We have previously shown that three approaches to relational quantum dynamics—
relational Dirac observables, the Page-Wootters formalism and quantum deparametrizations …

At the intersection of quantum theory and relativity lies the possibility of a clock experiencing
a superposition of proper times. We consider quantum clocks constructed from the internal …

In general relativity, the description of spacetime relies on idealised rods and clocks, which
identify a reference frame. In any concrete scenario, reference frames are associated to …

We generalize the Unruh-DeWitt detector model to second quantization. We illustrate this
model by applying it to an excited particle in a superposition of relativistic velocities. We …

In a quantum world, reference frames are ultimately quantum systems too–but what does it
mean to" jump into the perspective of a quantum particle"? In this work, we show that …

Atomic clock interferometers are a valuable tool to test the interface between quantum theory
and gravity, in particular via the measurement of gravitational time dilation in the quantum …

A simple but powerful particle detector model consists of a two-level system coupled to a
field, where the detected particles are the field excitations. This is known as the Unruh …

Since their first introduction, Quantum Reference Frame (QRF) transformations have been
extensively discussed, generalising the covariance of physical laws to the quantum domain …

Hawking radiation is the proposed thermal black-body radiation of quantum nature emitted
from a black hole. One common way to give an account of Hawking radiation is to consider a …

According to relativity, the reading of an ideal clock is interpreted as the elapsed proper time
along its classical trajectory through spacetime. In contrast, quantum theory allows the …