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Offline McQueen

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The Three Polariser Experiment
« on: 09/04/2016 22:32:12 »
One of the experiments that is claimed as an infallible proof of the wave/particle duality theory of Quantum Mechanics is the three polariser experiment. In this experiment (see Diag A below) a light source is shone through a horizontally oriented polariser and passes on to a light detector.  This means that only horizontally oriented light can pass through the filter, the vertical content is eliminated. In this instance a strong signal is detected by the detector:



In the second stage of the experiment, a second vertical polariser is put in place between the horizontal polariser and the light detector. The vertical polariser blocks out all vertical content.  In this case the result is that no light passes through to the detector:



In the third stage a diagonal polariser replaces the filter placed between the hortizontal ( or vertical) polariser and in this case  some light passes through to the detector:



This makes  sense, because if the vertical polariser blocks all horizontal oriented light and the horizontally oriented polariser blocks all horizontal light, no light should get through to the detector and this is proved by the experiment.  In the same way when the vertical (or horizontal) filter is replaced by the diagonal filter some light gets through to the detector, since obviously some of the vertical light can now get through, this is also perfectly acceptable and is verified through the experimental results.

Here is the eureka factor in the experiment. if a diagonally oriented polariser is now placed between the vertical polariser and the horizontal polariser, some light is seen to get through to the detector. How can this happen? The vertical component, the horizontal component  AND the diagonal component have all been blocked, how then is it possible for light to still get through to the detector ?



The Quantum Physics Explanation

Letís start with the A polarizer in the back. It prepares the  photons in the vertical polarization state | v >. If we now had just polarizer B, it would measure for horizontal photons. None are coming through A, so no photons get through B.
When we interpose C at the oblique angle, it measures for diagonal photons. The vertically polarized photons coming through A can be considered in a superposition of states at a 45 degree angle and a -45 degree angle. Photons at -45 degrees are absorbed by C. Those at +45 degrees pass through C.
C makes a measurement of 45 degree photons. It can also be viewed as a preparation of 45 degree photons. Only half the photons come through polarizer C, but they have been prepared in a state of diagonal polarization | d >.
The original vertical photons coming through A had no chance of getting through B, but the diagonal photons passing through C (half the original photons) can now be regarded as in a linear superposition of vertical and horizontal photons, and the horizontal photons can now pass through B. Those vertically polarized will get absorbed by B, as usual.
Recall from equation (1) that | d > is a superposition of the basis vectors | v > and | h >, with coefficients 1/√2, which when squared give us probabilities 1/2. Fifty percent of these photons emerging from C will pass through B. One quarter or 25% of the original A photons make it through.
This happens if we send just one photon through at a time, just as with the two-slit experiment. Just as we can not say that the photon passes through slit A or B (only probabilities are moving in von Neumannís process 2), we cannot say that our photons are in one state or another. They are in the mysterious linear combination that can collapse instantaneously into one state when a measurement is made.

The GAT Gestalt Aether Theory Explanation:
(Note edited because based upon wrong assumption)

The earlier statement that a diffraction grid could be used as a polariser, was erroneous, although certain polarisers are made with metal wires embedded into them, that can be used as linear polarisers, these polarisers might not work well in the three polariser experiment. A polariser is an optical filter that passes light of a specific polarization and blocks waves of other polarizations. It can convert a beam of light of undefined or mixed polarization into a beam with well-defined polarization, polarized light. All polarisers are anisotropic in construction,   meaning that they allow  light to pass in a single direction as opposed to say a pane of glass that will allow light to  pass through it  isotropically.  A polariser will allow only light of a single polarisation to pass, light that is polarised in other directions is absorbed.

Thus a linear polariser that is placed vertically in front of a light source will transmit only the vertical component of light, similarly if the same polariser is turned 900 and placed in front of the light source it will allow only the horizontal component of light to pass. Therefore the direction of polarisation with respect to the beam is determined by the orientation of the polariser with respect to the beam (the direction of the polarisation of the beam coincides with the direction of the axis of the polariser). It should be noted that if a polariser is placed in front of a light source , the intensity of the light source will be reduce by 50%.   If a vertical polariser is placed in tandem with a horizontal polariser no light will be allowed to pass, since only the vertical component of the light source is allowed through the first polariser and thus there is no horizontally polarised light available to pass through the second horizontally aligned polariser. 

If, however, a diagonally oriented  polariser is placed  in front of the vertical polariser, it is found that depending on the angle of the diagonally oriented polariser, some  light is seen to pass through both filters.  Finally if the diagonal filter is placed between the vertical and horizontal filters, some light is again seen to pass through. Thus when the diagonal polarizer is in place,  it will let half of the vertically polarised photons pass through and these transmitted photons will then be diagonally polarized. When these diagonally polarized photons arrive at the horizontal polarizer,  half of them will get throughósince strictly speaking they are not a component of the vertically polarised light.

This experiment was well known in classical physics much before the time Quantum Mechanics was invented. What is new is that Quantum Mechanics introduced the concept of light in the form of photons being absorbed and re-emitted on its way through the material of the polariser. The classical explanation had to do with the propagation of a wave through the polariser. However, the Quantum Mechanics explanation that the result of the three polariser experiment is due to the superposition of the wave function is questionable, since the results of the three polariser experiment seems to depend not so much on superimposition of the wave function but rather on the physical properties of the polariser .

Thus the Gestalt Aether Theory concludes that the results of the three polariser experiment are due to the inherent physical properties of the polariser. This means that the vertically oriented photons that are transmitted through the first polariser are able to pass through the diagonally oriented polariser because the physical properties of the polariser are strongly anisotripic, allowing polarisation of one direction only to pass through. Since the vertically polarised photons share some aspects in common with the diagonally oriented photons, some of them are allowed to pass through in keeping with the relationship  f8a6134aaab2a44338aef16e7ecf2c1a.gif where I is the intensity and 7b7f9dbfea05c83784f8b85149852f08.gif is the angle at which the diagonal polariser is placed. If now the horizontal polariser is placed in a position behind the diagonally placed polariser since the diagonally polarised photons share some aspects in common with the horizontally polarised photons,  some of the light is allowed to pass through at a reduced intensity equal to 2ba59899031ba5d34b63b37d108d6ffc.gif.  In other words the diagonally polarised photons are neither vertically oriented nor horizontally oriented but share properties of both.

In what way does this differ from The Quantum Mechanics explanation, for one thing the Quantum mechanics explanation does not place much importance on the physical properties of materials preferring instead to follow a mathematical explanation that was influenced by the concept of wave particle duality.
« Last Edit: 11/04/2016 03:48:38 by McQueen »


 

Offline Thebox

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Re: The Three Polariser Experiment
« Reply #1 on: 10/04/2016 08:55:22 »
One of the experiments that is claimed as an infallible proof of the wave/particle duality theory of Quantum Mechanics is the three polariser experiment. In this experiment (see Diag A below) a light source is shone through a horizontally oriented polariser and passes on to a light detector.  This means that only horizontally oriented light can pass through the filter, the vertical content is eliminated. In this instance a strong signal is detected by the detector:



In the second stage of the experiment, a second vertical polariser is put in place between the horizontal polariser and the light detector. The vertical polariser blocks out all vertical content.  In this case the result is that no light passes through to the detector:



In the third stage a diagonal polariser replaces the filter placed between the hortizontal ( or vertical) polariser and in this case  some light passes through to the detector:



This makes  sense, because if the vertical polariser blocks all horizontal oriented light and the horizontally oriented polariser blocks all horizontal light, no light should get through to the detector and this is proved by the experiment.  In the same way when the vertical (or horizontal) filter is replaced by the diagonal filter some light gets through to the detector, since obviously some of the vertical light can now get through, this is also perfectly acceptable and is verified through the experimental results.

Here is the eureka factor in the experiment. if a diagonally oriented polariser is now placed between the vertical polariser and the horizontal polariser, some light is seen to get through to the detector. How can this happen? The vertical component, the horizontal component  AND the diagonal component have all been blocked, how then is it possible for light to still get through to the detector ?



The Quantum Physics Explanation

Letís start with the A polarizer in the back. It prepares the  photons in the vertical polarization state | v >. If we now had just polarizer B, it would measure for horizontal photons. None are coming through A, so no photons get through B.
When we interpose C at the oblique angle, it measures for diagonal photons. The vertically polarized photons coming through A can be considered in a superposition of states at a 45 degree angle and a -45 degree angle. Photons at -45 degrees are absorbed by C. Those at +45 degrees pass through C.
C makes a measurement of 45 degree photons. It can also be viewed as a preparation of 45 degree photons. Only half the photons come through polarizer C, but they have been prepared in a state of diagonal polarization | d >.
The original vertical photons coming through A had no chance of getting through B, but the diagonal photons passing through C (half the original photons) can now be regarded as in a linear superposition of vertical and horizontal photons, and the horizontal photons can now pass through B. Those vertically polarized will get absorbed by B, as usual.
Recall from equation (1) that | d > is a superposition of the basis vectors | v > and | h >, with coefficients 1/√2, which when squared give us probabilities 1/2. Fifty percent of these photons emerging from C will pass through B. One quarter or 25% of the original A photons make it through.
This happens if we send just one photon through at a time, just as with the two-slit experiment. Just as we can not say that the photon passes through slit A or B (only probabilities are moving in von Neumannís process 2), we cannot say that our photons are in one state or another. They are in the mysterious linear combination that can collapse instantaneously into one state when a measurement is made.

The GAT Gestalt Aether Theory Explanation:

In order to understand how polariser filters  work, consider a vertical polariser, it is a film with vertical lines etched onto it. The etched lines absorb all light coming towards them while the transparent areas let the light through. This has the effect of polarising the light, the light is now transmitted in narrow vertical stripes.



If this vertically polarised light is now sent through a similarly constructed horizontal polariser, then  no light would get through to the detector since the vertical lines of light that were let through the first filter are now being blocked by the horizontal lines in the second filter. 



Consider now the inclusion of a diagonal filter, this would let some of the light from the vertical filter through and slightly less  light through  the horizontal filter. The actual amount of light would depend on the orientation of the filter, anywhere from between 22.5 degrees and below 45 degrees would let light through, more light would be passed at 22.5 degrees than at 45 degrees.
If on the other hand the diagonal filter were placed behind both the vertical and horizontal filters, no light would pass through  it and no light would reach the light detector.
The GAT Theory therefore observes the same principles of light (photons) moving through matter, namely absorption and emission.  It is not necessary to change light into a wave and back into a photon, it retains the same soliton formation, namely that of a wave packet. The soliton formation is induced through the polarisation of bands of energy emitted by an electron, resulting in a solenoidal field being formed around the bands of energy. Since the bands of energy are separated by a di-electric, they form a condensor capable of storing energy. Thus the photon as envisaged by GAT is a true wave packet that is a synthsis of a wave and a particle somewhat similar to a soliton on a micro scale but with a far clearer definition.

This illustrates the fact that when one explanation can account for observed phenomena there is no point in looking for more complicated explanations.


Observer effect
 

Offline hamdani yusuf

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Re: The Three Polariser Experiment
« Reply #2 on: 14/04/2016 05:53:37 »
This problem is usually solved using Jones vector and Jones matrix. Basically, after a linear polarization, the light is aligned with polarizer's axis. In three polarizers case, the light after the first polarizer is horizontally oriented with half intensity (assuming that the original light is unpolarized). After the second polarizer, the light is diagonally oriented with a quarter of original intensity. After the last polarizer, the light is vertically oriented with 1/8 intensity.
 

Offline McQueen

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Re: The Three Polariser Experiment
« Reply #3 on: 15/04/2016 05:11:08 »
Absolutely, as far as the intensity is concerned. An explanation involving photons is what is needed though. With photons (According to GAT) it is the physical construction of the polariser that influences the results more than anything else.
« Last Edit: 15/04/2016 05:13:17 by McQueen »
 

Offline hamdani yusuf

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Re: The Three Polariser Experiment
« Reply #4 on: 15/04/2016 10:29:51 »
Absolutely, as far as the intensity is concerned. An explanation involving photons is what is needed though. With photons (According to GAT) it is the physical construction of the polariser that influences the results more than anything else.
According to GAT, what is the polarization state of the photon after each polarizer, especially after the diagonally oriented one?
 

Offline McQueen

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Re: The Three Polariser Experiment
« Reply #5 on: 16/04/2016 06:43:42 »
The only polarisation that a photon has is the polarisation that it receives during its formation, this is what contributes to its soliton or wave packet like attributes:


Gestalt Aether Theory holds that in the three polariser experiment, the results are due to the physical properties of the polariser.  All polarisers are strongly anisotropic, meaning that they allow  light  (photons) through in only one direction. Light from most sources is not coherent therefore it will be travelling in all directions. In GAT this would be pictured as lines of photons being emitted from electrons going in all directions. The polariser allows through only those photons that arrive in a vertical orientation and blocks all other orientations. If the polariser is placed at a diagonal to the incoming light (photons) it allows through some vertical and some horizontally oriented photons. To make this clearer, it is necessary to remember that GAT does not accept the existence of single individual photons, this means that it is a network or grid of photons. When imagining 'vertical' light being allowed through, imagine the polariser as forming narrow vertical lines that allow some (50%) of the light through.

 If the polariser is turned 90 degrees so that the lines are now horizontal only the horizontal component (50%) is let through. If the polariser is oriented diagonally then some of the horizontal and some of the vertical (25%) component of the light is let through.
 

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Re: The Three Polariser Experiment
« Reply #5 on: 16/04/2016 06:43:42 »

 

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