Representation of Joint Measurement in Quantum Mechanics. A Refutation of Quantum Teleportation
Guillaume Adenier
备注：
RevTex4, 9 pages, no figures. Section 4 on Quantum Teleportation expanded and explicited. Minor modifications in other sections. New references added. Comments are welcome
An inconsistency is pointed out within Quantum Mechanics as soon as successive joint measurements are involved on entangled states. The resolution of the inconsistency leads to a refutation of the use of entangled states as eigenvectors. Hence, the concept of quantum teleportation, which is based on the use of such entangled states--the Bell states--as eigenvectors, is demonstrated to be irrelevant to Quantum Mechanics.
Physicists describe nature using mathematics as the natural language, and for quantum mechanics, it prefers to use complex numbers. However, whether complex numbers are really necessary for the theory has been debated ever since its birth. Recently, it has been shown that a three-party correlation created in entanglement swapping scenarios comprising independent states and measurements cannot be reproduced using only real numbers. Previous experiments have conceptually supported the predication, yet not satisfying the independent state preparations and measurements simultaneously. Here, we imp…
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Universal quantum error-correction requires the ability of manipulating entanglement of five or more particles. Although entanglement of three or four particles has been experimentally demonstrated and used to obtain the extreme contradiction between quantum mechanics and local realism, the realization of five-particle entanglement remains an experimental challenge. Meanwhile, a crucial experimental challenge in multi-party quantum communication and computation is the so-called open-destination teleportation. During open-destination teleportation, an unknown quantum state of a single particle …
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Hidden-variable models aim to reproduce the results of quantum theory and to satisfy our classical intuition. Their refutation is usually based on deriving predictions that are different from those of quantum mechanics. Here instead we study the mutual compatibility of apparently reasonable classical assumptions. We analyze a version of the delayed-choice experiment which ostensibly combines determinism, independence of hidden variables on the conducted experiments, and wave-particle objectivity (the assertion that quantum systems are, at any moment, either particles or waves, but not both). T…
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This is a collection of references (papers, books, preprints, book reviews, Ph. D. thesis, patents, web sites, etc.), sorted alphabetically and (some of them) classified by subject, on foundations of quantum mechanics and quantum information. Specifically, it covers hidden variables (``no-go'' theorems, experiments), interpretations of quantum mechanics, entanglement, quantum effects (quantum Zeno effect, quantum erasure, ``interaction-free'' measurements, quantum ``non-demolition'' measurements), quantum information (cryptography, cloning, dense coding, teleportation), and quantum computation…
Teleportation is a fundamental concept of quantum mechanics with an important application in extending the range of quantum communication channels via quantum relay nodes. To be compatible with real-world technology such as secure quantum key distribution over fibre networks, such a relay node must operate at GHz clock rates and accept time-bin encoded qubits in the low-loss telecom band around 1550 nm. Here, we show that InAs/InP droplet epitaxy quantum dots with their sub-Poissonian emission near 1550 nm are ideally suited for the realisation of this technology. To create the necessary on-de…
Teleportation is the most widely discussed application of the basic principles of quantum mechanics. Fundamentally, this process describes the transmission of information, which involves transport of neither matter nor energy. The implicit assumption, however, is that this scheme is of inherently nonlocal nature, and therefore exclusive to quantum systems. Here, we show that the concept can be readily generalized beyond the quantum realm. We present an optical implementation of the teleportation protocol solely based on classical entanglement between spatial and modal degrees of freedom, entir…
Quantum Teleportation is the key communication functionality of the Quantum Internet, allowing the "transmission' of qubits without either the physical transfer of the particle storing the qubit or the violation of the quantum mechanical principles. Quantum teleportation is facilitated by the action of quantum entanglement, a somewhat counter-intuitive physical phenomenon with no direct counterpart in the classical word. As a consequence, the very concept of the classical communication system model has to be redesigned to account for the peculiarities of quantum teleportation. This re-design i…
The question whether quantum mechanics is complete and the nature of the transition between quantum mechanics and classical mechanics have intrigued physicists for decades. There have been many experimental breakthroughs in creating larger and larger quantum superposition and entangled states since Erwin Schrödinger proposed his famous thought experiment of putting a cat in a superposition of both alive and dead states in 1935. Remarkably, recent developments in quantum optomechanics and electromechanics may lead to the realization of quantum superposition of living microbes soon. Recent evide…
We address fundamental limitations of quantum teleportation -- the process of transferring quantum information using classical communication and preshared entanglement. We develop a new teleportation protocol based upon the idea of using ancillary entanglement catalytically, i.e. without depleting it. This protocol is then used to show that catalytic entanglement allows for a noiseless quantum channel to be simulated with a quality that could never be achieved using only entanglement from the shared state, even for catalysts with a small dimension. On the one hand, this allows for a more faith…
Quantum teleportation, the faithful transfer of an unknown input state onto a remote quantum system, is a key component in long distance quantum communication protocols and distributed quantum computing. At the same time, high frequency nano-optomechanical systems hold great promise as nodes in a future quantum network, operating on-chip at low-loss optical telecom wavelengths with long mechanical lifetimes. Recent demonstrations include entanglement between two resonators, a quantum memory and microwave to optics transduction. Despite these successes, quantum teleportation of an optical input…
Although nondemolition, reliable, and instantaneous quantum measurements of some nonlocal variables are impossible, demolition reliable instantaneous measurements are possible for all variables. It is shown that this is correct also in the framework of the time-symmetric quantum formalism, i.e. nonlocal variables of composite quantum systems with quantum states evolving both forward and backward in time are measurable in a demolition way. The result follows from the possibility to reverse with certainty the time direction of a backward evolving quantum state. Demolition measurements of nonloca…
Quantum Port: Gamification of quantum teleportation for public engagement
Multimedia University（多媒体大学）；Institute for Mathematical Research (INSPEM), Universiti Putra Malaysia (UPM)（马来西亚博特拉大学数学研究所）；AR Display Resources（AR显示资源）；SEGi College Subang Jaya（双溪毛糯世纪学院）；Department of Physics, Faculty of Science, Universiti Putra Malaysia (UPM)（马来西亚博特拉大学理学院物理系）
We show that the use of real measuring rods in quantum mechanics places a fundamental gravitational limit to the level of entanglement that one can ultimately achieve in quantum systems. The result can be seen as a direct consequence of the fundamental gravitational limitations in the measurements of length and time in realistic physical systems. The effect may have implications for long distance teleportation and the measurement problem in quantum mechanics.
Quantum mechanics has many counter-intuitive consequences which contradict our intuition which is based on classical physics. Here we discuss a special aspect of quantum mechanics, namely the possibility of entanglement between two or more particles. We will establish the basic properties of entanglement using quantum state teleportation. These principles will then allow us to formulate quantitative measures of entanglement. Finally we will show that the same general principles can also be used to prove seemingly difficult questions regarding entanglement dynamics very easily. This will be use…
