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Google revives controversial cold-fusion experiments

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Re: Google revives controversial cold-fusion experiments

#151

Post by criddell »

ars wrote: post #144
criddell wrote: post #73

Earlier quoted context omitted.

> Atoms are like little magnets that repel each other. Is that a good analogy? I wonder because the first thought that popped in my head is that magnets also attract each other.

> is that magnets also attract each other. Electrons attract atomic nuclei (which is the part of the atom that fuses), normally they are too far away to matter, but if you replace them with muons (which are basically heavy electrons) then you can actually help the atoms come close enough because the muon attracts both. Since the muon is heavier it orbits closer to the nucleus of the atom, which helps it cancel out th…

> Since the muon is heavier it orbits closer to the nucleus of the atom, which helps it cancel out the repelling force.

Even this is hard for me to wrap my head around when I try to also remember that these particles are really just quantum field phenomena.

Re: Google revives controversial cold-fusion experiments

#152

Post by magduf »

jayalpha wrote: post #125
magduf wrote: post #114

Earlier quoted context omitted.

I wear contact lenses. If I could instead wear lenses that continuously monitored my glucose level and it didn't cost me anything extra, and they still gave me the visual acuity of my normal lenses, why wouldn't I use that? I already wear them every day so for me, it requires zero effort. Having to get urine samples regularly, or worse, blood samples, is a LOT more work on my part (not to mention painful for the bloo…

"it didn't cost me anything extra" Good luck with that. How about people walking abound 24/7 with an anal plug?

Wow, that's an incredibly asinine comparison and comment. Millions of people walk around with contact lenses every day, myself included, and don't find them uncomfortable at all (or at least, much more comfortable than glasses). If they had an additional useful feature built into their lenses for no extra cost, I'm sure plenty of them would be happy to have it. If you don't like contacts, that's your issue, not mine.

Re: Google revives controversial cold-fusion experiments

#153

Post by AnthonyMouse »

dTal wrote: post #150
AnthonyMouse wrote: post #148

Earlier quoted context omitted.

Why not? If someone is buying power from coal instead of you when you have lower costs, that's money you're leaving on the table.

I'm sure there's lots of ways it could happen. Off the top of my head - you can't just snap your fingers and start selling power, you need to build the reactors, scale out infrastructure, etc etc. There's huge expenditure involved. If you have a giant pile of money in the bank, earning interest, it might not be worth your while to spend it on that. Another point - how much do you charge for the power? If your goal is…

> If you have a giant pile of money in the bank, earning interest, it might not be worth your while to spend it on that.

But that's the case either way. If the technology was public domain, somebody would still have to pay to build the reactors, and then it's even harder to raise capital because with more competition there is less profit.

> If your goal is to make money, the answer is "as much as you can".

But "as much as you can" really means "just under what existing alternatives cost" -- because getting people to switch is how you make money. You don't make money by losing customers to competitors.

Re: Google revives controversial cold-fusion experiments

#154

Post by grkvlt »

mikeash wrote: post #127
grkvlt wrote: post #123

Earlier quoted context omitted.

I'd believe Lockheed Martin's CFR claims more if they didn't say things like this: > Energy created through fusion is 3-4 times more powerful than the energy released by fission.[0] Which is just confus(ed/ing) on a fundamental level... More Powerful energy? So each Joule from fusion is actually 3-4 times better than each Joule from fission, in some way? I really can't work out what they are trying to say here. 0. ht…

I think they’re saying that a single fusion event produces 3-4x more energy than a single fission event.

But even that is pretty vague, since a single Uranium atom fission event releases about 200 MeV of energy, whereas most of the Hydrogen/Deuterium/Tritium/Helium/etc. fusion pathways release around 10% of this per fusion event: D + T -> He fusion gives 17 MeV, 4 p -> He gives 27 MeV, D + D -> He is 12 MeV and so on. Now, the energy released per nucleon greater for fusion, but I'm not convinced that's a useful or intuitive metric?

Re: Google revives controversial cold-fusion experiments

#155

Post by ars »

criddell wrote: post #151
ars wrote: post #144

Earlier quoted context omitted.

> is that magnets also attract each other. Electrons attract atomic nuclei (which is the part of the atom that fuses), normally they are too far away to matter, but if you replace them with muons (which are basically heavy electrons) then you can actually help the atoms come close enough because the muon attracts both. Since the muon is heavier it orbits closer to the nucleus of the atom, which helps it cancel out th…

> Since the muon is heavier it orbits closer to the nucleus of the atom, which helps it cancel out the repelling force. Even this is hard for me to wrap my head around when I try to also remember that these particles are really just quantum field phenomena.

Heavier means a smaller (shorter) wavelength, bend that wavelength into a circle around the nucleus, and it's smaller, since the circle is smaller, it's closer.

Re: Google revives controversial cold-fusion experiments

#156

Post by mikeash »

grkvlt wrote: post #154
mikeash wrote: post #127

Earlier quoted context omitted.

I think they’re saying that a single fusion event produces 3-4x more energy than a single fission event.

But even that is pretty vague, since a single Uranium atom fission event releases about 200 MeV of energy, whereas most of the Hydrogen/Deuterium/Tritium/Helium/etc. fusion pathways release around 10% of this per fusion event: D + T -> He fusion gives 17 MeV, 4 p -> He gives 27 MeV, D + D -> He is 12 MeV and so on. Now, the energy released per nucleon greater for fusion, but I'm not convinced that's a useful or intui…

How about energy per kilogram?

Re: Google revives controversial cold-fusion experiments

#157

Post by gliboc »

perl4ever wrote: post #134
gliboc wrote: post #118

Earlier quoted context omitted.

I'm returning your argument. Imagine your are driving your car on the highway, but you suddenly have a heart attack and become unable to remain conscious. Do you: (a) Die? (b) Die? Manned vehicles are not coming anytime soon. They are a whole slew of problems etc. -- you got my point. I think focusing too much on pesky details is very much a fallacy in this case - you do not want an "AI" to react like a human in all…

"Imagine your are driving your car on the highway, but you suddenly have a heart attack and become unable to remain conscious" Humans who drive cautiously may go for a million miles without an accident. The best self-driving cars (i.e. Waymo) disengage on average every 11,000 miles.[1] It seems to me that a disengagement is equivalent to becoming unconscious without warning, and presumably we both agree that a given…

It is an interesting metric, thank you for pointing it out. Until now I kept in mind the amount of miles between accidents, but surely both should be considered.

However, I think this metric could be irrelevant in the case of a home/work commute. The 11,000 miles average appears to have been obtained basically by randomly driving Waymo cars on Californian roads. But a usual commute is much less than 11,000 miles, and if your self-driving can do it by itself once then probably it can do it twice. As the article puts it:

"The value of the data is limited, however, as the figures don’t factor in the complexity of environments in which vehicles are tested–dense urban settings, versus low-speed suburbs or less complex highway driving–nor do they show conditions including weather, light or speed."

Nevertheless, you seem to have missed my point : I was arguing that coming up with a specific use-case example that may (or may not, actually) go wrong is an argument that goes both ways.

Re: Google revives controversial cold-fusion experiments

#159

Post by gnufx »

I've only skimmed this thread, but I don't see this perspective, in case people are still reading.

The common thread in practitioners of this stuff, and people attacking those who call it out as rubbish, seems to be rejecting nuclear physics while claiming to be observing (or supporting the possibility of) nuclear processes. I don't mean just established nuclear theory and experiment. Convincing evidence for reaction products is missing -- both nuclear and chemical ones -- and I'd expect detecting reaction products to be relatively easy compared with accurate calorimetry. People qualified to do make such measurements doubtless won't be considered sufficiently neutral, shall we say, about the physics. Anyhow, rather than say "it doesn't happen" they would be able to put a decent limit on the rate of such processes, whatever their a priori attitude. "Science doesn't care what you believe", as I recently saw on a T-shirt.

I remember when the Fleischmann and Pons stuff first appeared. It was so obviously pathological science that it didn't seem worth devoting resources towards it. Did you know that palladium is a particularly useful target for nuclear physics? Then I was doing spectroscopy on fusion reactions with it (and we had probably the best gamma-ray, neutron, and recoil nuclei detectors). There was no evidence of any anomalies associated with palladium. Apropos possibly burying evidence against established physics: those measurements demonstrated that the conventional wisdom about aspects of the processes was wrong. In contrast, I studied fusion reactions for which actual nuclear physicists presented evidence against the basic compound nucleus model; better measurements and calculations supported the model. The work was peer reviewed in the usual nuclear physics journals, of course.

Re: Google revives controversial cold-fusion experiments

#160

Post by vidarh »

thaumasiotes wrote: post #27
vidarh wrote: post #10

Earlier quoted context omitted.

There's an Iron Man story arc lone from a few years ago where Tony Stark starts a car company using his repulsor batteries as the energy supply..

Seems like a good example of https://tvtropes.org/pmwiki/pmwiki.php/Main/ReedRichardsIsUs... . No one ever thought cheap energy might be helpful before a few years ago? It's still not useful outside of cars?

The story line actually covers it quite well in having him struggle with the thought of whether or not he can make them safe enough (e.g. he's other places talked of the battery in his chest having the energy of a small sun) to make them accessible.

The story line in question comes after one where someone has scavenged his tech from broken parts of Iron Man armor and used them in terrorist attacks, and at the same time as he's put together a purely "defensive" Iron Man suit for Pepper Potts called Rescue, and he decides to rebuild his company around civilian applications of the underlying tech,

Iron Man is actually quite interesting in that respect, as a lot of the story lines delve into him struggling with whether or not he should produce weapons to stop bad guys or come up with a design to find a counter to them before a bad guy comes up with the same design, vs. finding civilian applications without inadvertently handing bad guys new weapons. Some of those story lines make poor arguments, but at least the Iron Man story lines are trying unlike FF, I feel, where it's "let's whip up something new amazing before breakfast and then never do anything with it", while Tony Stark grapples with the issues of commercializing his inventions all the time, and often has to deal with fallout from it.

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