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

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SUMMARY

The discussion centers on the energy of a photon, defined by the formula E = hν, where E represents energy, h is Planck's constant, and ν is frequency. The relationship between energy and momentum is further explored through the de Broglie equation, p = h/λ, leading to the conclusion that for relativistic particles, the energy-momentum-mass relationship is expressed as E = √((pc)² + (mc²)²). For photons, where mass (m) equals zero, this simplifies to E = pc. The discussion confirms that these relationships are measurable and not merely axiomatic.

PREREQUISITES
  • Understanding of Planck's constant (h) and its significance in quantum mechanics.
  • Familiarity with the de Broglie wavelength (λ) and its application in particle physics.
  • Knowledge of relativistic physics, particularly the energy-momentum-mass relationship.
  • Basic grasp of the concept of photons and their properties in quantum theory.
NEXT STEPS
  • Research the implications of Planck's constant in quantum mechanics and its applications.
  • Explore the derivation and applications of the de Broglie wavelength in particle physics.
  • Study the energy-momentum-mass relationship in detail, focusing on relativistic particles.
  • Investigate the properties of photons and their role in electromagnetic theory.
USEFUL FOR

Physicists, students of quantum mechanics, and anyone interested in the fundamental principles of energy and momentum in relation to photons and relativistic particles.

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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