Hi Christian,
Glad you enjoyed my work. I look forward to reading yours soon.
Thanks for putting your questions and comments in a numbered list, so here I go point by point:
1) "Displaying for its operator every possible future, but could not show which one will occur" is similar to the collapse of the wave function in quantum mechanics. This should be the Bohr's point of view, while the Cassandra machines should represent Einstein's point of view. I think you suggest a third, intermediate point of view. Something like "a deterministic quantum mechanics".
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That's a cool observation. Yes, some kind of deterministic quantum mechanics is indeed the most attractive kind of interpretation of quantum mechanics in my opinion. My favorite paper about quantum interpretation is called "Quantum mechanics of measurement" by N.J. Cerf and C. Adami (1997). I've gotten something new and valuable every time I've read it, but I would probably need a Ph.D. in physics to be able to understand all of it.
2) I like your statement that "One must realize that we are still at a very early stage of science and technology". In science we need both humility and optimism.
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Yes, I'm glad you like it. Every generation seems to fancy themselves as somehow finally being at the pinnacle of progress, and every generation which believes such a thing is wrong.
3) Don't you think that it is, in a certain sense, a full circle that a case wherein an individual or group helps to bring certain future outcomes to fruition, based upon what has been learned in viewer foreknowledge?
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Yes, that's the (self-consistent) nature of it.
4) What is the difference between "unmistakable viewer foreknowledge" and "effectively unmistakable viewer foreknowledge"?
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Glad you asked. Technical note six offers a number of methods that FM operators might use to confirm instances of viewer foreknowledge, as such. So, "effectively unmistakable viewer foreknowledge" simply refers to viewer foreknowledge that can only be recognized as such after these techniques are used. Since, it is unmistakable in the end, I thought a good term would be effectively unmistakable. This term of convenience would not have been necessary if there was no length restriction for the essay--in that case, technical note six would have been part of the text.
5) What is called "second-time-around fallacy" in philosophy is called "chronology protection conjecture" in physics.
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Well, there is a definite distinction between the two. From Wikipedia: "The chronology protection conjecture is a conjecture by the physicist Professor Stephen Hawking that the laws of physics are such as to prevent time travel on all but sub-microscopic scales." However, the second-time-around fallacy essentially states that it is a fallacy to imagine that the past can be altered in a do-over initiated by the visit of a time traveler. The second-time-around fallacy is perfectly consistent with widespread use of pastward time travel, because time travel does not involve even the possibility of making changes to the past. That's why, on page 6, I refer to "time travel paradoxes" as a misnomer. They should henceforward be called "past alteration paradoxes," since the paradoxical results that have mistakenly been associated with time travel could only emerge from changes to the past, yet genuine time travel would strictly forbid any changes to the past whatsoever.
6) When Kurt Gödel have shown that closed timelike curves could in principle exist in general relativity, Einstein claimed that "such a potential existence gives me shivers running down my spine"
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That seems like an appropriate response to what was, in my opinion, one of the most important scientific developments of the 20th Century.
7) On one hand, the idea that the future will steer humanity looks intriguing. On the other and, don't you think that removing the element of surprise could mean that life will become bore? See also point 3).
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When foreknowledge machine technology is well-understood and has long been applied for maximum effect, if such a day ever comes, I really don't think it will be boring to know that one's children will grow up in a world that will be safe all their lives, without war, systematic oppression, corruption, or famine. To my way of thinking, that sounds like the opposite of boring.
Christian, thanks very much for your comments and questions. We could certainly do this again, if you should find that you have more.
Warmly,
Aaron