Harvard scientists shook the world after they officially published their success in creating an entirely new material which may not exist anywhere else in the universe: Metallic hydrogen. The findings were recently published in the journal of Science.
[Image Source: Harvard]
It was last October when Harvard University physicist Isaac Silvera created quite a stir after he invited a few colleges to witness something they have never seen before: Metallic hydrogen. The word quickly spread, soon enough, hundreds of people lined up to take a glimpse into a microscope to see a reddish silver dot trapped between two diamond tips.
The findings, if validated, could be the greatest discovery in science- ever.
“If it’s true it would be fantastic,” says Reinhard Boehler, a physicist at the Carnegie Institution for Science in Washington, D.C. “This is something we as a community have been pushing to see for decades.”
Why does it matter?
Creating solid metallic hydrogen could very well revolutionize science as we know it. Metallic hydrogen is thought to be a room temperature superconductor. At the moment, no other room temperature superconductors exist, making the applications practically endless.
A room temperature superconductor could create new wires, which do not lose power during transmission, saving hundreds of millions a year. Furthermore, immensely powerful magnets could be made to enable MRIs to operate at room temperature making them easier and cheaper to maintain and produce.
In addition, the same powerful magnets, which could be used in MRIs, could also be used to create critically dense plasma and open up the world of fusion power- potentially at room temperature.
Perhaps the most astonishing are the potential applications in interplanetary travel.
“People at NASA or the Air Force have told me that if they could get an increase from 450 seconds [of specific impulse] to 500 seconds, that would have a huge impact on rocketry,” Isaac Silvera, the Thomas D. Cabot Professor of the Natural Sciences at Harvard University, told Inverse. “If you can trigger metallic hydrogen to recover to the molecular phase, [the energy release] calculated for that is 1700 seconds.”
Metallic hydrogen is also proposed to be “metastable”- meaning if the material is compressed to a very pressure and is then released, it will remain at that pressure. The properties are similar to that of carbon- compress it enough and a diamond will form, releasing the pressure will not cause the diamond to change back. Although, once heated, a diamond will revert into graphite.
The method for creating metallic hydrogen has been postulated since it was first proposed in 1935 by Eugene Wigner and Hillard Bell Huntingdon. The idea was that under immense pressures, a molecular hydrogen lattice will break down and allow electrons to flow free from one molecule to the next. The scientists modestly proposed that creating pressures of 25GPa would satisfy the conditions for solid metallic hydrogen to be created.
Of course, the number was grossly underestimated. Decades later and with pressures over 10 times more than 25GPa, the mystical metallic hydrogen was nowhere to be seen.
So how did Harvard do it?
High-pressure hydrogen experiments are impeccably difficult to conduct. However, Harvard scientists combated the issue by placing a thin metal gasket between two flat-tipped diamonds. The gasket holds the hydrogen in place as the diamond tips are cranked together at pressures exceeding that of the center of the Earth. Under the intense pressures, the hydrogen can force defects onto the surface of the diamonds. The damaged diamonds become brittle, creating the potential for cracks to form. To combat the issue, scientists add a transparent protective coating to the diamonds.
Under the intense pressures, the hydrogen can force defects onto the surface of the diamonds. The damaged diamonds become brittle, creating the potential for cracks to form. To combat the issue, scientists add a transparent protective coating to the diamonds.
The addition of another material may be skewing the findings, researchers say.
Harvard faces heavy scrutiny
Of course, not everyone is convinced by the claims. As it should be, extraordinary claims require extraordinary evidence.
The additional coatings make laser measurements increasingly difficult to precisely determine what is happening in the center. Unfortunately, it is not the only flaw in the experiment.
Placing hydrogen under pressures exceeding 400 gigapascals (GPa)(nearly 4 million times atmospheric pressure!) causes the hydrogen to turn black, further obstructing a lasers ability to penetrate the material.
“From our point of view it’s not convincing,” says Mikhail Eremets, who currently studies solid metallic hydrogen at the Max Planck Institute for Chemistry in Mainz, Germany.
So has solid metallic hydrogen been created?
At the moment, it is difficult to say. While the heavy scrutiny Harvard is falling subject to may seem damaging, it is there only to further advance science. The data must be analyzed, re-analyzed, and created again before the experiment can be confirmed or dismissed. Despite any accusations of false findings, Harvard scientists remain hopeful in their findings.
Further updates coming soon.