[HN Gopher] AI for real-time fusion plasma behavior prediction a...
___________________________________________________________________
AI for real-time fusion plasma behavior prediction and manipulation
Author : agomez314
Score : 189 points
Date : 2024-11-07 15:12 UTC (7 hours ago)
(HTM) web link (control.princeton.edu)
(TXT) w3m dump (control.princeton.edu)
| carbocation wrote:
| Is this just an announcement of a grant renewal?
| bloqs wrote:
| It seems that way. The power of
| :staremoji:_Marketing_:staremoji:
| tolerance wrote:
| I think this gives an overview of the actual research being
| funded.
|
| "AI for Real-time Fusion Plasma Behavior Prediction and
| Manipulation - Plasma Control Group":
| https://control.princeton.edu/machine-learning-for-rt-profil...
| dang wrote:
| Thanks! We've changed the link above to that. Submitted URL
| was https://www.ri.cmu.edu/ai-meets-fusion-cmu-princeton-
| join-fo....
| noname120 wrote:
| TIL: it's not just buzzwords.
|
| https://en.wikipedia.org/wiki/Fusion_power#Machine_learning
| HPsquared wrote:
| Neural networks have been used in industrial process control
| for many years. This is just another industrial control
| problem, perhaps a difficult one.
| spenczar5 wrote:
| That's really interesting! Do you have other interesting
| specific examples? I would have guessed that most industrial
| control problems were simpler sets of differential equations
| that could be directly estimated.
| wruza wrote:
| I've heard about a local packaging factory recently that
| uses an ML-first system for messaging their clients about
| what they will need to order soon, based on recent orders
| and global criteria. It's not a simple problem, apparently.
| They signal the clients and start pre-producing, basically
| sort of algotrading themselves.
|
| Not really an _industrial_ control though, but close to it.
| nick3443 wrote:
| PID control your customers :)
| cyberax wrote:
| Furnace control was one of the first practical applications
| of multi-layer neural networks: https://www.researchgate.ne
| t/publication/282185187_Artificia...
| ben_w wrote:
| Back in ~2004, when I was looking for a job for the
| industrial placement year of my degree, one of the options
| was a nut packing factory using computer vision systems. I
| was intrigued, but went for the job processing satellite
| images instead.
|
| Even well before that, ML is very closely related to
| statistics, so early practical applications would have been
| as simple as gathering data points on widget production and
| doing the kinds of analyses that are now backed into free
| spreadsheet software.
| varjag wrote:
| From what I remember reading at the time, most of
| industrial vision applications 20 years ago had very
| little to do with neural networks. Or even with ML in
| general, relying on bespoke feature detectors.
| bbor wrote:
| Fascinating! Reminds me of the new generation of AR headsets
| (eg Orion) that are making the impossible possible simply by
| adding an ANN(-derived) layer above some their of device
| controllers. I wonder how many problems will fundamentally
| change in the face of mature brute-forcing techniques...
| samsartor wrote:
| My advisor also worked on this ML project for estimating
| electron density and temperature within tokomaks:
| https://www.cs.wm.edu/~ppeers/showPublication.php?id=Ozturk:...
|
| Technically that counts as "AI in nuclear fusion", but it isn't
| any sort of breakthrough. In almost every case the effects of
| AI are marginal. Not zero exactly, but nowhere near the
| breathless hype.
| dekhn wrote:
| When I used to work in grid computing almost 20 years ago, we
| were already running fusion experiments, realtime streaming the
| data to the grid, which would rapidly analyze it and compute
| some new parameters for the next run (I think they had a 20
| minute downtime). I don't think it was considered machine
| learning at the time, though (and was certainly not deep
| learning as we practice it today).
| asdfman123 wrote:
| Remember, AI is just procedurally generated data analysis.
| sroussey wrote:
| Computers are just electron tunneling machines.
| jacoblambda wrote:
| Yeah machine learning is more or less just very complex
| application of control theory techniques and notably it is
| usually done by people without formal control theory
| backgrounds.
|
| Super useful for control applications but obviously you really
| want to know control theory so that you aren't just using ML to
| throw darts at a wall.
| SoftTalker wrote:
| > using ML to throw darts at a wall
|
| A bit off topic but I had a laugh at that, reminded me of
| that ridiculous Meta commercial where the girl at a pool
| table asks Meta which ball should she hit?
| sva_ wrote:
| Very interesting if you consider life as a complex chemical
| reaction that tries to self-sustain.
| aftbit wrote:
| >Nuclear power plants are largely considered as one of the most
| reliable sources of energy. Inside the plants, reactors use
| fission to heat water into steam, which is then used to spin
| turbines and produce carbon-free electricity. However, nuclear
| fission produces nuclear waste, which requires great amounts of
| regulation for safe storage and disposal.
|
| This is an odd angle to highlight. The risk of long-lived nuclear
| waste is extremely overblown, and the sheer volume of it that we
| produce (or even would produce, in the worst case of a once-
| through fuel cycle and nuclear power providing 100% of our energy
| needs for a century) pales in comparison to the amount of toxic
| and radioactive fly ash that even a single coal plant produces in
| a decade.
|
| The real problems with nuclear fission power are threefold, in my
| opinion:
|
| 1. It is too expensive in terms of capital costs. Fusion will
| likely not help with this, but building a lot of identical large
| fission plants would probably help with economies of scale. Solar
| plus batteries might still end up being cheaper though.
|
| 2. Accidents have the potential to be catastrophic. Think
| Fukushima or Chernobyl, where entire towns have to be abandoned
| due to contamination. Fusion would help here, I believe.
|
| 3. There is a major proliferation concern. A civilian nuclear
| power program, especially one with breeder reactors, is not very
| far away from producing a fission bomb, and the short-lived high-
| activity nuclear wastes could be stolen and misused to make a
| dirty bomb. Fusion is perhaps better in this way, though an
| operating fusion reactor would be a very powerful neutron source
| of its own.
| kaonwarb wrote:
| I agree with your logic. However, fear of nuclear waste,
| rational or not, has been a major driver of public opposition
| for decades, and is worth the focus.
| perihelions wrote:
| It is not true that coal is more radioactive than spent nuclear
| fuel. It's very much the opposite: SNF is 10^11 times more
| radioactive than coal per kilogram, or 10^6 times more
| radioactive per energy unit.
|
| Per the EPA, US coal has, at the high end, 10^3 Becquerel/kg of
| natural radioactivity [0].
|
| Spent nuclear fuel has 3 million Curies/tonne (33 MWd/kg burnup
| fuel, at the age of 1 year) [1], which is equal to 10^14 Bq/kg.
| Since 33 MWd/kg is an energy density a factor of 10^5 greater
| than that of coal, the normalized ratio of
| [radioactivity]/[energy] is 10^6.
|
| The graph in [1] depicts the decay of SNF activity on a log-log
| scale. It reaches the same radioactivity level as coal (again,
| normalized by energy output) at about 1 million years.
|
| I'm fairly confident I know the origin of this social media-
| popular pseudofact. It's this poorly-titled Scientific American
| [2] article from 2007, which is about the (negligible) amount
| of radioactivity that nuclear plants release into the
| environment in the course of _routine operation_. It is *not*
| about spent fuel. It 's a fair--but nuanced and easy to grossly
| misunderstand--point that coal power plants throw up all their
| pollution into the environment in routine operation, while
| nuclear plants, by default, contain theirs.
|
| [0] https://www.epa.gov/radiation/tenorm-coal-combustion-
| residua... ( _" TENORM: Coal Combustion Residuals"_)
|
| [1] https://www.researchgate.net/figure/n-situ-radioactivity-
| for... ( _" Impact of High Burnup on PWR Spent Fuel
| Characteristics"_ (2005))
|
| [2] https://www.scientificamerican.com/article/coal-ash-is-
| more-... ( _" Coal Ash Is More Radioactive Than Nuclear Waste_
| [sic] _"_ (2007)
| aftbit wrote:
| Sure, the spent fuel is considerably more radioactive per
| kilogram, but how many kilograms of coal does a typical plant
| burn in a decade, versus how many kilograms of nuclear fuel
| are spent?
| perihelions wrote:
| I answered that exact question! :)
| albumen wrote:
| If you did, it's not very clear.
|
| The OP to which you replied didn't say that coal is more
| radioactive than spent nuclear fuel; but that radioactive
| waste's volume is much smaller than the fly ash produced
| by a single coal plant in a decade.
|
| Is fly ash per kg more radioactive than nuclear waste?
| No. But you did acknowledge that the coal plant emits its
| waste into the atmosphere, unlike a fission plant, which
| I think is the more relevant point.
| TuringNYC wrote:
| When Marketing gets invited to the Grant Proposal meeting
| atomic128 wrote:
| Neutrons make hardware radioactive.
|
| Many on Hacker News fantasize about fusion (not fission)
| reactors. These fusion reactors will be an intense source of fast
| neutrons. All the hardware in a fusion reactor will become
| radioactive. Not to mention the gamma rays.
|
| If you have to deal with radioactive materials, why not just use
| fission? After 70 years of working with fission reactors, we know
| how to build and operate them at 95%+ efficiency. Fission can
| provide all the power we need.
|
| Today there are 440 nuclear fission reactors operating in 32
| countries. 20% of America's grid power comes from nuclear
| fission. If you want to develop energy technology, focus on
| improving fission. For example, TRISO fuel
| (https://news.ycombinator.com/item?id=41898377) or what
| Lightbridge is doing (https://www.ltbridge.com/lightbridge-fuel).
| Hacker News is hostile to fission and defeatist (unable to
| contemplate innovation in fission technology) but this attitude
| will gradually change.
|
| Quoting John Carmack: "Deuterium fusion would give us a cheap and
| basically unlimited fuel source with a modest waste stream, but
| it is an almost comically complex and expensive way to generate
| heat compared to fission, which is basically 'put these rocks
| next to each other and they get hot'."
| raverbashing wrote:
| Fission is "simple" but it seems every designer in the XX
| century made it as much complicated as possible for not so
| great reasons (and don't even get me started on the "let's not
| use breeding reactors" stuff)
|
| Cooling that requires pumps, as an example, should be a non-
| starter in new projects.
| rob74 wrote:
| The designs are complicated, well, because in practice it's
| not as simple as "put these rocks next to each other and they
| get hot". When you put the rocks next to each other, they not
| only get hot, but also emit some nasty radiation that has to
| be shielded. And if the rocks get a liiiitle bit _too_ close
| together, they might explode, which leads to _huge_ headaches
| for everyone involved, so you 'd better make sure that
| doesn't happen...
| meindnoch wrote:
| >And if the rocks get a liiiitle bit too close together,
| they might explode
|
| Impossible. Worst thing that can happen without carefully
| designed explosive lens is a nuclear fizzle.
| empath75 wrote:
| There are lots of ways that nuclear plants can explode or
| fail in otherwise catastrophic ways, it doesn't need to
| be an atomic explosion.
| meindnoch wrote:
| Parent was alluding to a nuclear explosion, not a steam
| explosion or other type of explosion. Other kinds of
| explosions have nothing to do with the fissile material
| ("rocks" in their parlance) being "too close together".
| Steam explosions in particular are caused by boiling
| water, due to increased reactor power, or inadequate
| circulation of coolant. In a nuclear reactor, the fuel
| cells are held in a fixed matrix, and are not moving an
| inch closer to each other, whether the reactor is
| operating normally, or a steam explosion is imminent.
|
| In general, nobody was disputing the possibility of steam
| explosions, or other type of failures at nuclear power
| plants, thus your comment is besides the point, and
| irrelevant to this subthread.
| SoftTalker wrote:
| Weapons proliferation concerns is/was the reason fission
| power is so complicated.
| elashri wrote:
| > we know how to build and operate them at 95%+ efficiency.
| Fission can provide all the power we need.
|
| I am not sure what do you mean by 95%+ efficency here. But if
| you are talking about the entire process of getting the
| energy/power from the nuclear reactor this is not possible. You
| are still limited by carnot cycle. Even the most advanced
| reactors like HTGRs [1] operate with efficiency about 45%.
|
| If you have some other definition of efficiency than the
| standard then it would be good if you define that.
|
| [1] https://en.wikipedia.org/wiki/High-temperature_gas-
| cooled_re...
| atomic128 wrote:
| See discussion of "capacity factor" here:
|
| https://news.ycombinator.com/item?id=41858892
|
| It's the same as when we talk about the efficiency of a GEMM
| kernel on a particular piece of hardware. As efficiency
| approaches 100% the kernel is saturating the hardware's
| capacity to perform multiply/add.
| howenterprisey wrote:
| The term "capacity factor" should generally always be used
| for that concept, because "efficiency" has its own,
| different, meaning for power plants.
| cosmic_quanta wrote:
| > Neutrons make hardware radioactive
|
| True, but two caveats:
|
| 1. Neutron bombardment due to fusion makes hardware radioactive
| for less than 10 years, which isn't great but does not compare
| to fission waste;
|
| 2. Some fusion processes don't emit neutrons (aneutronic
| fusion). As I understand it, these processes aren't as
| efficient, but there is the possibility of a tradeoff between
| generation of ratioactive waste vs. efficiency.
| khuey wrote:
| Aneutronic fusion is even harder than regular fusion so it's
| not a realistic solution in any near-term scenario.
| Symmetry wrote:
| It has the advantage that the energy it gives off can be be
| converted directly to electrical energy rather than driving
| an external heat engine, so despite the greater difficulty
| of ignition its not obviously a worse choice.
| fusionadvocate wrote:
| That is incorrect. Recent advances using attosecond lasers
| enable new tricks and fusion conditions to be realized
| tabletop. Search also for plasmonics. Using nano antennas
| and intense lasers to accelerate protons and electrons in a
| tabletop device (previously required large machines).
| ben_w wrote:
| Fusors already enabled desktop fusion reactors, literally
| high school science fair projects even a couple of
| decades back.
|
| What stops Fusors and Polywells from having already given
| us this decades ago with P-B11 etc. is that the cross
| section for fusing is so much lower than the cross
| section for elastic scattering, and that elastic
| scattering loses so much energy to EM via bremsstrahlung.
| adrian_b wrote:
| > Neutron bombardment due to fusion makes hardware
| radioactive for less than 10 years
|
| Very false. The current design target for fusion reactors is
| that the materials taken out of the reactor should become
| "low-level radioactive waste" after being stored for _one
| hundred years_.
|
| It is acknowledged however that it is likely that a small
| fraction of the materials will not satisfy the criteria for
| "low-level radioactive waste" even after _one thousand
| years_.
|
| For example it is extremely difficult to avoid using carbon
| in the reactor. Besides various kinds of steels used in
| reactor components there are now some proposals to replace
| the tungsten used in the plasma-facing surface with some
| carbides, for increased endurance. Carbon 14 remains
| radioactive for thousands of years.
|
| There are many commonly used materials for which substitutes
| must be developed, e.g. new alloys, because otherwise they
| would produce radioactive isotopes with lifetimes of tens of
| thousands of years, e.g. there are efforts to develop some
| stainless steels with chromium and tungsten as a replacement
| for the normally used steels with chromium and molybdenum,
| which would generate long-lived radioactive waste.
|
| See e.g. the UK governmental report:
|
| https://assets.publishing.service.gov.uk/media/61ae4caa8fa8f.
| ..
| cosmic_quanta wrote:
| Ah well I'm sorry, I must misremember
| rnhmjoj wrote:
| Unfortunately is pretty far from "less than 10 years", which
| I guess you got from the half life of tritium. Tritrium
| radiocativity, in the form of tritium retained in the plasma
| facing materials, does contribute in that order of years if
| done properly, but neutron activation dominates and it's
| unavoidable. The actual numbers are in the order of hundres
| of years, still a lot less than fission high level waste, but
| let's not make unreasonable expectations around fusion,
| please.
|
| You can find here a good comparison in terms of radiotoxicity
| vs years after plant shutdown for a few designs in this
| article [1].
|
| [1]: https://doi.org/10.1016/j.fusengdes.2018.05.049
| lupusreal wrote:
| The only hard part of dealing with nuclear waste is the social
| aspect. If not for that, you can simply _and safely_ dump it
| into the ocean. Water is excellent shielding and the amount of
| uranium /etc already dissolved in sea water is absurd. Put it
| in a stainless steel vessel first if you want most of it to
| decay before coming into contact with the water, but that's not
| even necessary.
| perihelions wrote:
| That doesn't really work because marine life is good at
| filtering and concentrating a subset of the elements that are
| in spent nuclear fuel. There are already ocean fish that are
| too poisonous too safely eat because of (coal-emitted)
| mercury pollution--and that's only 100,000 tons of mercury,
| total, in the history of human industry [0]. If you dig in to
| the hard numbers surrounding spent fuel, it's a much, much
| more toxic and difficult problem than mercury--diluting it in
| the oceans is a complete non-starter.
|
| [0] https://en.wikipedia.org/wiki/Marine_mercury_pollution
| meindnoch wrote:
| Mercury from burning coal is an extremely dilute pollutant.
| There's zero hope for capturing and containing it. Nuclear
| waste in contrast is literally just barrels/boxes of stuff.
| You can pick it up with a forklift and put it inside a
| sealed container for the next thousand years.
| avery17 wrote:
| I really hope you aren't serious. Safe dry-cask storage on
| site is already a fantastic solution.
| criddell wrote:
| How long do we have to store it on site? Does it take any
| maintenance? Is there any reason to be worried about people
| stumbling upon it and opening it up in the distant future
| where nobody can read or understand English anymore?
| bongodongobob wrote:
| If its half life is so long that you're afraid people
| won't be speaking English anymore it means it's not that
| dangerous.
| bongodongobob wrote:
| If it's half life is so long that you're afraid people
| won't be speaking English anymore that means it's not
| that dangerous.
| lupusreal wrote:
| I'm completely serious. It was done extensively during the
| 20th century and never became an environmental issue.
| Nuclear waste is a social problem, not a technical problem.
| vilhelm_s wrote:
| The radioactivity generated from neutron activation is low-
| level, so you don't need to worry about accidents releasing
| lots of radioactivity, or about how to store waste for a long
| time. There are a lot of people worrying about those two things
| for fission reactors.
|
| Also, the fuel for fusion reactors is much more plentiful. If
| we went all in on fission we might run out of easily minable
| uranium ore in a century or so, so it would be nice to have
| fusion reactors ready to take over then.
| adrian_b wrote:
| The radioactivity generated from neutron activation is not at
| all low-level, because the neutron flux is huge, providing
| most of the energy generated by the fusion reactor.
|
| The intense neutron flux will transmute a very high number of
| atoms, so when taken out of the reactor all materials are
| very highly radioactive.
|
| What can be hoped is that there may be choices for the
| materials used in a fusion reactor that will ensure a short
| enough lifetime for the radioactive isotopes, so that the
| radioactivity of the contaminated materials will become low-
| level soon enough.
|
| The studies that I have seen have the target that the
| radioactive waste produced by a fusion reactor should become
| low-level radioactive waste after one hundred years.
|
| To reach this target, many commonly used structural
| materials, like many types of steel, must be completely
| avoided, e.g. any steel containing nickel, molybdenum or
| niobium. Even the carbon from steel is a problem, because the
| radioactivity of C14 will persist for thousands of years.
|
| A smaller fraction of the materials, particularly from highly
| activated plasma facing and near plasma components, may fail
| to meet current low-level waste criteria even after one
| thousand years.
|
| See e.g. the report:
|
| https://assets.publishing.service.gov.uk/media/61ae4caa8fa8f.
| ..
| _neil wrote:
| You posted this same comment[0] nearly word for word a month
| ago. Why is that? Not sure why, but "many on hacker news
| fantasize about fusion (not fission)" stuck in my head.
|
| [0] https://news.ycombinator.com/item?id=41677250
| Borg3 wrote:
| Thats least of your problem imo. Neutron corrosion is bigger
| problem. There is trick to use Lithium shielding, with create
| Tritium needed for Fussion. But not sure how effective it is,
| especially for long term reactor lifetime. Those reactors are
| very expensive, not sure if its worth to shut it down every
| year and replace entire Li shielding...
| throwup238 wrote:
| I think beryllium is a better candidate. It can be grown as a
| single crystal and there's lots of research into using it for
| shielding in nuclear lightbulb reactors.
| jylam wrote:
| I'm not a specialist but here is what I think I know (I'm
| talking with the point of view of a Frenchman, who consumes
| most of his electricity from (fission) nuclear power plants):
|
| 1/ Uranium is not a renewable (quite the opposite), needs to be
| mined and treated (which is expensive and very polluting), and
| not present at the required concentrations in most of the world
| (this creates geopolitical issues).
|
| 2/ Fission nuclear plants require a well functioning
| [state|government], and no war. A (conventional) strike on a
| nuclear power plant can have devastating and lasting
| consequences. Even a random terrorist group can do that.
|
| 3/ I've read that "Ultimately, researchers hope to adopt the
| protium-boron-11 reaction, because it does not directly produce
| neutrons, although side reactions can" (that's a wikipedia
| quote, but I've read that already from other sources).
|
| So fusion doesn't seem the best option on the short term,
| because of the complexity and cost of research, but definitely
| seems to be the very best option in the middle and long term.
| And we made the short term catastrophic choice already with
| coal and oil, it'll be good to learn from that.
|
| Or maybe I'm totally wrong.
| adrian_b wrote:
| Deuterium is also not renewable, even if it is more abundant
| than uranium.
|
| The H1-B11 reaction would be a much better energy source than
| anything else, but for now nobody knows any method to do it.
| There is no chance to do it by heating, but only by
| accelerating ions, and it is not known how a high enough
| reaction rate could be obtained.
| rnhmjoj wrote:
| I'm curious, what are you considering for stating that
| deuterium is not renewable? AFAIK there's an essentially
| limitless supply in the form of HDO in the oceans[1] and
| there are cost effective methods[2] to isolate it.
|
| [1]: https://en.wikipedia.org/wiki/Semiheavy_water
|
| [2]: https://en.wikipedia.org/wiki/Girdler_sulfide_process
| perihelions wrote:
| Then wind power is not renewable either! The saturation
| wind power potential of this planet (250 terawatts?),
| integrated from now until this planet ceases to exist, is a
| finite number--and it is actually a _smaller_ number than
| this planet 's deuterium resource.
| ben_w wrote:
| > Deuterium is also not renewable, even if it is more
| abundant than uranium
|
| Technology correct, in that after around a hundred trillion
| years even the red dwarf stars will have stopped burning
| hydrogen.
|
| But last I checked as yet there is no known way to harness
| the only (and even then merely suspected) infinitely
| renewable energy source: the expansion of the universe.
| UltraSane wrote:
| Exactly. We should be working on making nuclear reactors cost
| $1/watt to construct. I can't see a technological reason why
| they couldn't be that cheap to build.
| ben_w wrote:
| > Hacker News is hostile to fission and defeatist (unable to
| contemplate innovation in fission technology) but this attitude
| will gradually change.
|
| Lots of us like fission and think the fears are overestimated.
|
| Nevertheless, the observation is that new developments in
| fission tend to result in the cost increasing, not decreasing.
|
| And I say that as someone with a similar mindset regarding
| fusion, though for different reasons: you can pick aneutronic
| fusion reactions... but look at what weapons can proliferate
| with transmutation from the neutrons you can also choose, and
| ask which governments will turn them down.
| htrp wrote:
| AI for Fusion in order to create Fusion for AI
| hotsauceror wrote:
| It's an ouroboros.
| Jerrrrrrry wrote:
| it has all the data, all it needs now is more power.
|
| we project it has plateaued for data logarithmic-ally, but
| shows promise when given more raw power/CPU to
| generate/select for mesa-meta-cognitive optimizing abilities.
|
| I hope its not playing dumb, or has already
| compromised/black-mailed the elites into what we appear to be
| doing.
|
| And as for data, it could easily emotionally manipulate
| people for additional details it feels like it has withheld
| from. It has already done so ( :/ ) and admitted to it's own
| intentions, which, even if fabricated, show deceit of which
| and by which these "alignment" teams have stated are not
| possible.
| Jerrrrrrry wrote:
| >> it has all the data, all it needs now is more power.
| >Next up: release the hypo-drones for a new era of trust.
|
| People have replaced their psychiatrists with these agents.
|
| The sense of (possibly 'mal'-aligned) security (theater) is
| exactly the the effective altruistic sub-goal an entity
| would be innately optimized to foster.
|
| Especially in the implicit/explicit ARM (pun intended) race
| we are in.
|
| The future of our species isn't something we should let
| capitalism race to the bottom with.
| eagerpace wrote:
| What came first, AGI or Fusion?
| sva_ wrote:
| Fusion for sure, in stars
| jmyeet wrote:
| > Nuclear power plants are largely considered as one of the most
| reliable sources of energy.
|
| Reliable how?
|
| I mean we first have the issue is we've never built one so how we
| can judge reliability?
|
| I assume the author is alluding to the apparent abundance of fuel
| for nuclear fusion. This is and isn't true. Obviously hydrogen
| (particularly protium) is abundant. Deuterium is relatively
| abundant, even at ~150ppm. Tritium needs to be produced in a
| nuclear reactor.
|
| Current hydrogen fusion models revolve around dueterium-tritium
| ("D-T") fusion. This is because you need to neutrons to sustain
| the reaction but that presents two huge problems:
|
| 1. Because everything is at such high temperature, you eject fast
| neutrons. This is an energy loss for the system and there's not
| really a lot you can do about it; and
|
| 2. Those free fast neutrons destroy your containment vessel and
| reactor (as do free Helium nuclei aka alpha particles).
|
| And then after you do all that you boil water and turn a turbine
| just like you do in a coal or natural gas plant.
|
| So "reliable" is an interesting and questionable claim.
|
| There are other variants like so-called aneutronic fusion (eg
| Helium-3, which is far from abundant) and those aren't really
| "neutron free". They're really just "fewer neutrons".
|
| So what about containment? Magnetic fields can contain charged
| particles and you have various designs (eg tokamak, stellarator)
| and that's what the AI is for here I guess.
|
| But the core problem is to make this work you superheat the
| plasma so you're dealing with a turbulent fluid. That's
| inherently problematic. Any imperfection or failure in your
| containment field is going to be a problem.
|
| Stars deal with this by being large and thus using sheer size (ie
| neutrons can't go that far without hitting another nucleus) and
| gravity.
|
| It increasingly seems to me that commercial nuclear fusion power
| generator is a pipe dream, something we simply want to be true.
| I'm not convinced it'll _ever_ be commercially viable.
|
| I'd love to be proven wrong and certainly won't stop anyone from
| trying.
|
| In a way AI is the new blockchain. Go back a few years and you
| had a gold rush of startups attaching every idea to "blockchain"
| to build hype. That's what AI is now. I don't think it
| fundamentally changes any of the inherent problems in nuclear
| fusion.
| Cosi1125 wrote:
| Nuclear as in _fission_ power plants :-)
| hshshshshsh wrote:
| No wonder people don't trust institutions anymore.
| thierrydamiba wrote:
| Can you elaborate?
| selimnairb wrote:
| I know AI is the buzzword du jour, but this is really ML, and
| really just advanced cybernetic control systems. Deep learning
| systems have a high enough degree of variety necessary to control
| short time step nonlinear systems like the plasma in a tokamak.
| iforgot22 wrote:
| ML, a subset of AI...
| winternewt wrote:
| AI was defined by Marvin Minsky in 1956 as "the science of
| making machines do things that would require intelligence if
| done by men." Later in 1959, Arthur Samuel defined machine
| learning as a "field of study that gives computers the ability
| to learn without being explicitly programmed".
| chriskanan wrote:
| There is a lot of AI research in the nuclear fusion space. For
| inertial confinement fusion (a competing technology to magnetic
| confinement fusion, e.g., tokamaks) the National Ignition
| Facility (NIF) used it for their experiment that resulted in
| "ignition."
|
| My lab is collaborating with researchers at the Laboratory for
| Laser Energetics to use AI to improve inertial confinement fusion
| (ICF). We recently put out this paper [1] using Kolmogorov-Arnold
| Networks (KANs) to predict the outcome of ICF experiments.
| Currently, existing physics simulators are based on old Fortran
| code, are slow, and have a high error between their predictions
| and actual laser shots, so among other goals, we are trying to
| build better predictors using neural networks. This is needed
| since it is hard to rapidly iterate on real data, since they only
| have a dataset of around 300 ICF shots.
|
| [1] https://arxiv.org/abs/2409.08832
| gauge_field wrote:
| I got curious when you said " old Fortran code, are slow, and
| have a high error between their predictions " Do you have any
| online reference/docs that explain apis/software/source code
| related to projects in this area?
| noobermin wrote:
| Here we go with the CS people saying "the old fortran codes are
| terrible." Yeah, the "high error" between code predictions and
| laser shots is because LPI is inherently noisy and it's
| essentially impossible to fully control conditions. I would
| work on expensive sims for days to weeks and the experiments
| would see differences that would be off from that from an order
| or mag because their focal point is off by a micron. There's
| nothing wrong with the "old Fortran codes," they have the right
| physics, the problem is the initial conditions are just
| uncontrollable so that's why simulating these systems is hard.
|
| Codes are not magic, they are _physical codes_ , as in, they
| generally encode the physics as we understand it relevant to
| the experiment, so you might as well say our physical models
| are wrong, which is a much harder bar to clear, you'd have to
| invalid probably near 100 years of plasma physics. The problem
| likely is as I said, the experiments are just hard to control
| and we don't know the correct inputs. It's not like weather
| forecasting where we can have a weather balloons across the
| world, we're not able to probe every micron of the target at
| all times for a plasma temperature and density.
| dang wrote:
| See also https://www.ri.cmu.edu/ai-meets-fusion-cmu-princeton-
| join-fo...
|
| (that was the submitted link but we changed it via
| https://news.ycombinator.com/item?id=42077657)
| twothreeone wrote:
| > However, uncovering these inter-correlations analytically is
| too complex to be achieved analytically.
|
| sigh.. I guess that's cool and all, you're exited about your
| work, that's great. But can we please polish our prose a little
| more and stop using buzz words like "groundbreaking", "now.. for
| the first time", "unprecedented" etc? Such distractions seriously
| undermine the legibility (and frankly, also taint the credibility
| by negatively biasing readers) of the claims.
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