Chalnoth said:
Um, it's extraordinarily unlikely that you'll find yourself in a situation where you are unconscious and your life or death will depend upon quantum events. Remember that the regime at which quantum effects are important is extremely low temperatures or very small systems (on the order of hundreds of atoms).
Very strongly disagree.
http://en.wikipedia.org/wiki/Hardware_random_number_generator
Shot noise is a quantum phenomenon, and you can imagine a situation in which a resistor that is near tolerance fails or doesn't fail due to the current flow. For that matter you can have a situation in which a resistor fails or doesn't fail because a cosmic ray does or doesn't hit a critical item. The reason I'm under the knife in the first place may be because I was near a piece of uranium that did or did not emit an alpha particle that did or did not knock out a critical piece of DNA, that did or did not cause things to be cancerous.
Because of this, the system would have to be explicitly set up to depend upon measurements of a carefully-prepared quantum system. So yes, extremely contrived and not applicable to reality.
Not hard. Happens all of the time. You have a resistor that is about to burn out. The shot noise either puts the current over or under the limit. In one universe, it goes over, resistor burns out. Distracts the surgeon, I die.
Also it's not hard to make it happen. That's the cool thing about the Android app that I'm working on. I use a hardware random number generator to flip a coin based on quantum principles. In one universe, I go to the park and nothing happens. In another universe, I end up in a busy intersection where I get hit by a bus.
This isn't a hard experiment.
Not in the sense of quantum superpositions being an important aspect of the phenomena, which is all that is relevant for this kind of issue.
The problem here is that if you accept MWI, the wave function is *always* in a state of superposition. With Copenhagen and anything else, the wave functions collapses, the superposition disappears. With MWI, the superposition *doesn't* disappear after you do the measurement. It's just that the outcome of that measurement are in different universes which you don't notice.
So if you accept MWI, quantum superpositions are always important because they don't disappear after you do the experiment.
Part of the problem here is that the talk of quantum consciousness has been dominated by Roger Penrose, and it's pretty easy to show that his ideas are wrong. But superposition is not the only quantum effect, and even thought the electrons in my computer or a laser are nicely collapsed, quantum effects are important in both of them.
The reason this matters is that there is one missing part of MWI which is the fact that I don't feel the universe splitting. I hit my hardware random number generator. It tells me to eat steak instead of salmon, but MWI says that somewhere else there is a different me that got told to eat salmon instead of steak. Quantum suicide and immortality are ideas that try to figure out what is going on. They might be wrong, but it's not an issue that is irrelevant, and you just can't around the problem by doing what you are doing by saying that the problem doesn't matter.
I seriously doubt that my brain doesn't have some quantum noise in it, but since I'm not a neuroscientist, let's say that you are right and my brain is completely deterministic. So I couple it with a source of quantum noise, and which you can't say that the experiment is irrelevant. I write an app on my phone that flips a quantum mechanical coin, and use it to make daily decisions. At some point, the phone will make some sort of decision that will either increase or decrease my lifespan.
If you say that Fred would have to be insane to do X, Y, and Z, you are making statements about Fred assuming that Fred has pseudo-human motivations, at which people you are using the thought processes that theologians use to make statements about what Fred will do or what Fred won't do.
This kind of objection doesn't make any sense. Probabilities within MWI strictly adhere to the Born Rule, so even if you can suppose that some seemingly weird thing might exist, the probability of you finding yourself in that world is so unbelievably minuscule that it is irrelevant.
I'm not objecting. MWI implies that there is version of reality in which a mega-intelligence has created a uber-version of Disneyland. That doesn't particularly bother me.
Personally, I think it would be cool if MWI was right and there are parallel universes. I've got a lot of questions about the universe, and I'm looking forward to meeting Fred.
Richard Dawkins might not like some of the implications but that's his problem.
Finding yourself in a highly improbable universe is not irrelevant if in the other universes you don't exist at all. That's the whole point of the anthropic principle. If may be highly improbable that after you die you end up in some sort of mega-Disneyland (if you've been good), but if you run the numbers, I don't think that it's that much less likely than the odds that you were born in the first place.
Also, I'm showing a bit of my inner crackpot here. He looks and sounds a lot like Frank Tipler, and I keep my inner crackpot under control by telling it that all he has to do is to wait a few decades and see what happens.