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arXiv · 0709.1150

Beyond Two Dark Energy Parameters

Devdeep Sarkar·Scott Sullivan·Shahab Joudaki·Alexandre Amblard·Daniel E. Holz·Asantha Cooray
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Abstract

Our ignorance of the dark energy is generally described by a two-parameter equation of state. In these approaches a particular {\it ad hoc} functional form is assumed, and only two independent parameters are incorporated. We propose a model-independent, multi-parameter approach to fitting the dark energy, and show that next-generation surveys will constrain the equation of state in three or more independent redshift bins to better than 10%. Future knowledge of the dark energy will surpass two numbers (e.g., [$w_0$,$w_1$] or [$w_0$,$w_a$]), and we propose a more flexible approach to the analysis of present and future data.

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Devdeep Sarkar, Scott Sullivan, Shahab Joudaki, Alexandre Amblard, Daniel E. Holz, Asantha Cooray. 2008-06-14. Beyond Two Dark Energy Parameters. https://doi.org/10.1103/physrevlett.100.241302

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