Physicists Discover a Strange New Theoretical Phase of Hydrogen

The existence of a weird new phase of hydrogen in solid form has been discovered by scientists using a computer that can learn a few quantum tricks. Even though it is still purely theoretical for the time being, the discovery might be able to shed some light on how matter behaves, from the smallest scales to the internal workings of the largest planets in the universe.

Under extreme conditions, the shape of the hydrogen molecules in this newly discovered solid hydrogen phase, which was discovered by an international team of researchers, changed from spheres stacked like a pile of oranges to something that more closely resembled eggs.

In order to solidify, hydrogen often needs both extremely high pressures and very low temperatures. The researchers discovered the unique chemical arrangement using a cutting-edge machine learning analysis of this particular phase shift.

According to physicist Scott Jensen of the University of Illinois Urbana-Champaign, "We started with the not-too-ambitious goal of refining the theory of something we know about."

It was more interesting than that, which is unfortunate or perhaps fortunate. This brand-new behavior started to emerge. In reality, it was the predominant behavior at high pressures and temperatures, which prior theories made no mention of.

An upgraded machine learning method was crucial to the research since it could simulate the movements of thousands of atoms rather than just the hundreds that are often used in investigations of quantum phenomena.

The Quantum Monte Carlo (QMC) approach, which the researchers enhanced, essentially employs random sampling and probability theory to figure out how vast groups of atoms are acting collectively, groupings that would be too challenging to analyze in a real experiment.

The outcomes were then confirmed using a second computational approach, which was better equipped to handle more atoms but had lower precision. The fact that the results were consistent shows that the improved QMC approach is operating as anticipated.

According to University of Illinois Urbana-Champaign physicist David Ceperley, "Machine learning turned out to teach us a great deal." Because we could only accommodate a limited number of atoms in our previous simulations, we didn't trust the indications of novel behavior.

We could fully utilize the most precise techniques and determine the true situation thanks to our machine learning model.

To put it simply, the machine learning component increased the precision and range of the simulations the scientists could conduct by leveraging pre-existing data and earlier simulations to improve the estimations from subsequent ones.

In addition to being the most prevalent element in the universe, hydrogen also has the simplest atomic structure, consisting simply of one proton and one electron. The rest of physics can therefore be significantly impacted by new hydrogen-related findings.

It is now too early to determine what this new solid hydrogen phase entails, and further modeling and testing are needed to examine it in greater detail. The study of hydrogen-rich planets like Jupiter and Saturn is simply one use of this additional knowledge, though.

Ceperley asserts, "We should start with systems that we can attack because we want to understand everything. "It's important to know that we can deal with hydrogen because it's straightforward."

The research has been published in Physical Review Letters.