Quantum concepts

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Quantum concepts

• 6/7/03

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Holes in classical physics

• Stability of atoms
• Photo-electric effect in vacuum tubes
• Atomic spectra
• .more

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Fix 1 waves are particles

• Einsteins relation
• These particles (photons) have no mass
• But,but,but We tend to think of a particle as
  having a location. How does that relate to a
  wave of a single frequency, n, which is
  infinitely long?
• Explains the photoelectric effect

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Fix 2 particles are waves

• Bohrs postulate quantization of angular
  momentum
• De Broglie postulatea new wave
• .

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Equivalence of Bohr and DeBroglie
Require n waves to go around orbit
Substitute p mvr
Explains atomic stability and atomic spectra.
Qualitatively
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But,but,but.

• What about the position of a particle???
• You can only localize a wave by making it up from
  a variety of frequencies (wavelengths)
• Heisenberg uncertainty principle

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Schroedinger wave equation
Where
is a probability density.