Still, it seems that you remain secure about the concepts that I’m doubting play a role under some considerations do play a role.
Not sure what you mean here.
If you are secure about the role that “existence” plays in moral discussion, please clarify it.
I prefer not to use the term “existence” at all, people have an intuitive idea of what it means, but they tend to disagree a lot when trying to formalize it.
One way of doing that is by describing a function where on one axis you have different theories about many-worlds as the ones I described in my previous post, and in the other axis you have what exists given our epistemic evidence if that theory turns out to be correct.
I don’t find the notion of many worlds useful at all, so your suggested description does not work for me. The closest I come to many worlds is the decision-theoretic “possible worlds”, i.e potential outcomes resulting from one’s potential actions, over which one either computes some sort of utility function or to which one applies deontological shortcuts. This explicitly excludes all the imaginable worlds you have no influence over, such as the “far worlds” you seem to be preoccupied with.
Fair enough. So basically if my post was trying to immunize readers, you’d be immune already.
I agree that people should refrain from using the word ‘existence’. If they are many worlds supporters, I think they still need some work done, that the concept of existence was attempting to do, but I claimed here fails to.
If, like you, they are not many-world supporters, then ‘existence’ only means causally connected to me. And the word can be avoided without paying any price by saying its equivalent.
I’m confused. From your posts I get an impression that you take “existence of many worlds” seriously, yet from your comments it seems like you don’t give this untestable much credence. Which is it?
I see. I’m not sure whether one can tell which concepts break once you subscribe that “anything is possible”, which is basically what multiverse many worlds is about.
“anything is possible”, which is basically what multiverse many worlds is about.
Can you expand on that? I’m no sort of expert, and I’ve never been entirely clear why I should care, but that said I’ve always understood MWI to be about “everything possible is actual,” and not “anything is possible.”
You are right, MWI is about “everything possible is actual [somewhere]”. “Anything is possible” is one of the conclusions of the pseudo-scientific Tegmarkery. (It qualifies as pseudo-science because of its unfalsifiability.)
But let’s take the MWI proper and see where it leads us. Take a simple example of radioactive decay. A nucleus has a constant decay rate, and so there is an equal chance of detecting the decay between time t and t+dt for any t. They are all equally possible outcomes. From the MWI postulate it follows that they are all actual outcomes somewhere. (Here I am simplifying the situation somewhat, every possible combination, as well as magnitude and direction of the decay products’ momenta corresponds to a separate outcome and hence a separate world.)
This means that there are infinitely many worlds where the Sun (or the Earth) spontaneously exploded due to all its decayable nuclei decaying at the same time. Admittedly, these words, though uncountably infinitely many of them there may be, are probably a set of measure zero among all the possibilities, though, not being a mathematician, I am not at all sure how some uncountable infinities can be smaller than others.
Now, if you allow outcomes like that, it is only a small step to constructing a world with nearly arbitrary properties. You want unlimited power? Find a possible world where atmospheric hydrogen spontaneously fuses in just the right way in just the right place to give you all the energy you need. No laws of physics are violated. You want to shoot laser beams from your eyes? There is a tiny chance of level inversion and stimulated emission at any non-zero temperature. And so on. Almost any techno-babble can be actualized in infinitely many of the Many Worlds, if you construct them carefully enough.
You are right, MWI is about “everything possible is actual [somewhere]”.
Cool, that’s what I thought.
Almost any techno-babble can be actualized in infinitely many of the Many Worlds, if you construct them carefully enough.
Sure. If anything possible is actual, then highly implausible possible states are actual, including highly implausible possible states I would really really like to be in, but am not. But, again: why should I care? What difference does it make?
“Anything is possible” is one of the conclusions of the pseudo-scientific Tegmarkery.
Again… really? I’m even less of a Tegmark expert than I am an MWI expert, which is saying something, but my understanding of Tegmark is more “even impossible things are actual.”
Beats me, I don’t care. But people here seriously discuss various incarnations of the many-worlds ideas as if their actuality made any difference in this world.
“Anything is possible” is one of the conclusions of the pseudo-scientific Tegmarkery.
Again… really? I’m even less of a Tegmark expert than I am an MWI expert, which is saying something, but my understanding of Tegmark is more “even impossible things are actual.”
What’s the difference between “anything is possible (and therefore actual)” and “even impossible things are actual.”?
From wiki: Tegmark elaborates the mathematical universe hypothesis (MUH, a.k.a. “Ultimate Ensemble”) into the Computable Universe Hypothesis (CUH), which posits that all computable mathematical structures exist.
We can conclude that “anything that isn’t disallowed, using our current model of physics” is only a subset of “anything that can be described using any arbitrary computable mathematical structure”.
people here seriously discuss various incarnations of the many-worlds ideas as if their actuality made any difference in this world.
Yeah, I’ve noticed that.
It seems harmless enough, and I share a narrative preference for “observers behave just like everything else” over “observers somehow collapse wavefunctions” just because I prefer explanations where the observer isn’t special, but I’ve never understood what difference it’s supposed to make.
I mean, if it were theoretically possible under MWI to mine other Worlds for energy, as you seem to suggest above, then I could understand caring… but as I understand it, MWI doesn’t allow for that, any more than non-MWI allows for mining hypothetical worlds for energy.
That said, if someone argues X and I think X doesn’t matter, it’s silly to argue NOT X rather than ask “OK, what follows? Why should I care?”
What’s the difference between “anything is possible (and therefore actual)” and “even impossible things are actual.”?
Well, the former asserts a dependency between actuality and possibility, the latter denies any such dependency. Why should I care, you ask? No reason I can think of. I understand why I’m supposed to care about Tegmark even less than I understand why I’m supposed to care about MWI.
I mean, if it were theoretically possible under MWI to mine other Worlds for energy, as you seem to suggest above
Uh, I most emphatically don’t suggest anything like that, I was simply mentioning that among possible worlds there are some convenient ones where what you need is always available for you.
That said, if someone argues X and I think X doesn’t matter, it’s silly to argue NOT X rather than ask “OK, what follows? Why should I care?”
I agree, but it’s not silly to point out that it’s silly to argue X if it makes no instrumental difference whether X is true.
among possible worlds there are some convenient ones where what you need is always available for you.
If “you” means me, or anyone else able to read your post, (which is what I thought you meant, hence the “mining” reference) then this simply isn’t true under MWI. If not, can you clarify what “you” means here?
Huh. Well, I certainly agree that under MWI someone in the most convenient world has access to the resources of the world they live in. (And, again, I don’t really care.)
I see no reason to call that person “me,” though, except in the broad sense in which I can identify with people similar to me. Though I doubt there’s anyone in that most-convenient-world who resembles me as much as, for example, you (by which I mean, y’know, you) do.
Though I doubt there’s anyone in that most-convenient-world who resembles me as much as, for example, you (by which I mean, y’know, you) do
Eh, it looks like we largely agree, so there is no point in further discussing this particular untestable. And given the downvotes I get in this thread, apparently others don’t want it to continue, either. Tapping out.
Not sure what you mean here.
I prefer not to use the term “existence” at all, people have an intuitive idea of what it means, but they tend to disagree a lot when trying to formalize it.
I don’t find the notion of many worlds useful at all, so your suggested description does not work for me. The closest I come to many worlds is the decision-theoretic “possible worlds”, i.e potential outcomes resulting from one’s potential actions, over which one either computes some sort of utility function or to which one applies deontological shortcuts. This explicitly excludes all the imaginable worlds you have no influence over, such as the “far worlds” you seem to be preoccupied with.
Fair enough. So basically if my post was trying to immunize readers, you’d be immune already.
I agree that people should refrain from using the word ‘existence’. If they are many worlds supporters, I think they still need some work done, that the concept of existence was attempting to do, but I claimed here fails to.
If, like you, they are not many-world supporters, then ‘existence’ only means causally connected to me. And the word can be avoided without paying any price by saying its equivalent.
I’m confused. From your posts I get an impression that you take “existence of many worlds” seriously, yet from your comments it seems like you don’t give this untestable much credence. Which is it?
The latter, which I was clarifying in an edit to the original post as you asked.
I still think it is productive to instrumentally talk of Many Worlds, to see which concepts break.
I see. I’m not sure whether one can tell which concepts break once you subscribe that “anything is possible”, which is basically what multiverse many worlds is about.
Can you expand on that? I’m no sort of expert, and I’ve never been entirely clear why I should care, but that said I’ve always understood MWI to be about “everything possible is actual,” and not “anything is possible.”
You are right, MWI is about “everything possible is actual [somewhere]”. “Anything is possible” is one of the conclusions of the pseudo-scientific Tegmarkery. (It qualifies as pseudo-science because of its unfalsifiability.)
But let’s take the MWI proper and see where it leads us. Take a simple example of radioactive decay. A nucleus has a constant decay rate, and so there is an equal chance of detecting the decay between time t and t+dt for any t. They are all equally possible outcomes. From the MWI postulate it follows that they are all actual outcomes somewhere. (Here I am simplifying the situation somewhat, every possible combination, as well as magnitude and direction of the decay products’ momenta corresponds to a separate outcome and hence a separate world.)
This means that there are infinitely many worlds where the Sun (or the Earth) spontaneously exploded due to all its decayable nuclei decaying at the same time. Admittedly, these words, though uncountably infinitely many of them there may be, are probably a set of measure zero among all the possibilities, though, not being a mathematician, I am not at all sure how some uncountable infinities can be smaller than others.
Now, if you allow outcomes like that, it is only a small step to constructing a world with nearly arbitrary properties. You want unlimited power? Find a possible world where atmospheric hydrogen spontaneously fuses in just the right way in just the right place to give you all the energy you need. No laws of physics are violated. You want to shoot laser beams from your eyes? There is a tiny chance of level inversion and stimulated emission at any non-zero temperature. And so on. Almost any techno-babble can be actualized in infinitely many of the Many Worlds, if you construct them carefully enough.
Cool, that’s what I thought.
Sure. If anything possible is actual, then highly implausible possible states are actual, including highly implausible possible states I would really really like to be in, but am not. But, again: why should I care? What difference does it make?
Again… really? I’m even less of a Tegmark expert than I am an MWI expert, which is saying something, but my understanding of Tegmark is more “even impossible things are actual.”
Beats me, I don’t care. But people here seriously discuss various incarnations of the many-worlds ideas as if their actuality made any difference in this world.
What’s the difference between “anything is possible (and therefore actual)” and “even impossible things are actual.”?
From wiki: Tegmark elaborates the mathematical universe hypothesis (MUH, a.k.a. “Ultimate Ensemble”) into the Computable Universe Hypothesis (CUH), which posits that all computable mathematical structures exist.
We can conclude that “anything that isn’t disallowed, using our current model of physics” is only a subset of “anything that can be described using any arbitrary computable mathematical structure”.
Yeah, I’ve noticed that.
It seems harmless enough, and I share a narrative preference for “observers behave just like everything else” over “observers somehow collapse wavefunctions” just because I prefer explanations where the observer isn’t special, but I’ve never understood what difference it’s supposed to make.
I mean, if it were theoretically possible under MWI to mine other Worlds for energy, as you seem to suggest above, then I could understand caring… but as I understand it, MWI doesn’t allow for that, any more than non-MWI allows for mining hypothetical worlds for energy.
That said, if someone argues X and I think X doesn’t matter, it’s silly to argue NOT X rather than ask “OK, what follows? Why should I care?”
Well, the former asserts a dependency between actuality and possibility, the latter denies any such dependency. Why should I care, you ask? No reason I can think of. I understand why I’m supposed to care about Tegmark even less than I understand why I’m supposed to care about MWI.
Uh, I most emphatically don’t suggest anything like that, I was simply mentioning that among possible worlds there are some convenient ones where what you need is always available for you.
I agree, but it’s not silly to point out that it’s silly to argue X if it makes no instrumental difference whether X is true.
If “you” means me, or anyone else able to read your post, (which is what I thought you meant, hence the “mining” reference) then this simply isn’t true under MWI.
If not, can you clarify what “you” means here?
Someone in this most convenient world.
Huh. Well, I certainly agree that under MWI someone in the most convenient world has access to the resources of the world they live in. (And, again, I don’t really care.)
I see no reason to call that person “me,” though, except in the broad sense in which I can identify with people similar to me. Though I doubt there’s anyone in that most-convenient-world who resembles me as much as, for example, you (by which I mean, y’know, you) do.
Eh, it looks like we largely agree, so there is no point in further discussing this particular untestable. And given the downvotes I get in this thread, apparently others don’t want it to continue, either. Tapping out.