Photons and the Uncertainty Principle

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SUMMARY

The discussion centers around the relationship between photons and the Heisenberg Uncertainty Principle, specifically the equation (delta)x(delta)p = h/4π. Participants explore the implications of this principle on the measurement of photons, questioning how the constant speed of light affects the uncertainty in position (delta)x and momentum (delta)p. The conclusion emphasizes that the momentum of a photon is not determined by its velocity but is instead directly proportional to its frequency, clarifying misconceptions about the relationship between these variables.

PREREQUISITES
  • Understanding of the Heisenberg Uncertainty Principle
  • Basic knowledge of quantum mechanics and elementary particles
  • Familiarity with the properties of photons and light
  • Concept of momentum in physics
NEXT STEPS
  • Study the Heisenberg Uncertainty Principle in detail
  • Learn about the relationship between frequency and momentum of photons
  • Explore the implications of quantum mechanics on particle behavior
  • Investigate the speed of light in different media and its effects on photon properties
USEFUL FOR

Physics students, quantum mechanics enthusiasts, and anyone interested in the fundamental properties of light and particles will benefit from this discussion.

Qbit42
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Using the meager physics knowledge I've scrapped together over my 19 year life span I've arrived at the following conundrum. It's more than likely that I'm entirely wrong, but I'd like to know why. Anyways here it goes.

First let me unviel my understanding of the universe, limited though it may be. Elementary particles exibit an phenomenon known as the uncertainty principal, which goes something like
(delta)x(delta)p = h/4(pie). A photon is one such elemetary particle. As far as my understanding of photons goes they are quantized bundles of light energy, which to me suggests that it would travel at the speed of light. It has been well established that the speed of light is constant for any particular medium. So my question is, if the speed of light is always a constant, that would mean that (delta)p is 0, making (delta)x infinity. This makes little sense to me since that would make it neigh impossible to ever find a photon. Also it would give rise to the following paradox. Since the speed of light varies in different substances, and the universe is not a homogeneous mixture of substances, we could never tell which substance a photon is actually traveling though (due to (delta)x being infinity). Since we can't tell what substance it is traveling though, we cannot say what its momentum truly is. Yet this uncertainty in momentum would allow (delta)x to come down from infinity, making it possible to discover which material the photon is in, thus allowing the momentum to be calculated precisely If the momentum is claculated precisely, then (delta)x again rises to infinity. You can see the paradox present here. Can someone please shed some light on this for me, no pun intended. :-p
 
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You are incorrect in stating that the momentum is definitely known. The momentum of a photon has nothing to do with its velocity; it is directly proportional to the frequency.
 
You are incorrect in stating that the momentum is definitely known. The momentum of a photon has nothing to do with its velocity; it is directly proportional to the frequency.

Oh really? Thanks!
 

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