In a Physical Review Letters study, the HOLMES collaboration has achieved the most stringent upper bound on the effective electron neutrino mass ever obtained using a calorimetric approach, setting a limit of less than 27 eV/c² at 90% credibility.

This result validates a decades-old experimental vision and demonstrates the scalability needed for next-generation neutrino mass experiments.

While oscillation experiments have measured the differences between neutrino mass states, the actual individual mass values—the absolute neutrino mass scale—remain unknown. Pinning down these values would help complete our understanding of the Standard Model of particle physics.