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

From: Brent Meeker <meekerdb.domain.name.hidden>
Date: Wed, 07 Dec 2005 17:31:01 -0800

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
Received on Wed Dec 07 2005 - 21:20:31 PST