Understanding Cosmic Acceleration: Connecting Theory and Observation
==================================================================

 The mysteries of cosmic acceleration at early and late times are two 
 of the biggest questions confronting cosmologists today. The initial 
 conditions of the Big-Bang are thought to have been set during 
 ``inflation'', an era of almost exponential expansion in the 
 primordial universe, which also provides a mechanism to generate the 
 primordial fluctuations which are seen today in the cosmic microwave 
 background
 (CMB)
 radiation. Current cosmological data are, for the first time, precise 
 enough to allow detailed observational tests of inflationary models. I
 will describe current and future efforts to understand the 
 microphysics of inflation, focusing in particular on CMB data. 
 Intriguingly, the cosmological expansion may be accelerating once 
 again, as confirmed by several independent data-sets. These 
 observations can be explained if the universe is dominated by a 
 negative-pressure component, ``dark energy'', which makes up roughly 
 three-quarters of the cosmological energy density.
 Theoretical models for the dark energy include the cosmological 
 constant and a dynamical component. I will show how tools previously 
 used to extract information about inflationary models can be brought 
 to bear on the problem of constraining the physics of dark energy, and
discuss the prospects for future observations.