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I have heard that the speed of light can be thought of as the speed of information i.e. no information in the universe can travel faster than the speed at which massless objects go. What does "information" mean in this sense?

Thought experiment: Let's say I have a red sock and green sock in my drawer. Without looking, I take one of the socks and shoot it a light year away. Then, I want to know what the color of the sock is. That information cannot travel to me quicker than 1 year, but all I have to do is look in my drawer and know that the sock a light year away is the other color. This way, I got information about something a light year away instantly.

u/i-deology

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ELI5: How does a ship pull back it’s anchor once it’s ready to go?

Engineering

All the videos on YouTube show how an anchor works, but none show how it’s pulled back once it’s deeply buried in the sea bed?

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