Quantum Physics

Which time travel movie got the rules right? According to experiments using a quantum time travel simulator, reality is “self-healing,” so changes made to the past won’t drastically alter the future you came from – at least, in the quantum realm.

Using just a few hundred identical atoms, physicists at the Max Planck Institute of Quantum Optics have pieced together the world’s lightest mirror, which is invisible to the naked eye and has a surface measured in mere microns.

Classical physics describes how large objects and systems work on an everyday scale, while quantum physics describes the “spooky” subatomic world. Now scientists have observed a rare crossover where a quantum fluctuation affected a macroscale object.

In quantum entanglement, particle links are thought to be fragile. But now, physicists have managed to produce hot clouds of trillions of entangled atoms, breaking quantity records and showing that entanglement isn’t as fragile as previously thought.

Physicists have harnessed the weird world of quantum physics to develop a “quantum radar” prototype. The system uses the quantum entanglement phenomenon to detect objects, and it could eventually outperform conventional radar in some circumstances.

A new experiment shows that even massive molecules containing up to 2,000 atoms can exist in two places simultaneously.

​​Quantum entanglement, where two objects become intertwined and remain so no matter the distance that grows between them, is a tricky phenomenon to study let alone photograph. But scientists doing the former have now managed the latter, for the first time ever.

Researchers have produced what may very well be the first pieces of art made using non-classical matter. The team has reproduced classic artworks like the Mona Lisa and Starry Night on a “quantum canvas” as small as a human hair, by projecting light onto Bose-Einstein condensates (BECs).

If you throw a particle at a wall, there’s a chance that it will suddenly appear on the other side. This is thanks to a phenomenon known as quantum tunneling, and now a team of physicists has measured just how long that process takes.

Practical quantum computers may be another step closer to reality, thanks again to graphene. The bits of information in quantum computers (qubits) can exist in two states at once, and now researchers have managed to record just how long that superposition state can last in a qubit made of graphene.

The tractor beam is a long-time staple of sci-fi, but now Australian researchers have created a real-world version. While it won’t exactly be capturing enemy spaceships anytime soon, the device can use light to pull in and trap atoms, which may be handy for quantum communications or memory systems.

Quantum entanglement is an eerie concept that Einstein himself had trouble accepting, and yet it’s been experimentally demonstrated. To find out whether there are other variables, a new experiment provides the strongest evidence so far of quantum entanglement or a 12-billion year “conspiracy."