Re: Quantum suicide without suicide

From: Tim May <tcmay.domain.name.hidden>
Date: Wed, 8 Jan 2003 13:27:10 -0800

On Wednesday, January 8, 2003, at 10:58 AM, George Levy wrote:

> In the original verision of Quantum Suicide (QS), as understood in
> this list, the experimenter sets up a suicide machine that kills him
> if the world does not conform to his wishes. Hence, in the branching
> many-worlds, his consciousness is erased in those worlds, and remains
> intact in the worlds that do satisfy him.
>
> Is it possible to perform such a feat without suicide? What is the
> minimum "attrition" that is required and still get the effect of
> suicide?

Hawking had a good line: "When I hear about Schrodinger's Cat, I reach
for my gun."

Slightly modify the QS conditions in another direction: instead of
dying immediately, one goes onto death row to await execution. Or one
is locked in a box with the air running out. And so on.

This removes the security blanket of saying "Suicide is painless, and
in all the worlds you have not died in, you are rich!" In 99.9999...99%
of all worlds, you sit in the box waiting for the air to run out.

I don't know if there are other worlds in the DeWitt/Graham sense
(there is no reason to believe Everett ever thought in these terms),
but if they "exist" they appear to be either unreachable by us, or
inaccessible beyond short times and distances (coherence issues).

In particular, it seems to me there's a "causal decision theory"
argument which says that one should make decisions based on the
maximization of the payout. And based on everything we observe in the
world around us, which is overwhelmingly classical at the scales we
interact in, this means the QS outlook is deprecated.

Consider this thought experiment: Alice is facing her quantum mechanics
exam at Berkeley. She sees two main approaches to take. First, study
hard and try to answer all of the questions as if they mattered.
Second, take the lessons of her QS readings and simply _guess_, or
write gibberish, killing herself if she fails to get an "A." (Or, as
above, facing execution, torture, running out of air, etc., just to
repudiate the "suicide is painless" aspect of some people's argument.)

 From rationality, or causal decision theory, which option should she
pick?

All indications are that there are virtually no worlds in which random
guessers do well. (The odds are readily calcuable, given the type of
exam, grading details, etc. We can fairly easily see that a random
guesser in the SATs will score around 550-600 combined, but that a
random guesser in a non-multiple-choice QM exam will flunk with
ovewhelming likelihood.)

What should one do? What did all of you actually do? What did Moravec
do, what did I do, what did Tegmark do?

--Tim May
Received on Wed Jan 08 2003 - 16:31:25 PST