Future/near Future technologies

[Az]

ermm, so what exactly happens in a Hydrogen bomb, not a H+H reaction?

[Dauphin]

H bombs don't ignite the atmosphere, depsite it being replete with hydrogen. (although it was a major fear in the 50s)

[Az]

Why?

I think it's because:
1) The atmosphere is much less dense.
2)It's composed of Nitrogen and oxygen, that are waay harder to fuse.

But if we put a probe that would sink, a couple of hundreds of feet deep into Jupiter, there will be tons of Helium, and Hydrogen.


I know that my question sounds far-fetched, esp. with the Shumacher-Levy comet that was said to generate much more energy than any nuke.

[KrazyHorse]

Azazael, the heat would be dispersed faster than it was created.

If not, as BC has said, Jupiter would have gone critical already. There is fusion going on all the time wherever there's hydrogen...but without sufficient density of hydrogen it dies out.

[Dauphin]

Jupiter is more dense, but I doubt dense enough to sustain a nuclear reaction.

When they discuss minimum solar masses I don't think that its ignition that is the issue, more the sustainability of a reaction due to high temperature and density. Jupiter would lose heat through radiative transfer too quickly to retain the necessary temperature, and its density would fall due to the higher temperature causing expansion.

[KrazyHorse]

Exactly. With sufficient density, a trigger will always be found. Either a cosmic ray or just statistical variations in the energy of each individual particle will end up generating a single reaction...and if you're at critical density, that'll ignite another, etc.

[Dauphin]

Originally posted by Azazel
ermm, so what exactly happens in a Hydrogen bomb, not a H+H reaction?

D-T, I would imagine.

[Az]

but I am not talking about an incidental existance of an activation energy. that would release this couple of MeV. I am talking about a nuke that would trigger fusion on a scale, just like in an H-bomb.

If you could please explain me why it isn't feasible?

The energy of a nuke, just dissipates?

[NeOmega]

So what makes a quantum computer more desirable than a binary computer?

[KrazyHorse]

Nothing. It's basically an analogue computer. People point to the mass amounts of information storage, but neglect to tell you that it's fault-prone just like every other analogue storage method.

[Az]

hmm, crosspost with Frogger:

so there is no way to make Jupiter ignite?

[KrazyHorse]

Originally posted by Azazel
but I am not talking about an incidental existance of an activation energy. that would release this couple of MeV. I am talking about a nuke that would trigger fusion on a scale, just like in an H-bomb.

If you could please explain me why it isn't feasible?

The energy of a nuke, just dissipates?

Azazel, it doesn't matter how much energy you pour in. You'll never get a self-sustaining reaction. If you put enough energy in (billions of H-bombs?) then the atmosphere would fuse completely...but it wouldn't have been a self sustaining reaction.

It's just like fission reactions. If I only have a gram of uranium I can't make it undergo a self-sustaining chain reaction. I can bombard it with neutrons until it's all transmuted, but at any point if I stop bombarding it the reaction will just die down.

[KrazyHorse]

Originally posted by Azazel
hmm, crosspost with Frogger:

so there is no way to make Jupiter ignite?

Maybe if you had 10 or 20 jupiters and banged them into each other...or if you had some sort of nuclear catalyst that would drop the activation energy of the H-H reaction (I'm not aware of any such energy path).

[Az]

ok...a last one: how did the sun ignite, then?

[KrazyHorse]

It had enough mass to provide a sufficiently dense environment. The original "spark" would be impossible to determine. It could have been anything that momentarily raised a very, very small region of the sun to a high enough temperature. Random fluctuations in molecule speeds would have done it pretty quickly, but something else may have done it first. It probably "lit" millions of times and was then "extinguished" because it didn't yet have enough mass (it hadn't sucked up enough of the primordial hydrogen from surrounding regions yet).