Intensity of Light using Quantum theory

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SUMMARY

This discussion focuses on the quantum theory predictions regarding the intensity of light at a glass-air boundary, specifically addressing the behavior of single photons. It establishes that while classical physics predicts approximately 8% reflection, quantum mechanics indicates a 4% reflection probability for a single photon, with a 96% chance of transmission through the glass. The conversation emphasizes that the behavior of photons is described by a wave function, which reflects probabilistic outcomes rather than total unpredictability. Participants suggest clarifying the explanation of photon behavior to enhance understanding.

PREREQUISITES
  • Quantum mechanics fundamentals
  • Wave-particle duality of light
  • Understanding of wave functions
  • Basic principles of reflection and transmission at boundaries
NEXT STEPS
  • Study the concept of wave functions in quantum mechanics
  • Explore the implications of wave-particle duality on light behavior
  • Investigate the mathematical formulation of reflection and transmission coefficients
  • Learn about quantum probability and its applications in photon behavior
USEFUL FOR

Students of physics, quantum mechanics enthusiasts, and researchers interested in the behavior of light at material boundaries will benefit from this discussion.

Seven of Nine
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Homework Statement


Approximately 4% of the intensity of light is reflected at a glass-air boundary. Classically one expects roughly 8% of light to be reflected from a thin glass plate (4% at the front and back boundary). Outline briefly what quantum theory predicts for a single photon instead of a light beam, in particular, say how this differs from the classical prediction.

2. The attempt at a solution
If light shines on an imperfectly transparent sheet of glass it may happen that 96% of light transfers through the glass, this makes sense if light were a wave, as the wave splits and a smaller wave is reflected back. But light is considered as a steam of particles so the glass has a 96% chance of being transmitted and 4% chance of being reflected. The behaviour of the photon is totally random and unpredictable. It is defined as a wave function. A particle when not being measured or located takes the form of a field of probable locations some being more probable or as likely than others.

Is that right?
 
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Your answer is not wrong but it is not clear.
They are demanding the behavior of a single photon. So I would advise to clean up this part:
Seven of Nine said:
If light shines on an imperfectly transparent sheet of glass it may happen that 96% of light transfers through the glass, this makes sense if light were a wave, as the wave splits and a smaller wave is reflected back. But light is considered as a steam of particles so the glass has a 96% chance of being transmitted and 4% chance of being reflected.
I couldn't quite get what you wanted to say.

Then I would skip that part:
Seven of Nine said:
The behaviour of the photon is totally random and unpredictable.
since it is not correct. It is true that the behavior follows a probabilistic behavior, but that does not mean that it is "totally unpredictable". However, saying that It is described by a wavefunction suffices. And the last sentence is also good.

When you correct the first part maybe move it after the second one. You would then have explained the general quantum behavior and moved on to the specific problem.
 

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