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A delightful quirk of relativity theory

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Re: A delightful quirk of relativity theory

#51

Post by ctw »

jahnu wrote: post #43
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…

> "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 through time at one second per second, but since people are in motion relative to each other and therefore have different frames of reference, their clocks will measure different times.

Since no frame of reference is privileged, there is no “absolute time”. Of course you could pick one and measure every event against that one, but that would be an arbitrary choice.

This is my understanding. If I’m wrong, I’d be happy to be corrected.

Re: A delightful quirk of relativity theory

#52

Post by cropcirclbureau »

naasking wrote: post #39
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…

> "The more you move in space, the less you move in time." Even better IMO: everything is moving at the max speed (c) through spacetime, and accelerating along one dimension means decelerating along other dimensions; for example, stationary objects have 0 speed in spatial dimensions but move at c through time, and photons move at c through space but are stationary along the time dimension.

Yeah, the video [0] by Fermilab that taught me this explanation blew my mind.

[0] https://www.youtube.com/watch?v=A2JCoIGyGxc&list=LL&index=94

Re: A delightful quirk of relativity theory

#53

Post by vidarh »

V-2 wrote: post #44
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…

The typical source of confusion is conflating "free" with "unpredictable". But they're not the same thing at all.

"Unpredictable" is imprecise to the point of being meaningless.

If a black box is fully deterministic to the point that you can construct a model that is entirely accurate, then there's nothing "free" about it. What you're modelling has no agency. For the notion of "free will" to have any meaning at all, it doesn't need to be "unpredictable" in the sense that it keeps confounding someone trying to predict it all the time, but it does need to deviate from predictions sometimes or you have just an automaton, and it needs to do so in a way that is fundamentally impossible to model, and it needs to do so without just injecting randomness.

I've yet to see anyone present a definition of "free will" that doesn't reduce to smoke and mirrors, because that would mean coming up with some fourth category in a venn diagram of determinism, randomness and the combination of the two where they intersect, that is non-deterministic in a way that can't be explained by layering a deterministic model and randomness.

Re: A delightful quirk of relativity theory

#54

Post by vidarh »

Guessnotgauss wrote: post #50
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…

How about, the fact you can even argue that free will exists is a demonstration of it.

Creating something that can argue that free will exists requires an eliza-level chatbot, nothing more.

Re: A delightful quirk of relativity theory

#55

Post by derbOac »

soneca wrote: post #12
enriquto wrote: post #4

I love the name of the scientist Al Unapietra. The thing is very well explained, but it's very sad to see it as a twitter thread, which is a mostly unreadable format.

Twitter threads don’t bother me. The brain quickly adapts to skipping the irrelevant parts (username, like buttons, etc) and to expecting the cadency of tweets. I believe it is harder to write (due to the character limit of each text block), but, far from “unreadable”, I can read it fairly easily.

I tune out after a certain point with these types of long Twitter threads. It's like reading a magazine conveyed via telegraph.

People are correct to point out it helps material reach a wide audience, but that's not the point. The point is what could be better?

The original argument was to keep communication brief, shorter is better, etc. The fact it keeps being circumvented in this way suggests sometimes a longer format is necessary.

As a practical matter, in this case the person could have linked to a long form blog post and used Twitter as a sort of comment discussion section?

Re: A delightful quirk of relativity theory

#56

Post by stared »

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…

A real paradox is if you can reach two mutually-exclusive conclusions. In the special relativity theory, the order of events depends on the frame of reference. It is not much unlike 2D space if something is left or right to each other depending on a rotation.

"I don't like how does the special relativity/quantum physics works" is not a paradox on its own. In this case, it just challenges our pedestrian view of time.

Re: A delightful quirk of relativity theory

#57

Post by prmph »

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…

Well free does not exist only if logic is bound by what the human mind can conceive. It may be possible for something not be random, and to have no antecedent at the same time.

Also, the concept of free will is bound up with the concept of consciousness. What is the entity that may or may not have free will? Until we define and understand that, free will will be an ill-defined concept not amenable to proper analysis

Re: A delightful quirk of relativity theory

#58

Post by plucas »

Thomashuet wrote: post #7

More readable formatting: https://threadreaderapp.com/thread/1482811504424542211.html

Note that Thread Reader loses the images attached to some of the tweets (at least for me).

Edit: strike that, it was Firefox's social tracker protection blocking them. Just need to click the shield icon left of the address bar and temporarily disable it.

Re: A delightful quirk of relativity theory

#59

Post by michalf6 »

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…

>call it free if the choice is not computable in advance

Is it not essentially equivalent to "actual" free will? I am perfectly happy with just this.

Re: A delightful quirk of relativity theory

#60

Post by coliveira »

Guessnotgauss wrote: post #50
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…

How about, the fact you can even argue that free will exists is a demonstration of it.

I can think of a world without free will too. And I can imagine a large amount of things that don't exist.
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