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Topic: Feedback in Turing Machines
Replies: 17   Last Post: May 29, 2013 12:36 AM

 Messages: [ Previous | Next ]
 apoorv Posts: 53 Registered: 4/11/13
Re: Feedback in Turing Machines
Posted: May 28, 2013 11:14 PM

On May 29, 6:38 am, William Elliot <ma...@panix.com> wrote:
> On Tue, 28 May 2013, apoorv wrote:
> > On May 27, 10:37 am, Graham Cooper <grahamcoop...@gmail.com> wrote:
> > > On May 27, 2:32 pm, William Elliot <ma...@panix.com> wrote:
> > > > > > > Is there some study on situation where the output from a TM at time T is
> > > > > > > fed back so that the total input at time T+1 is some function of output
> > > > > > > at time T and external input at time T+1.?

>
> > > > > > So imput is on the right and out on the left and when done at time
> > > > > > t, move the output to the right of the tape and start again.

>
> > > > > > Time t+1 begins the new output from the old output. You get to wait
> > > > > > until time t2 for the full second output.

>
> > Eliot's post ,which appears to be deleted, showed that a single TM , could
> > implement feedback. However, if we put the added Requirement that the input
> > at time t is processed with delay not exceeding A fixed time t0, then two TM
> > s appear necessary . -Apoorv

>
> If t0 - t is larger than processing time, then you wouldn't.
>
> However for a second machine to start at time t+1 or some
> time t0 when t0 - t is less than processing time, a second
> machine can't wait until the output is completed, it has
> to be processing the output as is it' coming out.

The machine receives external input EI(t).It must combine this with
the Feedback of Output EO(t-to) to create total input TI(t).This is
then the Total input TI(t) for the machine.Thus the Total Input
corresponding to time t is being processed at some time t+ d. If we
Fix d to be some acceptable time interval, then a single processor May
not suffice.
Second, I found that the formatting of the flow chart got disturbed.
Just to repeat it with minimal formatting:
Ext Input -->-----processor 1-->--Total Input->--proc 2-->---Output
|------<internal feedback minimal lag---<--|
The processing with internal feedback represents internal processes
Of the brain. The feedback loop can be active with no Ext Input or
Visible output ( Like thinking?).A break between processor 1 and 2
Will stop processing, between ext input and processor 1 loss of
sensory ability; between processor 2 and output , loss of motor
ability; and of the feedback loop , loss of thinking?

-apoorv

Date Subject Author
5/25/13 apoorv
5/25/13 apoorv
5/26/13 Graham Cooper
5/26/13 Graham Cooper
5/26/13 apoorv
5/26/13 Graham Cooper
5/27/13 apoorv
5/26/13 William Elliot
5/27/13 apoorv
5/27/13 William Elliot
5/27/13 Graham Cooper
5/27/13 David Bernier
5/28/13 apoorv
5/28/13 apoorv
5/28/13 Graham Cooper
5/28/13 William Elliot
5/28/13 apoorv
5/29/13 Graham Cooper