On May 29, 5:04 am, apoorv <skj...@gmail.com> wrote: > On May 28, 6:29 pm, apoorv <skj...@gmail.com> 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: > > > > > On Sun, 26 May 2013, apoorv wrote: > > > > > On May 27, 8:13 am, William Elliot <ma...@panix.com> wrote: > > > > > > On Sat, 25 May 2013, apoorv 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. > > > > > > The external input and the output have to be combined > > > > > So the second TM is necessary? > > > > > Input 1 on the right side, gives output 1 on the left side. > > > > When done, imput 1 is erased and output 1 copied to the right side > > > > where it's now imput 2. Imput 2 is used by the same machine > > > > to produce output 2 on the left side. > > > > Starting left and finishing right is just a convention. > > > > n=1 > > > TMn - Start left, finish left, signal halt. > > > n++ > > > repeat > > > > Seems there is never an output. > > > > Herc > > > --www.phpPROLOG.com > > > 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 > > An interesting thought. Since the brain uses > Almost real time feedback ,if at all it is digital > nature, then we should look for not one but two > Processors. Processor 1 receives the external input > And the output from processor 2 ,(this is also the > Final output). The combined input then goes to processor > 2, which generates the final output. > A flow diagram -: > > External input-------->Processor 1-->- > (sensory). | | > /\. |Total input > Fin output internal feedback| > |minimal lag | > Final output<----------Processor2--<-- > (motor ) > > -Apoorv
Anything this does can be Emulated by 1 TM.
This is all modelled much more accurately using L-->R reduction grammars with terminal and non-terminal (final output) symbols.
SEE EBNF Grammar.
I have an example of USER INPUT parsing with EBNF that defines the PROLOG SYNTAX at