At the time of the release of the Princeton Lab findings, the head researcher for the experiment, Dr. Liujun Wang, stated that “Our experiment shows that the generally held misconception that nothing can move faster than the speed of light, is wrong. Einstein’s Theory of Relativity still stands, however, because it is still correct to say that information cannot be transmitted faster than the vacuum speed of light.”

But hold on. Enter quantum physics. In experimental results published on February 8, 2018, in the Journal of Physical Review Letters, in an article entitled, “Two-Way Communication with a Single Quantum Particle,” two quantum physicists,  Jinyang Liang and Lihong V. Wang, from the Unversity of Vienna, demonstrate that quantum systems can surpass the speed limit of light.

Their experiment involves the exchange of a single quantum particle (a photon) by two individuals at the same time with both in receipt of the results in half the normal time of a transmission traveling at the speed of light.

Why is it even possible to exceed the speed of light by double? Because of quantum superposition. That is the single photon each participant in the experiment sends gets canceled or transposed at the same time. The end result, the single photons end up in two places simultaneously.

Is there a practical application for this discovery? Theoretically, this technique could be used for the sending and receiving of secure communications where no third-party could eavesdrop on messages sent and received.

If you are not familiar with superposition, it is a strange phenomenon at the quantum scale. We can observe superposition when we throw two pebbles in a pond and watch the waves created spread in rings until they intersect and cancel out each other.

In quantum states, the analogy of waves on a pond is applicable. The quantum particle strikes the pond surface in one state which then becomes a wave, a series of ripples, a separate state. The ripples move outward and may encounter other ripples which effectively cancel out the wave. What happens to the quantum particle? It still exists but it has undergone a change of states. Thus it is both particle and wave, existing in different states simultaneously.

Some argue that in the experiment described above that the quantum particle in our physical world never really moves because it already exists in the quantum world in two places or two states. Yet we know in this experiment that individual particles have been both fired and received.

Are you confused? Watch this video and maybe it will help.

Of course, this brings up the idea of humanity at some point being able to travel at speeds faster than light, bringing unreachable stars closer to us and making the world of Star Trek no longer science fiction? We have a while to go before anyone can turn a single photon traveling faster than light into a starship doing the same.

The theory of quantum gravity was first postulated by Albert Einstein who proposed back in the 1920s a number of experiments to prove its existence. You see quantum mechanics and gravity seem at cross purposes. The objects quantum physicists study act oddly. They can be particles or act like waves. Think about how light is described as photons (a particle) and also as waves. And also when quantum objects act they can often be in multiple places at once. One cannot say that about you or me. We don’t act like quantum objects at all.

A team at Yale University is creating a device to test gravity at the quantum level. They are doing this with an object that would be considered gigantic on a quantum scale – a drop of superfluid helium a millimeter across. This would be the first time that quantum effects could be observed with the naked eye. The droplet will be suspended in a magnetic field while a photon is fired at it. The superfluid will capture the photon which will bounce around inside it. The quantum effects of the photon will then be studied by observing the motion in the drop.

Practical application of this research could lead to new advances in quantum computing, telecommunications and cryptography. But don’t hold your breath to see results soon. The experiment is expected to last five years before definitive study results get reported in physics’ journals.

The above illustration is an artist’s rendition of what a levitated drop of superfluid helium would look like with a single photon (the red arrows) circulating within it. Note the droplet when impacted by the photon produces a superposition, being in two places at the same time. The gravitational field is represented schematically beneath the superfluid drop and may limit the superposition effect.