[comp.unix.wizards] Turing machine simulation

tj@mks.UUCP (T. J. Thompson) (02/24/88)

In article <11893@brl-adm.ARPA>, dsill@nswc-oas.arpa (Dave Sill) writes:
> Turing machines are universal computational devices, but simulations
> of Turing Machines are not.

I would be curious to see a defence of this claim.
Consider, for example, a simulation of a Turing machine
run on a Turing machine.
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dsill@nswc-oas.arpa (Dave Sill) (02/26/88)

T. J. Thompson <tj@mks.uucp> writes:
>In article <11893@brl-adm.ARPA>, dsill@nswc-oas.arpa (Dave Sill) writes:
>> Turing machines are universal computational devices, but simulations
>> of Turing Machines are not.
>
>I would be curious to see a defence of this claim.
>Consider, for example, a simulation of a Turing machine
>run on a Turing machine.

Perhaps I should have said "Turing machines are universal
computational devices, but simulations of Turing machines are not
*necessarily* universal computational devices.

My point was that a vi-based TM simulation is not a universal
computer.

This is no longer a wizards issue.

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