Re: On the nature and existence of many non computational things

2014-01-17 Thread Bruno Marchal

Dear Stephen,

On 16 Jan 2014, at 15:11, Stephen Paul King wrote:


Dear Bruno,

  I would like to start a new thread to discuss the nature and  
existence of the many non computational things that you have  
mentioned in your posts.


See my explanation of the phi_i to Liz. (on FOAR, I think). It is a  
direct consequence of the existence of a universal machine.
I usually prove, in one (double) diagonalization that the predicate  
TOTAL for the machine is not computable.

In fact most predicate *on* machine are not computable.




   Could you find a few moments to write some remarks on these?


I can come back on this. perhaps when they are less posts! I intend to  
explain first a bit of modal logic, but of course that computability  
issue is important. But this is something I have already explained  
more than once. Modal logic have only be explained one time, and a  
very long time ago. I think that this is a bit more urgent. But don't  
worry, we will spiral on computability again.




In particular I wonder if their proposed non-computability can be  
expanded into disjoint classes such that we have some kind of  
taxonomy of properties.


Well, yes. the degree of non computability is an entire branch of  
mathematical logic.





Can they be represented approximately by a finite language?


You can axiomatize them in second order logic, or analysis.



   Other than the restriction of recursive enumerability (modulo  
homeomorphisms of their topological duals), what is it, in your  
opinion, that makes such things non-computable?


Universality. That's a theorem. Its proof is very short (but needs  
revision in elementary math). We will come back on it. I do explain  
this in most of my papers (but perhaps too much concisely). Don't  
hesitate to recall me on this if necessary.


Best,

Bruno







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Stephen Paul King

Senior Researcher

Mobile: (864) 567-3099
stephe...@provensecure.com

 http://www.provensecure.us/




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On the nature and existence of many non computational things

2014-01-16 Thread Stephen Paul King
Dear Bruno,

  I would like to start a new thread to discuss the nature and existence of
the many non computational things that you have mentioned in your posts.
   Could you find a few moments to write some remarks on these? In
particular I wonder if their proposed non-computability can be expanded
into disjoint classes such that we have some kind of taxonomy of
properties. Can they be represented approximately by a finite language?
   Other than the restriction of recursive enumerability (modulo
homeomorphisms of their topological duals), what is it, in your opinion,
that makes such things non-computable?

-- 

Kindest Regards,

Stephen Paul King

Senior Researcher

Mobile: (864) 567-3099

stephe...@provensecure.com

 http://www.provensecure.us/


“This message (including any attachments) is intended only for the use of
the individual or entity to which it is addressed, and may contain
information that is non-public, proprietary, privileged, confidential and
exempt from disclosure under applicable law or may be constituted as
attorney work product. If you are not the intended recipient, you are
hereby notified that any use, dissemination, distribution, or copying of
this communication is strictly prohibited. If you have received this
message in error, notify sender immediately and delete this message
immediately.”

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