Algorithmic complexity of quantum capacity

Recently the theory of communication developed by Shannon has been extended to the quantum realm by exploiting the rules of quantum theory. This latter stems on complex vector spaces. However complex (as well as real) numbers are just idealizations and they are not available in practice where we can only deal with rational numbers. This fact naturally leads to the question of whether the developed notions of capacities for quantum channels truly catch their ability to transmit information. Here we answer this question for the quantum capacity. To this end we resort to the notion of semi-computability in order to approximately (by rational numbers) describe quantum states and quantum channel maps. Then we introduce algorithmic entropies (like algorithmic quantum coherent information) and derive relevant properties for them. Finally we define algorithmic quantum capacity and prove that it equals the standard one

Modeling of Traceability Information System for Material Flow Control Data.

This paper focuses on data modeling for traceability of material/work flow in information layer of manufacturing control system. The model is able to trace all associated data throughout the product manufacturing from order to final product. Dynamic data processing of Quality and Purchase activities are considered in data modeling as well as Order and Operation base on lots particulars. The modeling consisted of four steps and integrated as one final model. Entity-Relationships Modeling as data modeling methodology is proposed. The model is reengineered with Toad Data Modeler software in physical modeling step. The developed model promises to handle fundamental issues of a traceability system effectively. It supports for customization and real-time control of material in flow in all levels of manufacturing processes. Through enhanced visibility and dynamic store/retrieval of data, all traceability usages and applications is responded. Designed solution is initially applicable as reference data model in identical lot-base traceability system

Profitable entanglement for channel discrimination

We investigate the usefulness of side entanglement in discriminating between two generic qubit channels and determine exact conditions under which it does enhance (as well as conditions under which it does not) the success probability. This is done in a constructive way by first analyzing the problem for channels that are extremal in the set of completely positive and trace-preserving qubit linear maps and then for channels that are inside such a set

Quantum reading of quantum information

We extend the notion of quantum reading to the case where the information to be retrieved, which is encoded into a set of quantum channels, is of quantum nature. We use two qubit unitaries describing the system environment interaction, with the initial environment state determining the system's input output channel and hence the encoded information. The performance of the most relevant two-qubit unitaries is determined with two different approaches: i) one-shot quantum capacity of the channel arising between environment and system's output; ii) estimation of parameters characterizing the initial quantum state of the environment. The obtained results are mostly in (qualitative) agreement, with some distinguishing features that include the CNOT unitary.Comment: Relations/differences with respect to previous works are better explained, and new references are adde

Comparative study on the antifungal activity of hydroalcoholic extract of Iranian Propolis and <em>Royal jelly </em>against <em>Rhizopus oryzae </em>

Introduction: Mucormycosis is an opportunistic fungal infection. Rhizopus oryzae is major cause of mucormycosis in humans. This disease is the most common form of the acute fungal infection with rapid progress. Iranian Propolis extract and Royal jelly are honey bee products which have been used by human over the past centuries in traditional medicine. In this study the effects of Iranian Propolis and Royal jelly were investigated against Rhizopus oryzae and Candida albicans. Methods: The used method in this study was microdilution. To perform it, the prepared dilutions of Royal jelly and alcoholic extract of Iranian Propolis were added to tubes containing Sabouraud dextrose broth culture media except to control group and then Rhizopus oryzae suspension was added to all microtubes. In the next stage, microtubes were maintained in incubator at 25oC for 48 hours and then 10 ml of the content of each microtube was transferred to Sabouraud dextrose agar media. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of the agents were calculated. Results: In this study, the MIC and MFC of Iranian Propolis alcoholic extract on Rhizopus oryzae were respectively 0.1 and 0.25 mg/ml and the MFC of Royal jelly on Rhizopus oryzae were respectively 100 &plusmn; 34 and 133 &plusmn; 46 mg/ml. Conclusion: The results indicate that Propolis might be used as an ideal combination for the treatment of fungal infections like Rhizopus oryzae. However, clinical studies are needed to confirm the effects of these drugs.</p

Union bound for quantum information processing

In this paper, we prove a quantum union bound that is relevant when performing a sequence of binary-outcome quantum measurements on a quantum state. The quantum union bound proved here involves a tunable parameter that can be optimized, and this tunable parameter plays a similar role to a parameter involved in the Hayashi-Nagaoka inequality [IEEE Trans. Inf. Theory, 49(7):1753 (2003)], used often in quantum information theory when analyzing the error probability of a square-root measurement. An advantage of the proof delivered here is that it is elementary, relying only on basic properties of projectors, the Pythagorean theorem, and the Cauchy--Schwarz inequality. As a non-trivial application of our quantum union bound, we prove that a sequential decoding strategy for classical communication over a quantum channel achieves a lower bound on the channel's second-order coding rate. This demonstrates the advantage of our quantum union bound in the non-asymptotic regime, in which a communication channel is called a finite number of times. We expect that the bound will find a range of applications in quantum communication theory, quantum algorithms, and quantum complexity theory.Comment: v2: 23 pages, includes proof, based on arXiv:1208.1400 and arXiv:1510.04682, for a lower bound on the second-order asymptotics of hypothesis testing for i.i.d. quantum states acting on a separable Hilbert spac

Optimal input states for quantifying the performance of continuous-variable unidirectional and bidirectional teleportation

Continuous-variable (CV) teleportation is a foundational protocol in quantum information science. A number of experiments have been designed to simulate ideal teleportation under realistic conditions. In this paper, we detail an analytical approach for determining optimal input states for quantifying the performance of CV unidirectional and bidirectional teleportation. The metric that we consider for quantifying performance is the energy-constrained channel fidelity between ideal teleportation and its experimental implementation, and along with this, our focus is on determining optimal input states for distinguishing the ideal process from the experimental one. We prove that, under certain energy constraints, the optimal input state in unidirectional, as well as bidirectional, teleportation is a finite entangled superposition of twin-Fock states saturating the energy constraint. Moreover, we also prove that, under the same constraints, the optimal states are unique; that is, there is no other optimal finite entangled superposition of twin-Fock states.Comment: 26 pages, 4 figures, accepted for publication in Physical Review