  Several philosophical problems arising from the physics of consciousness,
including identity, duplication, teleportation, simulation, self-location, and
the Boltzmann Brain problem, hinge on one of the most deeply held but
unnecessary convictions of physicalism: the assumption that brain states and
their corresponding conscious states can in principle be copied. In this paper
I will argue against this assumption by attempting to prove the Unique History
Theorem, which states, essentially, that conscious correlations to underlying
quantum mechanical measurement events must increase with time and that every
conscious state uniquely determines its history from an earlier conscious
state. By assuming only that consciousness arises from an underlying physical
state, I will argue that the physical evolution from a first physical state
giving rise to a conscious state to a second physical state giving rise to a
later conscious state is unique. Among the consequences of this theorem are
that: consciousness is not algorithmic and a conscious state cannot be uploaded
to or simulated by a digital computer; a conscious state cannot be copied by
duplicating a brain or any other physical state; and a conscious state cannot
be repeated or created de novo. These conclusions shed light on the physical
nature of consciousness by rendering moot a variety of seemingly paradoxical
philosophy and science fiction problems.
