Figure 1:
Redshift range over which upcoming observations may probe the cosmic density.
Error bars are a forecast for the
SNAP satellite.
Please click here to get a postscript file with
the paper.
Click if
you are interested in other research of mine.
Measuring the metric:
a parametrized post-Friedmanian approach
to the cosmic dark energy problem
Author:
Max Tegmark
Abstract:
We argue for a ``parametrized post-Friedmanian'' approach to linear
cosmology, where the history of expansion and perturbation growth is
measured without assuming that the Einstein Field Equations hold. As
an illustration, a model-independent analysis of 92 type Ia
supernovae demonstrates that the curve giving the expansion history
has the wrong shape to be explained without some form of dark energy
or modified gravity. We discuss how upcoming lensing, galaxy
clustering, cosmic microwave background and Lyman alpha forest
observations can be combined to pursue this program, which
generalizes the quest for a dark energy equation of state, and
forecast the accuracy that the proposed
SNAP satellite
can attain.
Reference info:
astro-ph/0101354, Phys. Rev. D, in press
Links:
My most recent estimates of cosmological parameters within the more conventional
context are here.
You'll find some earlier work of mine on combining different types of complementary
data here.
Figure 7:
Shaded regions show ranges of scale and redshift over which
various observations are likely to probe the linear growth factor
over the next few years.
The lower left region, delimited by the dashed line, is the non-linear
regime.
Return to my home page
This page was last modified September 17, 2002.
max@physics.upenn.edu