'Quantum Mechanics'

This question is from the text book 'Quantum Mechanics' second edition by David J. Griffiths. (See attached file for full problem description) --- - Problem 3.35 - Coherent states of the harmonic oscillator... ---

Modern Physics: Energy, Compton wavelength, rest mass energy

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De Broglie Wavelengths

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Excited state atoms

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Interference fringes

If you punched a metal plate with two pinholes and illuminated them with light, would you see interference fringes if you used: (a) laser light, or (b) light from an LED (light emitting diode) ? (c) sunlight ? (d) spontaneous emission coming out the side of the He-Ne laser ?