clipka wrote:
> Darren New schrieb:
> 
>> Yes. Unbounded amounts of storage, not infinite amounts of storage. 
>> It's not difficult to arrange for a Turing machine to access however 
>> much memory it needs.
> 
> Consider a Turing machine that does not halt, but keeps advancing on the 
> tape.
> 
> There. Arrange for *that* to access however much memory it needs. It is 
> /not/ physically possible.

Yes. That doesn't make it infinite. You can arrange for that by making the 
speed of the machine 1/2^N where N is the number of slots filled in the tape.

You can't do that with something that needs an infinite amount of tape.

Sure, I was unclear. You can't arrange for *every* machine to have as much 
tape as it needs. But you *can* arrange for *some* machines to have as much 
tape as they need, which is *not* the case for a programming paradigm that 
requires an infinite amount of storage. Most of the practically interesting 
machines do *not* consume unlimited amounts of memory before they halt.

-- 
   Darren New, San Diego CA, USA (PST)
   I ordered stamps from Zazzle that read "Place Stamp Here".

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