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Breaking the speed limit of the universe.

Albert Einstein was the first to show that light travels at the same speed everywhere in the universe — a modest rate of 670,616,619 miles per hour. He also developed the fundamental equation E=mc2 in his Special Theory of Relativity, which predicted that nothing with mass can travel faster than the speed of light. What makes light so special? It doesn’t have a resting mass.

And for years, it was believed that nothing could travel faster — but it turns out that is not entirely true.

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Particles have been accelerated to 99.99 percent the speed of light in accelerators such as the Large Hadron Collider. However, according to David Gross, a Physics Nobel Laureate, these particles will never reach the speed of light because they have mass.

But certain entities have been found to reach faster-than-light, or superluminal speeds, while still maintaining validity to Einstein’s theory of special relativity. This is possible because it turns out that particles of light are not the only massless entities that exist in the universe.

Shadows

In principle, shadows can move faster than the speed of light. “Strictly speaking dark cannot have a speed,” says Pete Edwards of Durham University. “It does not move or travel in any way. However, if we think of dark as the absence of light, dark is chased away by light and so it disappears at the same speed as light arrives. In this sense the speed of dark is equivalent to the speed of light.”

Along some distance, a shadow can become larger than the object creating it. When a shadow is bigger than the object casting it, it moves at a greater distance but in the same amount of time. If the shadow is large enough, it could move across the surface faster than light.

This is an illusion that darkness travels faster than the speed of light, and it is still agreed that no physical object can travel faster — since darkness has no mass.

Empty Space

Empty space does not contain material or information, therefore, it is massless. “Since nothing is just empty space or vacuum, it can expand faster than light speed since no material object is breaking the light barrier,” said theoretical astrophysicist Michio Kaku from Big Think. “Therefore, empty space can certainly expand faster than light.”

Physicists believe this is what happened immediately following the Big Bang — within a trillionth of a trillionth of a second, the universe doubled in size repeatedly, resulting in the outer edge of the universe expanding much faster than the speed of light.

Quantum Entanglement

Quantum entanglement is the strange phenomena where two particles are inexplicably linked and communicate even though they may be separated by distances as far as thousands of light years.

What physicists found is that this communication can happen faster than the speed of light. Kaku explained, “If I jiggle one electron, the other electron ‘senses’ this vibration instantly, faster than the speed of light.”

Wormholes

A wormhole is a theoretical entity that would allow something or someone to travel vast distances instantaneously. If wormholes exist (the debate is still ongoing), then, “The only viable way of breaking the light barrier may be through General Relativity and the warping of space time,” Kaku writes.

Even if wormholes did exist, before anything could travel through them, something would have to keep them open. That “something” is what scientists call exotic material. Amazingly, this exotic material can exist according to the laws of quantum physics, and has even been created in physics laboratories — just in very small amounts.

It is still unknown if enough exotic material could exist in the universe to keep a wormhole open.

So the next time you are in the mood to break the light barrier, go ahead, shadowplay.