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Puzzling thing about Speed of Light/Speed of Causality
August 24, 2018 at 3:31 am
(This post was last modified: August 24, 2018 at 3:53 am by vulcanlogician.)
So this is a perplexing thought experiment I found online.
The sun is approximately eight "light minutes" away. This means that if the sun were suddenly to go dark, we on Earth would not become aware of it until eight minutes after the fact. Most of us are familiar with this aspect of the speed of light.
Now here's the weird thing: the speed of light is also the speed of causality. And the implications of this are semi-paradoxal (at least to me). In any case, it seems to defy my intuitions about how time and causality work.
This thought experiment demonstrates the part that I consider paradoxal:
Let's say there is a light switch, floating beside the sun, that can turn the sun on and off. If somebody flips the sun off, it would take us eight minutes to realize on Earth that the sun had been turned off (just as I said in the beginning of the post). Now, suppose you had a stick that stretched all the way from the Earth to the sun and you used the stick to hit the switch and turn off the sun. From the moment you thrusted the stick to flip the switch, how long would it take for you (on Earth) to see the sun go out?
The answer is: approximately 16 minutes. Why? Because, the speed of light is the speed of causality. It takes eight minutes for a cause on Earth to become an effect on the light switch that is floating beside the sun. So it would take 8 minutes for the other end of the stick to be affected by your thrust from earth, then it would take 8 more minutes for you to realize the sun had actually gone out.
Doesn't this seem counterintuitive? It seems like it should only take eight minutes to see the sun go out because the other end of the stick would only have to travel a few centimeters. But that is not the case.
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RE: Puzzling thing about Speed of Light/Speed of Causality
August 24, 2018 at 3:36 am
It's all really weird. It sounds to me suspiciously like a simulation with processing power limitations.
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RE: Puzzling thing about Speed of Light/Speed of Causality
August 24, 2018 at 3:50 am
(August 24, 2018 at 3:36 am)robvalue Wrote: It's all really weird. It sounds to me suspiciously like a simulation with processing power limitations.
What is your opinion of the simulation hypothesis?
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RE: Puzzling thing about Speed of Light/Speed of Causality
August 24, 2018 at 4:03 am
(August 24, 2018 at 3:50 am)vulcanlogician Wrote: (August 24, 2018 at 3:36 am)robvalue Wrote: It's all really weird. It sounds to me suspiciously like a simulation with processing power limitations.
What is your opinion of the simulation hypothesis?
Do you mean the one based on probability? I found it initially quite compelling but on closer inspection it makes too many assumptions for my liking and seems a bit circular.
I am however totally undecided on whether or not we're living in a simulation. Ironically, I am very likely to be living in one, if we assume something exists outside of my consciousness. I'm living in my own virtual reality created by my brain.
One of the conclusions I've come to in my philosophical thinking is that defining what "real" means in a non-circular way is problematic at best and impossible at worst.
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RE: Puzzling thing about Speed of Light/Speed of Causality
August 24, 2018 at 4:41 am
(This post was last modified: August 24, 2018 at 4:50 am by vulcanlogician.)
(August 24, 2018 at 4:03 am)robvalue Wrote: One of the conclusions I've come to in my philosophical thinking is that defining what "real" means in a non-circular way is problematic at best and impossible at worst.
Hmmmm... that does seem like a toughie. Maybe it would be easier to outline what reality is not. For instance, not illusory, imaginary, or the product of deceit.
As to the simulation hypothesis, that's an interesting thing to ponder. I am inclined to think that things are too weird to be the product of a simulation. I consider it to be a (very remote) possibility. That's why I said I was a 6/7 on the Dawkins scale in the other thread. If I'm not completely sold on the fact I'm not a brain in a vat, I can't be a 7/7. I mean, if it turns out I'm a brain in a vat, all bets are off, y'know?
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RE: Puzzling thing about Speed of Light/Speed of Causality
August 24, 2018 at 5:10 am
(This post was last modified: August 24, 2018 at 5:11 am by ignoramus.)
And what difference, for all intents and purpose would it make if we did discover we are all brains in vats, or a product of someone's dream or in a sim?
I still have to go to work tomorrow? Other sim people are relying on me? My letting them down may not be real but the mental pain I'm imagining appears real
I've since matured a lot after being here a few years. I've abandoned all alternate theories to explain things/the universe, etc.
You know, once meme hit home with me. It said (to paraphrase), We create conspiracy theories about who's really in control because we find comfort knowing someone or something has control. In stark reality, the answer is a lot scarier! Because nothing and no-one has ever been in control. Earth's evolution has always been guided by brute military force and organized chaos.
I accept that now. I'm comfortable with it.
No God, No fear.
Know God, Know fear.
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RE: Puzzling thing about Speed of Light/Speed of Causality
August 24, 2018 at 5:11 am
(August 24, 2018 at 3:31 am)vulcanlogician Wrote: Doesn't this seem counterintuitive? It seems like it should only take eight minutes to see the sun go out because the other end of the stick would only have to travel a few centimeters. But that is not the case.
I think the problem is that you are thinking of it in discrete steps. As in push on stick, light goes off. Whereas in reality there would be pressure applied to one end of the stick which then tries to equalise and moves the position of the atoms in space along the stick until it reaches the light switch. Or something like that, I am not a physicist. Maybe it's easier to think of it instead as an electrical signal sent over a wire to the light switch at the sun rather than a stick. The electrons would then take 8 minutes to move along it before the sun could be turned off.
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RE: Puzzling thing about Speed of Light/Speed of Causality
August 24, 2018 at 5:17 am
(This post was last modified: August 24, 2018 at 5:18 am by ignoramus.)
Good point Mat. I can understand the 16 minutes easier now.
But what if we had an entangled switch!
No God, No fear.
Know God, Know fear.
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RE: Puzzling thing about Speed of Light/Speed of Causality
August 24, 2018 at 5:29 am
(This post was last modified: August 24, 2018 at 5:36 am by I_am_not_mafia.)
I think the biggest indicator that we aren't living in a simulation is the fact that the further away we look, or at the smaller scle, we find more detail. Progress in science is limited by our ability to measure. If we were living in a simulation then it has worked consistently since we were small mammals staring up at a night sky with stars, to creating the first telescopes and determining that some stars were planets, to determining that some were galaxies, sticking a telescope in space and finding yet more galaxies in what looked like an empty region of space, to measuring the rate of expansion of the universe and mapping the background cosmic radiation. Add to that other ways of measuring the cosmos with radio interferometry and measuring the flexing of spacetime itself. On the other end we've created microcopes, digital cameras that can read single photons, microscopes that can use X-rays, magnetic fields, electrons to particle accelerators to probe at a sub-atomic level. And from one end of the scale to the other it has led to a consistent level of reality.
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RE: Puzzling thing about Speed of Light/Speed of Causality
August 24, 2018 at 5:45 am
(August 24, 2018 at 5:10 am)ignoramus Wrote: And what difference, for all intents and purpose would it make if we did discover we are all brains in vats, or a product of someone's dream or in a sim?
I still have to go to work tomorrow? Other sim people are relying on me? My letting them down may not be real but the mental pain I'm imagining appears real
I've since matured a lot after being here a few years. I've abandoned all alternate theories to explain things/the universe, etc.
You know, once meme hit home with me. It said (to paraphrase), We create conspiracy theories about who's really in control because we find comfort knowing someone or something has control. In stark reality, the answer is a lot scarier! Because nothing and no-one has ever been in control. Earth's evolution has always been guided by brute military force and organized chaos.
I accept that now. I'm comfortable with it.
I agree, it doesn't make any practical difference. We are left to experience our experiences, whatever the cause may be.
I happened to watch a video about this kind of thing yesterday. I found it extremely interesting.
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