stabilies

Stabilies are a hypothetical class of elementary particles that are theorized to be exceptionally stable, meaning they have extremely long lifetimes, potentially comparable to the age of the universe. The concept of stabilies arises in various theoretical physics frameworks, often as a consequence of certain symmetries or conservation laws.

One context where stabilies might appear is in theories beyond the Standard Model of particle physics. For example, in some Grand Unified Theories (GUTs), particles that are stable under the Standard Model interactions could decay very slowly through new, extremely weak interactions predicted by the GUT. The lightest particle with conserved quantum numbers in such theories is often a candidate for a stable particle.

Another area where stable particles are discussed is in supersymmetry (SUSY). Supersymmetric extensions to the Standard Model often predict a new set of partner particles for known particles. If R-parity is conserved, the lightest supersymmetric particle (LSP) is typically stable. The LSP is a common candidate for dark matter due to its potential stability and interaction properties.

The experimental search for stable particles, or particles with extremely long lifetimes, is a significant area of research. Direct detection experiments, such as those looking for dark matter, and precision measurements of particle decay rates are employed to constrain or discover such particles. The discovery of a truly stable elementary particle beyond those already known (like the electron or proton, though proton decay is theoretically possible in some models) would have profound implications for our understanding of fundamental physics and cosmology.