  The past decade has witnessed a surge of interest in exploring emergent
particles in condensed matter systems. Novel particles, emerged as excitations
around exotic band degeneracy points, continue to be reported in real materials
and artificially engineered systems, but so far, we do not have a complete
picture on all possible types of particles that can be achieved. Here, via
systematic symmetry analysis and modeling, we accomplish a complete list of all
possible particles in time reversal-invariant systems. This includes both
spinful particles such as electron quasiparticles in solids, and spinless
particles such as phonons or even excitations in electric-circuit and
mechanical networks. We establish detailed correspondence between the particle,
the symmetry condition, the effective model, and the topological character.
This obtained encyclopedia concludes the search for novel emergent particles
and provides concrete guidance to achieve them in physical systems.
