Please bring this century old debate to completion? Can someone give a short status update on what different people think? Please, I am interested but cannot read all of it. 10-15 years ago I was really into this and then I dropped out. Seems like an endless debate.
David David Jonsson, Sweden, phone callto:+46703000370 On Fri, Sep 11, 2009 at 6:51 PM, Stephen A. Lawrence <sa...@pobox.com>wrote: > > > Mauro Lacy wrote: > >> Mauro Lacy wrote: > >> > >> > >>> By the way, I have a question for you, in the form of a zen koan: "We > >>> > > know the sound of two hands clapping, but what is the sound of one hand > > clapping?" We can reformulate it for the ocassion as: "We know the > > interference pattern produced by two streams of light, but what is the > > interference pattern of one stream of light?" > > > >> A diffraction pattern. > >> > > > > A diffraction pattern in a medium, and depending on that medium. That is, > > the effect is the result of an interaction. > > > > I don't know what you mean by this. No "medium" is required. A single > beam of light traveling through vacuum diffracts with itself (or > interferes with itself, if you prefer; it's really the same effect). > That's why lasers can never be perfectly collimated; the beam always > spreads. > > Or have you discarded the usual meaning of the word "medium" in favor of > something else? > > > > >> > >>> Or better yet: > >>> "We know the gravitational effect between two material bodies, but what > >>> > > is the gravitational effect of one material body?" > > > >> Curves the metric. > >> > >> But without any other body in the universe there's nobody there to > >> > > measure it. > > > > So, an effect again arises as a result of an interaction. > > > > > >> If a tree falls in a forest and there's nobody there to hear it, does it > >> > > make a sound? > > > >> Same question wearing different clothes. In both cases it's just > >> > > semantic games with an undefined term. In the question regarding the > > tree, the phrase "make a sound" was never defined and so the issue > > appears debatable. In your example, the word "effect" was never > > defined, and so the question appears debatable. > > > > The question is debatable. Although only semantically, if you like. If > you > > define sound as "something audible" then it only occurs when someone > hears > > it, by definition. But if you define "sound" as something that has the > > possibility of being audible, then there's sound even when nobody hears > > it, again by definition. And this is the right way to define it, IMO, > > because if not, you're left in the dark regarding the real nature of > > things. The specific phenomena of sound manifests when somebody hears it, > > but while nobody is hearing it, there's something there that, when > someone > > heards it, manifests itself as sound. > > > > But I was pointing to another direction: trying to show that the specific > > form of things we perceive or phenomena that occurs in the world, are the > > result of an interaction. > > > > Obviously. That's the heart of the Copenhagen interpretation of quantum > mechanics: The observer is part of the system, and the act of observing > is an interaction. Without the presence of the observer, it's a > different system. > > > In the same venue, gravity only makes sense as a result of the > interaction > > of two or more massive bodies. > > What does it mean for something to "make sense"? Without a precise > definition of that phrase the sentence is meaningless. > > For that matter, you haven't said what *you* mean by "interaction" or > "massive" or "body". Is a photon "massive"? Is a neutron star one > body, or is it a whole bunch of bodies, one for each neutron? Does a > ray of light which is bent by a massive star constitute an "interaction" > of that star with another "massive body", or not? > > Everything is debatable when nothing is defined. > > > > In a sense, gravity phenomenologically IS > > the result of that interaction, that is, gravity is different when > there's > > an interaction, > > This sounds kind of meaningless, frankly. "Different" how? What do you > mean by an "interaction"? > > More fun with undefined terms. > > > to when there's none, and that difference depends also on > > the interacting bodies, in the same way as a diffraction pattern depends > > on the medium, > > No it doesn't, as I already pointed out. > >
