Undergrad Does Poynting's Theorem only involve external fields?

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Poynting's Theorem describes the energy transfer rate in a region, incorporating both the work done on a charge distribution and the energy flux. The theorem's equations indicate that the electromagnetic fields, represented by the electric field (E) and magnetic field (B), include contributions from both the charge distribution itself and external sources. This means that the fields are not limited to external influences alone. However, the discussion highlights that point charges can introduce mathematical complexities in this context. Overall, the theorem encompasses all sources of electromagnetic fields.
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Poynting's Theorem (https://en.wikipedia.org/wiki/Poynting's_theorem) says:

The rate of energy transfer (per unit volume) from a region of space equals the rate of work done on a charge distribution plus the energy flux leaving that region.
$$-\frac{\partial u}{\partial t}=\mathbf{J}\cdot\mathbf{E}+\nabla\cdot\mathbf{S}$$
Poynting's vector is given by
$$\mathbf{S} = \frac{1}{\mu_0} \mathbf{E} \times \mathbf{B}$$
Field energy density is given by
$$u = \frac{1}{2}\left(\epsilon_0 \mathbf{E}\cdot\mathbf{E} + \frac{1}{\mu_0}\mathbf{B}\cdot\mathbf{B}\right)$$
Does the EM field ##\mathbf{E}##,##\mathbf{B}## include the field from the charge distribution itself or is it only the external field due to external sources?
 
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It is the field from all sources.

Note that point charges cause mathematical problems here.
 
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