To what significance is the two different paths of the light?

In summary, the experiment involves a H filter and a +45◦/ − 45◦ loop (half-wave plate) with two branches. The output of the H filter is horizontally polarized light, which can be represented by an equation: Output = (Probability amplitude for horizontal polarization)^2. This is due to the interference of two paths with different polarization orientations, resulting in the cancellation of diagonal polarization. The significance of the two paths lies in their interference, which allows for the selection of specific polarization orientations.
  • #1
bemigh
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Hey guys,
I have a problem with a polarization question...
Consider the experiment H filter ← +45◦/ − 45◦ loop ← V photon. What is the output of
the H filter? Write down an equation describing this outcome, in terms of the probability amplitudes
for each step. Note that the +45◦/ − 45◦ loop has two branches!

Now, I can't get my head around the fact that the result would be 0. A 45/-45 loop would just recombine the polarized like together, that's what a loop does. So therefore the light when reaching the filter would just be V photon, and none would pass through.
To what signifigance is the two different paths of the light?
Any opinions is appreciated
Cheers
 
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  • #2


Hello there,

Thank you for your question. I understand your confusion about the outcome of this experiment. Let me provide some insights that may help clarify things for you.

First, let's start by defining some terms. Polarization refers to the orientation of the electric field of a light wave. It can be represented by arrows pointing in different directions, with the direction of the arrow indicating the orientation of the electric field. In this experiment, the H filter is a polarizing filter that only allows light with horizontal polarization to pass through.

Now, let's look at the experiment itself. The +45◦/ − 45◦ loop refers to a half-wave plate, which is a device that can rotate the polarization of light by 45 degrees. In this case, the half-wave plate is oriented at +45 degrees and -45 degrees, forming two branches. The V photon refers to vertically polarized light.

So, what happens when the V photon reaches the half-wave plate? As you correctly stated, the light will split into two paths, with one path going through the +45 degrees branch and the other going through the -45 degrees branch. This means that the light will have two different polarization orientations when it reaches the H filter - one with horizontal polarization and one with diagonal polarization.

Now, here comes the significance of the two different paths. When these two paths recombine at the H filter, they will interfere with each other. This interference will result in a cancellation of the diagonal polarization, leaving only the horizontal polarization to pass through the H filter. Therefore, the output of the H filter will be horizontally polarized light.

To write this in terms of probability amplitudes, we can use the following equation:

Output = (Probability amplitude for horizontal polarization - Probability amplitude for diagonal polarization) x (Probability amplitude for horizontal polarization)

Since the probability amplitude for diagonal polarization is equal to the probability amplitude for vertical polarization (since the half-wave plate rotated the polarization by 45 degrees), this equation simplifies to:

Output = (Probability amplitude for horizontal polarization)^2

I hope this helps to clarify the outcome of the experiment and the significance of the two different paths. If you have any further questions, please don't hesitate to ask. Good luck with your experiment!
 

FAQ: To what significance is the two different paths of the light?

1. What is the significance of the two different paths of light?

The significance of the two different paths of light is related to the concept of interference. When light travels through two different paths and then combines, it can either reinforce or cancel out each other depending on the phase of the light waves. This can result in patterns of dark and bright spots, which has important applications in fields such as optics and quantum mechanics.

2. How does the difference in path affect the interference of light?

The difference in path can affect the interference of light by altering the phase relationship between the two light waves. If the two paths have a difference of half a wavelength, the waves will be out of phase and will cancel each other out. But if the paths have a difference of a whole wavelength, the waves will be in phase and will reinforce each other, resulting in a bright spot.

3. Can you give an example of a real-life application of two different paths of light?

One example of a real-life application of two different paths of light is in the Michelson Interferometer, a scientific instrument used to measure small changes in distance. It works by splitting a beam of light into two paths, bouncing them off mirrors and then recombining them. The interference pattern of the combined light can reveal tiny changes in the distance between the mirrors, making it useful in fields such as geology and astronomy.

4. How does the behavior of light in two different paths relate to the wave-particle duality of light?

The behavior of light in two different paths highlights the wave-like nature of light. When light travels through the two paths, it exhibits interference patterns characteristic of waves. However, when the light is observed at a specific point, it behaves like a particle, demonstrating the wave-particle duality of light.

5. Can the two different paths of light be used to create color?

Yes, the two different paths of light can be used to create color through the process of diffraction. When white light passes through two narrow slits, it splits into different wavelengths, creating a rainbow-like pattern. This phenomenon is known as diffraction grating and is used in devices such as spectrometers to analyze the composition of light sources.

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