What Is the Spooky Science of Quantum Entanglement?
Learn how particles engage in a mind-boggling phenomenon that forms the backbone of quantum mechanics.
There’s a lot we don’t know about our universe — in fact, 95% of it remains a mystery to us. That’s why scientists continue to probe our understanding of quantum physics.
There are many facets to quantum science, but let’s zoom in on something that Albert Einstein called “spooky action at a distance”: quantum entanglement.
What is Quantum Entanglement?
Quantum science explores and helps explain some of the strangest phenomena in the universe, even shedding light on the mystery of dark matter and dark energy. Quantum is the study of atoms and subatomic particles, and how they interact with each other. It examines the very stuff we, and everything around us, are made of.
One of the most far-out phenomena of quantum theory is quantum entanglement, the idea that particles of the same origin, which were once connected, always stay connected. Even if they separate and move far apart in time and space, they continue to share something beyond a mere bond — they shed their original quantum states and take on a new, united quantum state which they maintain forever. This means if something happens to one particle, it affects all the others with which it’s entangled.
A “Spooky” Science
In 1935, Albert Einstein and colleagues first pointed out the “spooky” action of quantum entanglement. Quantum entanglement, however, appeared to conflict with Einstein’s theory of special relativity, which postulates that nothing can travel faster than the speed of light and is demonstrated mathematically by the well-known equation E=mc2.
The ability to instantaneously measure the quantum state of one particle by measuring that of its entangled partner somewhere else in the universe means that that information would have to be delivered faster than lightspeed. This contradicts Einstein’s theory of special relativity. What also remains a mystery is how exactly these particles can interact from such a far distance to share information.
Three decades would pass until another scientist, John Stewart Bell, would develop a method to test the phenomenon, which ultimately enabled later scientists to confirm quantum entanglement.
Classical vs. Quantum Physics
If classical physics is life as we know it, the quantum world is like an alternate universe.
Classical physics is the force governing an extremely predictable world, where an apple set on a table stays there until something causes it to move again.
In the quantum world, not only can the apple end up on Mars, but, hypothetically, it could exist both on the table and on Mars at the same time. It could even be inextricably tied to another apple in some other part of the universe through entanglement. Thus, “reality” as we know it is much more uncertain, with the possibility for many solutions or outcomes to exist, rather than just one.
Quantum entanglement remains a spooky part of our world. Check out the resources below to learn more about how NASA scientists are working to unravel the mysteries of our quantum universe.
Related Resources:
NASA’s Biological and Physical Sciences Division pioneers scientific discovery and enables exploration by using space environments to conduct investigations not possible on Earth. Studying biological and physical phenomenon under extreme conditions allows researchers to advance the fundamental scientific knowledge required to go farther and stay longer in space, while also benefitting life on Earth.