Radiation from an Accelerated Charge and the Principle of Equivalence

The connection between an accelerated charge and one at rest in a (weak) gravitational field is discussed in accordance with the principle of equivalence. For that purpose, the fields produced by a freely falling charge and a supported one (i.e., at rest in a gravitational field) are transformed to the rest-frame of the observer, who may be similarly supported or freely falling. A nonvanishing energy flux is found only if the charge is freely falling and the observer supported, or vice versa. This agrees with previously established results.