Goldstinos

Goldstinos are hypothetical particles that are predicted to exist in certain extensions of the Standard Model of particle physics. The name "goldstino" is a portmanteau of "golden" and "supersymmetric partner," reflecting the particle's role in supersymmetric theories. In these theories, every known particle has a supersymmetric partner, and goldstinos are the supersymmetric partners of the goldstino bosons, which are associated with broken supersymmetry.

Goldstinos are predicted to be very light, often much lighter than other supersymmetric particles. This is because they are the remaining unabsorbed Nambu-Goldstone bosons after supersymmetry breaking. Due to their light mass, goldstinos are expected to have a long lifetime and low velocity, making them difficult to detect directly. However, their presence can be inferred through indirect effects, such as modifications to the cosmic microwave background and the abundance of dark matter.

Goldstinos are of particular interest in the context of thermal dark matter. In some models, goldstinos can account for the observed dark matter relic density. They can also play a role in the early universe, contributing to the production of other particles and potentially influencing the process of baryogenesis.

Despite their theoretical interest, goldstinos remain purely hypothetical. No experimental evidence for their existence has been found to date. Ongoing and future particle physics experiments, such as those at the Large Hadron Collider, aim to search for signs of supersymmetry and, by extension, goldstinos. If discovered, goldstinos would provide valuable insights into the nature of supersymmetry and the fundamental forces of the universe.