On Thu, May 14, 2015 at 01:04:09PM +1200, LizR wrote: > On 14 May 2015 at 12:32, Russell Standish <li...@hpcoders.com.au> wrote: > > > On Thu, May 14, 2015 at 11:26:17AM +1200, LizR wrote: > > > On 13 May 2015 at 18:20, Russell Standish <li...@hpcoders.com.au> wrote: > > > > > > > For a robust ontology, counterfactuals are physically instantiated, > > > > therefore the MGA is invalid. > > > > > > > > > > Can you elaborate on this? ISTM that counterfactuals aren't, and indeed > > > can't, be physically instantiated. (Isn't that what being counterfactual > > > means?!) > > > > No - counterfactual just means not in this universe. If its not in any > > universe, then its not just counterfactual, but actually illogical, or > > impossible, or something. > > > > > > > > As I mentioned, a simple example is my decision between tea and coffee. > > In > > > the MWI (or an infinite universe) there are separate branches (or > > > locations) in which I have both - but in the branch where I had tea, I > > > didn't have coffee, and vice versa. And because those branches can't > > > communicate, the road not taken remains counterfactual and non-physical > > > within each branch. Isn't that enough for the MGA to not need to worry > > > about counterfactuals, even in the MWI/Level whatever multiverse? > > > > > > > Why is communication needed? > > > > Because otherwise there can be no physical influence, and - within the > branch(es) in which the MGA is being carried out - the recorded system is > identical to the non-recorded one. Without any physical communication / > interference there is no difference from a single universe version. Well, > ISTM, at least. >
The "physical system" refers to all parallel instantiations of an object ISTM. If I refer to a photon travelling through a ZM apparatus (to fix things - you know two half silvered mirrors, so the photons are split and travel over two spatially disinct paths before being recombined), we don't have two different physical systems in play. Its just the one physical system, even though it occupies two distinct universes. How could it be otherwise? -- ---------------------------------------------------------------------------- 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 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.
