Mark Megahan
Back in 1993, when late physicist Asher Peres was asked about quantum teleportation, he explained it wouldn’t transport the body, just the soul. That’s what they did at QuTech recently. Instant transmission of information just materialized off the pages of science fiction and into the lab.
Teleportation at quantum level
Quantum computing is such a freaky new science, even the researchers don’t understand how it works half the time. That’s okay because uncertainty is what makes the universe go ’round. The field has managed a steady stream of both tiny steps forward and major leaps.
One of those huge breakthroughs happened at Delft University in the Netherlands, teleportation. Ronald Hanson and his team “succeeded in teleporting quantum information via a rudimentary network with no direct connection between sender and receiver.” It’s literally a quantum leap.
Officially published in Nature recently, Hanson’s quantum teleportation discovery “means we are one step closer to a quantum internet which would then lead to an entirely new kind of computer that could carry out tasks that would take supercomputers thousands of years in a matter of minutes.”
An even more exciting possibility is the application for faster than light communications. The concept starts with “entanglement,” then takes it to the next level.
In the first part of the team’s research, they accomplished the easy part. Basic teleportation to a pair of “points” or “adjacent nodes” they call Alice and Bob. It was a nice trick, but easy because they’re closely connected. Hanson lights the hoop on fire for his next feat. The work which got them published in Nature was when they hooked Alice up with Charlie. He’s not right next door. Quantum relativistically speaking, he’s across town. They used Bob to make the introduction.
“The trio form the first network that, although rudimentary, allows us to contemplate a quantum internet, with infinite possibilities for computation and for observing a hitherto unknown world.”
No direct connection
The great thing about this, Hanson gloats, is that their work “shows how teleportation can be used in a real network environment, with nodes that have no direct connection.” When we finally get the quantum internet going, his technique will “be the main way to transfer quantum information over large distances.”
Think of it as “a modular quantum computer where the nodes are the modules.” They proved “that nodes can exchange quantum information, even if they are not on a single chip.” They can be on opposite sides of the universe.
Albert Einstein would still call it “spooky action at a distance,” but even he would have to admit that information itself was really teleported, it didn’t travel through space or through a conductor. The big breakthrough came from figuring out it takes two to tango, or in this case tangle.
Teleportation starts by entangling one particle with another. When that happens, both lose their individual identities and become a “system with a single wave function.” Measuring the state of Alice makes Bob show the same reading instantly.
Hanson and his team figured out how to make a direct connection between Alice and Charlie by connecting both to Bob.
Alice and Bob get things started “using an intertwined state between each other, one which Bob stores, freeing him up to create an entanglement with Charlie.” It sounds like a swing party. “After preparing an entanglement between Alice and Charlie, the state to be teleported is created and then executed,” Hanson describes.
“What happens then is something that is only possible in the quantum world: as a result of the measurement, the information disappears from Charlie’s side and immediately appears on Alice’s side.” Teleportation is here. Beam me up Scotty!
