Coherent information

About: Coherent information is a research topic. Over the lifetime, 1225 publications have been published within this topic receiving 46672 citations.

From Primeval Chaos to Infinite Intelligence: On Information As a Dimension and on Entropy As a Field of Force

Abstract: From pebble tools to computers the dimension of information entropy as a field of force quantum physics - the dimension of information and the field of entropy evolution - is it by chance or by necessity? survival and ethics the information dimension in retrospect postscript and epilogue. Appendix: from the lower part of Tiamat to the Law of D'arcy.

Quantum observable

Abstract: Over the last decade, many researchers have studied the implementation of quantum systems and the states of the quantum systems. Most of the focus has been on the quantum states strategy. Researchers have found it to be more advanced than classical strategies. Complementary quantum Observables interaction and information are the most important features that are refereed by Observables. This shows us how uniquely these features can define a packet of information in mathematical terms as a state. Also, it provides technological information that indeed captures the properties of quantum systems. In this paper, we demonstrate how to implement certain logical methods in quantum computing to obtain more accurate information than classical computing systems provide. This new methodology can make the computation more efficient. First, we examine the photons and consider the various spin states, and then we consider the direction of the spinning photons to handle more information. Next, we use the unique property of photons to behave both as a wave and a particle and exploit it by passing the photon through mirrors and beam splitters to demonstrate and achieve results that are not possible in the classical world.

Quantum Observer, Information Theory and Kolmogorov Complexity

Abstract: The theory itself does not tell us which properties are sufficient for a system to count as a quantum mechanical observer. Thus, it remains an open problem to find a suitable language for characterizing observation. We propose an information-theoretic definition of observer, leading to a mathematical criterion of objectivity using the formalism of Kolmogorov complexity. We also suggest an experimental test of the hypothesis that any system, even much smaller than a human being, can be a quantum mechanical observer.

Second-order coding rates for entanglement-assisted communication

Abstract: The entanglement-assisted capacity of a quantum channel is known to provide the formal quantum generalization of Shannon's classical channel capacity theorem, in the sense that it admits a single-letter characterization in terms of the quantum mutual information and does not increase in the presence of a noiseless quantum feedback channel from receiver to sender. In this work, we investigate second-order asymptotics of the entanglement-assisted communication task. That is, we consider how quickly the rates of entanglement-assisted codes converge to the entanglement-assisted capacity of a channel as a function of the number of channel uses and the error tolerance. We define a quantum generalization of the mutual information variance of a channel in the entanglement-assisted setting. For covariant channels, we show that this quantity is equal to the channel dispersion, and characterizes the convergence towards the entanglement-assisted capacity when the number of channel uses increases. More generally, we prove that the Gaussian approximation for a second-order coding rate is achievable for all quantum channels.

Noise-induced Renyi entropy flow of a quantum heat engine

Abstract: Entropy is one of the central quantities in thermodynamics, whose flow between two systems determines the statistics of energy transfers. In quantum systems entropy is non-linear in density matrix whose time evolution is cumbersome. Using recent developments in the Keldysh formalism for the evolution of nonlinear quantum information measures (Phys. Rev. B 91, 174307 (2015)), we study the flow of von Neumann and Renyi entropies in a generic four-level quantum system that is weakly coupled to equilibrium heat engines. We show that noise-induced coherence has significant influence on the entropy flow of the quantum heat engine. We determine analytical optimization of couplings for the purpose of designing optimal artificial energy transfer systems.