The Use and Abuse of “photon” in Nanomechanics – pdf
... While it has different meanings in different contexts, here semiclassical approximation refers to a treatment of the interaction of light and matter in which the material particles are described quantum mechanically and the electromagnetic fields are described classically, using Maxwell’s equations. ...
... While it has different meanings in different contexts, here semiclassical approximation refers to a treatment of the interaction of light and matter in which the material particles are described quantum mechanically and the electromagnetic fields are described classically, using Maxwell’s equations. ...
... to high-energy processes. This derives partly from the rapid development of collision experiments and partly from the fact that the requirement of relativistic invariance played a central role in the creation of the theory. It was still naively assumed that the conflict between Maxwell’s and Planck’ ...
Triadic Quantum Energy
... Quite at the same times Albert Einstein (1905) transforms the Newtonian separation of space from time, before considered as different absolute entities, combining both in the four vectors dimensions e.g. into a single construct called the space‐time ...
... Quite at the same times Albert Einstein (1905) transforms the Newtonian separation of space from time, before considered as different absolute entities, combining both in the four vectors dimensions e.g. into a single construct called the space‐time ...
quantum computing (ppt, udel.edu)
... information in a gate will cause heat to be evolved which can destroy the superposition of qubits. ...
... information in a gate will cause heat to be evolved which can destroy the superposition of qubits. ...
Quantum Computer - Physics, Computer Science and Engineering
... computation. i.e. we can perform any quantum computation by connecting just 1-qubit rotation gates and controlled-NOT gates (cf. any classical computation can be realized using just AND and ...
... computation. i.e. we can perform any quantum computation by connecting just 1-qubit rotation gates and controlled-NOT gates (cf. any classical computation can be realized using just AND and ...
Verification of Concurrent Quantum Protocols by Equivalence
... communication and cryptography have made large strides and is now well established. Physical restrictions of quantum communication, like preserving photon states over long distances, are gradually being resolved, for example, by quantum repeaters [11] and using quantum teleportation. Various Quantum ...
... communication and cryptography have made large strides and is now well established. Physical restrictions of quantum communication, like preserving photon states over long distances, are gradually being resolved, for example, by quantum repeaters [11] and using quantum teleportation. Various Quantum ...
On Quantum Generalizations of Information
... Another way of making this obvious is to compare A’s and B’s eigen bases. If there is some one-to-one alignment between A’s and B’s eigen kets such that |ak i = |bk i for k = 1, ..., min(n, m) then we do not have a quantum effect. In this case the interaction of A and B reduces to the classical case ...
... Another way of making this obvious is to compare A’s and B’s eigen bases. If there is some one-to-one alignment between A’s and B’s eigen kets such that |ak i = |bk i for k = 1, ..., min(n, m) then we do not have a quantum effect. In this case the interaction of A and B reduces to the classical case ...
Quantum key distribution
Quantum key distribution (QKD) uses quantum mechanics to guarantee secure communication. It enables two parties to produce a shared random secret key known only to them, which can then be used to encrypt and decrypt messages. It is often incorrectly called quantum cryptography, as it is the most well known example of the group of quantum cryptographic tasks.An important and unique property of quantum key distribution is the ability of the two communicating users to detect the presence of any third party trying to gain knowledge of the key. This results from a fundamental aspect of quantum mechanics: the process of measuring a quantum system in general disturbs the system. A third party trying to eavesdrop on the key must in some way measure it, thus introducing detectable anomalies. By using quantum superpositions or quantum entanglement and transmitting information in quantum states, a communication system can be implemented which detects eavesdropping. If the level of eavesdropping is below a certain threshold, a key can be produced that is guaranteed to be secure (i.e. the eavesdropper has no information about it), otherwise no secure key is possible and communication is aborted.The security of encryption that uses quantum key distribution relies on the foundations of quantum mechanics, in contrast to traditional public key cryptography which relies on the computational difficulty of certain mathematical functions, and cannot provide any indication of eavesdropping at any point in the communication process, or any mathematical proof as to the actual complexity of reversing the one-way functions used. QKD has provable security based on information theory, and forward secrecy.Quantum key distribution is only used to produce and distribute a key, not to transmit any message data. This key can then be used with any chosen encryption algorithm to encrypt (and decrypt) a message, which can then be transmitted over a standard communication channel. The algorithm most commonly associated with QKD is the one-time pad, as it is provably secure when used with a secret, random key. In real world situations, it is often also used with encryption using symmetric key algorithms like the Advanced Encryption Standard algorithm. In the case of QKD this comparison is based on the assumption of perfect single-photon sources and detectors, that cannot be easily implemented.