Light wave or particle

1
Light -wave or particle?
PHYSICS 1

• Somnath Bharadwaj and Pratik Khastgir,
  Department of Physics and Meteorology, IIT
  Kharagpur, 721 302 India
• http//www.cts.iitkgp.ernet.in/phy1/

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The Compton Effect
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Photon electron collision
4
Conservation of Energy
5
Conservation of momentum
x
y
Square and add
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Momentum and Energy
7
Change in wavelength
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Compton Effect
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Wave nature of particles
De Broglie in 1924 Every particle has an
associated wave
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Dispersion Relation
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Interpretation?

• Particle is localized
• Wave is defined everywhere
• Momentum is known
• No position energy

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Electron diffraction
Davison and Germer 1927 Verified wave nature of
particles