This article aims at discussing the cosmological constant problem at a pedagogical but fully
technical level. We review how the vacuum energy can be regularized in flat and curved …

We study the spontaneous excitation of a two-level atom in the presence of a perfectly
reflecting mirror, when the atom, or the mirror, is uniformly accelerating in the framework of …

Using standard results from statistics, we show that for Gaussian quantum systems the
distribution of a time measurement at a fixed position can be directly inferred from the …

We give a general overview of various flavours of the equivalence principle in classical and
quantum physics, with special emphasis on the so-called weak equivalence principle, and …

The weak equivalence principle (WEP) in the quantum regime has been the subject of many
studies with a broad range of approaches to the problem. Here, we tackle the problem anew …

We present a spin-induced non-geodesic effect of Dirac wave packets in a static uniform
gravitational field. Our approach is based on the Foldy-Wouthuysen transformation of Dirac …

The equivalence principle of gravity is examined at the quantum level using the diffraction in
time of matter waves in two ways. First, we consider a quasi-monochromatic beam of …

We discuss a new gravitational effect that the wave packet of a free-fall quantum particle
undergoes a spin-dependent transverse shift in Earth's gravitational field. This effect is …

We study the effect of quantum statistics on the arrival time distribution of quantum particles
computed through the probability current density. It is shown that symmetrization or …

Classical and quantum mechanical descriptions of motion are fundamentally different. The
universality of free fall (UFF) is a distinguishing feature of the classical motion (which has …