On Thursday, April 3, 2014 7:56:55 AM UTC+1, Liz R wrote: > > On 3 April 2014 16:56, <ghi...@gmail.com <javascript:>> wrote: > >> >> On Thursday, April 3, 2014 3:07:26 AM UTC+1, Liz R wrote: >> >>> On 3 April 2014 14:39, <ghi...@gmail.com> wrote: >>> >>>> >>>> On Thursday, April 3, 2014 1:24:28 AM UTC+1, Liz R wrote: >>>>> >>>>> gbhibbsa, I'm getting a bit confused here. All I said is that >>>>> wavefunction collapse isn't an observed fact, which seems to me a fairly >>>>> reasonable statement, because we can't observe entities like >>>>> wavefunctions >>>>> directly, and we certainly can't observe their collapse directly. Some >>>>> people would say we can't observe *anything* directly, but under the >>>>> normally understood meaning of "observe" it seems reasonable to say that >>>>> we >>>>> observe the images on our retinas, and hence that we can observe the dots >>>>> on a screen, and we can also be reasonably said to be able to observe the >>>>> pattern they make. I'm not saying anything about the MWI or Copenhagen or >>>>> whatever here, merely that (in normal usage of "observe") we can observe >>>>> dots on a screen, and we can't observe abstract theoretical entities like >>>>> wavefunctions, or their collapse. >>>>> >>>> >>>> I apologize for the extensive subset of my much more extensive range of >>>> shortcomings causing up to all of that confusion. >>>> >>>> May I try again...this time boiling it all down to a single >>>> request? Based on what was at the time the widely accepted proxy for >>>> the more problematic meaning of 'observation', what was observed that gave >>>> rise in the first place to the widely perceived, arguably urgent, need for >>>> an Interpretation of what it meant? >>>> >>> >>> The observation described above, and shown in the pictures. The need for >>> interpretation comes from the fact that the objects (electrons or photons, >>> for example) involved are assumed to be far too small to be influenced by >>> both slits in the experiment (the fact that they form localised dots on the >>> screen also indicates that they are very small). Yet all these small >>> objects manage to build up a global interference pattern involving the >>> presence of both slits (a pattern that vanishes if one slit is covered). >>> >>> This doesn't at first seem paradoxical, because a similar phenomenon >>> occurs when a wave in water passes through two gaps of the right size, for >>> example. In this case there is a medium present at each point through which >>> the waves are travelling, so the influence has something to transmit it, >>> and the resulting effect is easily explanied. >>> >>> So one's first guess is likely to be that the photons or electron in the >>> 2-slit experiment are just be interfering with each other in a similar >>> manner ... which wouldn't be paradoxical , of course ... except for the >>> additional fact that the intensity of the source can be turned down until >>> only one particle is passing through the apparatus at any given time - yet >>> even in this case, the interference pattern still appears (eventually). >>> >>> This situation appears in need of "urgent" explanation because the >>> apparent smallness of the particles in relation to the size of the >>> equipment suggests that a single electron or photon can't possibly "know" >>> about (be influenced by) a slit which it doesn't pass through, and which >>> is, relatively speaking, a large distance away. Assuming a photon passes >>> through the left hand slit, say, there is no known physical mechanism >>> available to tell it about the existence of the right hand slit. Yet it >>> will hit the screen in a position that is (statistically) determined by >>> what looks like interference between waves passing through both slits. >>> Hence the paradox. >>> >> >> I'd agree that's a component but why is that on its own a more urgent >> problem than the action at a distance problems with Newton's force when >> gravity? Or all those contradictions that accumulated in the late 19th >> century, that people felt were pretty incomprehensible and shocking, yet no >> one at any time started talking about the need for an 'interpretation' that >> made it all feel explained at any price? How come everyone was willing to >> leave all those problems wide open for up to hundreds of years, until not >> just an interpretation and explanation but scientific next generation >> theory, complete with all the traits science the way they knew and loved >> were explicit and visible. They had worse problems than this electron? On >> there own terms, as the knowledge they had, that was important to them, >> that was being upended by the contradictions that they faced. Was it worse >> for them, or where they just willing to live with it, because they knew >> they just had not accumulated enough knowledge yet to begin to answer the >> questions? >> > > I'm not sure who you're arguing with here, if anyone. All I said was that > the collapse of the wave function hasn't been directly observed. I guess > you've agreed with that comment, if you want to move on to something else. > > So, after that you moved on to what was the problem with the two slit > experiment. OK, so I've explained that, and since you've moved on from > that, I must assume you understood and agreed with the explanation. > > So what are you moving on to now? Why it was considered an urgent problem? > You mean as opposed to why everything else in science is considered an > urgent problem (phlogiston, planetary orbits, what the stars are, whether > the luminiferous aether exists, what happens to Maxwell's equations when > you travel at the speed of light, why the perihelion of Mercury advances, > how entropy can increase from time-symmetric molecular collisions, whether > the universe is expanding, what happens when an object collapses under its > own gravity, whether atoms exist...) Well, the short answer is that it > wasn't. Scientists worry about all sorts of problems, some have even been > burned at the stake for trying to solve them. > Liz - you would haver to be willing to identify a basic model of her w MWI came to ,.,.,as well as a large number of other properties, such mwi itself. You need to hace something like this in order to meaningfully undertake a process of deliberation whether and how MWI fits into scientific history. What you say above wouold be fine as a summary, but you seem to want to pass that for a way that everything is always urgent or whatever. You must see it's totally meaningless as a point like that? If you want to address the matter you've have to entify at least a few common propertties of theories, timelines, historirs......also of mwi too. Otherwise all you are going to be able to say in history model is words to the effect "Evertything is always the same". Urgent...it was always urgent! Just empty statements. Sorry liz...no intention to be harsh.
> >> The Interpretation Movement, was pretty unprecedented in that sense. >> > > It wasn't. Read up on the history of science and you will find plenty of > people worrying about stuff they couldn't explain. That is largely what > drives science, after all. > History of science is major long point of focus for me. If you believe there are parallels then please present one (make it from the major arterial threads of discovery). Please do, and we'll discuss it. It's up to you if you want to define all of science as an interpretation movement or identify yourself with a philosophy that s how science turns. All I m saying is that statements about unifirormity, everything the same, say absolulutely nothing of value. > > >> That an explanation,....a way to make sense of....was raised over >> everything else, including whether and what extent that explanation >> inherited any of the traits moHst fundamental, most unique, to science and >> science only. MWI hasn't got one. Not one. Or name one, and explain why >> it's fundamental to science, and unique to science and only science. >> > > As I understand it, the "QM interpretation movement" stalled for about 30 > years before the MWI came along. Everyone more or less agreed to "shut up > and calculate" but a lot of people were vaguely dissatisfied with the > situation (including Einstein).on > The truth is there a lot f misrepresenting all round in the various interpretation camp0s. In my view, givren no one had a good idea, shut up nf calculate was the least harmful approches The mwi people have created stereotypica, ideas about what was meant by shut up and calculate.ough how long long ius kong enough,. And right Liz, you have your contradiction with the interpretation movement. I'm saying science waits snd never hurries the pace. My assertion makes predicftions that we can check. So on my reading, there is absolutely nothing wrong with the idea of shut uo and calculate, so long as it reflects a real dearth of ideas how to procreedf. That is the way it's always been. The problem are ideas under pinninhg interpretations, You will not find that in scientific history...exceopt up failed cul de sacs. Prove me wrong. But please don't try to that by simple not setting anything up such that it is comparable. Or 'everythings is the same". You are saying What was implicit in that statement, was no one had good ideas for how push ahead. to what pacer things go Liz...science has always waited during periods like that, for the big ideas. Science waits. Hundreds of years if necessary. And science is willing to go aazingly slow. Science has never attached any priority nd And that' > Also, I suppose one of the "scientific" traits the MWI has (allegedly) is > that it takes the equation(s) of QM at face value, rather than postulating > extras like the collapse of the wave function - although whether it > succeeds or not is a different matter. There seems to be a lot of people > who think it doesn't. > > >> There are some parts you didn't mention unless I missed it.....like the >> way that pattern goes away when we try to look at see which slit the >> electron goes through. And the way the same pattern shows up even if >> electrons are fired one at a time. Even if the interval is a year or a >> million years. >> > > Yes I mentioned that. Here, to be exact - "which wouldn't be paradoxical , > of course ... except for the additional fact that the intensity of the > source can be turned down until only one particle is passing through the > apparatus at any given time - yet even in this case, the interference > pattern still appears (eventually)." > > > -- 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.
