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Comment by mikeq101101 | Hacker News Reader

Can someone explain what are some consequences and real world applications of this?

The applications lie not in the magnetic field directly, but its usage in research, allowing us to develop better technologies. By knowing how a material or structure behaves in such gigantic fields, we develop a better understanding of it, which then gets applied in the real world.

Mikhail Erements at Max Planck is using diamond anvils to crush hydrogen at 495GPa to obtain a theoretically predicted room temperature superconducting metallic hydrogen solid. The pressure generated by this electromagnetic implosion experiment is of the same order of magnitude. Plasma inserted in a liquid metal cylinder which undergoes EMFC has been talked about as a potential fusion generator since the 1950s with little experimental success, due to engineering limitations.

What is the reason why can't you use a magnet directly to crush charged hydrogen particles? or lasers for that matter?

Because there is no way to build a machine to generate continuously very strong magnetic fields (the limit is just below 40T iirc, by room temperature, Bitter Electromagnets). This is magnitudes lower than a 1200T pulse in that article. 40T is barely enough to lift up a small animal and keep it suspended in the air, because of the blood iron and water. How would you continuously crush hydrogen with that? The magnetic flux is way to weak on the atomic scale.

One could argue, why not use superconducting electromagnets (used in fusion machines), but surprisingly the limit is lower there, something above 20T!

So, pulses are much stronger, but also very short. Continuously strong fields need insane machinery which might have thermodynamic limits of what is possible to achieve.

Thanks for your answer. I'm really curious how practical metallic hydrogen it.

>How would you continuously crush hydrogen with that?

Why do you the crush to be continuous? I thought the idea of metallic hydrogen was that it is stable once you get it in a metallic state.

Applying continuous pressure on solid hydrogen is equivalent to keeping the ice cool to prevent melting. On earth, I suppose, solid hydrogen would melt, boil and slowly evaporate without external pressure, if not furiously explode when mixing with oxygen. The better questions are, does it take less pressure to keep hydrogen solid than continuously and literally crushing it? Besides that, how do you keep solid hydrogen under pressure from all directions at once?

metallic hydrogen is believed to be metastable, predicted to remain a solid down to 20-40GPa (60-120T).

there are two main hypothetical uses for it: a solid rocket fuel (with a x4 increase in specific impulse) and a superconducting wire with zero transmission loss across long distances (making solar farms in remote places attractive). there may also be military applications eg. hypersonic thermobaric weapon delivery systems.

the other replies in this thread are more realistic. the experiment is likely to study what happens to atoms in high magnetic fields, electrons for example start to pool together in strange ways. as with most scientific research, useful applications are often beyond the horizon and emerge from serendipitous discovery.

There certainly are consequences concerning science and research of electromagnetic fields and radiation, fusion power research and application.

Direct real world applications? There are none, really. Where would you need 1000 T which basically makes everything metallic evaporate in it's vicinity?

> Where would you need 1000 T which basically makes everything metallic evaporate in it's vicinity?

There are lots of metallic big things on different types of battlefields, like tanks or even aircraft carriers, it would be really helpful for the opposing sides to be able to “evaporate” them. Not sure how close to implementing this as a weapon we are, though, probably not that much.

I see, my imagination is lacking weaponry.

> There are lots of metallic big things on different types of battlefields, like tanks or even aircraft carriers, it would be really helpful for the opposing sides to be able to “evaporate” them. Not sure how close to implementing this as a weapon we are, though, probably not that much.

70 years ago

When I read the first article about his some days ago, the authors of the experiment were happy with the result, and said it is useful for fusion power.

Seemly some fusion power reactor designs DO need a temporary very strong magnetic field.

> Where would you need 1000 T which basically makes everything metallic evaporate in it's vicinity?

Hmm, does that mean it would evaporate a Faraday cage?

It depends on dimensions of the cage, of course, and in case the cage is not grounded the resulting inductive eddy currents could easily melt/ blow up the cage. Provided the magnetic flux is strong enough the cage also could easily be evaporated/desintegrated. See the Z-Pinch project of Sandia Labs where a tiny tungsten cage was evaporated in femtoseconds iirc. https://www.sandia.gov/z-machine/

Rail gun.

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