Simulation model for molecular hydrogen under high pressure

March 24, 2014

Some experiments are really difficult to perform in practice. To gain a detailed understanding of the behaviour of molecular hydrogen (H2), for example, we would have to produce such high pressures as those occurring within the core of gaseous planets like Jupiter and Saturn or inside stars. If such conditions cannot be created, an alternative method is to simulate them on the computer, but the model has to be accurate. A group of research scientists from the International School for Advanced Studies (SISSA) in Trieste used a simulation model that is far more accurate than previously used, and carried out an experiment to test a hypothesis about the behaviour of hydrogen that is splitting the scientific community.

"We developed this simulation method here at SISSA over the past ten years", explains Sandro Sorella, a SISSA professor and co-author of the paper. "It's a highly accurate technique based on the quantum Monte Carlo method – a family of algorithms but usually limited to a small number of particles – that we have developed in order to consider now a large number of atoms, and obtain an almost realistic situation. A great advantage".

"We used the simulation to verify the Wigner and Huntington prediction", adds Guglielmo Mazzola, from SISSA and first author of the paper.

In 1935 Eugene Wigner and Hillard Bell Huntington conjectured that at very high pressures, when makes the transition from the "molecular" phase to the "atomic" phase (when the atoms are so close to each other that the molecular structures can no longer be distinguished), hydrogen acquires metallic properties.

"In recent years, attempts to verify this hypothesis both theoretically and experimentally have yielded conflicting results with regard to the pressure required to achieve 'metallization'", comments Mazzola. "Our simulation, in the , showed that we might indeed be very far from being able to observe this transition experimentally. According to our findings, metallization can only take place at pressures approaching 500 gigapascal. This is an enormous value, which only occurs in the innermost layers of gaseous planets and cannot be achieved with currently available experimental equipment".

"A detailed understanding of the of hydrogen", concludes Sorella, "is not only important for studies in the field of astrophysics, but also for learning how this element behaves and, for example, under what conditions it becomes a superconductor".

The research was conducted in collaboration with the advanced research institute AICS-Riken in Tokyo, which provided the computational resources of one of the most powerful supercomputers in the world, the K-computer.

Explore further: Study of liquid hydrogen provides important data for planetary models

More information: Guglielmo Mazzola, Seiji Yunoki & Sandro Sorella. "Unexpectedly high pressure for molecular dissociation in liquid hydrogen by electronic simulation." Nature Communications 5, Article number: 3487 DOI: 10.1038/ncomms4487

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no fate
1 / 5 (1) Mar 28, 2014
Why must they assume that somehow a dense form of Hydrogen has made it's way to the center of a gas giant planet? It is the lightest element and is abundant at the top of every atmosphere including the sun.
This is the only place where there is unbound Hydrogen in it's elemental form (in a plantary system). What is the proposed sorting mechanism that allowed hydrogen to defy the physical laws regarding atomic mass/elemental sorting at any point during planetary formation?

A layer of molecular hydrogen beneath ANY other element defies the laws of physics.
Steve 200mph Cruiz
not rated yet Apr 04, 2014
No fate, beyond the fact that it doesn't really matter what other layers are made of when you're over 80% hydrogen and helium.
The important thing about this is that ultra high density hydrogen procures metallic properties, which means electrons can easily flow through it.
Experimental observation of this phenomenon in gas giants? Jupiter's magnetic field is so powerful, it would appear 4 times the size of the full moon here on earth. Now give me one material that could give Jupiter it's measured mass as well as well as being even more conductive than iron and is abundant.
no fate
1 / 5 (1) Apr 14, 2014
Steve: Go play with Hydrogen and try to mesh the proposed temperature and density that current models claim are physically possible. In other words, try to mesh the math with reality....Good luck.

Secondly, this statement :"The important thing about this is that ultra high density hydrogen procures metallic properties, which means electrons can easily flow through it."cannot be made until you can actually show it to be true. That is the theory of how metallic hydrogen "should" behave if and when it is found to exist.

Lastly, explain how we measured Jupiters mass please...I know how we have calculated what we believe it to be...i didn't realize we had measured it.
not rated yet Apr 15, 2014
There is some subtle but quite old evidence, that the hydrogen forms an unstable amalgam with mercury in similar way, like the sodium or another alkali metals. Such a findings could open the route for studying of metalic hydrogen at lower pressures.
no fate
1 / 5 (1) Apr 15, 2014
Zeph. The problem with the proposed theory of metallic hydrogen's existence is it's ionization temperature. It is a plasma long before it can reach a metallic state, at which point it is more influenced by a magnetic field than by gravity. Nature doesn't allow the suspension of the laws of physics that govern it....even if the math tells her to.

Apr 15, 2014
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Apr 15, 2014
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Captain Stumpy
3 / 5 (2) Apr 15, 2014
Many cold fusion catalysts belong into this category too

citation needed
Apr 15, 2014
This comment has been removed by a moderator.
Captain Stumpy
3 / 5 (2) Apr 16, 2014
Einstein realized it in 1947 already
No peer reviewed article/study/paper? you've only provided a couple of articles which support your belief system, neither of which support the question I asked.
Where is the links/proof supporting your conjecture that
Many cold fusion catalysts belong into this category too
Any period articles scanned or perhaps a paper published?

better yet, given your knowledge, how about giving us a working prototype?
you may be interested about his a ether model too
Apr 16, 2014
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no fate
3 / 5 (2) Apr 16, 2014
Zeph, nature does have her tricks. Kanzius isn't only freeing hydrogen, the flame would be transparent, his demonstration required salt water because the sodium ions are required for the RF/heat interaction to propegate. But a cool video none the less.

If cold fusion becomes a functional reality I would imagine you will be hosting quite the victory party. But as Stump points out, we have nothing tangible as a result of theory...although JET's NANOR @ MIT seems to be raising some eyebrows...It will be interesting to see how long the system continues to function.

Kinda had a chuckle at the astroblaster theory, if it were accurate it would make any lobed structure physically impossible in a planetary nebula. There is alot more going than a simple compression bounce.

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