Does a photon have energy density?

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Discussion Overview

The discussion centers around the concept of energy density in relation to photons. Participants explore the nature of photons, their behavior, and how energy density applies to them, including questions about their spatial characteristics and implications in the context of light propagation.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants assert that photons have energy density, referencing the energy density of electromagnetic fields.
  • There is confusion regarding the term "energy density," with some participants questioning its relevance to photons, suggesting that photons are better understood as probability functions or point particles.
  • One participant raises a question about calculating the separation between photons in a light beam, indicating a desire for a quantitative understanding.
  • Another participant expresses uncertainty about how a point-like particle can possess a wavelength, which implies some form of spatial extension.

Areas of Agreement / Disagreement

Participants express differing views on the applicability and meaning of energy density in relation to photons, indicating that the discussion remains unresolved with multiple competing perspectives.

Contextual Notes

There are limitations in the discussion regarding the definitions of energy density and the physical characteristics of photons, including their spatial properties and the uncertainty surrounding elementary particles.

member 141513
Does a photon have energy density??

can anyone help me what a photon behaves when talking about energy density?
it seems that photon just travel through time but not space ,or I am wrong?
can anyone help? thanks so much~~
 
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yes a photon has energy density.

Don't understand the first part of your question: Are you sure you mean energy density??
See here http://en.wikipedia.org/wiki/Energy_density#Energy_density_of_electric_and_magnetic_fields

for the energy density of an electromagnetic field.

Since a photon is a probability function and perhaps also viewed as a point particle, "energy density" doesn't have a lot of value ...No one knows the physical size of any elementary particles...it's "uncertain"...

Have you thought about light (on form of photons) traveling from the sun to the earth??
Light travels to us here on Earth over a period of minutes at an observed velocity close to "c".
 


Naty1 said:
Since a photon is a probability function and perhaps also viewed as a point particle, "energy density" doesn't have a lot of value ...No one knows the physical size of any elementary particles...it's "uncertain"...

I am wondering how a point like particle can have a wavelength. Wavelength implies spatial extension.

Best wishes

DaTario
 

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