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A comment on The computers are fast, but you don't know it. Parent comment

Re:The computers are fast, but you don't know it by somenameforme on Friday June 17, 2022 @02:12AM (#31774627)
The much more remarkable thing is to consider that that speed of light is also the speed of causality itself. It takes light from the sun about 8 minutes to reach Earth. If the sun suddenly disappeared, we'd still see it shining brightly in the sky, and the Earth would continue revolving around it - all for another 8 minutes until reality finally caught up to us. So we're already computing at a rate on the verge of the speed of reality itself.

It's interesting to consider this paired against how technologically primitive we ostensibly must be, given that digital computers didn't even exist 90 years ago.

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Re:The computers are fast, but you don't know it by CMCDragonkai on Friday June 17, 2022 @02:21AM (#31774689)
Is the speed of light really the speed of causality? Would the effect of gravity (the lack of) affect Earth earlier than us perceiving the lack of light.
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Re:The computers are fast, but you don't know it by d110af5ccf on Friday June 17, 2022 @02:26AM (#31774722)
Nope. All physical effects are bounded by the speed of light. (As far as anyone knows, anyway.)

The only weird one is quantum entanglement, but even then information transfer doesn't travel faster than light and that's about all I know on that subject.

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Re:The computers are fast, but you don't know it by rl3 on Friday June 17, 2022 @02:41AM (#31774817)
>The only weird one is quantum entanglement, but even then information transfer doesn't travel faster than light ...

For anyone wondering why that is, I found this explanation super interesting:

https://www.forbes.com/sites/startswithabang/2020/01/02/no-w...

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Re:The computers are fast, but you don't know it by drewtato on Friday June 17, 2022 @03:51AM (#31775303)
I also liked this explanation: https://www.youtube.com/watch?v=v7jctqKsUMA

In short, the only information you gain is about the outcome of the other side's measurement. They cannot introduce information into the particle, and thus can't transmit information. The only thing you learn is what you already knew: the other particle had a 50% chance of being in one state or another, with the added fact that it's now correlated to your particle with a 75% (depending on experiment) chance. This is information that didn't exist until that moment, so it couldn't have been sent out and reach you before you measure your particle, which would inform you with 75% certainty how your particle would act and break causality.

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Re:The computers are fast, but you don't know it by dorgo on Friday June 17, 2022 @01:13PM (#31781235)
> All physical effects are bounded by the speed of light.

The universe expands faster than light. So this expansion is not a physical effect?

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Re:The computers are fast, but you don't know it by orestarod on Monday June 20, 2022 @07:23AM (#31808965)
The universe expanding is a property of space itself. And "faster than light" is only because miniscule space expansion in any quantum of space adds up with distance, e.g. 1 picometer per kilometer per second, add enough trillions of kilometers and you get that faster than light expansion. There is no mass, particle or information moving THROUGH space faster than the speed of light, which is what the said limit concerns.
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Re:The computers are fast, but you don't know it by saberience on Friday June 17, 2022 @04:42AM (#31775609)
Why does gravity travel at the speed of light?
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Re:The computers are fast, but you don't know it by rieTohgh6 on Friday June 17, 2022 @05:57AM (#31776074)
Well the other way to look at it is: gravity travels at maximum possible speed in this universe. Light in vacuum can also reach same maximum speed. I guess we would say the light travels with speed of gravity if we measured them in other order.
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Re:The computers are fast, but you don't know it by e63f67dd-065b on Friday June 17, 2022 @02:26AM (#31774724)
The speed of light is the speed of information propagation. Information about the sun disappearing would only reach earth at after c/1AU.
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Re:The computers are fast, but you don't know it by HWR_14 on Friday June 17, 2022 @02:39AM (#31774804)
The change in gravitational force also propagates at the speed of light. It's weird.
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