-compa...

When you're dealing with a plasma at 20 million kelvin, the leftovers from that "significant fraction" that don't get reflected can really ruin your day... LLNL scientists almost tested a similar device (see 'MFTF') but the project was cancelled in 1986 before it was turned on.

Reminded me of a quote,

"It really is a vanishingly small amount of plasma that escapes from the device."

"What part of 'It is just like the Sun' did you not understand?"

Re: Skunk Works Reveals Compact Fusion Reactor Details

#215

Post by titanomachy »

nabla9 wrote: post #164

I'm not seeing any top physicists working in this program (McGuire is not one). I would be willing to bet 1000 EUR that their math and modeling does not add up, or they have skipped some details. Problem with fusion research like this is that the closer you get self sustainment or energy generation, the harder it gets and problems pile up. This project looks like many other similar projects that have gone bust. They…

"There aren't any top physicists working on this project" isn't really enough to dismiss it outright. The number of brilliant physicists is much greater than the number of top physicists, so it's not unheard of for major developments to come from someone who's not yet highly recognized. McGuire's an MIT Ph.D, so it's likely he's not a complete idiot.

I hope they have some novel ideas about neutron containment, though, otherwise you're right and this is project is not likely to yield the first economical fusion reactor.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#216

Post by cpwright »

rayiner wrote: post #213
jsmthrowaway wrote: post #194

Earlier quoted context omitted.

It's always a safe bet that the top Hacker News comment will always be "won't work, it's too hard." It's like sitting around for a year trying to sell a project at my current employer, with everybody and their lead telling you "that'll never work," then you implement in a weekend and those same people start nitpicking what you've come up with. (What happened to it'll never work? "Well, your CSS isn't great.") Honestl…

That's hardly ever true. In my experience, Hacker News is full of people from the software field; folks whose professions are often unconstrained by physics,[1] and who have a generally optimistic "this can happen" mentality. That's why everyone here believes we'll have fully self-driving cars in 5-6 years. In the rest of the engineering world, the answer to any question is: it'll be harder than you think it'll be (p…

> Did you know that coal plants, which still make up the majority of U.S. energy production, are only about twice as efficient today than they were a century ago?

There are certainly two ways of looking at that. The way I read your sentence it sounds very pessimistic. On the other hand, I look at that and say that over 100 year's we've managed to extract twice as much usable energy out of a pound of coal, through a variety of incremental improvements to what is fundamentally the same technology; and the world is a better place for it.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#217

Post by [deleted] »

rayiner wrote: post #213
jsmthrowaway wrote: post #194

Earlier quoted context omitted.

It's always a safe bet that the top Hacker News comment will always be "won't work, it's too hard." It's like sitting around for a year trying to sell a project at my current employer, with everybody and their lead telling you "that'll never work," then you implement in a weekend and those same people start nitpicking what you've come up with. (What happened to it'll never work? "Well, your CSS isn't great.") Honestl…

That's hardly ever true. In my experience, Hacker News is full of people from the software field; folks whose professions are often unconstrained by physics,[1] and who have a generally optimistic "this can happen" mentality. That's why everyone here believes we'll have fully self-driving cars in 5-6 years. In the rest of the engineering world, the answer to any question is: it'll be harder than you think it'll be (p…

[deleted]

Re: Skunk Works Reveals Compact Fusion Reactor Details

#218

Post by javajosh »

macinjosh wrote: post #211
protonfish wrote: post #207

Earlier quoted context omitted.

And it's always a safe bet the top response to that comment will be somebody criticizing it without any solid facts or reason but with fuzzy "you just need to believe harder!" kind of nonsense.

It is also a safe bet that the response to the original comment's response will be some guy saying how being hopeful about something is complete nonsense. It's turtles all the way down. Guess we should just give up on Internet commenting. /s

Interestingly, the heat for this pattern is always taken by the last comment, for some strange reason. Maybe it's the communities way of saying "Duh, we know this happens, and the way we stop conversations from going down the meta-toilet is to not have them." Although I would say it's more fair to downvote every comment that fits the pattern, to the root, rather than just the latter ones.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#219

Post by privong »

loarake wrote: post #202
privong wrote: post #188

Earlier quoted context omitted.

> How much dangerous are the neutrons from such device? Similar to radiation, worst? Neutrons are interesting in that they dump all their energy into a very small region. Instead of losing energy continually and gradually, they travel a ways and then dump all their energy into one spot. This makes them potentially very useful for things like cancer treatment (you can select neutrons to ensure they deliver most of the…

Are you sure you're not mixing up neutrons and protons? Here are some typical depth dose curves from google images( http://www.nap.edu/books/11976/xhtml/images/p20014b2bg205001... ). Neutrons, being neutral particles, don't exhibit the Bragg Peak (large increase in energy deposition at the end of the particle's track) that you get for heavy charged particles.

I was pretty sure neutrons beahved that way (recalling from a course I took in grad school), but it has been a few years, and I do not have references handy. I am not entirely sure what the y-axes are, on the plot you linked, so I am not sure how it correponds to what I was saying.

Re: Skunk Works Reveals Compact Fusion Reactor Details

#220

Post by [deleted] »

cpwright wrote: post #216
rayiner wrote: post #213

Earlier quoted context omitted.

That's hardly ever true. In my experience, Hacker News is full of people from the software field; folks whose professions are often unconstrained by physics,[1] and who have a generally optimistic "this can happen" mentality. That's why everyone here believes we'll have fully self-driving cars in 5-6 years. In the rest of the engineering world, the answer to any question is: it'll be harder than you think it'll be (p…

> Did you know that coal plants, which still make up the majority of U.S. energy production, are only about twice as efficient today than they were a century ago? There are certainly two ways of looking at that. The way I read your sentence it sounds very pessimistic. On the other hand, I look at that and say that over 100 year's we've managed to extract twice as much usable energy out of a pound of coal, through a v…

[deleted]
Post reply on HN