Regular crystals have long intrigued but also confused scientists.
They form naturally repeating, perfect patterns of atoms, and are sometimes described as spontaneous
symmetry breaking through space. Perhaps, then, when we’re not so concerned with the
deepest and most fundamental aspects of reality, crystals are simply nice to look
at… but dedicated crystallography is also a fast-growing academic field. There is,
it seems, so much we can learn from crystals… and particularly when we take them beyond the three
dimensions of space and into a fourth; time. This is Unveiled, and today we’re answering the
extraordinary question; Did scientists just create the first working link between time crystals?
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In the modern age, physicists broadly have two totally different sets of rules for how
the universe works. For any large enough object, classical mechanics will dictate how and where it
can move. From paperclips to tennis balls, cars, airplanes, planets, stars, and even
whole galaxies, they all adhere to the laws of motion that classical mechanics describes. And,
over the years, these by-now-familiar rules have provided us with all the information and knowledge
needed to do anything from building roller coasters… to landing astronauts on the moon.
But, in more recent times, we’ve come to understand that classical mechanics doesn’t
really apply when we zoom in on reality very, very closely. At this, the subatomic level,
it’s quantum mechanics that reigns. And here, things can get quite strange, quite quickly.
Quantum objects can be in two states at once, for example, they can have unpredictable movements,
and they can in general appear to defy the laws of classical mechanics completely.
But where does one system end and the other begin? Merging these two sets of laws remains one of the
biggest problems in physics. How quantum mechanics transforms into classical mechanics at certain
sizes or points is unknown. However, there are objects which might connect these two worlds
in some way… and they’re called time crystals. “Time crystal” is the name given to the phenomenon
of particles periodically recurring not just in space, but also in time. Regular crystals on earth
can be called “space” crystals, by contrast, and they’re something we’ve all seen before.
Diamonds, table salt, and even snowflakes are all examples of “space” crystals… which are
defined by the structure of their atoms repeating in a pattern through space. While we can say that
regular crystals follow the rules of classical mechanics, however, time crystals have to do with
quantum mechanics. A time crystal is a system of particles that acts in harmony and repeats
the same pattern or action in time as well as in space. In this way, time crystals are both stable
and always changing… and so are often thought of as demonstrating a new phase of matter.
To some degree, time crystals have also been labeled a perpetual motion device…
which is a problem to begin with, for classical physics. Perpetual motion devices are impossible
in classical mechanics because energy is always lost in some form, and so a repeated action
cannot go on forever. But time crystals show that that’s not the case in quantum mechanics.
It’s as though the symmetry of a time crystal breaks through time, creating a kind of pocket
where a repeated pattern or action can exist forever, with no energy required. When time
crystals were first theorized in 2012, by the US physicist Frank Wilczek, they were (perhaps
unsurprisingly) thought by many to be impossible structures, as well… but it was only a few further
years until that belief was quashed, with time crystals being built in labs from 2016 onwards.
Now, though, science has moved on again. In a new experiment run this year, in 2022,
scientists were not only able to form two different time crystals, but they successfully
linked them – another breakthrough achievement. Now, not only do time crystals exist, and not
only do we know how to produce them for ourselves, but we can also pair them up and make connections…
on our way, seemingly, to building whole crystal systems. Straight away, the new findings open the
possibility for future technology like fully functioning quantum computers.
A multi-authored paper for the study was published in June 2022, in the journal
“Nature Communications”, and titled; “Nonlinear two-level dynamics of quantum time crystals”. Lead
researcher, Lancaster University’s Samuli Autti, and his team used the helium isotope, helium-3,
to create their crystals. The helium-3 particles were cooled to the extreme and brought down to
their lowest energy state – a base requirement for time crystals – at which point a sort of pulse is
generated from within them, creating periodic waves of magnetic energy called magnons. It’s
these magnons which then fall into time crystal behavior… as their pulsing repeats, in theory
endlessly, without any energy use or loss. The phenomenon goes back to a basic rule of quantum
mechanics which states that objects can never be completely still… so the time crystal essentially
lands into a looping pattern to infinitely produce magnon waves with no energy cost.
Up until this point, the time crystals that had been made – across various studies and experiments
all over the world – were isolated examples. It’s thought, however, that the 2022 study
is the first to put two of them together. With multiple crystals generated, the experimenters
reportedly found that they synchronized and acted as one, despite still being two separate bodies.
In one sense, all the efficiency of a standard time crystal had now been doubled up.
The researchers managed to keep their subjects paired for about 1,000 seconds in total,
or almost 17 minutes, before they collapsed. In that time, the crystals had produced billions
of magnons as they manifested a recurring pattern that could soon become a crucial
component in our future lives. It’s as though, during those 17 minutes, an energy-generating
cavity had been opened up in both time and space. In the old days, we might’ve called it a glitch
in reality… only now, we’re fully in control. But finally, let’s return to why this research
is so important… and why it’s generated such excitement among those in the field. For one,
again, time crystals can potentially act as a bridge between classical and quantum mechanics.
Further research into them – into their abilities and properties – could allow us to better
understand the relationship between these two fundamental systems of physics. Right now, there’s
a classical-quantum disconnect, but time crystals may one day link it all together. Perhaps more
imminently exciting, however, is the potential impact that this work will have on quantum
computing technology. Quantum computers require something called “qubits” to work, or quantum
bits, which are represented as neither binary 1 nor 0 like traditional bits, but can be both at
the same time. Time crystals, then, could be our greatest and most logical route toward qubits…
and by linking them, this latest study has hinted at how these crystals could one day form the base
for ultra-efficient and powerful computing. Elsewhere, further research has also reportedly
shown that time crystals can be made to function in room temperature conditions – or, at least,
that there is a greater possibility for this in the future. In the immediate aftermath of
their discovery, the future for time crystals had still seemed uncertain… largely due to an
apparent requirement for ultra-low temperatures to maintain them. But, in more recent times,
these concerns have lessened, meaning time crystals – and quantum computers – are now being
pitched as possible and operable in a variety of environments. In general, it’s said that a
quantum computer would have the computing power of billions of standard machines. And those working
at the world’s leading tech companies – including Google – have already shown in recent years that
quantum computers can complete extremely advanced equations with seeming ease. Equations that would
take a traditional computer years to work out are now being solved in seconds. But,
with the emergence of linked time crystals, those ridiculous speeds could soon get even quicker!
It's enough to make your head spin, isn’t it? We see the world in one way, but there are quantum
drivers beneath it all… and between these two planes yet more strangeness is possible.
Although perpetual motion machines still can’t exist in classical mechanics, it appears that they
can work just fine as per quantum rules. It’s why, for some, time crystals are now breaking out as
the single most important scientific development of our time. They work in a new phase of matter;
they’ve turned the previously impossible into the seemingly very possible; and they could
soon revolutionize the digital (and, by extension, physical) world. And now, they’re not even working
on their own, in isolation. We’re teaming them up together, and the results could be incredible.
Because that’s how scientists just created the first working link between time crystals.
What do you think? Is there anything we missed? Let us know in the comments, check out these other
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