The superposition principle is the cornerstone of quantum mechanics, leading to a variety of
genuinely quantum effects. Whether the principle applies also to macroscopic systems or …

We discuss effects of loss of coherence in low energy quantum systems caused by or related
to gravitation, referred to as gravitational decoherence. These effects, resulting from random …

Advances in quantum technologies are giving rise to a revolution in the way fundamental
physics questions are explored at the empirical level. At the same time, they are the seeds …

This note derives the stochastic differential equations and partial differential equation of
general hybrid quantum--classical dynamics from the theory of continuous measurement …

Quantum theory is incredibly successful, explaining the microscopic world with great
accuracy, from the behaviour of subatomic particles to chemical reactions to solid-state …

Levitated nano-oscillators are promising platforms for testing fundamental physics and
quantum mechanics in a new high mass regime. Levitation allows extreme isolation from the …

Noninterferometric experiments have been successfully employed to constrain models of
spontaneous wave function collapse, which predict a violation of the quantum superposition …

Spontaneous collapse models are phenomological theories formulated to address major
difficulties in macroscopic quantum mechanics. We place significant bounds on the …

The spontaneous localization mechanism of collapse models induces a Brownian motion in
all physical systems. This effect is very weak, but experimental progress in creating ultracold …

Matter-wave interferometry is a direct test of the quantum superposition principle for massive
systems, and of collapse models. Here we show that the bounds placed by matter-wave …