In 1905, Einstein published his now famous special theory of relativity. It is one of the pillars of modern physics. The special theory of relativity asserts that no physical entity can travel faster than light, since the energy required to enable such a velocity would be infinite. Most of the scientific community extended this concept to communication, asserting that no communication could take place faster than the speed of light. Generally, the scientific community regards light as the upper speed limit of the universe. Until recently, there was no data to contradict this widely held belief.

In 1935, a paper by Albert Einstein, Boris Podolsky, and Nathan Rosen described the EPR paradox (i.e., a thought experiment intended to reveal what they believed to be inadequacies of quantum mechanics) and several papers by Erwin Schrödinger shortly thereafter initiated research into an incredible feature of quantum mechanics, “quantum entanglement.” What made this feature of quantum mechanics incredible is that it appears to allow communication to occur faster than the speed of light. However, we are getting a little ahead of ourselves. Let us first understand what quantum entanglement is and how it relates to communication.

Quantum entanglement is a physical phenomenon that occurs when pairs of particles are generated or interact such that the quantum state of each particle is described relative to each other. Let us consider an example to illustrate this phenomenon. When an electron collides with a positron (i.e., the antimatter counter part of an electron), two photons are emitted. An unusual feature of quantum mechanics is the resultant photons are “entangled.” If one photon exhibits spin up (a component of its angular momentum), the other photon will exhibit spin down. They conserve spin. If you separate the photons and change the spin of either photon, the other will immediately change its spin in a manner to conserve spin. For example, if you change the spin of one photon from spin up to spin down, the other photon, even at a significant distance, will change its spin from spin down to spin up. In other words, they continue to conserve spin.

This phenomenon has been widely verified and the scientific community accepts it as a fundamental feature of quantum mechanics. In recent years, further experimentation related to quantum entanglement has shaken one of the fundamental pillars of modern science, namely, the speed of light as the upper limit that mass or information could travel. Recent experiments (Juan Yin, et al. (2013). “Bounding the speed of `spooky action at a distance”. Phys. Rev. Lett. 110, 260407) have shown that the quantum entanglement information transfer occurs at least 10,000 times faster than the speed of light. It might even be faster. Quantum mechanics holds that the quantum change occurs instantaneously. In other words, the separated particles act as if they were one, even when they are separated by a significant distance. “According to quantum physics, entanglement is independent of distance,” physicist Rupert Ursin of the Austrian Academy of Sciences said in a statement to (reference below).

The phenomenon of quantum entanglement has been demonstrated experimentally with photons, electrons, molecules and even small diamonds. It is real and an area of active research in physics. There is no widely held theory within the scientific community that explains how the particles are able to communicate faster than the speed of light. There are numerous speculations, which I will not go into in this article in the interest of remaining factual.

Anyone who can explain quantum entanglement to the satisfaction of the scientific community is likely a candidate for the Nobel Prize. It has been a mystery for almost a hundred years.


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