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Hecht

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@Constant314: This is a direct quote from Hecht,

Since, as we have learned, E is considerably more effective at exerting forces and doing work on charges than is B, we shall refer to E as the optical field and use Eq. (3.46) almost exclusively.

Eq. 3.46 being an expression for irradiance expressed in terms of E. The previous equation, 3.45, gives the same thing in terms of B. SpinningSpark 08:08, 14 May 2022 (UTC)[reply]

I take that as an off-hand remark. I will elaborate my point of view later today. Constant314 (talk) 13:43, 14 May 2022 (UTC)[reply]
Further elaborating, Jackson also says the magnetic field does no work. I suppose in a classical sense, it is true. If you have a charged partial that is not accelerated, then in its frame of reference, the magnetic field does nothing. The particle only feels the E-field. However, both the E-field and the B-field in the lab frame of reference contribute to the E-field in the particle's frame of reference. I think that it is an artificial distinction that should not be in the article. We know that in the lab frame of reference, work done is proportional to E X B. That may be Hecht's justification, but the real reason is that the E-field has been used in a million or so other publications. Using the E-field is the DeFacto standard. Constant314 (talk) 15:55, 14 May 2022 (UTC)[reply]
As I said in the merge discussion, I don't think Hecht meant this to be taken as a definition, only as a justification for the form of expressions he is using.
By the way, I've now read through the earlier chapters of Hecht and can't find where it is supposed "we have learned" this. I assumed when I read it he was referring to the fact that the electric force around charges is the fundamental force, and the magnetic force is a kind of "left-over" auxilliary force due to charge motion. But this chapter is discussing e-m waves where both components are of equal importance so I'm a bit baffled why he makes this statement at this point (other than to state which form he is using from that point forwards).
I'm going to nominate this for deletion, I assume you support that as you said so in the merge discussion. I don't think we'll get away with a WP:PROD. This is the second time a merge has been proposed so no opposition is not guaranteed. SpinningSpark 06:49, 15 May 2022 (UTC)[reply]