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Ask HN: Assume the universe is a simulation. Why is c the speed of light?

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Re: Ask HN: Assume the universe is a simulation. Why is c the speed of light?

#21

Post by vinaybn »

networked wrote: post #3

A connection between the simulated universe's speed of light and its host CPU's clock speed would imply real-time simulation. I see no reason why that would necessarily be the case for a simulated universe; most research-grade physics simulations humans run today aren't real-time. (They would be real-time or faster if we had the hardware to run them that way — I imagine a sufficiently accurate physics "REPL" would he…

This doesn't make sense to me. Assuming this is a simulation, real-time isn't "real" time.

Re: Ask HN: Assume the universe is a simulation. Why is c the speed of light?

#22

Post by [deleted] »

networked wrote: post #3

A connection between the simulated universe's speed of light and its host CPU's clock speed would imply real-time simulation. I see no reason why that would necessarily be the case for a simulated universe; most research-grade physics simulations humans run today aren't real-time. (They would be real-time or faster if we had the hardware to run them that way — I imagine a sufficiently accurate physics "REPL" would he…

[deleted]

Re: Ask HN: Assume the universe is a simulation. Why is c the speed of light?

#26

Post by networked »

vinaybn wrote: post #21
networked wrote: post #3

A connection between the simulated universe's speed of light and its host CPU's clock speed would imply real-time simulation. I see no reason why that would necessarily be the case for a simulated universe; most research-grade physics simulations humans run today aren't real-time. (They would be real-time or faster if we had the hardware to run them that way — I imagine a sufficiently accurate physics "REPL" would he…

This doesn't make sense to me. Assuming this is a simulation, real-time isn't "real" time.

By "real-time" above I mean from the perspective of whoever runs the simulation. Compare: https://en.wikipedia.org/wiki/Real-time_simulation.

Re: Ask HN: Assume the universe is a simulation. Why is c the speed of light?

#27

Post by iyn »

brudgers wrote: post #14

The puzzlement consists of using "universe" in two incompatible contexts without paying clear attention to the distinction between the contexts. The first context is the ordinary one in which the universe is roughly the container for everything that is including ourselves. The other context is one in which the universe is a simulation of a container for everything that is including ourselves that is indistinguishable…

I have a similar view, but at the same time I still have a little bit of hope that even if the universe was a simulation, there would be some way to somehow go outside the simulation (e.g: by 'thinking', if that would make sense, about outside-the-simulation concepts; something like escaping the VM). But it's kind of an emotional reaction to the realization of the limits of one's mind/perception ;).

Re: Ask HN: Assume the universe is a simulation. Why is c the speed of light?

#28

Post by inlineint »

Actually the speed of light is just a constant that interconnects spatial and time coordinates.

In special relativity everything moves with c light speed in a 4-dimentional pseudo-Euclidian space. It means that the light speed constant c is just a measure unit that interconnects time and spatial coordinates. And the actual spatial velocity of a particle is just a projection on the spatial coordinates of it's 4-dimentional velocity which always has length equal to c.

So the existence of light speed constant seems more like a boundary condition that limits class of possible solutions rather than something connected with the processor's clock-speed.

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