George Levy wrote:
A lot of confusion seems to arise about what an observer-moment is.
I would like to propose the following distinction between a physical
observer-moment and a psychological observer moment, along the same lines
that I discussed under the thread copying.
A physical observer moment is defined by an observer physical
quantum state accompanied by the set of all consistent histories justifying
this state. It requires and includes a causal light cone to be drawn from
that point extending toward the past (and expending toward the future).
Hence a given physical OM includes several pasts and multiple futures.
Because of the QM Non-cloning theorem two identical physical OMs cannot be
copied. In addition because two identical OMs must comprise identical causal
cones they must be one and the same in the same visible universe. Of course
copies may exist beyond the causal cone or in other universes.
Since a physical OM cannot be copied, the measure of a physical OM
cannot be increased within the causal cone.
A psychological observer moment is defined by a set of observer
states which cannot be distinguished from each other by a subjective test
performed by the observer. This definition is significantly looser than the
one for physical observer-moment. Thus a single psychological observer
moment can encompass a large number of physical observer moments. Note that
according to this definition the set of observer states may also encompass
states with inconsistent histories as long as they are indistinguishable. (I
am not sure if I should enforce "consistent histories" on psychological OMs
by replacing "observer states" by "physical observer moments")
The consideration of what is the measure of a psychological observer
moment forces us to differentiate between physical first person and
psychological first person.
From a physical first person point of view, a psychological OM can
include multiple physical OMs and therefore can have a high or low measure.
However, from a psychological first person point of view, since all the
physical OMs are indistinguishable, the measure cannot be increased by
increasing the number of physical OMs.
What sort of subjective test are we talking about re. distinguishable
psychological observer moments? Something like "do I remember the lady in
the red dress?". We can't really compare two psychological observer moments
How do we account for "identity" among all this. Am I a physical first
person, or a psychological first person? Or both (context dependant)?
I (both my physical and psychological first persons) am still confused :).