
      [Screen shot of the energy eigenfunction describing the ISW first-excited state.]
The infinite square well (ISW) is an idealized model consisting of a point mass m inside an infinitely deep well of width a.  
	According to quantum mechanics, the energy eigenfunctions ψn(x) for a symmetric ISW are simple sinusoidal functions
 
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	The corresponding energy eigenvalues En scale as the principal quantum number n squared
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