Before WIMPs: Neutrinos and the origins of particle dark matter

Abstract

After four decades of null-results, the experimental quest to discover a dark matter particle ardently continues. While confidence in the leading candidate, the Weakly Interacting Massive Particle (WIMP), is waning, its explanatory success still shapes current experimental approaches and theoretical expectations - from underground detecting efforts in Europe, China, and the U.S. to modern theories of cosmic structure. This paper traces the origins of this particle-based paradigm to a critical predecessor: the neutrino-dominated universe. Proposed in the early 1970s as a solution to extra-galactic anomalies, neutrinos became the leading explanation of 'missing matter' following experimental hints of neutrino mass in 1980. Although short-lived, the model's coherent picture of cosmic evolution and structure formation set strong conceptual and methodological standards - providing critical impetus to the field of particle cosmology. Examining this history invites renewed reflection on how such past aims and expectations continue to guide dark matter inquiry today.