Re: Speed limit at C a misconception?

don@xxxxxxxxxxxxxx (Don Klipstein) wrote in
news:slrndgg7mm.i2q.don@xxxxxxxxxxxxxx:

> In article <11gf3j7g3gkuh59@xxxxxxxxxxxxxxxxxx>, Skywise wrote:
<Snipola>

>>After all, are not concepts like phase or group velocity just
>>mathematical constructs? They aren't "real", right?
>
> "Phase Velocity" and "Group Velocity" are real!
>
> "Group Velocity" refers to speed of a pulse of a cluster of waves!
>
> "Phase Velocity" refers to speed of crest-trough-defined waves within a
> pulse, when that is different from velocity or speed of any definable
> cluster or modulation of such waves!
>
> - Don Klipstein (don@xxxxxxxxx)

Ok (I think). So how does this work with a single photon?

Brian
--
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