Re: Quantum Immortality and Information Flow (was off-list)

[Brent Meeker]

Bruno Marchal wrote:
...
What could this mean in a real world example?





Take W as the set of places in Brussels. Take R to be "accessible by 
walking in a finite number of foot steps". Then each places at Brussels 
is accessible from itself, giving that you can access it with zero 
steps, or two steps (forward, backward, ...).

Take W as the set of humans, say that aRb if a can see directly, without 
mirror, the back of b. Then a can access all humans except themselves. R 
is said to be irreflexive.

Another important "concrete" example, which will help us latter to study 
the modal logic of quantum logic. Take the worlds to be the vector of an 
Hilbert Space (or of the simpler 3-dimensional euclidian space). Say 
that a is accessible to b, i.e. aRb,  if the scalar product of a and b 
is non null (i.e. a and b are not orthogonal). 

These are good illustrative examples, but how do they apply to worlds that just 
consist of propositions?  What is the relation of accessibility in the p,q,r 
world(s)?  Is it negation?

Brent Meeker