E + - IPAM
... Hamiltonian if it acts on a system of d-state particles and can be written as a sum of terms, each of which acts non-trivially on a set of k particles. • H is an r-dimensional d-state Hamiltonian if it is a d-state 2-local Hamiltonian and each term interacts non-trivially on only nearest neighbor pa ...
... Hamiltonian if it acts on a system of d-state particles and can be written as a sum of terms, each of which acts non-trivially on a set of k particles. • H is an r-dimensional d-state Hamiltonian if it is a d-state 2-local Hamiltonian and each term interacts non-trivially on only nearest neighbor pa ...
ppt
... How much of the stuff on the previous slide can we measure from the QS itself... ... or a polynomial number of copies of it? Does there exist physical quantities extractable from poly copies of a QS which requires exponential CC? “The strongest argument indicating that the simulation of QS is a hard ...
... How much of the stuff on the previous slide can we measure from the QS itself... ... or a polynomial number of copies of it? Does there exist physical quantities extractable from poly copies of a QS which requires exponential CC? “The strongest argument indicating that the simulation of QS is a hard ...
Presentation
... without presence of speckles. Some inconsistency may occur due to choose of inaccurate optical properties of the simulated object. ...
... without presence of speckles. Some inconsistency may occur due to choose of inaccurate optical properties of the simulated object. ...
A Study on Reversible Logic Gates of Quantum Computing
... though a qubit has discrete eigenstates, there is something analog about it also in the continuous range of superposition states that it can take on. In recent years quantum computing becomes a forefront research in the field of algorithms, cryptography and artificial intelligence [5,6].We can descr ...
... though a qubit has discrete eigenstates, there is something analog about it also in the continuous range of superposition states that it can take on. In recent years quantum computing becomes a forefront research in the field of algorithms, cryptography and artificial intelligence [5,6].We can descr ...
Dirac`s coincidences sixty years on
... to offer a way of calculating the quantum vacuum energy density – the big problem for field theorists. But its chances of success hardly seem bright, as it depends even more sensitively than (10) on its sole free parameter. Yet if we plug in some plausible candidates for the massscale for (11), some ...
... to offer a way of calculating the quantum vacuum energy density – the big problem for field theorists. But its chances of success hardly seem bright, as it depends even more sensitively than (10) on its sole free parameter. Yet if we plug in some plausible candidates for the massscale for (11), some ...
Generalising Unitary Time Evolution
... behave identically to physical systems. While entanglement and measurement are commonly used by QI models, almost none of them show how a quantum-like system might evolve to the point where it could be measured. One of the most commonly used techniques in the modelling of physical systems involves s ...
... behave identically to physical systems. While entanglement and measurement are commonly used by QI models, almost none of them show how a quantum-like system might evolve to the point where it could be measured. One of the most commonly used techniques in the modelling of physical systems involves s ...
Quantum Error Correction and Orthogonal Geometry
... A quantum error-correcting code is a way of encoding quantum states into qubits (two-state quantum systems) so that error or decoherence in a small number of individual qubits has little or no effect on the encoded data. The existence of quantum error-correcting codes was discovered only recently [1 ...
... A quantum error-correcting code is a way of encoding quantum states into qubits (two-state quantum systems) so that error or decoherence in a small number of individual qubits has little or no effect on the encoded data. The existence of quantum error-correcting codes was discovered only recently [1 ...
UNIT ONE: KEY TERMS Learn(ing)
... 5. Write synonyms and a definition for each of the terms you listed in problem #2. a. b c. ...
... 5. Write synonyms and a definition for each of the terms you listed in problem #2. a. b c. ...
Quantum energy gaps and first-order mean-field transitions
... the WKB approximation it is well known that a quantum particle tunnels rapidly through very high (in energy) but thin (in distance) energy barriers. Thermal annealing is much better at low, but deep barrier crossing. However, in a first-order transition the two states whose free energies cross are g ...
... the WKB approximation it is well known that a quantum particle tunnels rapidly through very high (in energy) but thin (in distance) energy barriers. Thermal annealing is much better at low, but deep barrier crossing. However, in a first-order transition the two states whose free energies cross are g ...
Fysiikan seminaarit -haku Oulun yliopisto | Fysiikan seminaarit
... indicate that some of the complex physics of galaxy formation are not yet fully understood? 17.02.2011 MSc. Timo Virtanen (University of Oulu) Quasiparticle dynamics in Fermi liquids Abstract: Fermi liquid theory is a fundamental theory of interacting many body systems, a standard against which othe ...
... indicate that some of the complex physics of galaxy formation are not yet fully understood? 17.02.2011 MSc. Timo Virtanen (University of Oulu) Quasiparticle dynamics in Fermi liquids Abstract: Fermi liquid theory is a fundamental theory of interacting many body systems, a standard against which othe ...
Quantum Theory of the Coherently Pumped Micromaser
... The interaction of the maser field and the passing atoms is described by the Jaynes-Cummings Hamiltonian, the most commonly used interaction Hamiltonian of theoretical quantum optics. The microwave cavities used in today’s experiments have long decay times (approx. 0.3 s), therefore effects occur ...
... The interaction of the maser field and the passing atoms is described by the Jaynes-Cummings Hamiltonian, the most commonly used interaction Hamiltonian of theoretical quantum optics. The microwave cavities used in today’s experiments have long decay times (approx. 0.3 s), therefore effects occur ...
Randomness in (Quantum) Information Processing
... The second, and equally important, reason to study quantum information processing is that it is a generalization of classical information processing. It addresses all problems of information processing, but the main difference lies in the model of information, communication and computation. The quan ...
... The second, and equally important, reason to study quantum information processing is that it is a generalization of classical information processing. It addresses all problems of information processing, but the main difference lies in the model of information, communication and computation. The quan ...
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.