On 25 Jul 2013, at 23:01, Joseph Knight wrote:

So is physics best understood as a computer program with access to a random oracle? (Coming from 1-indeterminacy.)

That is possible but should remain to be proved. A priori, physics emerges from all computations, and the mixing of computability and non computability might be non equivalent with computable + a random oracle. I suspect it not, both empirically and theoretically with computationalism.

Bruno

PS I will have to put my computer in a box, as I am moving, so I will be disconnected for awhile. Thanks for being patient for a possible answer to your next possible comment.




On Mar 31, 2013 8:13 AM, "Bruno Marchal" <marc...@ulb.ac.be> wrote:

On 31 Mar 2013, at 01:15, Joseph Knight wrote:

Sorry for the vagueness of my question; I would not count pi as a physical constant. I would count the empirically determined circumference:diameter ratio for a circle in our observed curved spacetime as a physical constant.

The reason I asked is because Bruno has repeatedly claimed that COMP=>"noncomputability of physics" but I'm wondering what exactly this would mean in practice.


In practice it would mean that some phenomena are not predictible or computable. Russell and Brent are right, it comes from the FPI (first person indeterminacy) which introduces "genuine randomness" in the first person experience. In fact that randomness might be so great as leading to the "white rabbits", and with comp it is astonishing that the world around us seems so much computable. But the redundancy of the UD, and the constraints of correct self-reference add much structure, and if comp is true, that should be enough. The non computable sequence will still have computable distribution, like with QM, when, for example, we send a sheaf of electron is the 1/sqrt(2)(up + down) on a up/down Stern-Gerlach analyser. From the first person perspective, this leads to uncomputable sequence of events (even incompressible strings of up and down), but statistically, with Avogadro-like numbers of particles, the electronic sheaf will just split in symmetrical halves, like the big number statistical laws predict.

It is an open problem if there are non computable constants in nature, as it is an open problem if some oracle might play a role in the development of the appearance of physical laws in the UD (or in arithmetic). That seems unlikely, but who knows? As Brent says, that would be hard to test, but it might make some sense from theoretical assumption, both in comp-physics, and in theoretical physics. Note that it is easy to build a non computable solution to the SWE (something like Ae^ikHt, with k a non computable number, but it is impossible to test the non computability of such wave in case they occur. Machines can prove only the individual incompressibility of a *finite* number of strings.

Bruno



On Mar 30, 2013 6:53 PM, "Russell Standish" <li...@hpcoders.com.au> wrote:
On Sat, Mar 30, 2013 at 04:15:54PM -0700, Joseph Knight wrote:
> True or False: COMP implies that any fundamental physical constant is non
> computable?
>

I would say false, unless you can say that pi is _not_ a physical
constant. Another example that springs to mind is the magnetic moment
of the neutron which is definitely physical, but maybe not fundamental.

--

----------------------------------------------------------------------------
Prof Russell Standish                  Phone 0425 253119 (mobile)
Principal, High Performance Coders
Visiting Professor of Mathematics      hpco...@hpcoders.com.au
University of New South Wales          http://www.hpcoders.com.au
----------------------------------------------------------------------------

--
You received this message because you are subscribed to a topic in the Google Groups "Everything List" group. To unsubscribe from this topic, visit https://groups.google.com/d/topic/everything-list/53ZNGv7qPpo/unsubscribe?hl=en . To unsubscribe from this group and all its topics, send an email to everything-list+unsubscr...@googlegroups.com . To post to this group, send email to everything- l...@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list?hl=en .
For more options, visit https://groups.google.com/groups/opt_out.



--
You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything- l...@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list?hl=en .
For more options, visit https://groups.google.com/groups/opt_out.



http://iridia.ulb.ac.be/~marchal/




--
You received this message because you are subscribed to a topic in the Google Groups "Everything List" group. To unsubscribe from this topic, visit https://groups.google.com/d/topic/everything-list/53ZNGv7qPpo/unsubscribe?hl=en . To unsubscribe from this group and all its topics, send an email to everything-list+unsubscr...@googlegroups.com .
To post to this group, send email to everything-list@googlegroups.com.
Visit this group at http://groups.google.com/group/everything-list?hl=en .
For more options, visit https://groups.google.com/groups/opt_out.



--
You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com.
To post to this group, send email to everything-list@googlegroups.com.
Visit this group at http://groups.google.com/group/everything-list.
For more options, visit https://groups.google.com/groups/opt_out.



http://iridia.ulb.ac.be/~marchal/



--
You received this message because you are subscribed to the Google Groups 
"Everything List" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to everything-list+unsubscr...@googlegroups.com.
To post to this group, send email to everything-list@googlegroups.com.
Visit this group at http://groups.google.com/group/everything-list.
For more options, visit https://groups.google.com/groups/opt_out.


Reply via email to