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Discovery of Time Crystals Could Radically Change Our Understanding of the Space-Time Continuum
Time crystals could even form stable qubits, making quantum computing possible.
Consider a structure that moves not in space but time, crystals that change shape and move perpetually without energy, and always return to their original state. Such a structure would break the second law of thermodynamics, a cardinal rule of physics. Yet, in 2012, Nobel Laurette and theoretical physicist Frank Wilczek imagined them, what he called time crystals. Their movement isn’t of their own accord. Instead, a fracture in time’s symmetry allows for them to stay in perpetual motion.
Why crystals? Because they act atypically compared to other forms of matter. The way they construct themselves, in columns, rows, and lattices, suggests a spherical shape. But they often aren’t round or even symmetrical. Crystals therefore, are the only form of matter which compromises the spatial rule of nature. This states that all areas within space are equal and valid. Crystals break this law by repeating themselves again and again in lattices which form obscure shapes.
Space and time being related, Wilczek wondered if there were crystals who broke the temporal symmetry of nature as well. This rule states that stable objects are constant throughout time (with the exception of entropy of course). Wilczek’s equations proved mathematically that a continuous lattice could theoretically repeat itself in time. But how could something move on and on forever without using energy?
Time crystals move continually due to a “break in the symmetry of time.” These revolve at regular, calculable intervals, illustrated as a lattice continually repeating itself, thus breaking the law of temporal symmetry. Though his equation worked out, Wilczek’s theory was at first dismissed as “impossible,” by colleagues.
Theoretical physicist Frank Wilczek.
A recent paper showed that they might in fact be possible. [Update: They're real—it's official] This emboldened researchers at the University of California, Santa Barbara. Experimental physicists there teamed up with colleagues at Microsoft’s research lab station Q, and outlined how they could prove their existence. Two teams of scientists then followed this “blueprint” and actually made time crystals. The first was out of the University of Maryland in College Park, led by Chris Monroe. The other was at Harvard University, led by Mikhail Lukin.
In the University of Maryland experiment, researchers took 10 ytterbium ions whose electron spins were entangled, and used a laser to create a magnetic field around them. Then a second laser was used to push their atoms. The atoms started moving together, due to their entanglement, creating a pattern of repeating lattices. Besides physical symmetry, the atoms would have to break time symmetry as well. After a few moments, something odd happened. The pattern of movement soon became different than that of the laser pushing the atoms. Atoms reacted even when the laser hadn’t hit them.
Consider a Jell-O mold resting on a plate. If you take a spoon and smacked it, it’ll jiggle. But if it were a time crystal, it would never stop moving, oscillating even at its resting or ground state. But what if the Jell-O reacted, even when you hadn’t tapped it? Odd as it is, that’s what happened in this experiment, according to one physicist.
By using different laser pulses and creating different magnetic fields, scientist found that they could change the phase of the crystals. Harvard researchers conducted a similar experiment. But here, they used the centers of diamonds containing flaws known as nitrogen vacancy centers. These molecules were hit with microwaves and they reacted in the same way. Two separate systems showing the same results proves that this type of matter is indeed present. It also illustrates that breaks in symmetry can occur not only in space but in time.
Whereas normal crystals can be asymmetrical in space, time crystals are asymmetrical in time.
Most of the matter we’ve studied up until this point has been at equilibrium or stable at its resting phase. This newly discovered, non-equilibrium matter could upend everything we know about physics. Other forms may also be out there, waiting for us to discover them. Future discoveries in non-equilibrium matter may help us heal the rift between relativity and quantum mechanics, or even create an entirely new model, more precise than these two. It could also lead to new technology, helping to form for example stabile qubits upon which quantum computing can be built. A system using time crystals could store information even after everything around it had perished. It wouldn’t last forever, but longer than almost anything else.
According to Wilczek, the closest thing we have now to a time crystal is a superconductor. No energy could be taken out of the crystals unless first placed inside. Electrons flow through a superconductor linearly without facing resistance. With a time crystal they’d travel in a loop. Theoretically, time crystals could be used in bizarre, lumpy forms. Current would also fluctuate according to the structure’s phase or movement.
Time crystals, according to Wilczek, would have been born early on in the universe’s existence during its cooling phase. Studying these crystals might offer clues to the origins of the universe and how it evolved. It may even revolutionize our understanding of the space-time continuum. Wilczek said in one talk that discovering time crystals would be like discovering “a new continent.” He added, "A New World, or Antarctica, time will tell."
To learn more about time crystals, click here:
A Mercury-bound spacecraft's noisy flyby of our home planet.
- There is no sound in space, but if there was, this is what it might sound like passing by Earth.
- A spacecraft bound for Mercury recorded data while swinging around our planet, and that data was converted into sound.
- Yes, in space no one can hear you scream, but this is still some chill stuff.
First off, let's be clear what we mean by "hear" here. (Here, here!)
Sound, as we know it, requires air. What our ears capture is actually oscillating waves of fluctuating air pressure. Cilia, fibers in our ears, respond to these fluctuations by firing off corresponding clusters of tones at different pitches to our brains. This is what we perceive as sound.
All of which is to say, sound requires air, and space is notoriously void of that. So, in terms of human-perceivable sound, it's silent out there. Nonetheless, there can be cyclical events in space — such as oscillating values in streams of captured data — that can be mapped to pitches, and thus made audible.
Image source: European Space Agency
The European Space Agency's BepiColombo spacecraft took off from Kourou, French Guyana on October 20, 2019, on its way to Mercury. To reduce its speed for the proper trajectory to Mercury, BepiColombo executed a "gravity-assist flyby," slinging itself around the Earth before leaving home. Over the course of its 34-minute flyby, its two data recorders captured five data sets that Italy's National Institute for Astrophysics (INAF) enhanced and converted into sound waves.
Into and out of Earth's shadow
In April, BepiColombo began its closest approach to Earth, ranging from 256,393 kilometers (159,315 miles) to 129,488 kilometers (80,460 miles) away. The audio above starts as BepiColombo begins to sneak into the Earth's shadow facing away from the sun.
The data was captured by BepiColombo's Italian Spring Accelerometer (ISA) instrument. Says Carmelo Magnafico of the ISA team, "When the spacecraft enters the shadow and the force of the Sun disappears, we can hear a slight vibration. The solar panels, previously flexed by the Sun, then find a new balance. Upon exiting the shadow, we can hear the effect again."
In addition to making for some cool sounds, the phenomenon allowed the ISA team to confirm just how sensitive their instrument is. "This is an extraordinary situation," says Carmelo. "Since we started the cruise, we have only been in direct sunshine, so we did not have the possibility to check effectively whether our instrument is measuring the variations of the force of the sunlight."
When the craft arrives at Mercury, the ISA will be tasked with studying the planets gravity.
The second clip is derived from data captured by BepiColombo's MPO-MAG magnetometer, AKA MERMAG, as the craft traveled through Earth's magnetosphere, the area surrounding the planet that's determined by the its magnetic field.
BepiColombo eventually entered the hellish mangentosheath, the region battered by cosmic plasma from the sun before the craft passed into the relatively peaceful magentopause that marks the transition between the magnetosphere and Earth's own magnetic field.
MERMAG will map Mercury's magnetosphere, as well as the magnetic state of the planet's interior. As a secondary objective, it will assess the interaction of the solar wind, Mercury's magnetic field, and the planet, analyzing the dynamics of the magnetosphere and its interaction with Mercury.
Recording session over, BepiColombo is now slipping through space silently with its arrival at Mercury planned for 2025.
Research suggests that aging affects a brain circuit critical for learning and decision-making.
As people age, they often lose their motivation to learn new things or engage in everyday activities. In a study of mice, MIT neuroscientists have now identified a brain circuit that is critical for maintaining this kind of motivation.
Researchers develop the first objective tool for assessing the onset of cognitive decline through the measurement of white spots in the brain.
- MRI brain scans may show white spots that scientists believe are linked to cognitive decline.
- Experts have had no objective means of counting and measuring these lesions.
- A new tool counts white spots and also cleverly measures their volumes.
White spots and educated guesses<p>The white spots, or "hyperintensities," are brain lesions—fluid-filled holes in the brain believed to have been left behind by the breaking down of blood vessels that had previously provided nourishment to brain cells.</p><p>Prior to the new research, the quantity of white spots was assessed using an imprecise three-point scale indicating ascending likelihoods of dementia: A minimal number of spots was considered as level 1, a medium number of spots level 2, and a great number of them level 3.</p>
How the new measurements were derived<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDYwMTc1OS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNDQ1ODExNX0.vqhQJSvL99KjOe24TOs4E8R7c6-pprbXYSrGcIqbVps/img.jpg?width=980" id="c64d9" class="rm-shortcode" data-rm-shortcode-id="002d9b8ef47b5a86c3a387ad2cd90629" data-rm-shortcode-name="rebelmouse-image" />
Credit: sfam_photo/Shutterstock<p>The team of researchers from NYU's Langone's <a href="https://med.nyu.edu/departments-institutes/neurology/divisions-centers/center-cognitive-neurology" target="_blank">Center for Cognitive Neurology</a> and <a href="https://med.nyu.edu/departments-institutes/neurology/divisions-centers/center-cognitive-neurology/alzheimers-disease-research-center" target="_blank">Alzheimer's Disease Research Center</a> were led by <a href="https://med.nyu.edu/faculty/jingyun-chen" target="_blank">Jingyun "Josh" Chen</a>. They analyzed 72 MRI scans from a national database of older people taken as part of the <a href="http://adni.loni.usc.edu" target="_blank">Alzheimer's Disease Neuroimaging Initiative</a> (ADNI). The scans were mostly of white people over age 70, and there were a roughly equivalent number of men and women. Some had normal brain function, some were presenting moderate cognitive decline, and some had severe dementia.</p><p>Without knowing each individual's diagnosis, the researchers analyzed the white spots in their scans. While the team counted each scan's lesions, the innovation they introduced was the production of a 3D measurement for each lesion's fluid volume. The measurement was derived by measuring a lesion's distance from opposite sides of the brain.</p><p>Measurements of 0 milliliters (mL) were assessed for areas without white spots, with other white spots coming up as containing 60 mL of fluid. Chen's team predicted that volumes over 100 mL could signify severe dementia.</p><p>"Amounts of white matter lesions above the normal range should serve as an early warning sign for patients and physicians," Chen told <a href="https://nyulangone.org/news/white-matter-lesion-mapping-tool-identifies-early-signs-dementia" target="_blank">NYU Langone Health NewsHub</a>.</p><p>When the team compared the likely diagnoses derived from their calculations against the individuals' medical records, they found that their predictions were correct about 7 out of 10 times.</p><p>The researchers compiled their formulas into an online tool that's available to physicians for free via <a href="https://github.com/jingyunc/wmhs" target="_blank" rel="noopener noreferrer">GitHub</a>. The researchers plan to further refine and test it using an additional 1,495 brain scans representing a more diverse group of individuals from the ADNI database.</p>