1201.1000 (Julien Carron)
Julien Carron
Using recent fits to numerical simulations, we show that the entire hierarchy
of moments ceases to provide a complete description of the convergence
one-point probability density function already for values of the associated
matter fluctuations variance as low as 0.1, still in the weak lensing regime.
This suggests that the full correlation function hierarchy of the convergence
field becomes quickly generically incomplete and a very poor cosmological probe
on non linear scales. At the scale of unit variance, only 5 % of the Fisher
information content of the one-point probability density function is still
contained in its hierarchy of moments, making clear that information escaping
the hierarchy is a far stronger effect than information propagating to higher
order moments. It follows that the constraints on cosmological parameters
achievable through extraction of the entire hierarchy become suboptimal by
large amounts. A simple logarithmic mapping makes the moment hierarchy well
suited again for parameter extraction, putting 80% of the total information
back into the first two and 95% in the first three members.
View original:
http://arxiv.org/abs/1201.1000
No comments:
Post a Comment