Quantum Entanglement
the art of being in two places at the same time
Most of us have heard of this weird property of sub-atomic particles which Albert Einstein referred to as “spooky action at a distance”. Quantum entanglement is one of the most perplexing and astonishing concepts in the field of physics, and while it may sound like the stuff of science fiction, it is a well-established and experimentally verified phenomenon.
Imagine two particles, say electrons, that have a special connection. When they are entangled, the state of one particle instantly affects the state of the other, no matter how far apart they are. It’s as if they have a telepathic link that transcends the boundaries of space and time.
To begin to understand this concept in everyday terms, we first have to consider a property of these particles, known as Superposition.
Superposition: In the quantum world, particles can exist in a state of superposition, meaning they can be in multiple states simultaneously. When two entangled particles are in a superposition, their properties are intertwined. One of these properties is called spin, and they can be spin-up or spin-down, and each one can even be in spin-up and spin-down at the same time.
Note: this is not actually spin as we know it, it is simply a way to describe one of the properties of sub-atomic particles that even physicists cannot describe in everyday terms.
For example, if one particle is in a superposition of spin-up and spin-down, the other will also be in the same superposition.
But as soon as we measure one of these particles, the result of that measurement will affect its partner particle instantly, no matter if both particles are separated by a vast distance. The very act of measuring one instantly affects the other.
If we look at this in practice:
In the case of entangled particles, when one particle is measured and found to be in a specific state, such as spin-up, its entangled partner will be instantaneously determined to be in the opposite state, that is spin-down. This phenomenon is a consequence of the principle of quantum entanglement.
Let’s say we have two entangled particles, Particle A and Particle B, in a superposition of spin-up and spin-down. If you measure Particle A and find it to be in a spin-up state, you’ll know that Particle B is in a spin-down state, even if Particle B is located far away from Particle A, say on the other side of the Galaxy,.
This instant correlation between the measurements of entangled particles is a fundamental aspect of quantum entanglement, and it’s sometimes referred to as “spooky action at a distance.”
So, even when these entangled particles are separated by vast distances, measurements made on one particle instantaneously dictate the outcome of measurements on the other, creating a correlation that defies classical physics.
This demonstrates the principle of non-locality, suggesting that information can travel faster than the speed of light. This idea challenges our understanding of causality and space-time.
However, The famous Bell’s Theorem suggests that quantum entanglement cannot be explained by any hidden variables, this implies that the entangled particles are not following predetermined paths or obeying hidden laws but are genuinely interconnected in a way that defies classical intuition.
It’s as if both particles are still acting as part of a whole, regardless of distance between them.
Entanglement has paved the way for quantum computing, a revolutionary technology with the potential to solve complex problems at speeds unimaginable by classical computers. Quantum computers use entangled qubits, enabling them to perform calculations that were once thought impossible.
