Hi Norman,
I entirely agree with Julian Barbour. A fundamental notion of
time would act as a pointer indicating what is real (things that are happening
now) and what was real and what will be real. Most of us here on the everything
list believe that in a certain sense 'everything exists', so the notion of a
fundamental time would be contrary to this idea. I think that that most here on
the list would consider time as a first person phenomena.
Saibal
----- Oorspronkelijk bericht -----
Verzonden: Monday, May 30, 2005 06:04
PM
Onderwerp: Re: objections to QTI
Hi Saibal and Stathis,
This scenario that you are
discussing reminds me of this interview with Julian Barbour where he proposes
that "time" is an illusion. If you agree or disagree with
Barbour, I'd like to hear why.
Norman Samish
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ----- Original
Message ----- From: "Saibal Mitra" <[EMAIL PROTECTED]> To:
"Stathis Papaioannou" <[EMAIL PROTECTED]>;
<everything-list@eskimo.com> Sent: Monday, May 30, 2005 8:28
AM Subject: Re: objections to QTI
Hi Stathis, I think that your
example below was helpful to clarify the disagreement. You say that
randomly sampling from all the files is not 'how real life works'.
However, if you did randomly sample from all the files the result would not be
different from the selective time ordered sampling you suggest, as long as the
effect of dying (reducing the absolute measure) can be ignored. If I'm
sampled by the computer, I'll have the recollection of having been a continuum
of previous states, even though these states may not have been sampled for
quite some while. I'll subjectively experience a linear time evolution. The
order in which the computer chooses to generate me at various instances
doesn't matter. There are a few reasons why I believe in the ''random
sampling''. First of all, random sampling seems to be necessary to avoid the
Doomsday Paradox. See this article written by Ken Olum:
http://arxiv.org/abs/gr-qc/0009081He
explains here why you need the Self Indicating Assumption. The self indicating
assumption amounts to adopting an absolute measure that is proportional to the
number of observers. Another reason has to do with the notion of time. I
don't believe that events that have happened or will happen are not real while
events that are happening now are real. They have to be treated in the same
way. The fact that I experience time evolution is a first person
phenomena. Finally, QTI (which more or less follows if you adopt the
time ordered picture), implies that for the most part of your life you should
find yourself in an a-typical state (e.g. very old while almost everyone else
is very young).
-Saibal -------------------------------------------------
-----
Oorspronkelijk bericht ----- Van: "Stathis Papaioannou"
<[EMAIL PROTECTED]> Aan:
<everything-list@eskimo.com> Verzonden: Monday, May 30, 2005 04:02
PM Onderwerp: objections to QTI
> I thought the following analogy
might clarify the point I was trying to make in recent posts to the "Many
Pasts? Not according to QM" thread, addressing one objection to
QTI. You are a player in the computer game called the Files of
Life. In this game the computer generates consecutively numbered
folders which each contain multiple text files, representing the
multiple potential histories of the player at that time point. Each
folder F_i contains N_i files. The first folder, F_0, contains N_0
files each describing possible events soon after your birth. You choose
one of the files in this folder at random, and from this the
computer generates the next folder, F_1, and places in it N
files representing N possible continuations of the story. If you die
going from F_0 to F_1, that file in F_1 corresponding to this event
is blank, and blank files are deleted; so for the first folder
N_0=N, but for the next one N_1<=N, allowing for deaths. The game then
continues: you choose a file at random from F_1, from this file the
computer generates the next folder F_2 containing N_2 files, then
you choose a file at random from F_2, and so on. It should be
obvious that if the game is realistic, N_i should decrease
with increasing i, due to death from accidents (fairly constant) +
death from age related disease. The earlier folders will therefore
on average contain many more files than the later folders. Now, it is
argued that QTI is impossible because a randomly sampled observer
moment from your life is very unlikely to be from a version of you
who is 1000 years old, which has very low measure compared with a
younger version. The equivalent argument for the Files of Life would be
that since the earlier files are much more numerous than the later
files, a randomly sampled file from your life (as created by playing the
game) is very unlikely to represent a 1000 year old version of you,
as compared with a younger version. This reasoning would be sound
if the "random sampling" were done by mixing up all the files, or
all the OM's, and pulling one out at random. But this is not how
the game works and it is not how real life works. From the first person
viewpoint, it doesn't matter how many files are in the folder because you
only choose one at each step, spend the same time at each step, and
are no more likely to find yourself at one step rather than
another. As long as there is at least *one* file in the next folder, it
is guaranteed that you will continue living. Similarly, as long as
there is at least *one* OM in your future which represents a
continuation from your present OM, you will
continue living. --Stathis
Papaioannou
|