The Experts below are selected from a list of 5538 Experts worldwide ranked by ideXlab platform
Tadao Nakamura - One of the best experts on this subject based on the ideXlab platform.
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No-Cloning Theorem, Kochen-Specker Theorem, and Quantum Measurement Theories
International Journal of Theoretical Physics, 2019Co-Authors: Koji Nagata, Tadao Nakamura, Ahmed Farouk, Ngoc DiepAbstract:The usual no-cloning theorem implies that two quantum states are identical or orthogonal if we allow a cloning to be on the two quantum states. Here, we investigate a relation between the no-cloning theorem and the Projective Measurement theory that the results of Measurements are either + 1 or − 1. We introduce the Kochen-Specker (KS) theorem with the Projective Measurement theory. We result in the fact that the two quantum states under consideration cannot be orthogonal if we avoid the KS contradiction. Thus the no-cloning theorem implies that the two quantum states under consideration are identical in that case. It turns out that the KS theorem with the Projective Measurement theory says a new version of the no-cloning theorem. Next, we investigate a relation between the no-cloning theorem and the Measurement theory based on the truth values that the results of Measurements are either + 1 or 0. We return to the usual no-cloning theorem that the two quantum states are identical or orthogonal in the case.
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No-Cloning Theorem, Kochen-Specker Theorem, and Quantum Measurement Theories
viXra, 2019Co-Authors: Koji Nagata, Tadao Nakamura, Ahmed Farouk, Ngoc DiepAbstract:The usual no-cloning theorem implies that two quantum states are identical or orthogonal if we allow a cloning to be on the two quantum states. Here, we investigate a relation between the no-cloning theorem and the Projective Measurement theory that the results of Measurements are either $+1$ or $-1$. We introduce the Kochen-Specker (KS) theorem with the Projective Measurement theory. We result in the fact that the two quantum states under consideration cannot be orthogonal if we avoid the KS contradiction. Thus the no-cloning theorem implies that the two quantum states under consideration are identical in the case. It turns out that the KS theorem with the Projective Measurement theory says a new version of the no-cloning theorem. Next, we investigate a relation between the no-cloning theorem and the Measurement theory based on the truth values that the results of Measurements are either $+1$ or $0$. We return to the usual no-cloning theorem that the two quantum states are identical or orthogonal in the case.
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Kochen-Specker Theorem and the Two Quantum Measurement Theories
Journal of Mathematics and Physics, 2018Co-Authors: Koji Nagata, Tadao Nakamura, Han Geurdes, Josep Batle, Soliman Abdalla, Ahmed FaroukAbstract:We consider the two quantum Measurement theories for measuring a single Pauli observable. We assume also the existence of a classical probability space for the two Measurement theories. We cannot avoid the Kochen-Specker (KS) contradiction when we measure the Pauli observable by using the Projective Measurement theory if we introduce a classical probability space. The results of Measurement are either $+1$ or $-1$ (in $\hbar/2$ unit) when we consider a spin-1/2 system. The Projective Measurement theory does not accept a classical probability space when we measure the Pauli observable. We propose a new Measurement theory based on the truth values, i.e., the truth T (1) for true and the falsity F (0) for false. The results of Measurement are either $+1$ or 0 (in $\hbar/2$ unit). We avoid the KS contradiction when we measure the Pauli observable by using the new Measurement theory if we introduce a classical probability space. The new Measurement theory accepts a classical probability space when we measure the Pauli observable.
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Boolean approach to dichotomic quantum Measurement theories
Journal of the Korean Physical Society, 2017Co-Authors: Koji Nagata, Tadao Nakamura, Josep Batle, Soliman Abdalla, Ahmed FaroukAbstract:Recently, a new Measurement theory based on truth values was proposed by Nagata and Nakamura [Int. J. Theor. Phys. 55, 3616 (2016)], that is, a theory where the results of Measurements are either 0 or 1. The standard Measurement theory accepts a hidden variable model for a single Pauli observable. Hence, we can introduce a classical probability space for the Measurement theory in this particular case. Additionally, we discuss in the present contribution the fact that Projective Measurement theories (the results of which are either +1 or −1) imply the Bell, Kochen, and Specker (BKS) paradox for a single Pauli observable. To justify our assertion, we present the BKS theorem in almost all the two-dimensional states by using a Projective Measurement theory. As an example, we present the BKS theorem in two-dimensions with white noise. Our discussion provides new insight into the quantum Measurement problem by using this Measurement theory based on the truth values.
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Does a classical probability space for two-dimensional quantum Measurement theory exist?
viXra, 2016Co-Authors: Koji Nagata, Tadao NakamuraAbstract:Recently, a new Measurement theory based on the truth values is proposed \cite{NN1}. The results of Measurements are either 0 or 1. The Measurement theory accepts a hidden variables model for a single Pauli observable. Therefore we can introduce a classical probability space for the Measurement theory in this case. On the other hand, we discuss the fact that the Projective Measurement theory (the results of Measurements are either $+1$ or $-1$) does not meet a hidden variables model for a single Pauli observable. Hence we cannot introduce a classical probability space for the Projective Measurement theory in this case. Our discussion provides new insight to formulate quantum Measurement theory, by using the Measurement theory based on the truth values.
Koji Nagata - One of the best experts on this subject based on the ideXlab platform.
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No-Cloning Theorem, Kochen-Specker Theorem, and Quantum Measurement Theories
International Journal of Theoretical Physics, 2019Co-Authors: Koji Nagata, Tadao Nakamura, Ahmed Farouk, Ngoc DiepAbstract:The usual no-cloning theorem implies that two quantum states are identical or orthogonal if we allow a cloning to be on the two quantum states. Here, we investigate a relation between the no-cloning theorem and the Projective Measurement theory that the results of Measurements are either + 1 or − 1. We introduce the Kochen-Specker (KS) theorem with the Projective Measurement theory. We result in the fact that the two quantum states under consideration cannot be orthogonal if we avoid the KS contradiction. Thus the no-cloning theorem implies that the two quantum states under consideration are identical in that case. It turns out that the KS theorem with the Projective Measurement theory says a new version of the no-cloning theorem. Next, we investigate a relation between the no-cloning theorem and the Measurement theory based on the truth values that the results of Measurements are either + 1 or 0. We return to the usual no-cloning theorem that the two quantum states are identical or orthogonal in the case.
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No-Cloning Theorem, Kochen-Specker Theorem, and Quantum Measurement Theories
viXra, 2019Co-Authors: Koji Nagata, Tadao Nakamura, Ahmed Farouk, Ngoc DiepAbstract:The usual no-cloning theorem implies that two quantum states are identical or orthogonal if we allow a cloning to be on the two quantum states. Here, we investigate a relation between the no-cloning theorem and the Projective Measurement theory that the results of Measurements are either $+1$ or $-1$. We introduce the Kochen-Specker (KS) theorem with the Projective Measurement theory. We result in the fact that the two quantum states under consideration cannot be orthogonal if we avoid the KS contradiction. Thus the no-cloning theorem implies that the two quantum states under consideration are identical in the case. It turns out that the KS theorem with the Projective Measurement theory says a new version of the no-cloning theorem. Next, we investigate a relation between the no-cloning theorem and the Measurement theory based on the truth values that the results of Measurements are either $+1$ or $0$. We return to the usual no-cloning theorem that the two quantum states are identical or orthogonal in the case.
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Kochen-Specker Theorem and the Two Quantum Measurement Theories
Journal of Mathematics and Physics, 2018Co-Authors: Koji Nagata, Tadao Nakamura, Han Geurdes, Josep Batle, Soliman Abdalla, Ahmed FaroukAbstract:We consider the two quantum Measurement theories for measuring a single Pauli observable. We assume also the existence of a classical probability space for the two Measurement theories. We cannot avoid the Kochen-Specker (KS) contradiction when we measure the Pauli observable by using the Projective Measurement theory if we introduce a classical probability space. The results of Measurement are either $+1$ or $-1$ (in $\hbar/2$ unit) when we consider a spin-1/2 system. The Projective Measurement theory does not accept a classical probability space when we measure the Pauli observable. We propose a new Measurement theory based on the truth values, i.e., the truth T (1) for true and the falsity F (0) for false. The results of Measurement are either $+1$ or 0 (in $\hbar/2$ unit). We avoid the KS contradiction when we measure the Pauli observable by using the new Measurement theory if we introduce a classical probability space. The new Measurement theory accepts a classical probability space when we measure the Pauli observable.
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Boolean approach to dichotomic quantum Measurement theories
Journal of the Korean Physical Society, 2017Co-Authors: Koji Nagata, Tadao Nakamura, Josep Batle, Soliman Abdalla, Ahmed FaroukAbstract:Recently, a new Measurement theory based on truth values was proposed by Nagata and Nakamura [Int. J. Theor. Phys. 55, 3616 (2016)], that is, a theory where the results of Measurements are either 0 or 1. The standard Measurement theory accepts a hidden variable model for a single Pauli observable. Hence, we can introduce a classical probability space for the Measurement theory in this particular case. Additionally, we discuss in the present contribution the fact that Projective Measurement theories (the results of which are either +1 or −1) imply the Bell, Kochen, and Specker (BKS) paradox for a single Pauli observable. To justify our assertion, we present the BKS theorem in almost all the two-dimensional states by using a Projective Measurement theory. As an example, we present the BKS theorem in two-dimensions with white noise. Our discussion provides new insight into the quantum Measurement problem by using this Measurement theory based on the truth values.
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Does a classical probability space for two-dimensional quantum Measurement theory exist?
viXra, 2016Co-Authors: Koji Nagata, Tadao NakamuraAbstract:Recently, a new Measurement theory based on the truth values is proposed \cite{NN1}. The results of Measurements are either 0 or 1. The Measurement theory accepts a hidden variables model for a single Pauli observable. Therefore we can introduce a classical probability space for the Measurement theory in this case. On the other hand, we discuss the fact that the Projective Measurement theory (the results of Measurements are either $+1$ or $-1$) does not meet a hidden variables model for a single Pauli observable. Hence we cannot introduce a classical probability space for the Projective Measurement theory in this case. Our discussion provides new insight to formulate quantum Measurement theory, by using the Measurement theory based on the truth values.
T P Orlando - One of the best experts on this subject based on the ideXlab platform.
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Projective Measurement scheme for solid state qubits
Physical Review B, 2003Co-Authors: Lin Tian, Seth Lloyd, T P OrlandoAbstract:We present an effective Measurement scheme for the solid-state qubits, which does not introduce extra decoherence to the qubits until the Measurement is switched on by a resonant pulse. The resonant pulse then maximally entangles the qubit with the detector. The scheme has the feature of being Projective, noiseless, and switchable. This method is illustrated on the superconducting persistent-current qubit, but can be applied to the Measurement of a wide variety of solid-state qubits, the direct detection of the electromagnetic signals of which gives poor resolution of the qubit states.
Lin Tian - One of the best experts on this subject based on the ideXlab platform.
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Projective Measurement scheme for solid state qubits
Physical Review B, 2003Co-Authors: Lin Tian, Seth Lloyd, T P OrlandoAbstract:We present an effective Measurement scheme for the solid-state qubits, which does not introduce extra decoherence to the qubits until the Measurement is switched on by a resonant pulse. The resonant pulse then maximally entangles the qubit with the detector. The scheme has the feature of being Projective, noiseless, and switchable. This method is illustrated on the superconducting persistent-current qubit, but can be applied to the Measurement of a wide variety of solid-state qubits, the direct detection of the electromagnetic signals of which gives poor resolution of the qubit states.
Mio Murao - One of the best experts on this subject based on the ideXlab platform.
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Projective Measurement of energy on an ensemble of qubits with unknown frequencies
Physical Review A, 2017Co-Authors: Yuichiro Matsuzaki, Shojun Nakayama, Akihito Soeda, Shiro Saito, Mio MuraoAbstract:In Projective Measurements of energy, a target system is projected to an eigenstate of the system Hamiltonian and the Measurement outcomes provide the information of corresponding eigenenergies. Recently, it has been shown that such a Measurement can be, in principle, realized without detailed knowledge of the Hamiltonian by using probe qubits. However, in this approach, the size of the dimension for the probe increases as we increase the dimension of the target system; also, individual addressability of every qubit is required, which may not be possible for many experimental settings involving large systems. Here, we show that a single probe qubit is sufficient to perform such a Projective Measurement of energy if the target system is composed of noninteracting qubits whose resonant frequencies are unknown. Moreover, our scheme requires only global manipulations where every qubit is subjected to the same control fields. These results indicate the feasibility of our energy-projection protocols.
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Quantum algorithm for universal implementation of the Projective Measurement of energy.
Physical review letters, 2015Co-Authors: Shojun Nakayama, Akihito Soeda, Mio MuraoAbstract:A Projective Measurement of energy (PME) on a quantum system is a quantum Measurement determined by the Hamiltonian of the system. PME protocols exist when the Hamiltonian is given in advance. Unknown Hamiltonians can be identified by quantum tomography, but the time cost to achieve a given accuracy increases exponentially with the size of the quantum system. In this Letter, we improve the time cost by adapting quantum phase estimation, an algorithm designed for computational problems, to Measurements on physical systems. We present a PME protocol without quantum tomography for Hamiltonians whose dimension and energy scale are given but which are otherwise unknown. Our protocol implements a PME to arbitrary accuracy without any dimension dependence on its time cost. We also show that another computational quantum algorithm may be used for efficient estimation of the energy scale. These algorithms show that computational quantum algorithms, with suitable modifications, have applications beyond their original context.
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Universal implementation of Projective Measurement of energy
arXiv: Quantum Physics, 2013Co-Authors: Shojun Nakayama, Akihito Soeda, Mio MuraoAbstract:We present a scheme to asymptotically implement a Projective Measurement in the energy eigenbasis on a finite dimensional system driven by an unknown Hamiltonian $H$ based on the quantum phase estimation algorithm. Our scheme also provides an outcome associated with an energy eigenvalue of $H$. Two new algorithms are introduced to apply the quantum phase estimation algorithms for unknown Hamiltonian systems. One is for asymptotically but universally implementing a controlled unitary operation $C_{U(t)}$ of a unitary operation $U(t)=e^{-iHt}$ up to the global phase of $U(t)$ for an unknown Hamiltonian $H$. This algorithm utilizes random unitary operations achieve a decoupling effect. The other is an algorithm for evaluating the absolute value of the trace of $U(t)$ without using $C_{U(t)}$ required to run the first algorithm. We analyze the accuracy and the running time of our scheme and show that the running time of our scheme is independent of the dimension of the system for a given accuracy.