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A delightful quirk of relativity theory

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Re: A delightful quirk of relativity theory

#131

Post by tsimionescu »

awb wrote: post #78
danbruc wrote: post #42

Earlier quoted context omitted.

Rescuing free-will from the jaws of spacetime would be cool! Free will does not exist. It is logically inconsistent. Either your choice is some function of your current state and the environment you are in, then the choice is not free, or it is independent of your current state and the environment you are in, then it is not your choice in any meaningful way, it is just the result of a coin flip. You can do some menta…

A few issues with the “free will” debate. 1) Define “free” 2) How do you test your hypothesis? You’re trying to apply logic to an untestable philosophical debate. If you believe free will doesn’t exist, you can’t design an experiment that would invalidate that belief. And if your theory is untestable and unfalsifiable, then what good is it other than a creative exercise? However, we do know from Quantum Mechanics tha…

> However, we do know from Quantum Mechanics that the universe is probabilistic and not deterministic:

This is not true, and there are consistent interpretations of QM that are fully deterministic (many worlds, superdeterminism, pilot wave).

Still, probabilistic vs deterministic makes no difference. There is no free will in a throw of the dice, and no free will in the wave function collapse.

On the other hand, the main philosophical position on this is compatibilism: free will in a fully deterministic universe (or probabilistic one). If you think of yourself as the sum total of all your experiences and genetics, your next action is of course determined by these; but, another agent in your shoes, one with different experiences and genetics, would make a different choice. So in this framework, your choice, even though uniquely determined by everything that happened before, and theoretically predictable 1000 years in advance, is still meaningfully "your choice".

In fact, random chance hurts this definition, and weakens the case for compatibilism; if your next action is entirely dependent on some random quantum fluctuation, and running the experiment with your exact same experience and genetics but a different random quantum event at this exact time would produce 1000 entirely different actions on your part, then it is very hard to imagine any kind of free will. So, free will actually depends on some amount of determinism. Even the type of determinism in Many Worlds would not solve this - since in that interpretation, all possible outcomes of the quantum event actually happen, so all your "choices" that depend on the random event are fully real. So, if each of the fully real copies of you, with the exact same experiences and genetics, does a wildly different thing, then it's pretty clear there is no meaningful free will in any possible sense.

Re: A delightful quirk of relativity theory

#132

Post by kybernetikos »

vidarh wrote: post #101
kybernetikos wrote: post #45

Earlier quoted context omitted.

You've put the dilemma nicely - it can't be both 'free' and 'your will' by your definitions (well, without admitting supernatural beings that can affect and be affected by the natural world, but are not part of it). Personally I'm happy with other definitions, not because I feel I'm doing mental gymnastics, but because the version you give is clearly not what normal people mean by it when they refer to it. It might w…

> Personally I'm happy with other definitions, not because I feel I'm doing mental gymnastics, but because the version you give is clearly not what normal people mean by it when they refer to it. It might well be related to what philosophers argue about, but normal people who offer you a 'free choice' or who say that you did something 'of your own free will' do not mean anything like 'your choice was not a function o…

> if you genuinely believe the notion that we have free will is nonsense (and I do), then the logical extension is to be very uncomfortable with the notion of e.g. prison used for vengeance or anything at all other than to the bare minimal extent required to protect others

Not really. You can view it as a game theoretic situation. Will the use of prison likely produce a good outcome or a bad outcome? Whether or not the criminal was deterministically required to commit the crime, the structure of punishments will (perhaps deterministically) affect the incidents and severity of future crimes.

Just because the creature in Black and White may have made decisions deterministically doesn't mean I won't punish it if it behaves in an inappropriate way. If anything, believing the agents are deterministic would make me even more keen to punish in situations where it will change behaviour usefully.

Re: A delightful quirk of relativity theory

#133

Post by danbruc »

syki wrote: post #114
danbruc wrote: post #42

Earlier quoted context omitted.

Rescuing free-will from the jaws of spacetime would be cool! Free will does not exist. It is logically inconsistent. Either your choice is some function of your current state and the environment you are in, then the choice is not free, or it is independent of your current state and the environment you are in, then it is not your choice in any meaningful way, it is just the result of a coin flip. You can do some menta…

Regarding your either/or line of reasoning in your first paragraph. Are you sure these are the only two possibilities? Could there be partial dependence on the current state of one’s mind and environment? Does the same exact state always lead to the same exact decision? That is, if a universe began exactly as ours did and everything was the same up until time t when a decision is made by someone is that decision alwa…

One can certainly also imagine a mix of both option, for example your preferences deterministically determine which options you consider but a random event determines the choice you make. But that doesn't make a big difference, it's still a mix of predetermined and random things.

A third option would have to be a wild thing - a choice would have to neither depend on the state of the universe, i.e. be determined, nor be independent of the state of the universe, i.e. be random. I personally don't see any room for a third option but there are probably a lot of things you could try to poke holes into. Is the state of the universe a meaningful concept? How does it relate to time? Does true randomness exist?

Re: A delightful quirk of relativity theory

#134

Post by pxmpxm »

irthomasthomas wrote: post #21

This would be more fun in a blog post. Twitter is a fucking horrible format for a complex analysis of special relativity. That aside, my favourite quirk from relativity is this: "The more you move in space, the less you move in time." Like relativity in general, it sounds simple enough, but it's consequences are profoundly shocking. (That is, if you take the time to understand it, and don't leap to the conclusion tha…

"This would be more fun in a blog post. Twitter is a fucking horrible format for a complex analysis of special relativity." My very first sentiment, having read the whole thing.

Re: A delightful quirk of relativity theory

#135

Post by kybernetikos »

vidarh wrote: post #130
kybernetikos wrote: post #127

Earlier quoted context omitted.

I think free will is the feeling of being a choice making agent in the absence of unreasonable external constraints. This isn't original or unique with me, and I've held this view for quite a large number of years (e.g. this comment from 6 years ago: https://news.ycombinator.com/item?id=11740316 ). It fits pretty well with what people mean when they say 'free will' or 'free choice' in normal every day life (i.e. if y…

Try probing what people think having free will actually means, and you'll quickly see that people tend to react very strongly if you suggest that they don't have some vague undefined ability to take actions that are not defined merely by the state of their brains and inputs. To me what you describe does not at all match what I've observed people try to defend as free will whenever you peer beneath the vague veneer of…

You've got some interesting points there, but I think that the reaction some people have to the idea that they might be deterministic is actually to do with dualism and not free will. People try to pull free will into the dualism debate because they are desperately looking for reasons to back up their feeling that they are essentially more than pure material. I don't think that these two topics really have much to do with each other, which I think can be seen by looking at what people really mean when they actually talk about free choice and free will in everyday life rather than in philosophical conversations where they're already trying to justify a position.

Re: A delightful quirk of relativity theory

#136

Post by _0w8t »

danbruc wrote: post #42
irthomasthomas wrote: post #21

This would be more fun in a blog post. Twitter is a fucking horrible format for a complex analysis of special relativity. That aside, my favourite quirk from relativity is this: "The more you move in space, the less you move in time." Like relativity in general, it sounds simple enough, but it's consequences are profoundly shocking. (That is, if you take the time to understand it, and don't leap to the conclusion tha…

Rescuing free-will from the jaws of spacetime would be cool! Free will does not exist. It is logically inconsistent. Either your choice is some function of your current state and the environment you are in, then the choice is not free, or it is independent of your current state and the environment you are in, then it is not your choice in any meaningful way, it is just the result of a coin flip. You can do some menta…

Free will just cannot be described by physics. This is very similar to the perception of the time flow. Time in physics is static. There is no now. Surely one can plug any time value into physical equations, but that will not explain, for example, why when we look at a thrown ball, we perceive a movement, and not, say the whole trajectory of the ball at the same time.

And given that the free will and now are connected it is easy to see why we cannot describe the free will using physical equations. Well, at least until we will manage to describe now.

Re: A delightful quirk of relativity theory

#137

Post by platz »

ctw wrote: post #51
jahnu wrote: post #43

Earlier quoted context omitted.

> "The more you move in space, the less you move in time." Isn't that missing a bit at the end? The less you appear to move in time from a different frame of reference? We all move through time at exactly 1 second per second, don't we? For reference: Here's Sean Carrol saying exactly that (but in reply to a different question) https://www.preposterousuniverse.com/podcast/2021/12/15/ama-... "...it always goes by one s…

Disclaimer: I’m interested in relativity and have been reading about it lately but I’m no authority. > We all move through time at one second per second, don’t we? You need to define “move through time”. The only way to measure time is with a clock, and the clock’s motion relative to you affects the measurement. If you let everyone define “time” as the thing measured by the watch on their wrist, then everyone moves t…

I think Sean Carroll understands Special and General Relativity.

Re: A delightful quirk of relativity theory

#139

Post by michaelcampbell »

irthomasthomas wrote: post #21

This would be more fun in a blog post. Twitter is a fucking horrible format for a complex analysis of special relativity. That aside, my favourite quirk from relativity is this: "The more you move in space, the less you move in time." Like relativity in general, it sounds simple enough, but it's consequences are profoundly shocking. (That is, if you take the time to understand it, and don't leap to the conclusion tha…

> Twitter is a fucking horrible format for...

Anything requiring more than about 350 chars, IMO. I'm really interested in that thread, but gave up after 5-6 tweets. My loss, I guess.

Re: A delightful quirk of relativity theory

#140

Post by gfody »

time_to_smile wrote: post #112
whatshisface wrote: post #106

Earlier quoted context omitted.

The difference between quickly getting to a point where you can't forecast the weather, and the fact that you can't predict wavefunction collapse at all, is significant on a more than metaphysical level. Figuring out which bucket human beings fall in to is a legitimate question.

> the weather > wavefunction Which of these are commonly accepted (or even argued by a sizable minority) to have free will in a metaphysical sense? > Figuring out which bucket human beings fall in to is a legitimate question. That may be true, but it doesn't seem like it has anything to do with the ill-defined notion of "free will". I'm also not familiar with anyone who views human behavior to be anything like a coll…

> Which of these are commonly accepted (or even argued by a sizable minority) to have free will in a metaphysical sense?

both, see the free will theorem from Conway and Kochen

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