Entangled State
Introduction
In the field of quantum mechanics, an 'Entangled State' refers to a unique phenomenon where pairs or groups of quantum particles interact in ways such that the quantum state of each particle is dependent on the state of the others, even when the particles are separated by large distances. This concept is a fundamental aspect of quantum mechanics and has profound implications for various fields, including quantum computing, quantum cryptography, and quantum teleportation.
Quantum Entanglement
Quantum entanglement is a physical phenomenon that occurs when a pair or group of particles is generated, interact, or share spatial proximity in a way that the quantum state of each particle cannot be described independently of the state of the other particles, even when the particles are separated by a large distance. The topic of quantum entanglement is one of the most intriguing and counterintuitive in quantum mechanics.
Entanglement and Superposition
Quantum entanglement is closely related to the principle of quantum superposition, which states that a quantum system can exist in multiple states simultaneously until it is measured. When a measurement is made on one entangled particle, the state of the other particle is instantly determined, regardless of the distance between them. This instantaneous action at a distance violates the classical notion of local realism and has been a subject of debate since the early days of quantum mechanics.
Bell's Theorem
Bell's theorem is a crucial theorem in quantum mechanics related to entangled states. Proposed by physicist John Bell in 1964, the theorem provides a test to distinguish between quantum mechanical predictions and classical local hidden variable theories. The results of Bell's theorem experiments have consistently supported the predictions of quantum mechanics, reinforcing the validity of entangled states.
Applications of Entangled States
Entangled states have numerous potential applications in various fields. In quantum computing, entangled states can be used to create quantum bits, or qubits, which can hold more information than classical bits. In quantum cryptography, entangled states can be used to create secure communication channels that are immune to eavesdropping. In quantum teleportation, entangled states can be used to transmit quantum information over large distances.