A1 - Quintessence, Branes and Higher Dimensions
Extra dimensions provide prominent schemes for the explanation of Dark Energy. Being curled up on
a tiny length scale, they evade direct observation. Theoretically, extra dimensions are well-motivated
in fundamental theories such as string theory. Scenarios for moduli stabilisation affect Dark Energy as
well as particle physics. Thus, indirect information on Dark Energy is expected from particle physics
experiments. To utilise these exciting relations, models will be studied in their full extra-dimensional
complexity. Mechanisms explaining the scale of Dark Energy will be identifed. Fundamental constants
varying in time and extra long range forces besides gravity constrain viable models.