Quantum entanglement is a fascinating phenomenon..

... in quantum mechanics where two or more particles become deeply connected in such a way that the state of one particle is instantly related to the state of another, regardless of the distance between them.

This peculiar connection is maintained even when the entangled particles are far apart and is not constrained by the speed of light, making it seem as though information is being communicated instantaneously, although it cannot be used to transmit information faster than light (no "spooky action at a distance").

To better understand quantum entanglement, let's use an analogy with a pair of entangled dice. Imagine you have two dice that are entangled in such a way that when one die is rolled and shows a particular number, the other die will show the exact opposite number. If you roll one die and it shows a 3, the other die will always show a 4, and vice versa. The dice are entangled, and their outcomes are intrinsically connected.

In quantum systems, instead of dice, we have particles, such as electrons or photons, that can be entangled. When two particles become entangled, their properties, such as spin, position, or polarization, become correlated. Measuring the properties of one entangled particle instantly determines the properties of the other, even if they are separated by vast distances.

Quantum entanglement is a fundamental concept in quantum mechanics and has been experimentally demonstrated in various ways. Entanglement plays a crucial role in quantum computing and quantum communication, as it allows for the creation of qubits that can be manipulated collectively to perform certain types of computations more efficiently or enable secure communication protocols.

Einstein, Podolsky, and Rosen (EPR) famously discussed the concept of entanglement in a thought experiment to highlight what they perceived as a strange feature of quantum theory. Later, experiments like the Bell tests confirmed the existence of entanglement and established that quantum mechanics accurately described the behavior of entangled particles, even if it defied classical intuition. Today, quantum entanglement remains a central aspect of quantum physics and continues to be a subject of active research and exploration.