Time travel has always fascinated fans of science fiction. While science says traveling to the future is possible if you can move close to the speed of light, going back in time is impossible. But what if scientists could use the strange rules of quantum physics to learn about past events? New research shows this idea might not be so far-fetched.

A recent study in Physical Review Letters by Kater Murch, a physics professor at Washington University in St. Louis, and his colleagues Nicole Yunger Halpern and David Arvidsson-Shukur, describes a new type of sensor that uses quantum entanglement to “travel” back in time.

Murch explains that this idea is like sending a telescope back in time to see a shooting star you missed. In our regular world, this is impossible. But in the weird world of quantum physics, it might be possible. This is due to a special feature of quantum sensors called “retrospection”.

Here’s how it works: Scientists start by connecting two tiny particles called qubits so their properties are linked, no matter how far apart they are. Imagine you have two spinning tops (qubits) that are spinning in opposite directions. One top, called the “probe”, is exposed to a magnetic field, making it spin differently.

Now comes the magic part. When scientists measure the second top (the one not exposed to the magnetic field), its state somehow sends information “back in time” to the first top. This helps scientists figure out what happened to the first top when it was spinning in the magnetic field.

Usually, in experiments like this, there is a one-in-three chance that the measurement will not work because the magnetic field might not affect the qubit in a way that is easy to measure. Scientists often have to guess which way to prepare the spin, and they might get it wrong a third of the time. But with retrospection, they can look back and set the best direction for the spin using information from the future.

Einstein called quantum entanglement “spooky action at a distance” because it’s so strange. The oddest part is that we can think of these entangled particles as the same particle moving through time. This helps scientists create better sensors that can, in a sense, travel back in time.

These time-traveling sensors could be used for many things, like studying astronomical events or understanding magnetic fields better. As scientists explore this concept further, more uses will likely be discovered.


SOURCES

Washington University in St.Louis

Xingrui Song, Flavio Salvati, et al., Agnostic Phase Estimation. Phys. Rev. Lett. 132, 260801. doi.org/10.1103/PhysRevLett.132.260801


  • Share on:

Discover more from LBV Magazine English Edition

Subscribe to get the latest posts sent to your email.

Something went wrong. Please refresh the page and/or try again.