If it is, I’ll bet all those scientists working in multi-billion dollar facilities trying to make hot fusion work as a power source sure feel dumb.
By the way, are we still ten years away from that, like we’ve been for the last 60 years?
A little bit more than 10, but close:
But even these guys admit this:
Can someone clarify whether cold fusion is laws-of-physics Impossible or how the hell should we know impossible?
For example, faster than light travel is Impossible. Even if you had a stable, science-minded, hyper-intelligent and space-craving society with a million years to work on the problem, FTL travel cannot be.
But there is lots of technology that would have been thought impossible in the recent past, primarily because several generations of technological advances needed to take place before the final product. (This is not to suggest that technology necessarily will overcome hurdles; I’m just trying to distinguish between impossibilities.)
Fusion involves getting two atomic nuclei close enough together that they merge - this is difficult, because although the strong nuclear force makes protons and neutrons attract one another, it only operates at a very short range - at slightly longer ranges, it is overcome by the electric force, which pushes them apart.
So you can do this by squeezing things very hard (as in the sort of pressures in the centre of the sun), or colliding things at very high speed - which is really the same as squeezing them, just on a smaller scale.
I don’t believe we have completely ruled out the possibility of some other way to get nuclei close together - some way that does not require macroscopic violence - in the case of Cold Fusion, I think it was conjectured that some exotic property of the physical shape of certain kinds of matter, combined with an electric current, was somehow contriving to force things together (perhaps by partial cancellation of electric forces or something). Of course, that was all talk, as the experiment was unrepeatable.
IANANuclear Physicist, but I believe I’m right in saying that we don’t know for sure that we know all the ways in which fusion can be made to happen.
That’s because you’re working with ColdFusion, not Cold Fusion. The electrostatic repulsion between the words has been overcome using advanced field-screening techniques.
I thought FTL travel was possible, it’s travel at c that’s impossible?
Yes, I think it’s more accurate to say we cannot accelerate a mass up to a velocity of c in our space. Whether it’s possible to transport something to somewhere outside of its light-cone is another question – if large wormholes are possible, for example, then it’s feasible.
I think it’s mathematically consistent to have particles that travel faster than c and it would take infinite energy to slow them down to c: tachyons.
No evidence of tachyons has been found yet, and making tardyons (like the particles you and I are made of) into tachyons is ruled out.
<pause for actual scientist to slap me down…>
As others have said, not really, and indeed the man-on-the-street doesn’t really get why this is not a practical proposition today.
After all, we had fission bombs, fusion bombs and fission power in quick succession (within 10 years if you count from the first fission bomb to the first working power station).
What’s the biggie with fusion power? Must be a conspiracy!
I have nearly perfected a perpetual motion machine.
That will be much better than cold fusion.
I don’t actually have a working model yet, but if I had more funds…
Irving was a bright scientist.
As discussed above, this falls into your “impossible” category. We know exactly what we’d need to produce cold fusion: some means for bringing two protons into close enough range, so that the strong nuclear force can, on average, overcome the electrostatic repulsion. What we haven’t found is any way to actually do that in a manner that produces more energy than it expends (like with the muon catalysed fusion discussed above). So far, all of the alleged methods of doing this have proven to be wrong, but that doesn’t rule out some new method being discovered.
But it does seem highly unlikely.
Well, the difference between fission and fusion highlights the problem: fission is produced when an uncharged neutron hits a charged nucleus. Since the neutron has no charge, there is no electrostatic barrier to overcome, so it’s merely a matter of having enough neutrons around to ensure a sufficient number of reactions sufficiently frequently to produce useful amounts of energy. We knew early on that the limit with fission was how to produce sufficient neutrons to initiate, and then sustain, the fission reaction. Once we solved that, it all came together.
As for fusion bombs, well that’s just the regular hot fusion we’ve known about for years, just in a somewhat uncontrollable state.
Currently, a practical (hot) fusion power plant is about forty years away, if the funding situation remains stable for all that time. It probably won’t, in which case the timeline gets pushed back yet further.
Controlled fusion on a scale too small to be practical is not forty years away, and in fact has been achievable for about fifty years, using equipment you could find or build in nearly any university physics department.
ITER’s proposed date of 2027 for D-T fusion in their equipment isn’t particularly relevant: It’s one of the milestones on the current most likely road towards the 40-year figure, but it’s not itself a practical result.
How can *any *meaningful timeline be assigned to this goal? Certainly none of the many that have run out were meaningful. Some short number of years because the path between current tech and what’s needed is seen and understood, maybe… but when you push it out to a lifetime, or most of one, I think it has to smell strongly of ass.
IIRC, one of the obvious counter-arguments to cold fusion was the lack of detectable neutrons. Fusion of two deuterium atoms to He3 (the expected fusion reaction) should throw off a hih-energy neutron. (a) this has not been observed, except claimed in a few (and yet again) unreproducible experiments. (b) any reaction producing the claimed heat outputs should be producing dangerous levels of neutron output.
Unless your theory of cold fusion involves rewriting nuclear physics at a fundamental level, the evidence is still not there.
As I understood it, the P&F technique involved squeezing H atoms (actually D) inside a metal crystal lattice until the concentration became so dense the occasional collisions did in fact create fusion reactions - a bt of a leap. Where P&F wandered into crazy was when they refused to provide the details on how to process the palladium electrodes to achieve the consistent result they claimed. (I’m assuming they tried to make the crystalline lattice as flawless as possible). Claiming “special process knowledge” and hiding it was a typical ploy of other examples of junk / conspiract theory science.
I’m surprised there’s been no mention of Rossi and e-cat (google to find news of scientists testing in 2013 and more scheduled in 2014).
The Cherokee group just started a new company Industrial Heating and bought the rights to e-cat.
They say they will have initial products in 2nd half of 2014.
I guess we’ll find out pretty quickly if it’s real.
Well, most high schoolers underestimate how far they can go with the education they have. They have the fundamentals but they don’t know how to use those tools to go further.
I’ll just follow Carl’s instructions here. We start with Coulomb’s Law:
F = keq1q2/r^2
ke is Coulomb’s constant and equal to 8.99e9 Nm^2/C^2. q1 and q2 are the charges, which are equal to 1.60217657e-19 C each (one proton, and also just a constant to look up).
But we need energy, and energy is the integral of force over distance. Calculus is high-level high school math, but this is a very simple case. We want to integrate from the width of a helium nucleus to infinity to get the necessary energy. I’ll estimate the width as 1.5e-15 m.
F = keq1q2/r^2
E = integral(kq1q2/r^2, width, infinity)
E = keq1q2integral(r^-2, width, infinity)
E = keq1q2(-1/infinity - -1/width)
E = keq1q2*1/width
Plug in our constants and we get:
E = 8.99e9 Nm^2/C^2 * 1.60217657e-19 C * 1.60217657e-19 C / 1.5e-15 m = 1.538e-13 Nm = 1.538e-13 J
Now for the other part. We compare to the value we get from E=kT. k is Boltzmann’s constant, or 1.3806488e-23 (m^2-kg)/(s^2-K). T is room temperature, since we’re talking cold fusion, or 300 K. Multiply to get:
E = kT = 4.142e-21 J
So the energy scales are off by 8 orders of magnitude! It’s just not even close. That’s why fusion only works at many millions of degrees (to bring that kT value more in line with the electrostatic repulsion).
That’s the one PopSci keeps featuring. They say he’s unpredictable and keeps canceling interviews.
Eh, Popular Science is a car magazine. I’m not sure why anyone would pay any attention to them on other matters.
As others have said, we do not know it is impossible. What we need is a catalyst, something to lower the enormous energy barrier, something that wants to bind deuterons and spit out an alpha particle after eating two of them.
For example, some have speculated about the existence of stable nuclear matter way, way above the mass of the known chemical elements. (I am not talking about neutron stars.) If this were possible, with low enough positive charge, perhaps it could catalyze fusion. Other’s have speculated about stable matter involving strange quarks or other heavy quarks. Perhaps all of these speculations have now been eliminated theoretically, but there are still the ideas we haven’t thought of yet.
Also, muon catalyzed fusion, as mentioned above, has been demonstrated. The problem is to get one muon to catalyze enough fusion events to pay for the energy it took to make the muon. I’m not aware that it has been shown conclusively that this is impossible.
If I may be so bold, I’d like to reformat Dr. Strangelove’s contribution a little for readability. I haven’t altered any of the formulas (at least not intentionally):
Well, most high schoolers underestimate how far they can go with the education they have. They have the fundamentals but they don’t know how to use those tools to go further.
I’ll just follow Carl’s instructions here. We start with Coulomb’s Law:
F = k[sub]e[/sub]q[sub]1[/sub]q[sub]2[/sub]/r[sup]2[/sup]
k[sub]e[/sub] is Coulomb’s constant and equal to 8.99 x 10[sup]9[/sup] Nm[sup]2[/sup]/C[sup]2[/sup]. q[sub]1[/sub] and q[sub]2[/sub] are the charges, which are equal to 1.60217657 x 10[sup]-19[/sup] C each (one proton, and also just a constant to look up).
But we need energy, and energy is the integral of force over distance. Calculus is high-level high school math, but this is a very simple case. We want to integrate from the width of a helium nucleus to infinity to get the necessary energy. I’ll estimate the width (w) as 1.5 x 10[sup]-15[/sup] m.
F = k[sub]e[/sub]q[sub]1[/sub]q[sub]2[/sub]/r[sup]2[/sup]
E = ∫[sub]w[/sub][sup]∞[/sup] (k[sub]e[/sub]q[sub]1[/sub]q[sub]2[/sub]/r[sup]2[/sup])
E = k[sub]e[/sub]q[sub]1[/sub]q[sub]2[/sub]∫[sub]w[/sub][sup]∞[/sup] (r[sup]-2[/sup])
E = k[sub]e[/sub]q[sub]1[/sub]q[sub]2[/sub](-1/∞ - -1/w)
E = k[sub]e[/sub]q[sub]1[/sub]q[sub]2/sub
Plug in our constants and we get:
E = 8.99 x 10[sup]9[/sup] Nm[sup]2[/sup]/C[sup]2[/sup] * 1.60217657 x 10[sup]-19[/sup] C * 1.60217657 x 10[sup]-19[/sup] C / 1.5 x 10[sup]-15[/sup] m = 1.538 x 10[sup]-13[/sup] Nm = 1.538 x 10[sup]-13[/sup] J
Now for the other part. We compare to the value we get from E=kT. k is Boltzmann’s constant, or 1.3806488 x 10[sup]-23[/sup] (m[sup]2[/sup]-kg)/(s[sup]2[/sup]-K). T is room temperature, since we’re talking cold fusion, or 300 K. Multiply to get:
E = kT = 4.142 x 10[sup]-21[/sup] J
So the energy scales are off by 8 orders of magnitude! It’s just not even close. That’s why fusion only works at many millions of degrees (to bring that kT value more in line with the electrostatic repulsion).