If you follow science news regularly, you’ve probably heard of the so-called “invisibility cloak” scientists have been working on. That technology is built on the principle of bending waves of visible light so that it wraps around an object rather than bouncing off it, thus rendering it invisible to the naked eye. Though still a long way from giving us actual, portable cloaks of invisibility, it’s still pretty amazing, and now the research has uncovered an even more mind-bending application: creating a “hole in time.”
Anyone who’s grown up on a steady diet of science fiction television can take a deep breath and calm down: we aren’t on the threshold of collapsing the space-time continuum. Instead, as National Geographic reports, the “time hole” involves applying the same principles used in the invisibility experiments – bending or diverting the path of light – to create a gap. Cornell physicist Alex Gaeta, who co-authored the study explains that “any event that occurs at that instant of time won’t lead to scattering of light. It appears as if the event never occurred.”
Still confused? I’m right there with you. Thankfully Gaeta provides a more concrete example of the theory. He conjures up an image familiar to anyone who’s watched a heist film, or the Mission: Impossible movies: a museum exhibit guarded by a crisscrossing array of security lasers. Buckle up, folks, here we go:
Have a laser beam and a detector set up to detect when all of a sudden the beam is broken and there is no light. So if you pass through that beam, an alarm goes off. But what if a device would perhaps speed up a portion of the beam and slow down another portion of it so that there is an instant of time with no beam. You could pass through, and then [on the other side of the event] the device would do the opposite — speed up the part that had been slowed and slow the part that had been sped up. That would put the beam of light back together, so to speak, so the detector would never recognize that anything had happened.
If the concept of speeding up or slowing down individual segments of a laser beam makes your head hurt, you’re not alone. Fortunately the article goes a little deeper to explain how this insane concept is accomplished. During the experiment the scientists have a setup much like the one described above: a laser firing into a probe. Along the way, the beam passes through a piece of equipment given the indescribably awesome name of the “time lens.” The lens, made of a fiber optic glass, intersects the laser beam with a second specialized “pulse” laser that alters the frequency and wavelength of the original beam, which also changes its velocity. Then a second “pulse” laser hits the original beam, restoring its original frequency and wavelength before it hits the probe. Because it has been shifted back to its original properties, the probe cannot detect that anything happened to the beam along the way. In effect, the probe doesn’t recognize that the event happened at all.
It’s hard enough to grasp the basics of this concept, but some of the potential applications are at least a bit easier to wrap your head around. The scientists say that this technique could allow you to add information into a data stream without interrupting the flow. “Using the time lens, you might manipulate the data in almost any way you want and be able to reverse everything afterward,” said Cornell scientist Moti Fridman.
Rumors of a mysterious British man wearing a bowtie seen snooping around the experiment haven’t been verified, nor have sightings of an odd blue police box.