How Many Photons in a Light Wave

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The discussion explores the relationship between photons and light waves, questioning whether a single photon equates to a light wave or is merely a part of it. It clarifies that a single photon can be considered a quantum of light, while a light wave represents a broader concept encompassing many photons. The conversation also touches on the nature of light pulses, suggesting that true monochromatic light would theoretically extend infinitely in time. Additionally, it discusses the possibility of sending a pulse through a medium and emerging with a continuous wave, raising questions about photon absorption and transmission. Understanding these concepts is essential for grasping the dual nature of light in quantum mechanics.
peter.ell
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I was just wondering how the concept of a single photon is compared to the concept of a light wave.

Is a single photon equivalent to a single light wave, or is a single photon just a tiny instantaneous part of a light wave? That is, if a single light wave of a given wavelength strikes a surface, would that surface respond as if only one photon hit it, or a stream of photons all hitting it with the same frequency as the light wave?

Or am I completely mis-understanding this and it's neither of these two? Please help me understand this conceptually.

Thank you so much!
 
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A single photon is what you would call a light wave, and vice versa.
 
Excuse me if I make a bunch of over-simplified statements.

Does a single photon have a beginning and an end? Whenever I think of light pulses I think of the localization in space (or time) as being due to the superposition of many modes closely spaced in frequency. If the light were truly monochromatic it would have to extend infinitely in time. I can send the pulse through an absorptive medium such that most of the light gets absorbed every time. If I repeat this enough times, for one of these pulses everything is absorbed except for a single photon (hv of energy). Then is it theoretically possible to send a pulse into a material and get a continuous wave out the other side?
 

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