algunos resultados asociados a problemas
... case must be considered. Namely, the case where the particle disappears upon reaching a wall and then appears at the other end must be considered. This type of movement (which is very unusual because the particle is not actually trapped between the two walls) corresponds to that of a quantum particl ...
... case must be considered. Namely, the case where the particle disappears upon reaching a wall and then appears at the other end must be considered. This type of movement (which is very unusual because the particle is not actually trapped between the two walls) corresponds to that of a quantum particl ...
quantum computing for computer scientists
... subtraction is not ( a b b a ), we use the convention that the sign of the coefficient must always be associated with the particular element, for example, a b = a + b = b + a = b + a . The interpretation of 0 to mean cannot occur [6] is subtle, yet conceptually meaningful, and has these con ...
... subtraction is not ( a b b a ), we use the convention that the sign of the coefficient must always be associated with the particular element, for example, a b = a + b = b + a = b + a . The interpretation of 0 to mean cannot occur [6] is subtle, yet conceptually meaningful, and has these con ...
AN INDEX THEORY FOR QUANTUM DYNAMICAL SEMIGROUPS 1
... semigroup is uniquely determined up to unitary isomorphisms. We define the index of T by simply taking it as index of θ. It is seen to be anti-isomorphic to the product system P obtained earlier. Here we emphasize that the index is important for us not only because it gives an invariant for the semi ...
... semigroup is uniquely determined up to unitary isomorphisms. We define the index of T by simply taking it as index of θ. It is seen to be anti-isomorphic to the product system P obtained earlier. Here we emphasize that the index is important for us not only because it gives an invariant for the semi ...
No information without manipulation - Philsci
... information; the capacity of a channel is measured in bits per second. To the extent that the unity of measurement of information is involved in the calculations side by side with the unities of traditional physical magnitudes, it is not easy to resist the temptation of conceiving information also ...
... information; the capacity of a channel is measured in bits per second. To the extent that the unity of measurement of information is involved in the calculations side by side with the unities of traditional physical magnitudes, it is not easy to resist the temptation of conceiving information also ...
Consequences of postselection - Conference in honor of John
... by fault-tolerant gadgets, and if the physical noise model is sufficiently benign, k levels of concatenation allows simulation of a logical computation at an effective noise rate O(²2k) if the physical noise rate is ² . Thus k ¼ O(log n) levels are sufficient to maintain the desired accuracy, and th ...
... by fault-tolerant gadgets, and if the physical noise model is sufficiently benign, k levels of concatenation allows simulation of a logical computation at an effective noise rate O(²2k) if the physical noise rate is ² . Thus k ¼ O(log n) levels are sufficient to maintain the desired accuracy, and th ...
“Anticoherent” Spin States via the Majorana Representation
... vertices together comprise the vertices of a dodecahedron. (See Fig. 2.) This configuration offers a highly symmetrical way of inscribing five tetrahedra in the sphere. Now, as the tetrahedral perfect states happen to “live” in a space of five dimensions, a question naturally presents itself: Is it ...
... vertices together comprise the vertices of a dodecahedron. (See Fig. 2.) This configuration offers a highly symmetrical way of inscribing five tetrahedra in the sphere. Now, as the tetrahedral perfect states happen to “live” in a space of five dimensions, a question naturally presents itself: Is it ...
Product Operator - Vanderbilt Center for Structural Biology
... composite pulses,‘27,28’measurement of slow chemical exchange(22~38’and spin imaging.@‘) 2.2. Semiclassical Vector Models In multi-level systems, it is possible to assign a vector to each individual transition. The effects of selective pulses and precession can still be understood on classical groun ...
... composite pulses,‘27,28’measurement of slow chemical exchange(22~38’and spin imaging.@‘) 2.2. Semiclassical Vector Models In multi-level systems, it is possible to assign a vector to each individual transition. The effects of selective pulses and precession can still be understood on classical groun ...
Full paper
... spatial superposition, and hence the way should be open to perform controlled decoherence experiments with large masses. Our experiment is based on an optical interferometer to probe the state of an oscillating mass, e.g., a nanobead or a mechanical oscillator. Contrary to previous work concerning o ...
... spatial superposition, and hence the way should be open to perform controlled decoherence experiments with large masses. Our experiment is based on an optical interferometer to probe the state of an oscillating mass, e.g., a nanobead or a mechanical oscillator. Contrary to previous work concerning o ...
The many-worlds interpretation of quantum - Philsci
... while it uses Gleason’s theorem to avoid Everett’s assumption that the probability of a wavefunction component can depend only on its squared modulus, does not justify the noncontextuality assumption implicit in Gleason’s theorem. There are also more minor exceptions—for instance, I now see somewhat ...
... while it uses Gleason’s theorem to avoid Everett’s assumption that the probability of a wavefunction component can depend only on its squared modulus, does not justify the noncontextuality assumption implicit in Gleason’s theorem. There are also more minor exceptions—for instance, I now see somewhat ...
Photon echoes for a system of large negative spin and few mean
... field with small mean photon number in a closed cavity. This particular example in a crowded active field of research has been overlooked. The interaction of TLMs interacting with a field in a closed cavity is well known and has been covered extensively, as will be seen in the next section. An exami ...
... field with small mean photon number in a closed cavity. This particular example in a crowded active field of research has been overlooked. The interaction of TLMs interacting with a field in a closed cavity is well known and has been covered extensively, as will be seen in the next section. An exami ...
NON-RELATIVISTIC QUANTUM MECHANICS - Philsci
... makes the determination of probabilities and expected values trivial. Indeed, even when dealing with general states, it is often convenient to write F in terms of its spectral decomposition, and the state in terms of a basis determined by F . 1.2.3.2.b. Superposition. It is a standard assumption of ...
... makes the determination of probabilities and expected values trivial. Indeed, even when dealing with general states, it is often convenient to write F in terms of its spectral decomposition, and the state in terms of a basis determined by F . 1.2.3.2.b. Superposition. It is a standard assumption of ...
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.