Coherent information

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

Quantum Theory as Efficient Representation of Probabilistic Information

Abstract: Quantum experiments yield random data. We show that the most efficient way to store this empirical information by a finite number of bits is by means of the vector of square roots of observed relative frequencies. This vector has the unique property that its dispersion becomes invariant of the underlying probabilities, and therefore invariant of the physical parameters. This also extends to the complex square roots, and it remains true under a unitary transformation. This reveals quantum theory as a theory for making predictions which are as accurate as the input information, without any statistical loss. Our analysis also suggests that from the point of view of information a slightly more accurate theory than quantum theory should be possible.

Change in the quantum information difference during evoluton of nonextensive systems in the space of control parameters

Abstract: An information-theoretic description of induced transitions between stationary states in the space of control parameters is given for nonextensive self-organized systems. The S- and I-theorems on changes in nonadditive entropy and information difference measures are proved in the general form when the effective Hamiltonian function is unknown. The statistical method is used to derive the q-entropy and q-information difference depending on the distribution seminorm.

Quantum information algorithms – new solutions for known problems

Abstract: The use of quantum information theory and the understanding of the information it conveys seems to be one of the most challenging and rapidly developing research areas at present In this article we concentrate on the implications quantum information theory might have on rather classical problems that are rephrased and embedded into a quantum space Especially, the area of signal and image processing seems to be well suited for this approach We give an example of mapping colour spaces into the quantum space and show that the resulting quantum systems are highly beneficial when dealing with this kind of data

Minimum uncertainty solutions for partially coherent fields and quantum mixed states

Abstract: A general prescription is given for finding uncertainty relations that dictate the lower bounds on the measures of spread corresponding to two different representations of a partially coherent wave field or mixed quantum state, for a given measure of overall coherence or purity. In particular it is shown that the coherent modes of the fields/states that achieve the lower bounds are independent of the measure of purity being used, and that this measure determines only the amount in which these modes contribute. Our results are important in the design of optical systems with partially coherent light and in quantum mixed states, for which maximal joint localization is desired. These ideas are illustrated for the case of optical beams, pulses propagating in dispersive media and quantum phase.