Information and Interaction

Igor Gurevich

Information is an integral part of the Universe. By its physical essence information is heterogeneity of matter and energy. Therefore information is inseparably connected with matter and energy. The universal measure of information in physical heterogeneity is the Shannon information entropy. An information approach along with a physical one allows to obtain new, sometimes more general data in relation to data obtained on the ground of physical rules only. The results presented in this paper show the effectiveness of informational approach for studying the interactions in the Universe. The paper shows that, along with the physical interactions the gravitational, electromagnetic, strong, weak interactions exists fifth type of fundamental interactions-information interaction, whose magnitude is not dependent on distance. The existence of information interaction is determined by the entanglement of quantum states, of quantum subsystems. The magnitude of information interaction is measured in bits.

Benjamin Piwowarski, Mounia Lalmas

Even the best information retrieval model cannot always identify the most useful answers to a user query. This is in particular the case with web search systems, where it is known that users tend to minimise their effort to access relevant information. It is, however, believed that the interaction between users and a retrieval system, such as a web search engine, can be exploited to provide better answers to users. Interactive Information Retrieval (IR) systems, in which users access information through a series of interactions with the search system, are concerned with building models for IR, where interaction plays a central role. There are many possible interactions between a user and a search system, ranging from query (re)formulation to relevance feedback. However, capturing them within a single framework is difficult and previously proposed approaches have mostly focused on relevance feedback. In this paper, we propose a general framework for interactive IR that is able to capture the full interaction process in a principled way. Our approach relies upon a generalisation of the probability framework of quantum physics, whose strong geometric component can be a key towards a successful interactive IR model.

Aide, Satoru

Emily Kendall, Barbara Šoda, Achim Kempf

Abstract In this work, we investigate the parameters governing the rate at which a quantum channel arises at the onset of an interaction between two systems, A and B . In particular, when system A is pre-entangled with an ancilla, A ~ , we quantify the early-time transmission of pre-existing entanglement by calculating the leading order change in coherent information of the complementary channel ( A → B ′). We show that, when A and B are initially unentangled and B is pure, there is no change in coherent information to first order, while the leading (second) order change is divergent. However, this divergence may be regulated by embedding the conventional notion of coherent information into what we call the family of n -coherent informations, defined using n -Rényi entropies. We find that the rate of change of the n -coherent information at the onset of the interaction is governed by a quantity, which we call the n -exposure, which captures the extent to which the initial coherent information of A with A ~ is exposed to or ‘seen by’ the interaction Hamiltonian between A and B . We give examples in qubit systems and in the light–matter interaction.