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Does a turing machine have the concept of 'time'?

I've studied the basic turing machine theory as an undergraduate. I never saw any mention of a timed turing maching. An example: a turing machine that counts the number of seconds passed since it started.

Modern computers clearly have the capacity to do this. So, a computer's capability is a superset of what a turing machine can do. Are there some articles/math/documentation on this? Or is my argument wrong at some point?

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Utkarsh Sinha Avatar asked Jun 22 '12 22:06

Utkarsh Sinha


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1 Answers

Turing machine doesnt use time because it doesnt need to, it's a purely computational device, and computation is not derivation of time, but the time is derivation of computation. Still, it's a mechanical device, so because of that it takes time to make steps, so the machine can potentially count this time too, but that would require another truing machine to do it.

ps. It's because of the entropy, the time is derived from computation. You can reset computer in no-time, - this is in the opposite direction of entropy. So that's why booting almost always takes longer than shutting down, especially if you disconnect the power.

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Andrew Avatar answered Oct 06 '22 04:10

Andrew