Why Boltzmann Brains Are Bad
Authors: Sean M. Carroll

Comments: 27 pages. Invited submission to a volume on Current
Controversies in Philosophy of Science, eds. Shamik Dasgupta and Brad
Weslake
Subjects: High Energy Physics - Theory (hep-th); Cosmology and
Nongalactic Astrophysics (astro-ph.CO); General Relativity and Quantum
Cosmology (gr-qc); History and Philosophy of Physics (physics.hist-ph)

Some modern cosmological models predict the appearance of Boltzmann
Brains: observers who randomly fluctuate out of a thermal bath rather
than naturally evolving from a low-entropy Big Bang. A theory in which
most observers are of the Boltzmann Brain type is generally thought to
be unacceptable, although opinions differ. I argue that such theories
are indeed unacceptable: the real problem is with fluctuations into
observers who are locally identical to ordinary observers, and their
existence cannot be swept under the rug by a choice of probability
distributions over observers. The issue is not that the existence of
such observers is ruled out by data, but that the theories that
predict them are cognitively unstable: they cannot simultaneously be
true and justifiably believed.

-- 
You received this message because you are subscribed to the Google Groups 
"Everything List" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to everything-list+unsubscr...@googlegroups.com.
To post to this group, send email to everything-list@googlegroups.com.
Visit this group at https://groups.google.com/group/everything-list.
For more options, visit https://groups.google.com/d/optout.

Reply via email to