Zenith Grant Awardee

Giulio Chiribella

Tsinghua University

Project Title

The fundamental principles of information-dynamics

Project Summary

Quantum mechanics is weird, everyone would say, and it is not surprising that much work is being done in providing plausible explanations of its weirdness. Recently, many exciting progresses came through an information-theoretic approach inspired by quantum information. However, most works focused on explaining the quantum rules for predicting the random outcomes of experiments, while the rules that govern the evolution of microscopic systems in time still remain mysterious. Think of the Schroedinger equation, which was discovered by guesswork using an adventurous analogy between particle mechanics and optics. What is the fundamental meaning of this equation, that describes so well the atoms and molecules constituting our world? Is there a fundamental relation between this particular type of evolution and the speed-up that quantum mechanics offers in doing calculations? In this project we will seek for a fundamental understanding of quantum dynamics from basic principles inspired by information processing and computation. At the same time, we want to question the very paradigm of dynamics, namely the idea that the state of a system evolves in time through a sequence of steps, exploring the possibility that time evolution could be the result of a more fundamental composition of systems in spacetime.

Technical Abstract

Over the past decade, the information-theoretic approach to the foundations of quantum mechanics has attracted an enormous attention, leading to the formulation of new physical principles and to new ways to axiomatize quantum theory. However, most investigations conducted so far focused on kinematical aspects, and very little is known about the information-theoretic characterization of quantum dynamics. If quantum theory can be recast as a new form of information theory, which kind of information dynamics corresponds to the Schroedinger equation and its relativistic versions? Here we will address the question, searching for fundamental links between the form of the quantum dynamical laws and fundamental features about information gathering and computation, such as the quantum speed limit, the quadratic speed-up of quantum metrology, and the speed-up of quantum algorithms. In addition, we will explore possible approaches to go beyond the paradigm of dynamics, trying to replace the evolution of physical states in time with a more general notion of composition in spacetime.