On 01 Aug 2011, at 01:12, Craig Weinberg wrote:
What machine attributes are not Turing emulable? I thought Church says
that all real computations are Turing emulable.
But for Church the "real computations" are what can do a finite mind
with a finite set of transparent instructions, in a finite time, but
with as much memory and time he needs. It is the "intuitively
computable functions". There is no reference at all with any idea of
"real" in the sense of physically real, which is something never
defined. David Deutsch has introduced a "physical" version of Church
thesis, but this has no bearing at all with Church thesis. Actually I
do think that Church thesis makes Deutsch thesis false, but I am not
sure (yet I am sure that Church thesis + "yes doctor" leads to the
existence of random oracle and local violation of Church thesis by
some physical phenomena (akin to iterated self-multiplication).
You received this message because you are subscribed to the Google Groups
"Everything List" group.
To post to this group, send email to email@example.com.
To unsubscribe from this group, send email to
For more options, visit this group at