Quantum theory describes reality in terms of superpositions of seemingly contradictory facts, which then seem to arbitrarily `collapse' to a single objective truth when observed. In this project, in collaboration with TU Wien, we address one of Physics' long-standing open questions: how such a collapse appears to occur, resulting in an objective outcome.
Despite quantum theory's robust experimental and technological success for almost a century, the question of what constitutes an observation, who counts as an observer, and how the world becomes objective, remain open, preventing us from understanding what the theory implies about objective reality, and our place in it as observers.
This project will boldly address these issues using methods from the field of quantum thermodynamics to develop a novel, dynamical model of the measurement process. Based on this, we will obtain precise mathematical criteria for what constitutes a measurement, and a full accounting of the thermodynamic resources involved. From the beginning, we will work with two experimental groups, each international leaders in their field, to produce proposals for testing our model in the laboratory. The results will be communicated via publications in high-profile scientific journals, presented at international conferences, and disseminated in popular science media. We will also organize a conference aimed at bringing the quantum foundations and quantum thermodynamics communities together, to foster further fruitful research in the application of the latter field to problems in the former.
In addition to advancing the debate about how quantum theory relates to our experience of the world, our results will provide fertile ground for the study of quantum engines (such as 'quantum measurement' engines) and measurement-based quantum computation, as well as potential resolutions of some of the paradoxes that have plagued quantum theory since its early days.
