 Hidden sector

The term "hidden sector" can refer to various concepts depending on the context in which it is used. Here are a few interpretations: 1. **Physics and Cosmology**: In theoretical physics, particularly in the context of supersymmetry and string theory, a "hidden sector" is often used to describe a part of the universe's particle physics that interacts very weakly with the observable sector (the particles and forces we are familiar with, like quarks and electrons).