So you meant something like “counterfactually, it’s more likely that Steve Jobs changed his mind about treatment than it is that he didn’t get pancreatic cancer.”
Indeed, I’m beginning to see that alternatives that are counterfactually likely have perhaps no relationship with nearby Everett branches. For example, ‘if I didn’t become a chemist I probably would have been a biologist’ may be true but nevertheless might have nothing to say about how near the two possibilities are in terms of quantum states.
A few interesting hypotheses have occurred to me that I’d like to think about more, but right now I’m a little confused about how two nearby Everett branches would look. What would the first divergence look like?
Most of what we experience is classical, and thus an averaged process of zillions of quantum states. Thus seeing anything different would require a huge statistical anomaly. For example, it’s theoretically possible that a teacup will start floating on a table but it would be very unlikely and it’s kind of hard to believe in. Is this the kind of thing to expect in any nearby Everett branch that actually looks different?
So now that I know i’m looking for a locally concentrated statistical anomaly—rather than a scattering of changed states here or there—this directs me to consider weird/unlikely events at the molecular level.
So for example, in nearby Everett branches it is relatively near for someone to not be born (since presumably a smaller number of molecular events are required for a particular conception) but given that they’re born, not near for them to make a different decision at a certain point in time because presumably many molecular interactions are averaged to form decisions.
So: easy for Steve Jobs to not be here, but difficult for him to make a different decision. However, Steve Jobs being born or Steve Jobs not being born result in very different universes.
I’m thinking that once you add ‘causality’ to the mix, there very little reason nearby Everett branches will look like one another, from our point of view. That is, if the differences are large enough for us to notice, the results could just as likely be huge as inconsequential.
I feel confused and wonder if someone has already dissolved this?
One problem may be that you are not taking time evolution into account. Steve Jobs not being born and Steve Jobs being born are similar at conception. But because life is great at turning small changes into bigger changes, once the ovum starts replicating they can be quite far apart, and of course many years later there are huge differences :)
It’s like chaos theory and predicting the weather—states might start out close together, but even tiny differences can give you totally different futures, because the difference can grow exponentially.
Nearby Everett branches will indeed look like one another. Right now, we’re pretty far away from “no steve jobs” universe. But we were close in the past, which gives it that nice “alternate universe” feel.
And yeah, welcome to the wild world of infinite-dimensional spaces.
I started to form a counterargument and then realized that I had a really different (and unjustified) model of what was going on. Suppose one quantum state is different in one branch compared to another. This one state being different creates a ripple effect of new interactions that happen in that branch that can not happen in the second branch. Thus over time, the branches increasingly diverge in the similarity of their quantum states.
This updates my view, which was imagining a particular Everett branch as a 4 dimensional “matrix” of random numbers, each number representing the chosen quantum state of quantum at that location in space time. I thought you could then find nearby Everett branches by just changing a number at just one position in that matrix. In this model, you could have two Everett branches very near one another in which Steve Jobs was born and one in which he wasn’t just by changing an area of values around the time and place of his conception. The two matrices would appear very different even though their quantum states were identical except in one small area of space time. I see now that I had thought of space time as discretized, quantum states were assigned to each discrete unit in a regular way, and the states were just read off as if from a tape, so that the tape could be the same before and after a perturbation. Instead, perturbations change the reading of the tape exponentially as time progresses.
Time is really important with this other view.
And yeah, welcome to the wild world of infinite-dimensional spaces.
(this comment written after this one)
Indeed, I’m beginning to see that alternatives that are counterfactually likely have perhaps no relationship with nearby Everett branches. For example, ‘if I didn’t become a chemist I probably would have been a biologist’ may be true but nevertheless might have nothing to say about how near the two possibilities are in terms of quantum states.
A few interesting hypotheses have occurred to me that I’d like to think about more, but right now I’m a little confused about how two nearby Everett branches would look. What would the first divergence look like?
Most of what we experience is classical, and thus an averaged process of zillions of quantum states. Thus seeing anything different would require a huge statistical anomaly. For example, it’s theoretically possible that a teacup will start floating on a table but it would be very unlikely and it’s kind of hard to believe in. Is this the kind of thing to expect in any nearby Everett branch that actually looks different?
So now that I know i’m looking for a locally concentrated statistical anomaly—rather than a scattering of changed states here or there—this directs me to consider weird/unlikely events at the molecular level.
So for example, in nearby Everett branches it is relatively near for someone to not be born (since presumably a smaller number of molecular events are required for a particular conception) but given that they’re born, not near for them to make a different decision at a certain point in time because presumably many molecular interactions are averaged to form decisions.
So: easy for Steve Jobs to not be here, but difficult for him to make a different decision. However, Steve Jobs being born or Steve Jobs not being born result in very different universes.
I’m thinking that once you add ‘causality’ to the mix, there very little reason nearby Everett branches will look like one another, from our point of view. That is, if the differences are large enough for us to notice, the results could just as likely be huge as inconsequential.
I feel confused and wonder if someone has already dissolved this?
One problem may be that you are not taking time evolution into account. Steve Jobs not being born and Steve Jobs being born are similar at conception. But because life is great at turning small changes into bigger changes, once the ovum starts replicating they can be quite far apart, and of course many years later there are huge differences :)
It’s like chaos theory and predicting the weather—states might start out close together, but even tiny differences can give you totally different futures, because the difference can grow exponentially.
Nearby Everett branches will indeed look like one another. Right now, we’re pretty far away from “no steve jobs” universe. But we were close in the past, which gives it that nice “alternate universe” feel.
And yeah, welcome to the wild world of infinite-dimensional spaces.
I started to form a counterargument and then realized that I had a really different (and unjustified) model of what was going on. Suppose one quantum state is different in one branch compared to another. This one state being different creates a ripple effect of new interactions that happen in that branch that can not happen in the second branch. Thus over time, the branches increasingly diverge in the similarity of their quantum states.
This updates my view, which was imagining a particular Everett branch as a 4 dimensional “matrix” of random numbers, each number representing the chosen quantum state of quantum at that location in space time. I thought you could then find nearby Everett branches by just changing a number at just one position in that matrix. In this model, you could have two Everett branches very near one another in which Steve Jobs was born and one in which he wasn’t just by changing an area of values around the time and place of his conception. The two matrices would appear very different even though their quantum states were identical except in one small area of space time. I see now that I had thought of space time as discretized, quantum states were assigned to each discrete unit in a regular way, and the states were just read off as if from a tape, so that the tape could be the same before and after a perturbation. Instead, perturbations change the reading of the tape exponentially as time progresses.
Time is really important with this other view.
Thanks