ajb Posted October 10, 2012 Share Posted October 10, 2012 I remember being taught Heisenberg's argument. I too was introduced to the principle via Heisenberg's argument, as I was introduced to atomic spectra via Bohr's model. Link to comment Share on other sites More sharing options...
swansont Posted October 10, 2012 Share Posted October 10, 2012 I too was introduced to the principle via Heisenberg's argument, as I was introduced to atomic spectra via Bohr's model. The difference for me was that I did not see the correct formulation of the HUP until grad school, and it wasn't until after I graduated that I ran across a discussion that really showed that Heisenberg's formulation was not the same thing as the QM one. So the observer effect explanation stuck with me a long time. But the Bohr model was shown to be wrong in QM, which followed pretty quickly in my classes. But that is a step that a lot of students (non-physics-majors) don't take — they see the Bohr model in an intro class and that's it. Link to comment Share on other sites More sharing options...
derek w Posted October 10, 2012 Share Posted October 10, 2012 From far enough away,an object of any shape will look and behave as a point-like object. And visa versa the closer you get to a point-like object the less it will behave like a point like-object and the more it will behave like an object with structure. 1 Link to comment Share on other sites More sharing options...
ajb Posted October 10, 2012 Share Posted October 10, 2012 The difference for me was that I did not see the correct formulation of the HUP until grad school, and it wasn't until after I graduated that I ran across a discussion that really showed that Heisenberg's formulation was not the same thing as the QM one. I think the formulation in terms of expectation values and standard deviations was part of the second QM course that I took, we discussed some issues a little more formally such as Dirac notation and so on. Link to comment Share on other sites More sharing options...
derek w Posted October 10, 2012 Share Posted October 10, 2012 If I look at a swarm of(e.g. bees) from a large enough distance,it would look like a single object,occupying a single point in space and time. However zooming in closer,my point like object would start to occupy many points in space and time.what I see is determined by how close I can look. Link to comment Share on other sites More sharing options...
Mike Smith Cosmos Posted October 13, 2012 Share Posted October 13, 2012 (edited) If I look at a swarm of(e.g. bees) from a large enough distance,it would look like a single object,occupying a single point in space and time. However zooming in closer,my point like object would start to occupy many points in space and time.what I see is determined by how close I can look. Like your Bee model ! As we are talking in analogies and metaphors. I have wrestled in my mind about the Heisenberg uncertainty principle , observer interference, etc. The simple way I have of containing the particle/wave /uncertainty conundrum in my head ( which is obviously not real ) is that "The Things" are like "birds" they fly about , hide places , sing and do their business all over the place in another realm ( the sky ,trees, etc) If you try and pin them down and examine them, they cant fly any more, and probably die on you. If you let them go and do the flying bit ,you don't see them for long and you don't know where they are. Obviously the metaphor breaks down as soon as it starts, but I always need some pictorial model to hang my thoughts on ( only the pure mathematicians seem to be able to abandon visualization and drift quite happily in the realms of number.) Edited October 13, 2012 by Mike Smith Cosmos Link to comment Share on other sites More sharing options...
derek w Posted October 14, 2012 Share Posted October 14, 2012 Like your Bee model ! As we are talking in analogies and metaphors. I have wrestled in my mind about the Heisenberg uncertainty principle , observer interference, etc. The simple way I have of containing the particle/wave /uncertainty conundrum in my head ( which is obviously not real ) is that "The Things" are like "birds" they fly about , hide places , sing and do their business all over the place in another realm ( the sky ,trees, etc) If you try and pin them down and examine them, they cant fly any more, and probably die on you. If you let them go and do the flying bit ,you don't see them for long and you don't know where they are. Obviously the metaphor breaks down as soon as it starts, but I always need some pictorial model to hang my thoughts on ( only the pure mathematicians seem to be able to abandon visualization and drift quite happily in the realms of number.) I tend to visualize a field of virtual particles that can oscillate between being a swarm of virtual particles where the energy is spread out,to being a real point like particle where all the energy is concentrated,the field of virtual particles collapsing to a single point like particle. Link to comment Share on other sites More sharing options...
Mike Smith Cosmos Posted October 14, 2012 Share Posted October 14, 2012 I tend to visualize a field of virtual particles that can oscillate between being a swarm of virtual particles where the energy is spread out,to being a real point like particle where all the energy is concentrated,the field of virtual particles collapsing to a single point like particle. Good one I like it! Link to comment Share on other sites More sharing options...
Mike Smith Cosmos Posted November 6, 2012 Share Posted November 6, 2012 (edited) Should the [current] inability to "measure" position and momentum mean that a particle at a moment in time does not have a given position and speed? Do we not all confuse ourselves by thinking that time is absolute. I thought this backdrop of absolute time was abandoned with quantum mechanics. When we bring a particles' activities into OUR time do we not make them perform as we want them to perform in our reality, with our bouncing, spinning, and whatever. Whereas left to their own quantum style of activity they behave different to our expectations. However I must say that " shut up and calculate " is no help always, particularly if we may not yet have the correct maths in our hands yet , to deal with some of these matters. Perhaps there is a more ephemeral maths aspect yet to be discovered that can bridge the gap between our reality and the quantum world. . Edited November 6, 2012 by Mike Smith Cosmos Link to comment Share on other sites More sharing options...
swansont Posted November 7, 2012 Share Posted November 7, 2012 However I must say that " shut up and calculate " is no help always, particularly if we may not yet have the correct maths in our hands yet , to deal with some of these matters. Perhaps there is a more ephemeral maths aspect yet to be discovered that can bridge the gap between our reality and the quantum world. How do you test to see if you have the correct maths, other than to test your model and see if it conforms to reality? Link to comment Share on other sites More sharing options...
chandragupta Posted November 7, 2012 Share Posted November 7, 2012 1349426008[/url]' post='705861']It is not our inability, the quantum world tells us we cannot. What quantum mechanics tells us that the particle will take all possible values of position and speed, until we try to measure one of these- it has all positions and speeds until we look at it! Even then everything is rather statistical and stated in terms of probability. Your above answer I am trying to visualize in a classical way. Could it be some like this :- some thing is not working. Owner of this thing has not made up his mind when & whom he is going to call to get this thing repaired. But here comes the son or daughter of the owner & starts to pester him by asking when he is going get the thing repaired ? So in order to stop the pestering ,he says 'o.k.,o.k. , I am calling now such & such person to get that thing repaired. In this classical analogy owner is the quantum & son or daughter is the observer & 'when & whom ' is the 'position & speed ' of the quantum. Have I got your thought right ? Link to comment Share on other sites More sharing options...
Mike Smith Cosmos Posted November 7, 2012 Share Posted November 7, 2012 (edited) How do you test to see if you have the correct maths, other than to test your model and see if it conforms to reality? It would strike me that there are some aspects of quantum behavior which confuse us all. We seek an understanding; can find many unsatisfying solutions; and thus continue to make predictions and carry out experiments so as to gain a certain amount of satisfaction , either by experimental results or by mathematical rigor. Although results do come by way of such things as Higgs boson discovery or by way of certain aspects of string theory mathematics. Yet still there is this feeling of a lack of satisfaction about the links across all sorts of things Quantum into our observational or contact reality. Might we ( or maybe some adept mathematician ) maybe develop some new form of transform which bridges the isolated quantum happenings to the larger material reality ( eg an up-to-date ephemeral LaPlace Transform or something ) I too was introduced to the principle via Heisenberg's argument, as I was introduced to atomic spectra via Bohr's model. Can you invent a new ephemeral transform which could link the isolated quantum world from the interfering reality world of Observation. Possibly taking our time out of the picture somehow ! . Edited November 7, 2012 by Mike Smith Cosmos Link to comment Share on other sites More sharing options...
swansont Posted November 7, 2012 Share Posted November 7, 2012 It would strike me that there are some aspects of quantum behavior which confuse us all. We seek an understanding; can find many unsatisfying solutions; and thus continue to make predictions and carry out experiments so as to gain a certain amount of satisfaction , either by experimental results or by mathematical rigor. Although results do come by way of such things as Higgs boson discovery or by way of certain aspects of string theory mathematics. Yet still there is this feeling of a lack of satisfaction about the links across all sorts of things Quantum into our observational or contact reality. Might we ( or maybe some adept mathematician ) maybe develop some new form of transform which bridges the isolated quantum happenings to the larger material reality ( eg an up-to-date ephemeral LaPlace Transform or something ) But whatever new model you come up with has to describe the experiments we've already done, which means the math has to be equivalent to what we already have. It has to give the same answer. Invoking some higher-level model doesn't change this. Link to comment Share on other sites More sharing options...
Mike Smith Cosmos Posted November 7, 2012 Share Posted November 7, 2012 (edited) But whatever new model you come up with has to describe the experiments we've already done, which means the math has to be equivalent to what we already have. It has to give the same answer. Invoking some higher-level model doesn't change this. The last time I did an Electronics Degree in Communications ( 1998-2002) we did some fairly hairy maths, what with Electro-Magnetic Wave Theory. The Maths teacher went through all sorts off transforms ( Fourier, Laplace and others). There was one that caught my fancy, The name of it escapes me. It went something like this : You put Y= s/1-s squared. There was a particular value of s or something, such that all positional values of Y, and X in the real plane , transposed to allways the exact same POINT in the s plane. INTERESTING. Also you could back transform into the real plane and end up ANYWHERE. Also interesting. I assume one can devise any sort of transform you want. What I was suggesting, but I am not a through and through mathematician , as I cannot, or am unable to let go of visual models easily. But I understand the principles of transforms as a method of being able to deal with difficult happenings in the Real plane in a simpler form in the 's' or whatever plane you want to call it. I am trying to suggest a transform that does not matter, interfere with the quantum world, or observe when undergoing the math transform. I understand this is providing a difficulty in getting information out of quantum computers. I also think it is causing many of us difficulties to get our head around various quantum events, or states. I still have a hunch that when we step from reality to the realm of the quantum world, we step from reality to probability. And when the "dice" comes down , BINGO we have reality, all the other possibilities are NOT real until the " dice" comes down on some other go in the probability spectrum. I' ve separated this last sentence out as its only a hunch and falls into the SPECULATION mode ( Clearly identified ) . . Edited November 7, 2012 by Mike Smith Cosmos Link to comment Share on other sites More sharing options...
LaurieAG Posted November 8, 2012 Share Posted November 8, 2012 (edited) But whatever new model you come up with has to describe the experiments we've already done, which means the math has to be equivalent to what we already have. It has to give the same answer. Invoking some higher-level model doesn't change this. What about the Compton wavelength (rest mass) and the reduced Compton wavelength (relative mass). Edited November 8, 2012 by LaurieAG Link to comment Share on other sites More sharing options...
Mike Smith Cosmos Posted November 8, 2012 Share Posted November 8, 2012 (edited) What about the Compton wavelength (rest mass) and the reduced Compton wavelength (relative mass). What is The Compton wavelength? Probably displaying my ignorance . Are you talking about X ray scattering . Edited November 8, 2012 by Mike Smith Cosmos Link to comment Share on other sites More sharing options...
swansont Posted November 8, 2012 Share Posted November 8, 2012 What about the Compton wavelength (rest mass) and the reduced Compton wavelength (relative mass). What about them? I still have a hunch that when we step from reality to the realm of the quantum world, we step from reality to probability. And when the "dice" comes down , BINGO we have reality, all the other possibilities are NOT real until the " dice" comes down on some other go in the probability spectrum. I' ve separated this last sentence out as its only a hunch and falls into the SPECULATION mode ( Clearly identified ) . Experiment has shown superposition effects to be real. States interfere with each other. That's one of the things about QM that does not appear in classical physics. Link to comment Share on other sites More sharing options...
chandragupta Posted November 8, 2012 Share Posted November 8, 2012 1352333235[/url]' post='712219']What is The Compton wavelength? Probably displaying my ignorance . Are you talking about X ray scattering . Link to comment Share on other sites More sharing options...
LaurieAG Posted November 8, 2012 Share Posted November 8, 2012 (edited) The difference between the two is 2 x Pi and if you divide the latest quantum perceived 'dark' matter/energy by 2 x Pi there is very little 'dark' matter/energy. I read many of the latest 'dark' matter papers and while I could only find one that derived from the non reduced form down to the reduced form I could not find a single paper that went back to the non reduced form. It is very strange as the difference is quite clear. http://en.wikipedia....pton_wavelength Relationship between the reduced and non-reduced Compton wavelength The reduced Compton wavelength is a natural representation for mass on the quantum scale. Equations that pertain to mass in the form of mass, like Klein-Gordon and Schrödinger's, use the reduced Compton wavelength. The non-reduced Compton wavelength is a natural representation for mass that has been converted into energy. Equations that pertain to the conversion of mass into energy, or to the wavelengths of photons interacting with mass, use the non-reduced Compton wavelength. ... The Planck mass is special because the reduced Compton wavelength for this mass is equal to half of the Schwarzschild radius. This special distance is called the Planck length (). This is a simple case of dimensional analysis: the Schwarzschild radius is proportional to the mass, whereas the Compton wavelength is proportional to the inverse of the mass. Edited November 8, 2012 by LaurieAG Link to comment Share on other sites More sharing options...
swansont Posted November 9, 2012 Share Posted November 9, 2012 The difference between the two is 2 x Pi and if you divide the latest quantum perceived 'dark' matter/energy by 2 x Pi there is very little 'dark' matter/energy. I read many of the latest 'dark' matter papers and while I could only find one that derived from the non reduced form down to the reduced form I could not find a single paper that went back to the non reduced form. It is very strange as the difference is quite clear. http://en.wikipedia....pton_wavelength It's a matter of convenience, in the context of whether the equation has factors of 2*pi in it or not. e.g. Schrödinger's equation does. It's similar to whether you use Planck's constant or the reduced Planck's constant. [math]\hbar\omega[/math] vs. [math]h\nu[/math] Link to comment Share on other sites More sharing options...
Mike Smith Cosmos Posted November 9, 2012 Share Posted November 9, 2012 (edited) Experiment has shown superposition effects to be real. States interfere with each other. That's one of the things about QM that does not appear in classical physics. I thought the superposition was only real and true if you did not actually observe one of the superposition particles. And that if you did attempt to observe one of the particles, then the probability wave collapsed and the interference collapsed, and we were back to only , one real position of the particle or the other position BUT NOT BOTH. . Edited November 9, 2012 by Mike Smith Cosmos Link to comment Share on other sites More sharing options...
swansont Posted November 9, 2012 Share Posted November 9, 2012 I thought the superposition was only real and true if you did not actually observe one of the superposition particles. And that if you did attempt to observe one of the particles, then the probability wave collapsed and the interference collapsed, and we were back to only , one real position of the particle or the other position BUT NOT BOTH. There are results that are only true if the particles were in a superposition, rather than being in a definite state, prior to measurement. Link to comment Share on other sites More sharing options...
Mike Smith Cosmos Posted November 9, 2012 Share Posted November 9, 2012 (edited) There are results that are only true if the particles were in a superposition, rather than being in a definite state, prior to measurement. Yes, but am I not correct that a knowledge that the superpositions exist, yet not being observed is one thing. But then trying to check or measure the state of one of the two particular superposition states will knock both particles out of their superposition mode into a single state mode ( if that's the right way of describing it ). What I have just stated sounds a bit like Shroenigers cat. Its neither dead or alive while the box is closed. But when you open the box it has to be either dead or alive according to the radio active release at the time, which can/is random. Bingo Quad et demonstratem QED ( unless of course Shroeneger was wrong !) Get out of that one, you son of ........ ! . . Edited November 10, 2012 by Mike Smith Cosmos Link to comment Share on other sites More sharing options...
Mike Smith Cosmos Posted November 10, 2012 Share Posted November 10, 2012 (edited) Yes, but am I not correct that a knowledge that the superpositions exist, yet not being observed is one thing. But then trying to check or measure the state of one of the two particular superposition states will knock both particles out of their superposition mode into a single state mode ( if that's the right way of describing it ). What I have just stated sounds a bit like Shroenigers cat. Its neither dead or alive while the box is closed. But when you open the box it has to be either dead or alive according to the radio active release at the time, which can/is random. Bingo Quad et demonstratem QED ( unless of course Shroeneger was wrong !) . Get out of that one, you son of a ........ ! . . Edited November 10, 2012 by Mike Smith Cosmos Link to comment Share on other sites More sharing options...
swansont Posted November 10, 2012 Share Posted November 10, 2012 Yes, but am I not correct that a knowledge that the superpositions exist, yet not being observed is one thing. But then trying to check or measure the state of one of the two particular superposition states will knock both particles out of their superposition mode into a single state mode ( if that's the right way of describing it ). What I have just stated sounds a bit like Shroenigers cat. Its neither dead or alive while the box is closed. But when you open the box it has to be either dead or alive according to the radio active release at the time, which can/is random. Yes, that's right. Link to comment Share on other sites More sharing options...
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