Entities › Hypothetical minds

Boltzmann brains

unobserved Proposed in the literature. Nobody has observed one.

Brain-like observers that appear out of rare thermal or quantum fluctuations.

Brain-like observers that appear out of rare thermal or quantum fluctuations. In some cosmological models they'd outnumber ordinary observers, and that's treated as a problem for the theory. Purely theoretical.

Sources

• Albrecht A, Sorbo L (2004) Can the universe afford inflation? Phys Rev D 70(6):063528. doi:10.1103/PhysRevD.70.063528.
• Carroll SM (2017). Why Boltzmann brains are bad. arXiv:1702.00850.