How much do we know about time? Not much, if you think about it. For the thing we value most of all, we’re largely ignorant of what time is and how time works (at least from a physics standpoint). But we’re slowly learning that time is much stranger than we thought, to the point where its oddities have some convinced we’re living in a simulation. And adding to the weirdness, we’ve discovered a new form of matter called ‘time crystals.’
Time crystals are forms of matter that defy basic physics. Think back to what you know about Newton’s third law: For every action there is an equal and opposite reaction. If you lift one end of the ball on a Newton’s cradle and let it go, one ball at the other end will fly up.
With a time crystal, you lift one ball up, let it go, and two balls fly up on the other end. Why? Well, every particle, including those in matter, have something called “spin.” You can reverse the spin of particle, much like you can whack a tetherball away from you. But what happens in time crystals is weird: if you feed those particles even a small amount of energy, they match each other on spin and begin to change spin together, on their own time frame, regardless of the energy fed into the system. As long as you zap them, they’ll move, but they’ll do it their way, thank you, not in the way the energy introduced into the system tells them. In short, with time crystals, for every action, there is not an equal and opposite reaction.
OK, so, weird, but what’s the takeaway? The short answer is that this means there are likely undiscovered forms of matter. One of the experiments that proved these exist discovered that it causes a diamond loaded with impurities to light up like an LED. What we know as solid, liquid, and gas are all states of matter in space. As you introduce heat, the solid crystal of ice melts into a pool of water which dissolves into steam. What this implies is that there’s forms of matter that do the same thing, but in time. Whether there’s any practical application is an open question (we haven’t discovered those forms of matter yet), but they’ll likely have some crazy implications when we do find them.