Talk about Pivots

Damien Martin; Andreas Albrecht

paper

Talk about Pivots

arXiv:astro-ph/0604401

Abstract

We consider two different methods of parameterizing the dark energy equation of state in order to assess possible ``figures of merit'' for evaluating dark energy experiments. The two models are $w (a) = w_{0} + (1 - a) w_{a}$ and $w (a) = w_{p} + (a_{p} - a) w_{a}$ . This brief note shows that the size of the error contours cannot change under such a reparameterization. This makes the figures of merit associated with these parameterizations mathematically identical. This also means that any ``bias'' exhibited by one model is equally present in the other.

3 pages; brief comment