Nutcracker fusion

[Bengey]

Would it be possible to mechanically trap deuterium and tritum atoms and squeeze them together in a nutcracker type device to fuse them? I believe we have technology to manipulate individual atoms, or at least small quantities, and it should be possible to get them into a vise. This would avoid the high energies and temperatures of other approaches.

 

[rootone]

Well what you are looking for here is device capable of generating such a high pressure and density that the atoms spontaneously fuse.
Such systems are not only possible, they actually exist, but they are hardly 'low energy'.
They are called stars.

 

[Bengey]

Well what you are looking for here is device capable of generating such a high pressure and density that the atoms spontaneously fuse.
Such systems are not only possible, they actually exist, but they are hardly 'low energy'.
They are called stars.

No, I'm looking for a device to mechanically overcome the Coulomb force for just a few atoms at a time, avoiding high temp and pressure. I believe the energy needed is on the order of .1MeV

 

[mathman]

The problem is confining the force needed to a small area. Laser fusion program is vaguely similar to what you want.

 

[Bengey]

What I'm asking is whether some kind of mechanical confinement can achieve the goal. We've made great advances in nanotechnology, why not nano-nutcrackers to squeeze atoms together? As for laser fusion, wouldn't that also be easier to achieve with micro or nano-sized fuel pellets?

 

[Hornbein]

What I'm asking is whether some kind of mechanical confinement can achieve the goal. We've made great advances in nanotechnology, why not nano-nutcrackers to squeeze atoms together? As for laser fusion, wouldn't that also be easier to achieve with micro or nano-sized fuel pellets?

There are diamond anvils that create great pressures. But not nearly enough for fusion. It seems to me that almost any material would shatter before it would cause hydrogen to fuse.

Right now they are trying to produce liquid metallic hydrogen with diamond anvils, but the diamonds shatter. It seems to me that the hydrogen is going to diffuse into any conceivable material before it will fuse with itself.

 

[Bengey]

Would the first problem go away if you're dealing with very small amounts? If I'm right about needing only on the order of .1MeV, that doesn't seem diamond-shattering. On the other hand the diffusion issue seems more serious. Or would a speedy operation get around that?

 

[mathman]

What I'm asking is whether some kind of mechanical confinement can achieve the goal. We've made great advances in nanotechnology, why not nano-nutcrackers to squeeze atoms together? As for laser fusion, wouldn't that also be easier to achieve with micro or nano-sized fuel pellets?

Pellets are small. ~.1 mm diameter in at least one program.

 

[Bengey]

Which program, and do you know if that's giving them better results?

 

[mathman]

Which program, and do you know if that's giving them better results?

The only specific size I found was for an older program (Shiva). Google "laser fusion pellet" gives lots of hits, but it is hard to find numbers for the size.

 

[mheslep]

No, I'm looking for a device to mechanically overcome the Coulomb force for just a few atoms at a time, avoiding high temp and pressure. I believe the energy needed is on the order of .1MeV

Yes that's the ballpark, fusion occurs as low as ~0.01 MeV for the ions of deuterium and tritium fuel. One way to look at the problem with using a mechanical "nutcracker" is that the chemical bonds holding together solid lattices are on order of a couple eV, tens of thousands times less: a bit like trying slam two cannon balls together with cotton candy. That's of course as one would expect, else fusion would be ongoing all the time inside the Earth where pressures are extreme, but far short of that which can be found inside of a star.

 

[e.bar.goum]

a bit like trying slam two cannon balls together with cotton candy

I'm going to have to remember that analogy, it's just a bit brilliant.