The Swampland program aims to distinguish effective theories which can be completed into
quantum gravity in the ultraviolet from those which cannot. This article forms an introduction …

We review in detail a number of approaches that have been adopted to try and explain the
remarkable observation of our accelerating universe. In particular we discuss the arguments …

Massive gravity has seen a resurgence of interest due to recent progress which has
overcome its traditional problems, yielding an avenue for addressing important open …

We conducted three torsion-balance experiments to test the gravitational inverse-square law
at separations between 9.53 mm and 55 μ m, probing distances less than the dark-energy …

We review recent mechanical experiments that test some of the most basic principles of
physics including the weak and strong forms of the Equivalence Principle, the gravitational …

Cosmological implications of neutrinos are reviewed. The following subjects are discussed
at a different level of scrutiny: cosmological limits on neutrino mass, neutrinos and primordial …

Higher-order theories of gravity have recently attracted a lot of interest as alternative
candidates to explain the observed cosmic acceleration without the need of introducing any …

We provide the perturbative and non‐perturbative arguments showing that theories with
large number of species of the quantum fields, imply an inevitable hierarchy between the …

We investigate the effects of viscosity terms depending on the Hubble parameter and its
derivatives in the dark energy equation of state. Such terms are possible if dark energy is a …

Modifications of general relativity provide an alternative explanation to dark energy for the
observed acceleration of the universe. We review recent developments in modified gravity …