Okinawa Institute of Science and Technology (OIST)
Talks by Philipp Hoehn
(Quantum) frame covariance: from foundations via gauge theories to gravity
Philipp Hoehn
Okinawa Institute of Science and Technology (OIST)
I will sketch how the perspectiveneutral approach to (quantum) frame covariance brings together some recent developments on dynamical reference frames in quantum foundations, gauge theories and gravity. The survey will touch on spatial frames, quantum clocks and the problem of time, edge modes, and the relativity of subsystems.
The trinity of relational quantum dynamics
Philipp Hoehn
Okinawa Institute of Science and Technology (OIST)
In order to solve the problem of time in quantum gravity, various approaches to a relational quantum dynamics have been proposed. In this talk, I will exploit quantum reduction maps to illustrate a previously unknown equivalence between three of the wellknown ones: (1) relational observables in the clockneutral picture of Dirac quantization, (2) Page and Wootters’ (PW) Schrödinger picture formalism, and (3) the relational Heisenberg picture obtained via symmetry reduction. Constituting three faces of the same dynamics, we call this equivalence the trinity.
Quantum reference systems: Where foundations meets gravity
Philipp Hoehn
Okinawa Institute of Science and Technology (OIST)
Quantum foundations and (quantum) gravity are usually considered independently. However, I will demonstrate by means of quantum reference systems how tools and perspectives from quantum gravity can help to solve problems in quantum foundations and, conversely, how quantum foundation perspectives can be useful to constrain spacetime structures.
First, I will show how one can derive transformations between quantum reference frames from a gravity inspired symmetry (essentially Mach’s) principle.
Dirac Observables in Chaotic Systems
Philipp Hoehn
Okinawa Institute of Science and Technology (OIST)
Information and the architecture of quantum theory
Philipp Hoehn
Okinawa Institute of Science and Technology (OIST)
I will argue that, apart from their ever growing number of applications to physics, information theoretic concepts also offer a novel perspective on the physical content and architecture of quantum theory and spacetime. As a concrete example, I will discuss how one can derive and understand the formalism of qubit quantum theory by focusing only on what an observer can say about a system and imposing a few simple rules on the observer’s acquisition of information.
Quantum theory from rules on information acquisition
Philipp Hoehn
Okinawa Institute of Science and Technology (OIST)
The last decade has seen a wave of characterizations of quantum theory using the formalism of generalized probability theory.
Elements of Quantum Theory from limited Information and complementarity
Philipp Hoehn
Okinawa Institute of Science and Technology (OIST)
Discrete Approaches  2

Aaron Trout Chatham University

Philipp Hoehn Okinawa Institute of Science and Technology (OIST)
Canonical Time Evolution in Simplicial Gravity
Philipp Hoehn
Okinawa Institute of Science and Technology (OIST)