Nature of Nonbaryonic Dark Matter and Dark Energy

Determine the fundamental physical nature of nonbaryonic dark matter and dark energy within the standard cosmological model, beyond their current phenomenological characterization by density fractions in observations.

Background

The paper begins by summarizing the concordance cosmological model, in which the Universe is spatially flat and contains approximately 5% baryonic matter, 25% nonbaryonic dark matter, and 70% dark energy. Although this model fits observations well, the microphysical identity of the dark components is not established.

The authors introduce the idea of holographic dark matter (HDM) as an alternative to particle-based dark matter, motivating this proposal in part by the broader unresolved question about the nature of dark matter and dark energy.