On Sun, Sep 28, 2014 at 1:39 AM, Russell Standish <li...@hpcoders.com.au> wrote:
> On Sat, Sep 27, 2014 at 03:43:56PM +0200, Platonist Guitar Cowboy wrote: > > On Sat, Sep 27, 2014 at 8:29 AM, Russell Standish <li...@hpcoders.com.au > > > > wrote: > > > > > On Sat, Sep 27, 2014 at 05:33:00AM +0200, Platonist Guitar Cowboy > wrote: > > > > On Sat, Sep 27, 2014 at 3:39 AM, Russell Standish < > li...@hpcoders.com.au > > > > > > > > wrote: > > > > > > > > So I don't see: robust universe => all integers exist > > > > > > Nor do I. But then that is the exact inverse of what I stated: the > > > arithmetic reality assumption in COMP entails a robust reality (one in > > > which the UD runs to completion). > > > > > > > If I remember the thesis correctly, than robust is a placeholder for some > > grandmother notion of physical reality, with enough consistency in > > historical/spatial/causal relations to allow the UD to run. Once reversal > > step is reached, the notion is dropped and isn't further needed. > > I think you're thinking of the term "concrete", which was somehow > synonymous with "primitive physical". > > This term was always problematic, as neither "concrete", "primitive" > nor "physical" were ever defined. I could not understand why the > integers, which were supposed to exist, could not satisfy "primitive > physicality". > I don't have Bruno's thesis here with me atm and with limited time/net access its hard for me to fish right now, but I don't think I'm stretching things with "robust" specifically. > > What is true, however, is that if the universe is robust, then the > reversal holds - whatever it is that is primitive, the only property > that is relevant to phenomenal physics is Turing completeness. > > This seques into the ontological problem that Jean de la Haye brings > up - and so does David Deutsch in his own way. If the primitive > universe were something like the Hilbert hotel, then we would expect > that the sorts of computations available in our empirical reality to > include hypercomputations - computations that go beyond the ability of > Turing machines. It is a fact that these hypercomputations are > conspicuously absent, so that raises the obvious question: why is the > primitive ontology restricted to just Turing complete systems? > Kind of old fashioned with this although I'll hear anybody out, but I still haven't seen anything that gives reason to break with sticking to Davis' position of "if we allow non-computable inputs then we can get non-computable outputs". But you're at the cutting edge of things about what happened since the 90s and not me, so... Say Schmidhuber is still limited by halting problem with his convergence time of output symbols. Aren't we and supernova, galaxy cluster already hyper enough as it is, as in 1:08 of this? https://www.youtube.com/watch?v=ba44JRAjpV4 Sorry, couldn't resist ;-) > > > > > > Therefore I can't see bi-conditional implication or material implication > > either way between the extravagant "for all practical purposes robust > > assumption" and properties of arithmetic in terms of ultrafinite, > > infinities etc. PGC > > > > When you say "for all practical purposes robust assumption" is > extravagant, are you arguing for ultrafinitism? This seems to contradict your name. If you are truly Platonist, your > reality is > robust. Relative to arithmetic perhaps but still not sure, in particular that non-robust implies or is implied by ultrafinite interpretation of arithmetic; to be clear, I'm don't buy ultrafinitism. I can see that when one asks for integral execution of UD one assumed some "concrete universe". But robust as property to address specialist skeptics of reversal at step 7 seems a placeholder more than something that is spelled out assuming comp, because the implied "consistent in historical/spatial/causal relations" doesn't need to be anymore precise as the thing is dropped. And for this indeed, especially the integral execution of UD, which is infinite we need infinite time and space. But I wouldn't jump to non-robust implying ultrafinite is perhaps a bit quick. Immaterial machines could be at work, everything is tucked into UD*, so I don't see why ultrafinite arithmetic would be needed. PGC -- 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/d/optout.
