AAS 195th Meeting, January 2000
Session 125. Cosmology and Large-Scale Structure
Oral, Saturday, January 15, 2000, 2:00-3:30pm, Centennial I and II

[Previous] | [Session 125] | [Next]

[125.03] Using Perturbative Least Action to Recover Cosmological Initial Conditions

D.M. Goldberg (Princeton University Observatory)

One of the great challenges in cosmology is interpreting the observations of large scale structure. On the largest scales, this frequently means estimating the power spectrum at present and from that, using linear theory to determine the power spectrum at high redshift, and consequently, the corresponding cosmological parameters.

The problem of determining initial conditions becomes much more complex for fields which are highly non-linear. Due to mode-mode coupling in the evolution equations, the problem of finding the time-reversal operator becomes fundamentally ill-posed; that is, many different sets of initial conditions can give rise to the same final density field.

In this talk, I will discuss a new technique for time-reversing dynamics observations. Perturbative Least Action (PLA) is a variant of Least Action variational method which develops particle trajectories as perturbations from known, randomly realized paths, and can be used to generate many different sets of initial conditions, each of which will satisfy given highly nonlinear constraints at z=0.

This research was supported through a NSF graduate research fellowship.

The author(s) of this abstract have provided an email address for comments about the abstract: goldberg@astro.princeton.edu

[Previous] | [Session 125] | [Next]