Niels Bohr as philosopher of experiment: Does
... regard for the subtle but important distinctions. While Bohr often left it to his readers to decipher the precise meaning of ambiguous phrases such as “classical description,” in his more deliberate moments he did take care to distinguish between the use of classical concepts (such as position and m ...
... regard for the subtle but important distinctions. While Bohr often left it to his readers to decipher the precise meaning of ambiguous phrases such as “classical description,” in his more deliberate moments he did take care to distinguish between the use of classical concepts (such as position and m ...
6 Product Operators
... In this section we will review a few key concepts before moving on to a description of the product operator formalism. In quantum mechanics, two mathematical objects – wavefunctions and operators – are of central importance. The wavefunction describes the system of interest (such as a spin or an ele ...
... In this section we will review a few key concepts before moving on to a description of the product operator formalism. In quantum mechanics, two mathematical objects – wavefunctions and operators – are of central importance. The wavefunction describes the system of interest (such as a spin or an ele ...
How far are we from the quantum theory of gravity?
... theory. When a path integral is involved it should be fully defined in terms of a well defined measure, or else expressed as a discrete summation. This led in each case to two lists, the first of results, the second of conjectures and open issues. These are summarized in Table 1, which indicates th ...
... theory. When a path integral is involved it should be fully defined in terms of a well defined measure, or else expressed as a discrete summation. This led in each case to two lists, the first of results, the second of conjectures and open issues. These are summarized in Table 1, which indicates th ...
XVIIth International Workshop on Quantum Atomic and Molecular
... of in classical mechanics have been discovered and continue to be discovered at a regular rate, with also many applications in chemistry and molecular physics. We look forward to learning about some of the most recent and exciting developments in this field. Slight changes have been applied to the p ...
... of in classical mechanics have been discovered and continue to be discovered at a regular rate, with also many applications in chemistry and molecular physics. We look forward to learning about some of the most recent and exciting developments in this field. Slight changes have been applied to the p ...
Confusions about fuzzballs and the information paradox
... world to argue that there will be no problem when black holes form. Hawking believer: Good, that is correct. So now me let me ask the same question about AdS/CFT. You have computed the spectrum , 2-point functions, 3 point functions etc. and found agreement between the CFT and gravity descriptions. ...
... world to argue that there will be no problem when black holes form. Hawking believer: Good, that is correct. So now me let me ask the same question about AdS/CFT. You have computed the spectrum , 2-point functions, 3 point functions etc. and found agreement between the CFT and gravity descriptions. ...
Optical probing of spin fluctuations of a single paramagnetic Mn
... component corresponds to the radiative lifetime of the exciton as already measured in nonmagnetic QDs. The long component is associated with the existence of the dark excitons.12,13 Direct recombination of the dark exciton can be observed in some Mn-doped QDs because of a slight admixture of the bri ...
... component corresponds to the radiative lifetime of the exciton as already measured in nonmagnetic QDs. The long component is associated with the existence of the dark excitons.12,13 Direct recombination of the dark exciton can be observed in some Mn-doped QDs because of a slight admixture of the bri ...
ZONOIDS AND SPARSIFICATION OF QUANTUM
... In this paper we consider a special class of vector measures: Positive Operator-Valued Measures (POVMs). In the formalism of quantum mechanics, POVMs represent the most general form of a quantum measurement. Recently, Matthews, Wehner and Winter [22] introduced the distinguishability norm associated ...
... In this paper we consider a special class of vector measures: Positive Operator-Valued Measures (POVMs). In the formalism of quantum mechanics, POVMs represent the most general form of a quantum measurement. Recently, Matthews, Wehner and Winter [22] introduced the distinguishability norm associated ...
No. 18 - Department of Mathematics
... related to the superconformal symmetry algebra psu(2, 2|4). We also discuss general features of classical integrability, higher charges and Lax pairs, using as a toy model the theory of the principal chiral field (14). Starting from section 4, we enter the core of the topic of this review, i.e. the ...
... related to the superconformal symmetry algebra psu(2, 2|4). We also discuss general features of classical integrability, higher charges and Lax pairs, using as a toy model the theory of the principal chiral field (14). Starting from section 4, we enter the core of the topic of this review, i.e. the ...
PDF file - Comp Chem - University of Minnesota
... analytic expressions for the potential energy surfaces in eqn. (4) and their couplings. As discussed above, there are two possibilities for representing a set of coupled potential energy surfaces, the unique adiabatic representation or a nonunique diabatic one. They each have strengths and weaknesse ...
... analytic expressions for the potential energy surfaces in eqn. (4) and their couplings. As discussed above, there are two possibilities for representing a set of coupled potential energy surfaces, the unique adiabatic representation or a nonunique diabatic one. They each have strengths and weaknesse ...
DECOHERENCE AND DYNAMICAL DECOUPLING IN SOLID-STATE SPIN QUBITS Wayne Martin Witzel
... mixture) of both zero and one. More importantly, multiple qubits, stored in the states of different subatomic particles for example, can become entangled so that their superposition states are interdependent; that is, the state of the system can be an arbitrary superposition of various possible syst ...
... mixture) of both zero and one. More importantly, multiple qubits, stored in the states of different subatomic particles for example, can become entangled so that their superposition states are interdependent; that is, the state of the system can be an arbitrary superposition of various possible syst ...
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.