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Comment by nightcracker | Hacker News Reader

And how is everyone supposed to know when to leave their room and where to go?

They all hear an announcement at the same time via the hotel’s speaker system. (And we’re already ignoring so many laws of physics that the speed of light is the least of our problems.)

In a universe with an infinite speed of light, can there even be any kind of waves? Do physical waves not also propagate instantly?

What kind of waves? I guess you could at least have a light source that periodically gets brighter and dimmer and a detector at the other end of the universe would detect the brightness oscillation and it would not really make any difference whether the light propagates with an finite or infinite speed besides of course the propagation time.

> What kind of waves?

Any wave! Including sound waves.

> I guess you could at least have a light source that periodically gets brighter and dimmer

Would it even be possible to make a timer that periodically gets brighter and dimmer in a world with an infinite speed of light? Would the crystal oscillators in CPUs still work?

I believe that some processes (like nuclear decay) stop happening when there's an infinite speed of light. I guess my overall question is: does time still exist in a world with an infinite speed of light?

Can you explain how all of that would follow? Naively, if we take the limit of c to infinity, aren’t we simply back to Newtonian physics? Why wouldn’t a pendulum work, for example?

The laws of physics get chucked out the window the moment you say "infinitely many rooms".

There is a screen in each room that shows you a message when to move where. Or you get a call from the receptionist, but not an individual call but one broadcasted to all rooms, announcing the formula for your new room number. Make up whatever you want, its a thought experiment.

It's a very unique universe that quite a bit different that ours - It would require an infinite amount of energy to communicate that call leading to infinite entropy. Given that the moves happen instantaneously, the first guest to arrive would instantly cause the heat-death of this universe.

They always leave their room after 24hrs and go to the room next door?

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