Dark Energy Phenomenology

TL;DR

This paper explores how dark energy's properties can be characterized through two key functions in cosmological observations, emphasizing the importance of understanding dark matter to fully constrain dark energy.

Contribution

It introduces two functions that describe dark energy's observational properties and highlights the necessity of detecting dark matter for comprehensive dark energy constraints.

Findings

Dark energy cannot be fully constrained without dark matter detection.

Two functions characterize dark energy's observational properties.

Measuring these functions is crucial for future cosmological studies.

Abstract

We discuss the phenomenology of the dark energy in first order perturbation theory, demonstrating that the dark energy cannot be fully constrained unless the dark matter is found, and that there are two functions that characterise the observational properties of the dark sector for cosmological probes. We argue that measuring these two functions should be an important goal for observational cosmology in the next decades.