Physical Interpretation of a Wave Packet: Single Beat Wavepacket

AI Thread Summary
The discussion centers on the expression for a wave packet in terms of a Fourier integral, which represents a continuous superposition of classical harmonic waves. The integral corresponds physically to a system with uncertain energy and momentum due to the superposition of various energy and momentum states. One participant notes that a wave packet can be seen as having distinct 'beats' when comprised of a single frequency. This interpretation aligns with concepts from introductory quantum mechanics. Overall, the conversation highlights the connection between wave packets and the uncertainty principle in physics.
quasar987
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In my wave final there was a quetion that went "Write the most general expression for a wave paquet in terms of a Fourier integral and explain what this integral corresponds to physically."

What would have you answered to the second part of the question?
 
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A continuous superposition (meaning integral wrt the wave vector) of (classical) harmonic waves (meaning complex exp of "i(kr-omega t)").

Daniel.
 
quasar987 said:
In my wave final there was a quetion that went "Write the most general expression for a wave paquet in terms of a Fourier integral and explain what this integral corresponds to physically."

What would have you answered to the second part of the question?

I'd probably have said that it corresponded to a system whose energy and momentum was "uncertain", because it was in a superposition of energy states (and a superposition of momentum states, too).
 
A wave whose 'beats' are infinitely far apart (i.e. the wavepacket is comprised of a single 'beat')?

This was the interpretation offered by one of my lecturers when I was studying introductory QM at uni.

Claude.
 
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