Re: [PO] Re: Can a regular Turing Machine provide Protected Memory?

From: Simon G Best (s.g.best_at_btopenworld.com)
Date: 08/28/04 

Date: Sat, 28 Aug 2004 16:26:55 +0000 (UTC)

Peter Olcott wrote:
> "Simon G Best" <s.g.best@btopenworld.com> wrote in message news:413072ED.6040504@btopenworld.com...
>
>>A state transition table describes the behaviour of a TM. The TM itself
>>doesn't necessarily contain a copy of that table, but how a TM works
>>internally is unimportant, anyway.
>
> Its not psychic, therefore it contains the table.

No. It could contain gear wheels, levers, and so on, and no table at all.

>>Hardware isn't software.
>
> Tell that to the BIOS ROM. (Software as hardware)

Oh, you want to play games with semantics when you're so hopelessly
inept when it comes to actually writing what you mean?

> The mistakes have mostly not been mine, but, the habit
> of others of leaping to conclusions.

Such arrogance!

You obviously need some more punishment, so:

String B: "String B will never be proven to constitute a true, valid
statement."

String C: "String B will never be proven to constitute a true, valid
statement."

String B will never be proven to constitute a true, valid statement.

What about string C?

>>By the way, it's a /really/ good idea to read /all/ the way through a
>>post /before/ even beginning to reply. You obviously haven't done this.
>
> This is inefficient.

You need to learn what 'less haste, more speed' means.

>>In section 1 of his 1936 paper 'On computable numbers, with an
>>application to the Entscheidungsproblem', Turing says:-
>>
>>"The machine is supplied with a "tape" (the analogue of paper)..."
>
> <sarcasm>

I'm British; sarcasm should not be marked up.

> And of course everyone universally agrees that the term analogue
> means one-and-the-same-as.
> </sarcasm>

But if you'd read just a bit further first, you would have read:

>>Why an "analogue"? Because, when it comes down to it, Turing Machines
>>are /mathematical/, /not/ physical. The seemingly physical things, such
>>as a "tape", and so on, are really for illustrative purposes.

Yes, I see now: not bothering to first read the post you're replying to
is certainly a more efficient way of embarassing yourself.

> Yet to continue with the illustration there often comes a point
> where simplifying assumptions must be modifyed.

You also need to read back what you wrote /before/ posting it.

> Punched paper tape might be reliable.

So what? We're talking about Turing Machines. Turing Machines are
mathematical.

> I am so old that I
> was able to have one of my homework assignments
> written to punched paper tape.

You are not the first net.kook to surprise me with your age. You come
across as so much less mature.

> Pencil written and
> erased paper tape (your suggestion) is absurd.

No, it's not my suggestion. If it's anyone's, it's Turing's. But it's
just illustrative; Turing Machines are actually mathematical.

> It is
> a simplifying assumption that does not hold up in any
> real-world scenarios.

Turing Machines are mathematical.

> Since you already agreed that
> magnetic tape is acceptable, let's go with that.

No, there are technical problems with infinitely long magnetic tapes.

Anyway, Turing Machines are mathematical. (Perhaps, if I say this
enough, you'll actually read it at some point.)

> Now how
> does a human get anything onto this tape, or review
> the tapes contents?

An off-line tape reader/writer, as I said in my previous post.

It really would be a lot more efficient for you to actually read all the
way through the posts you reply to, then you wouldn't waste time raising
irrelevant points that have already been dealt with.

> I would say that something like
> a keyboard and CRT are logically entailed.

If you like. But Turing Machines are mathematical.

> Now we are back to my original method that uses
> (1) Read Only Memory
> (2) Protected Memory
> (3) Write Only Memory
> It provides the result of its halt analysis only on the CRT
> screen, no LOOP_IF_HALTS TM can be constructed.

So, you've given up with Turing Machines, and decided to return to ideas
that have been thoroughly and repeatedly debunked many times before?
Obviously you've realised that you can't defeat the Halting Problem, and
so have decided to resort - yet again - to various obfuscations to try
to disguise your failure. It isn't working.

The classic proof is about Turing Machines. Your extra hardware is
irrelevant, and shall be ignored (except for the purposes of fun).

Simon

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