From: Bill Hibbard (test@demedici.ssec.wisc.edu)
Date: Fri Oct 15 2004 - 15:23:49 MDT
Hi John,
The difference is that a Turing machine can add arbitrary
integers and finite state machines (and you) cannot. For
any halting computation a Turing machine uses a finite amount
of tape, but it will always have as much as it needs. There
is no integer too big for it to handle, as there is for
finite state machines.
Cheers,
Bill
On Thu, 14 Oct 2004, fudley wrote:
> Some have said a Turing machine is not realistic because it invokes
> infinity, such as an infinitely long tape (memory), but this is not
> true; it only needs a finite but indeterminate length of tape. Any
> physical Turing machine would be running at a finite speed and so would
> only need infinite tape if it were running for an infinite amount of
> time. If I say I can prove this particular Turing machine will never
> stop what I mean is that for any finite amount of time you give me I can
> show you that if it still has enough (finite) tape then it is still
> running.
>
> John K Clark
This archive was generated by hypermail 2.1.5 : Tue Feb 21 2006 - 04:22:47 MST