But this is clearly false: Demonstrably, xenon does not act as it does in our universe. In particular, it forms a compund with yttrium and zinc. Likewise, zinc is clearly different from our-universe zinc, which absolutely does not form compounds with xenon.
Never mind the water, or the XeYZn compound. In our universe, if you leave elemental xenon, yttrium, and zinc in a box together, they will not form a compund. That’s not true in the other universe, or how does XeYZn form in the first place? And incidentally, what about other-universe hydrogen and oxygen, do they no longer bond to form water?
That’s not true in the other universe, or how does XeYZn form in the first place? And incidentally, what about other-universe hydrogen and oxygen, do they no longer bond to form water?
When hydrogen and oxygen are combined, it causes a bizarre nuclear reaction that results in XeYZn.
Well, that breaks conservation of energy right there, so now you’ve got a really bizarre set of laws. What happens when you run electricity through water? In our universe this results in hydrogen and oxygen.
I really don’t think you can save this thought experiment; the laws of physics are too intimately interconnected.
Yes. I thought I was pretty clear on that. Breaking conservation of energy is barely touching how bizarre it is. It still acts like our universe, except where H20 and XeYZn are concerned.
What happens when you run electricity through water?
If you run electricity through XeYZn, it results in hydrogen and oxygen. If you even have H20, it will immediately turn into zenon, yttrium, and zinc.
Ok. You are talking about Omega constantly intervening to make things behave as they do in our universe. But in that case, what is the sense in which XYZ is not, in fact, H2O? How do the twin-universe people know that it is in fact XeYZn? Indeed, how do we know that our H2O isn’t, in fact, XeYZn? It looks to me like you’ve reinvented the invisible, non-breathing, permeable-to-flour dragon, and are asserting its reality. Is there a test which shows water to be XeYZn? Then in that respect it does not act like our water. Is there no such test? Then in what sense is it different from H2O?
In order for everything to work exactly the same, there essentially would have to be water, since physics would have to figure out what water could do. That being said, it could just be similar. If it models how XeYZn should behave approximately, subtracts that from how XeYZn actually behaves, and adds how H2O should behave approximately, and has some force to hold the XeYZn together, you’d have to model XeYZn to predict the future.
Come to think of it, it would probably be more accurate to say that water is made of physics at this point, since it’s really more about how physics are acting crazy at that point than it is about the arrangement of protons, neutrons, and electrons. In any case, it’s not H2O.
You didn’t answer the question. Does XYZ behave like water in every way, or not? If it does, what’s the difference? If it doesn’t, you can no longer say it replaces water.
Is the thrust of the thought experiment preserved if we assume that the two versions of water differ on a chemical level, but magically act identically on the macro scale, and in fact are identical except to certain tests that are, conveniently, beyond the technological knowledge of the time period? (Assuming we are allowed to set the thought experiment in the past.)
Surely it’s not necessary that the two worlds be completely indistinguishable?
It doesn’t behave just like water. It behaves like a simpler model of water. If you look more closely, the difference isn’t what you’d expect between a good model of water and a bad model of water. It’s what you’d expect between a good model of XeYZn and a bad model of XeYZn.
In other words, it would act like water to a first approximation, but instead of adding the terms you’d expect to make it more accurate, you add the terms you’d use to make an approximation of XeYZn more accurate.
You say:
But this is clearly false: Demonstrably, xenon does not act as it does in our universe. In particular, it forms a compund with yttrium and zinc. Likewise, zinc is clearly different from our-universe zinc, which absolutely does not form compounds with xenon.
Never mind the water, or the XeYZn compound. In our universe, if you leave elemental xenon, yttrium, and zinc in a box together, they will not form a compund. That’s not true in the other universe, or how does XeYZn form in the first place? And incidentally, what about other-universe hydrogen and oxygen, do they no longer bond to form water?
When hydrogen and oxygen are combined, it causes a bizarre nuclear reaction that results in XeYZn.
Well, that breaks conservation of energy right there, so now you’ve got a really bizarre set of laws. What happens when you run electricity through water? In our universe this results in hydrogen and oxygen.
I really don’t think you can save this thought experiment; the laws of physics are too intimately interconnected.
Yes. I thought I was pretty clear on that. Breaking conservation of energy is barely touching how bizarre it is. It still acts like our universe, except where H20 and XeYZn are concerned.
If you run electricity through XeYZn, it results in hydrogen and oxygen. If you even have H20, it will immediately turn into zenon, yttrium, and zinc.
Ok. You are talking about Omega constantly intervening to make things behave as they do in our universe. But in that case, what is the sense in which XYZ is not, in fact, H2O? How do the twin-universe people know that it is in fact XeYZn? Indeed, how do we know that our H2O isn’t, in fact, XeYZn? It looks to me like you’ve reinvented the invisible, non-breathing, permeable-to-flour dragon, and are asserting its reality. Is there a test which shows water to be XeYZn? Then in that respect it does not act like our water. Is there no such test? Then in what sense is it different from H2O?
In order for everything to work exactly the same, there essentially would have to be water, since physics would have to figure out what water could do. That being said, it could just be similar. If it models how XeYZn should behave approximately, subtracts that from how XeYZn actually behaves, and adds how H2O should behave approximately, and has some force to hold the XeYZn together, you’d have to model XeYZn to predict the future.
Come to think of it, it would probably be more accurate to say that water is made of physics at this point, since it’s really more about how physics are acting crazy at that point than it is about the arrangement of protons, neutrons, and electrons. In any case, it’s not H2O.
You didn’t answer the question. Does XYZ behave like water in every way, or not? If it does, what’s the difference? If it doesn’t, you can no longer say it replaces water.
Is the thrust of the thought experiment preserved if we assume that the two versions of water differ on a chemical level, but magically act identically on the macro scale, and in fact are identical except to certain tests that are, conveniently, beyond the technological knowledge of the time period? (Assuming we are allowed to set the thought experiment in the past.)
Surely it’s not necessary that the two worlds be completely indistinguishable?
It doesn’t behave just like water. It behaves like a simpler model of water. If you look more closely, the difference isn’t what you’d expect between a good model of water and a bad model of water. It’s what you’d expect between a good model of XeYZn and a bad model of XeYZn.
In other words, it would act like water to a first approximation, but instead of adding the terms you’d expect to make it more accurate, you add the terms you’d use to make an approximation of XeYZn more accurate.