Boltzmann brain

The Boltzmann brain is a similar idea.

For every universe with the level of organization we see, there should be an enormous number of lone Boltzmann brains floating around in unorganized environments.

A Boltzmann brain is a hypothesized self-aware entity which arises due to random fluctuations out of a state of chaos.

Boltzmann brains are often referred to in the context of the "Boltzmann brain paradox" or "problem".

Pioneering work on the subtleties of very late-time cosmology in the presence of a positive cosmological constant, and the "Boltzmann brain" problem (with Lisa Dyson and Leonard Susskind)

The idea is named for the physicist Ludwig Boltzmann (1844-1906), who advanced an idea that the known universe arose as a random fluctuation, similar to a process through which Boltzmann brains might arise.

However, as current data suggest that the Universe is flat, and thus will not collapse in on itself after a finite time, the infinite future potentially allows for the occurrence of a number of massively improbable events, such as the formation of a Boltzmann brain.

The Boltzmann brain paradox is that any observers (self-aware brains with memories like we have, which includes our brains) are therefore far more likely to be Boltzmann brains than evolved brains, thereby at the same time also refuting the selection-bias argument.