Hi all,
On Thursday Joel Huber will present his master thesis on ''A Weak Measurement Based Toy Model Probe Quantum Properties in a Cosmological Setting’’. The talk will take place in HIT E 41.1 at 14:00.
Best,
Ladina
*******
TITLE: A Weak Measurement Based Toy Model Probe Quantum Properties in a Cosmological Setting
ABSTRACT: Probing quantum properties in cosmology could offer profound insights into the fundamental nature of the universe. Here, we present a novel perspective on the detectability of quantum properties in cosmology. Firstly, we motivate a set of fundamental limitations inherent to observational cosmology, which defines the abstract notion of a cosmological setting. We then translate these limitations into operational constraints for a general quantum system. We propose a toy model, based on quantum weak measurements, and show how the limitations can be successfully circumvented by studying weakly coupled pointer degrees of freedom. Using quantum information techniques, we find that non-commutativity of observables can be inferred by comparing measurement statistics. However, this finding is probabilistic and its significance is fundamentally limited by the weakness of the measurements. Although the significance can be improved by assuming a decomposition of the system into identical subsystems, this result can only provide a hint, and not conclusive evidence, for the quantum nature of the system. Finally, we investigate generalised Leggett-Garg inequalities, which separate classical from non-classical temporal correlations. We demonstrate that they cannot be violated using three consecutive weak measurements while remaining agnostic about the underlying interactions.