13,588 research outputs found
Hierarchy in temporal quantum correlations
Einstein-Podolsky-Rosen (EPR) steering is an intermediate quantum correlation
that lies in between entanglement and Bell non-locality. Its temporal analogue,
temporal steering, has recently been shown to have applications in quantum
information and open quantum systems. Here, we show that there exists a
hierarchy among the three temporal quantum correlations: temporal
inseparability, temporal steering, and macrorealism. Given that the temporal
inseparability can be used to define a measure of quantum causality, similarly
the quantification of temporal steering can be viewed as a weaker measure of
direct cause and can be used to distinguish between direct cause and common
cause in a quantum network.Comment: 10 pages, 3 figure
Einstein-Podolsky-Rosen steering: Its geometric quantification and witness
We propose a measure of quantum steerability, namely a convex steering
monotone, based on the trace distance between a given assemblage and its
corresponding closest assemblage admitting a local-hidden-state (LHS) model. We
provide methods to estimate such a quantity, via lower and upper bounds, based
on semidefinite programming. One of these upper bounds has a clear geometrical
interpretation as a linear function of rescaled Euclidean distances in the
Bloch sphere between the normalized quantum states of: (i) a given assemblage
and (ii) an LHS assemblage. For a qubit-qubit quantum state, the above ideas
also allow us to visualize various steerability properties of the state in the
Bloch sphere via the so-called LHS surface. In particular, some steerability
properties can be obtained by comparing such an LHS surface with a
corresponding quantum steering ellipsoid. Thus, we propose a witness of
steerability corresponding to the difference of the volumes enclosed by these
two surfaces. This witness (which reveals the steerability of a quantum state)
enables finding an optimal measurement basis, which can then be used to
determine the proposed steering monotone (which describes the steerability of
an assemblage) optimized over all mutually-unbiased bases
Recommended from our members
T Oligo-Primed Polymerase Chain Reaction (TOP-PCR): A Robust Method for the Amplification of Minute DNA Fragments in Body Fluids.
Body fluid DNA sequencing is a powerful noninvasive approach for the diagnosis of genetic defects, infectious agents and diseases. The success relies on the quantity and quality of the DNA samples. However, numerous clinical samples are either at low quantity or of poor quality due to various reasons. To overcome these problems, we have developed T oligo-primed polymerase chain reaction (TOP-PCR) for full-length nonselective amplification of minute quantity of DNA fragments. TOP-PCR adopts homogeneous "half adaptor" (HA), generated by annealing P oligo (carrying a phosphate group at the 5' end) and T oligo (carrying a T-tail at the 3' end), for efficient ligation to target DNA and subsequent PCR amplification primed by the T oligo alone. Using DNA samples from body fluids, we demonstrate that TOP-PCR recovers minute DNA fragments and maintains the DNA size profile, while enhancing the major molecular populations. Our results also showed that TOP-PCR is a superior method for detecting apoptosis and outperforms the method adopted by Illumina for DNA amplification
The Number of Alternative Products and the Information about it on the Online Shop
As the Internet can aggregate and distribute a great amount of information to users, providing numerous products for consumers has been recognized as a major advantage of electronic commerce. Causing by the problem of information overload, however, consumers facing many alternatives on the online shop may feel hard to decide which one they prefer. Based on the theory of decision style and prospect theory, this study explores if too many products sold on the online shop will reduce consumers’ subjective status toward their buying decision. A 3×3 between subjects experiment was conducted and showed that the buyers’ decision style, the quantity of alternative products and the information about it will affect consumers’ subjective status. These results suggest that we should consider the role of electronic intermediaries more carefully, and further examine the theory of information overload and the need for information literacy to prepare for the future
- …