Supernovae,
Dark Energy, & the Accelerating Universe - What Next?
The
Supernova Cosmology Project was surprised to discover that the expansion of the
universe is not decelerating (as expected due to gravity), but
accelerating. Apparently, some new,
unidentified "dark energy" that pervades all space is accelerating
the expansion. This is the first decade
in which we can begin to address such fundamental physics questions with a
variety of measurement techniques.
We have been using Type Ia supernovae to track the past expansion of the
universe and extrapolate its fate. We
have now embarked on new studies using this approach to constrain possible
theories of this dark energy, by improving both the statistical and systematic
uncertainties of the supernova measurements.
In particular, I will discuss the proposed new satellite, the Supernova
/ Acceleration Probe (SNAP), a 2-meter class telescope with a wide-field imager
and optical-to-near-IR spectrograph system.