We propose a new elementary particle, NiNo, characterized by a purely repulsive force with ordinary matter and with other NiNo particles. This repulsive force constitutes a candidate for the missing fifth force long sought by physicists. With an estimated mass below current measurement precision (< 1×10⁻³¹ g), NiNo has evaded detection. We hypothesize that at least one NiNo resides in the nucleus of every stable atom, acting as the sole stabilizer preventing atomic collapse. The number of NiNo particles varies with the Z/N ratio; deviation from a specific "stability window" (too few or too many NiNo) explains radioactive decay and nuclear instability. NiNo also accumulates at high densities inside planets, stars, galaxies, and black holes. We present an explanation for supernova explosions based on critical NiNo density thresholds. We propose three detection experiments: (1) a differential centrifugal balance in deep space, (2) a search for anomalies in existing particle accelerator data, and (3) a ground-based experiment using a hollow gold sphere inside a particle accelerator operating at low energies to trap NiNo without damaging the sphere.
Nedal Nezam (Fri,) studied this question.