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

Sorry for the vagueness of my question; I would not count pi as aphysical constant. I would count the empirically determinedcircumference:diameter ratio for a circle in our observed curvedspacetime as a physical constant.The reason I asked is because Bruno has repeatedly claimed thatCOMP=>"noncomputability of physics" but I'm wondering what exactlythis 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 constantis 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 momentof the neutron which is definitely physical, but maybe notfundamental.-- ---------------------------------------------------------------------------- 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 inthe 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 GoogleGroups "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?hl=en.For more options, visit https://groups.google.com/groups/opt_out.

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