# Qubits and Spacetime Unit (Philipp Höhn)

The challenge of quantum gravity is to build a theory valid over all the scales down to the minuscule Planck scale, which explains how the known operational physics of general relativity and quantum (field) theory emerge from it. This deep challenge is the main impetus of the research efforts of the Qubits and Spacetime Unit, which reside at the interface of quantum gravity, quantum information and foundations.

The focus of our research does not lie on approach-specific problems, but on generic challenges, which many approaches to quantum gravity will have to face up to and which have implications and relevance also in other areas of physics. The idea is to develop concepts, tools and methodology, which will be useful for various approaches to quantum gravity and beyond, e.g., in many-body physics and quantum information and foundations.

### Recent overview talks:

- Philipp Höhn, "Perspective-neutral approach to quantum frame covariance", Nov 17 & 30 2020, two-part seminar, Quantum Information Theory Group of
*ETH Zürich*(video of the first talk can be found here, of the second one here). - Philipp Höhn, "Problem of time, relational observables and quantum covariance", Oct 7 2020, inaugural talk of the new international seminar series initiative
*Quantum Gravity Across Approaches*(video can be found here). - Philipp Höhn, "Progress in relational quantum dynamics", Sep 15 2020,
*International LQG Seminar*(video can be found here).

### New articles:

- Josh Kirklin, "Islands and Uhlmann phase: Explicit recovery of classical information from evaporating black holes", https://arxiv.org/abs/2011.07086
- Marius Krumm, Philipp A. Höhn, and Markus P. Müller, "Quantum reference frame transformations as symmetries and the paradox of the third particle", https://arxiv.org/abs/2011.01951
- Philipp A. Höhn, Alexander R. H. Smith, and Maximilian P. E. Lock, "Equivalence of approaches to relational quantum dynamics in relativistic settings", https://arxiv.org/abs/2007.00580