No, it is not a proven fact. While some forces, such as electromagnetism, are known to have associated particles (photons in this case), there are other forces, such as gravity, that do not have a confirmed associated particle.
The main evidence for forces having associated particles comes from the study of quantum mechanics. This field of physics explains the behavior of particles at a subatomic level, and many of its theories and calculations rely on the existence of particles associated with forces.
Not necessarily. While some forces, like electromagnetism, have a specific particle associated with them (photons), other forces do not have a confirmed associated particle. In some cases, multiple types of particles may be associated with a single force.
Yes, there are ongoing studies and experiments in the field of particle physics that aim to further understand the relationship between forces and particles. These experiments often involve the use of particle accelerators and advanced detectors to observe and analyze subatomic particles.
It is possible that the discovery of associated particles for all forces could lead to a deeper understanding of the fundamental laws of physics and potentially new theories or models. However, it is also possible that our current understanding of forces and particles is already complete and no significant changes would occur.