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 …

Accelerated universe from gravity leaking to extra dimensions Page 1 Accelerated universe
from gravity leaking to extra dimensions Cédric Deffayet* and Gia Dvali† Department of …

arxiv:hep-ph/0307284v1 22 Jul 2003 Page 1 arxiv:hep-ph/0307284v1 22 Jul 2003
INVERSE-SQUARE LAW TESTS 1 PACS Codes 04.80.-y, 11.25.-w, 04.50.th Page 2 2 …

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 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 …

This review is dedicated to recent progress in the field of classical, interacting, massive spin-
2 theories, with a focus on ghost-free bimetric theory. We will outline its history and its …

We address the question of whether a graviton could have a small nonzero mass. The issue
is subtle for two reasons: there is a discontinuity in the mass in the lowest tree-level …

We show that inflation with a quadratic potential occurs naturally in theories where an
axionlike field mixes with a 4-form. Such an axion is massive, with the mass which arises …

The symmetron is a scalar field associated with the dark sector whose coupling to matter
depends on the ambient matter density. The symmetron is decoupled and screened in …