Exotic matter

There are several proposed types of exotic matter:

• Hypothetical particles and states of matter that have "exotic" physical properties that would violate known laws of physics, such as a particle having a 0.
• Hypothetical particles and states of matter that have not yet been encountered, but whose properties would be within the realm of mainstream physics if found to exist.
• Several particles whose existence has been experimentally confirmed that are conjectured to be exotic hadrons and within the Standard Model.
• States of matter that are not commonly encountered, such as Bose–Einstein condensates, fermionic condensates, nuclear matter, quantum spin liquid, string-net liquid, supercritical fluid, color-glass condensate, quark–gluon plasma, Rydberg matter, Rydberg polaron, photonic matter, and time crystal but whose properties are entirely within the realm of mainstream physics.
• Forms of matter that are poorly understood, such as dark matter and mirror matter.
• Ordinary matter placed under high pressure, which may result in dramatic changes in its physical or chemical properties.
• Degenerate matter
• Exotic atoms