From: Virgil on
In article <slrni2dgpo.jrj.tim(a)soprano.little-possums.net>,
Tim Little <tim(a)little-possums.net> wrote:

> On 2010-06-26, Charlie-Boo <shymathguy(a)gmail.com> wrote:
> > It is trivial to calculate in binary (using only 0 and 1) and output
> > any desired string surrounded by 2 whenever we want
>
> You use the singular here, by which your statement is correct. Any
> single finite string can be so produced. What's more, any finite
> sequence of finite strings can be produced.
>
> However, you need an infinite sequence of finite strings to define
> most real numbers, and there are not enough finite algorithms to
> produce them all.

It is well known that for 'most' reals no such algorithm can exist, the
non-computable transcendentals.
From: Newberry on
On Jun 26, 8:19 pm, Tim Little <t...(a)little-possums.net> wrote:
> On 2010-06-26, Charlie-Boo <shymath...(a)gmail.com> wrote:
>
> > It is trivial to calculate in binary (using only 0 and 1) and output
> > any desired string surrounded by 2 whenever we want
>
> You use the singular here, by which your statement is correct.  Any
> single finite string can be so produced.  What's more, any finite
> sequence of finite strings can be produced.
>
> However, you need an infinite sequence of finite strings to define
> most real numbers, and there are not enough finite algorithms to
> produce them all.
>
> - Tim

If I understand Charlie's definition correctly some of the machines
will keep outputing digits forever. That is what I meant when when i
said that pi and e are generated by an algorithm. There are enough
algorithms to produce all the compressible infinite strings.
From: Newberry on
On Jun 26, 8:12 pm, Tim Little <t...(a)little-possums.net> wrote:
> On 2010-06-26, Newberry <newberr...(a)gmail.com> wrote:
>
> > If the Turing machine is hacked such that it outputs a digit on any
> > state transition does it not represent a real?
>
> Suppose I have a Turing machine that repeatedly marks and erases a
> symbol at the start position. What real are you saying that this
> machine represents?
>
> - Tim

Well, the Turing machine includes a state machine. On each state
transition it outputs a digit. Let us say that the machine outputs 1
on every state transition. The it represents the number
0.111111111111111111111111....1111111...........
From: Newberry on
On Jun 26, 8:13 pm, Virgil <Vir...(a)home.esc> wrote:
> In article
> <382a8f19-157c-4c0a-9ed2-b9c295ce0...(a)5g2000yqz.googlegroups.com>,
>
>
>
>
>
>  WM <mueck...(a)rz.fh-augsburg.de> wrote:
> > On 26 Jun., 23:14, "Mike Terry"
> > <news.dead.person.sto...(a)darjeeling.plus.com> wrote:
> > > "WM" <mueck...(a)rz.fh-augsburg.de> wrote in message
>
> > >news:511dd6ef-6fe7-4664-bda0-082971c2f8db(a)z10g2000yqb.googlegroups.com....
>
> > > > On 26 Jun., 00:32, "Mike Terry"
>
> > > > > > Please let me know: Does the list consisting of A0, A1, A2, A3, ...
> > > > > > contain its antidiagonal or not?
>
> > > > > No, of course not.
>
> > > > The set of all these antidiagonals A0, A1, A2, A3, ... constructed
> > > > according to my construction process and including the absent one is a
> > > > countable set.
>
> > > Yes, I've agreed that several times.
>
> > > > > > That is not a problem. It shows however, that there are countable sets
> > > > > > that cannot be listed.
>
> > > > > How exactly does it show that there are countable sets that cannot be
> > > > > listed?
>
> > > > See the one above: The results of my construction process.
>
> > > No. The above shows that you've constructed a countable sequence of numbers
> > > (A0, A1, A2, A3,...) which CAN be listed, namely consider the list (A0, A1,
> > > A2, A3,...).
>
> > > Read carefully!
>
> > In order to do so, I posed the question: Does the list consisting of
> > A0, A1, A2, A3, ... contain its antidiagonal or not?
>
> No list contains its antidiagonal, nevertheless, any list together with
> its antidiagonal can be listed, and  in a large variety of ways.
>
>
>
> > You said no. Therefore your assertion "which CAN be listed" is plainly
> > wrong.
>
> Nonsense.
>
>
>
> > Of course it is not possible to list a list and its antidiagonal.
>
> Whyever not?
>
> Given a list {b0, b1, b2, ...} and its antidiagonal, a, how is the llist
> {a, b0,. b12, b2, ...} NOT a list of the original list plus its
> antidiagonal?
>
>
>
> > > > > OK, but you've still not given any explanation why you think the
> > > > > antidiagonals of your process cannot be listed! (I'm genuinely
> > > baffled.)
>
> > > > You said so yourself, few lines above.
>
> > > Rubbish. I have never said anything other than that (A0, A1, A2, ...) is a
> > > countable sequence of reals that CAN be listed
>
> > but not with all its antidiagonals.
>
> Since any such list has potentially uncountably many "antidiagonals", of
> course not.
>
> But any list along with up to countably many of its antidiagonals can be
> collectively listed.
>
>
>
> > > Go on - have one more go, then I'll give up...
>
> > You'd better give up than make contradictory claims.
>
> Good advice. Its a shame its author doesn't follow it himself.- Hide quoted text -
>
> - Show quoted text -

If we create a list of ALL the antidiagonals, how come there EXISTS an
antidiagonal not on he list.

I wonder if you can perform this construction in ZFC.
From: Charlie-Boo on
On Jun 26, 3:40 pm, Virgil <Vir...(a)home.esc> wrote:
> In article
> <1a5a0da4-01d1-41c5-b64b-dcc53e5ce...(a)k39g2000yqb.googlegroups.com>,
>
>
>
>
>
>  Charlie-Boo <shymath...(a)gmail.com> wrote:
> > On Jun 25, 3:25 pm, Virgil <Vir...(a)home.esc> wrote:
> > > In article
> > > <adaa005c-c180-4ce0-8d2c-81da912c6...(a)w12g2000yqj.googlegroups.com>,
>
> > >  Charlie-Boo <shymath...(a)gmail.com> wrote:
> > > > On Jun 24, 8:49 am, Aatu Koskensilta <aatu.koskensi...(a)uta.fi> wrote:
> > > > > Charlie-Boo <shymath...(a)gmail.com> writes:
> > > > > > On Jun 15, 2:15 am, "Peter Webb"
>
> > > > > >> No. You cannot form a list of all computable Reals.
>
> > > > > > Of course you can - it's just the list of Turing Machines.
>
> > > > > No, it's not.
>
> > > > I asked for a counterexample, to no avail.  Don't you think you should
> > > > substantiate your statement or retract it?
>
> > > > Each Turing Machine represents some computable real (all computable
> > > > reals are included) and you can list those Turing Machines.  The
> > > > Turing Machine represents it as well as any other system of
> > > > representation.
>
> > > Aren't there Turing machines that don't represent any real at all?
>
> > No.  In general terms, every TM computes some result from its input.
> > Agree?  Then if we start with an empty tape, it represents a
> > constant.  How we map its execution history determines which real
> > number that represents.  There is generally a way to indicate which
> > actions constitute output, which is needed when we use an infinite
> > representation such as its real number binary expansion.
>
> > If the executon history can be finite, we can map all finite strings
> > into real numbers, as well as the infinite ones as described above.
>

> How does one associate TMs which are nonterminating but cyclic and
whose
> cycle depends on the input tape?- Hide quoted text -

It's a function with a rational value e.g. it calculates 1/x and when
x=3 the cycles is (3). But that has nothing to do with (doesn't exist
in) a system for representing constants.

C-B

>
> - Show quoted text -