Tim May wrote:
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.)
What should one do? What did all of you actually do? What did Moravec do, what did I do, what did Tegmark do?
Tim, this example is completely inapplicable to the case of QS just like you would not set up a relativistic experiment to measure the slowing of a clock in which the clock travels one mile per hour. To get significant results you must travel a significant fraction of the speed of light.
QS decisions are significantly different from "classical" decisions when the life of the experimenter is at stake, (or as I pointed out earlier the memory of the quantum suicide machine in the mind of the experimenter must be at stake). The amount "at stake" does not have to be 100% as I shall explain below. Even intentional death (suicide) is not necessary. The incoming death may be entirely unintentional!
This reminds me of a science fiction story I read about 30 years ago in which the end of the world was forecasted for midnight. A zealous journalist was faced with preparing a story to be published the next day (after the world ended.) He accomplished the task by stating in the story that the forecast was in fact in error and that the world had not ended. In the branch of the manyworld, in which he remained alive, his story was right, and he therefore, astonished the public with his prescience. He made the right QS decision.
As you can see, suicide is not necessary. One could be on death row - in other words have a high probability of dying - and make decisions based on the probability of remaining alive.
Being on death row, dying of cancer, travelling on an airline, or sleeping in our bed involve different probability of death... These situations only differ in degrees. We are all in the same boat so to speak. We are all likely to die sooner or later. The closer the probability of death, the more important QS decision becomes.
The guy on death row must include in his QS decision making the factor that will save his life: probably a successful appeal or a reprieve by the state governor. The person flying in an airline should include in his QS decision process the fact that the plane will not have a mechanical failure or be hijacked. The person dying of cancer must include the possibility of finding a cure to cancer, or of being successfully preserved somehow by cryogenic means.
As you see, suicide is not necessary for QS decisions.
In addition the whole issue of "measure" is in my opinion suspect as I have already extensively stated on this list. See below.
>Lev Vaidman wrote that we must care about all our 'successive' >worlds in proportion to their measures of existence [Behavior >Principle]. He does not agree to play the 'quantum Russian >roulette' because the measure of existence of worlds with >himself dead is be much larger than the measure of existence >of the worlds with himself alive and rich!
I agree that QS is unethical. Yet, the reasons given by Vaidman could be unjustified because maximizing measure may not be possible if measure is already infinite - a clue that measure is infinite is that the manyworld seem to vary according to a continuum since schroedinger function is continuous. George