5 papers
The Paradox of the Third Particle is classical
Ladina Hausmann, Renato Renner
The Paradox of the Third Particle arises when particles are described relative to one of them serving as a reference frame. Although it is typically attributed to quantum superposi…
The Perspectives of Non-Ideal Quantum Reference Frames
Sébastien Christophe Garmier, Ladina Hausmann, Esteban Castro-Ruiz
We define the perspective of any quantum reference frame (QRF) and construct reversible transformations between different perspectives. Our construction is based on two principles…
Against probability: A quantum state is more than a list of probability distributions
Ladina Hausmann, Renato Renner
The state of a quantum system can be represented by listing the outcome probabilities for a tomographically complete set of measurements. Such representations appear throughout phy…
The firewall paradox is Wigner's friend paradox
Ladina Hausmann, Renato Renner
The firewall paradox, a puzzle in black hole physics, depends on an implicit assumption: a rule that allows the infalling and the outside observer to combine their perspectives. Ho…
Measurement events relative to temporal quantum reference frames
Ladina Hausmann, Alexander Schmidhuber, Esteban Castro-Ruiz
The Page-Wootters formalism is a proposal for reconciling the background-dependent, quantum-mechanical notion of time with the background independence of general relativity. Howeve…