Identity of Dark Matter

Determine the identity of dark matter in the universe, including its particle nature and properties, to resolve the longstanding uncertainty central to contemporary physics.

Background

The paper motivates new detector materials for sub-MeV dark matter by emphasizing that the nature of dark matter is still unknown. The proposed materials—TiSe2 in its charge-density-wave phase, Sr2RuO4 with an acoustic demon mode, and hole-doped diamond with tunable plasmons—are intended to provide enhanced sensitivity to light dark matter scattering and absorption, thereby contributing to efforts to resolve the fundamental question of what dark matter is.

This open problem is presented as the overarching scientific context for the work, framing the need for innovative detection strategies and materials capable of probing previously inaccessible regions of dark matter parameter space.