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Google revives controversial cold-fusion experiments

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Re: Google revives controversial cold-fusion experiments

#121
post #71

Earlier quoted context omitted.

So, you must think one of two things, then: 1. Google, with all of the subject matter expertise they can avail themselves of, is completely wasting their money on this research that has no hope of success. 2. It'd be a bad thing for the world if we got cold fusion, but Google made some money off of it. Is that right?

This tabletop research is orders of magnitudes cheaper than hot fusion. It's a huge reward for tiny risk.

Ah, yes, the good old Pascal's mugging[1].

I am aware that cold fusion experiments are both much cheaper, and if successful, considerably safer and cheaper than hot fusion. Yet, there is no plausible mechanism for fusion to occur at room temperature. For two protons (hydrogen ions) to fuse, they must be brought to within 10e-15 m of one another. This requires overcoming the Coulomb repulsion between the two positively charged protons. This in turn requires a great deal of energy, roughly 6 KeV even once quantum tunneling is taken into effect. This corresponds to velocities of roughly 10e6 m/s, or roughly 0.5% the speed of light. This is is called the Gamow energy or the Gamow peak[2]. In hot fusion, this is accomplished by heating a gas to something like 10e7 K, at which point the average energy of any given proton in the plasma is roughly 6 KeV. Not coincidentally, this is also roughly the interior temperature of stars. It has been shown time and again that fusion does occur in a tokamak reactor... just not quite fast enough to overcome the cost of creating and containing the plasma.

At room temperature, the fraction of protons traveling at 0.5% of the speed of light is zero for all intents and purposes. Thus, spontaneous does not normally occur at room temperature, which we can all agree on. For cold fusion to proceed, there needs to be some other mechanism capable of making up this difference, either by somehow accelerating protons to an extremely high velocity, or otherwise encouraging them to fuse, perhaps by lowering the Coulomb barrier by some unknown mechanism. For the Fleischmann–Pons experiment (the original "cold fusion" experiment in the 1980s) this was hypothesized to be achieved by the crystal structure of palladium[3]. However, after the failure to replicate the original experiment, this hypotheses appears to have been falsified. In fact, no experiment has ever shown a measurable rate of fusion occurring at low temperatures.

And yet, there is the precedent of the Gamow factor. The classical potential for the Coloumb barrier is 3.4 MeV. Therefore, in a purely classical model, it is literally impossible to get two protons to fuse unless they collide at close to the speed of light. Yet Gamow showed that fusion could occur, with some probability, at much lower energies, thanks to a well known phenomenon called quantum tunneling. Why could there not be some other way taking this further? Furthermore, there is the precedent with fission. In the 1930's, many notable scientists were fission could ever be used as a power source. They were aware that fission could be effected by alpha particle bombardment, but this did not seem "energy positive." Sound familiar? And yet, when Hahn and Meitner[5] discovered spontaneous nuclear fission occuring due to a chain reaction in uranium in 1938, it immediately became apparent it could be used as a massive source of energy, and Einstein immediately warned FDR and the Manhattan project began.[4] Why could not a similar story play out for fusion? Cold fusion is tantalizingly plausible and the experiments, as you say, can be conducted on a tabletop. Why not try?

My answer, which is of course a subjective judgement, is that good science happens by searching where the light is, exploring the implications and edges of existing theories, not out in the dark, trying things completely at random. Rutherford wasn't bombarding gold foil for the hell of it. Randomly trying things in an atheoretic way in the hopes that a previously undiscovered and unsuspected piece of new physics will drop out is closer to alchemy, and just about as likely to be successful. More than 2,000 years of randomly combining urine and lead resulted in not one ounce of gold. (I grant you that tabletop cold fusion experiments may very well find a new bit of chemistry.) But the argument against is simply this: 6 KeV. It's simply too much. No chemical or electrical process is going to get you that, unless it first turns your experiment into plasma, in which case you're back to hot fusion! It's like throwing pebbles at the moon and calling it the Apollo program. It's not a matter of just getting the right pebble. You can try quartz and obsidian, rough and smooth, for as long as you like, but you're not even beginning to address the invariant in the room, which is that you just can't impart enough kinetic energy to your pebbles to even get them out of Earth's gravity well, much less to the moon. That is why I believe that a dollar spent on cold fusion actually has lower expected payoff than a dollar spent on hot fusion.

[1]: https://en.wikipedia.org/wiki/Pascal%27s_mugging

[2]: https://en.wikipedia.org/wiki/Gamow_factor

[3]: https://en.wikipedia.org/wiki/Fleischmann%E2%80%93Pons_exper...

[4]: https://en.wikipedia.org/wiki/Einstein%E2%80%93Szil%C3%A1rd_...

[5]: https://en.wikipedia.org/wiki/Otto_Hahn#Discovery_of_nuclear...

Re: Google revives controversial cold-fusion experiments

#122

Earlier quoted context omitted.

As a Tesla owner, I have to say that I'm really looking forward to them delivering the Full Self Driving option that I paid for 18 months ago when I bought my car.

The worst part is, it doesn't seem like they'll be able to. I'm curious what happens if they ultimate need additional / different sensors to make it happen. Do they replace those parts for free?

My understanding is that FSD will at least require a new computer module, which they are supposed to replace for free for those of us who have purchased FSD.

However, it is an open question whether or not it will require additional / different sensors (like lidar).

Re: Google revives controversial cold-fusion experiments

#123
post #58
post #46

The cynicism in this threads hurts. > “This is not just a chase for cold fusion,” says Matthew Trevithick, a research programme manager at Google in Mountain View, California. “If it were, I don’t think we would have maintained an interest of this calibre of team for so long.” Here's what I see: fusion power would be a step function in human civilization. Such step functions are pathologically hard to achieve, becaus…

The skepticism is not about fusion power, it's about cold fusion specifically, as well role of proprietary IP and patents in scientific research. Tokamak[1] (and other magnetic confinement) reactors seem much more promising and have seen slow but non-zero improvements for decades[2]. Some reactors like JT-60 have come close to being energy positive[3] but are not yet self sustaining. Large ongoing projects like like…

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. https://www.lockheedmartin.com/en-us/products/compact-fusion...

Re: Google revives controversial cold-fusion experiments

#124
post #46

The cynicism in this threads hurts. > “This is not just a chase for cold fusion,” says Matthew Trevithick, a research programme manager at Google in Mountain View, California. “If it were, I don’t think we would have maintained an interest of this calibre of team for so long.” Here's what I see: fusion power would be a step function in human civilization. Such step functions are pathologically hard to achieve, becaus…

Humanity can already access more energy than is healthy for our planet. Even if you had a zero-greenhouse-gas source of energy, all that energy is eventually dissipated as heat, so it would not be safe to use an unlimited quantity of it.

I looked at the numbers about 10 years ago and iirc I concluded that waste heat is about 10% the impact of greenhouse gasses, so not insignificant. I don't remember how I got that number though, and I could have easily messed something up.

Re: Google revives controversial cold-fusion experiments

#125
post #114

Earlier quoted context omitted.

Yeah. As a non lens wearer sounds pretty comfortable to me. But if you have money I can offer you a non-invasive glucose measurement start-up with peer reviewed publications.

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?

Re: Google revives controversial cold-fusion experiments

#126
post #124
post #46

The cynicism in this threads hurts. > “This is not just a chase for cold fusion,” says Matthew Trevithick, a research programme manager at Google in Mountain View, California. “If it were, I don’t think we would have maintained an interest of this calibre of team for so long.” Here's what I see: fusion power would be a step function in human civilization. Such step functions are pathologically hard to achieve, becaus…

Humanity can already access more energy than is healthy for our planet. Even if you had a zero-greenhouse-gas source of energy, all that energy is eventually dissipated as heat, so it would not be safe to use an unlimited quantity of it. I looked at the numbers about 10 years ago and iirc I concluded that waste heat is about 10% the impact of greenhouse gasses, so not insignificant. I don't remember how I got that nu…

If we had near unlimited energy, we could find a way to trap heat energy and remove it.

Re: Google revives controversial cold-fusion experiments

#127
post #123
post #58

Earlier quoted context omitted.

The skepticism is not about fusion power, it's about cold fusion specifically, as well role of proprietary IP and patents in scientific research. Tokamak[1] (and other magnetic confinement) reactors seem much more promising and have seen slow but non-zero improvements for decades[2]. Some reactors like JT-60 have come close to being energy positive[3] but are not yet self sustaining. Large ongoing projects like like…

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.

Re: Google revives controversial cold-fusion experiments

#128
post #58

Earlier quoted context omitted.

The skepticism is not about fusion power, it's about cold fusion specifically, as well role of proprietary IP and patents in scientific research. Tokamak[1] (and other magnetic confinement) reactors seem much more promising and have seen slow but non-zero improvements for decades[2]. Some reactors like JT-60 have come close to being energy positive[3] but are not yet self sustaining. Large ongoing projects like like…

You could argue that this is exactly the type of research that should be funded by private industry: high-risk, high-reward, and unlikely to get government funding.

High-risk is something that private industry rarely to never does (except on vanity projects). All of the venture capital in Silicon Valley is really chasing medium-risk, not high-risk.

Beyond big tickets like fusion, I would direct you to things like initial drug investigations (almost all done in University labs with government grants), or rocket development (almost all done under government grants). In all of these cases the initial development of things that are unlikely to work out are done on public funds, and once it looks like it is just down to the details (still a big undertaking) then private funding steps in. The pattern here is almost always: socialize costs/risks, privatize gains.

Re: Google revives controversial cold-fusion experiments

#129
post #111

Earlier quoted context omitted.

As a Tesla owner, I have to say that I'm really looking forward to them delivering the Full Self Driving option that I paid for 18 months ago when I bought my car.

A hypothetical: You are driving your car and see that the pickup truck in front of you has an empty cardboard box in it (you can tell its empty by the way its floating around in bed of truck). Suddenly a gust of win picks up the box and it lands directly in front of your car. Its not very big, about 12 inches tall. Do you: (a) Slam on breaks? (b) Roll over it? Now what will the "AI" in your car do? Self-driving cars…

That is a fallacious argument.

If we pick a hypothetical where a human fails and an AI doesn't, does that mean self-driving cars are ready?

Do you think human drivers are faultless drivers?

Is their a fair cost-benefit analysis for not wasting enormous amounts of collective time driving? (Driving is a very unproductive activity).

Re: Google revives controversial cold-fusion experiments

#130
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.

Do you mean a single _fusion_ event?
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