Understanding the Energy of a Photon: A Closer Look at the Underlying Formula

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Discussion Overview

The discussion centers around the formula for the energy of a photon, exploring whether it is an accepted axiom or a measurable quantity. Participants examine the relationship between energy, momentum, and mass, particularly in the context of photons and relativistic particles.

Discussion Character

  • Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions whether the formula for photon energy should be taken for granted as an axiom.
  • Another participant asserts that the energy of a photon can be measured, suggesting empirical support for the formula.
  • A participant presents the formula E = hν and connects it to de Broglie's relation for momentum, proposing E = pc for photons.
  • Another participant introduces the general relationship for relativistic particles, E = √((pc)² + (mc²)²), noting that for photons, where mass m = 0, this simplifies to E = pc.

Areas of Agreement / Disagreement

Participants express differing views on whether the energy formula for photons is an axiom or a measurable quantity, indicating that multiple competing views remain in the discussion.

Contextual Notes

The discussion does not resolve the assumptions regarding the nature of the formula or its empirical validation, leaving some aspects open to interpretation.

AyoubEd
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please look at he underligned formula. is it a axiom we have to ake for granted ?
 

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No, we can and have measured this as far as I know.
 
I think i got it
E=h.v
-De broglie : p=h/(the wace longitude:L)
hence:
E=h.c/L=p.c
 
For relativistic particles, the general relationship between energy, momentum and mass is $$E = \sqrt {(pc)^2 + (mc^2)^2}$$ where m is the invariant mass (often called the "rest mass"). For photons, m = 0 which leads to E = pc.
 
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