Neutron stars are timelike matter with a maximum mass of about 2.34 solar masses in quantum chromodynamics (the strong color force). Black holes are spacelike matter that have no maximum mass, but a minimum mass of 2.35 solar masses. Indeed, black holes have been identified with millions or billions of solar masses.
All timelike matter is causal, while black hole spacelike matter is acausal. Acausal spacelike matter has no identifiable particle states (everything is off mass-shell in the spacelike region), no Pauli principle, no equations of motion, no equation of hydrostatic stability, no equations of state, no entropy, no temperature, no Planck constant, no Boltzmann constant, no finite temperature quantum field theory.
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