**
Overview
Quantum entanglement is a phenomenon in which two or more particles become correlated in such a way that the state of one particle cannot be described independently of the others, even when they are separated by large distances. This means that measuring the state of one particle will instantly affect the state of the other entangled particles, regardless of the distance between them. Entanglement is a key feature of quantum mechanics, and it has been experimentally confirmed numerous times since its discovery in the early 20th century.
Entanglement is often illustrated using the example of two spin-1/2 particles, such as electrons. When these particles are entangled, their spins become correlated in a way that cannot be explained by classical physics. For example, if one electron is spinning clockwise, the other electron will be spinning counterclockwise, and vice versa. This correlation is not limited to the spins of the particles; entanglement can also occur in other properties, such as polarization and energy.
Entanglement has been shown to have a number of fascinating consequences, including the ability to instantaneously transmit information between particles, regardless of the distance between them. This has led to a number of applications in quantum computing, quantum cryptography, and quantum teleportation.
History/Background
The concept of entanglement was first introduced by Albert Einstein, Boris Podolsky, and Nathan Rosen in 1935, in a paper titled "Can Quantum-Mechanical Description of Physical Reality be Considered Complete?" (EPR paper). In this paper, the authors proposed a thought experiment, known as the EPR paradox, which challenged the completeness of quantum mechanics. The EPR paradox suggested that if two particles were entangled, measuring the state of one particle would instantly affect the state of the other, regardless of the distance between them.
The concept of entanglement was later developed by David Bohm and John Bell, who showed that entanglement was a fundamental feature of quantum mechanics. In the 1960s and 1970s, entanglement was experimentally confirmed by a number of researchers, including John Clauser and Stuart Freedman.
Key Information
* Entanglement is a fundamental feature of quantum mechanics, and it has been experimentally confirmed numerous times.
* Entangled particles can be separated by large distances, and measuring the state of one particle will instantly affect the state of the other.
* Entanglement is a key feature of quantum computing, and it has been used to demonstrate quantum teleportation and quantum cryptography.
* Entanglement is a fundamental aspect of quantum field theory, and it has been used to describe the behavior of particles in high-energy collisions.
Significance
Entanglement is a fundamental concept in quantum mechanics, and it has a number of significant implications for our understanding of the universe. Entanglement has been shown to have a number of fascinating consequences, including the ability to instantaneously transmit information between particles, regardless of the distance between them. This has led to a number of applications in quantum computing, quantum cryptography, and quantum teleportation.
Entanglement has also been used to demonstrate the power of quantum mechanics, and it has been used to challenge our understanding of space and time. The concept of entanglement has been shown to be a fundamental aspect of quantum field theory, and it has been used to describe the behavior of particles in high-energy collisions.