Is Radiation a Frame-Variant Process?

[pythagoras88]

Hi,

Is radiation a frame variant process, which means for example, if someone is co-accelerating with an accelerating charge(such that no relative motion) then he will not witness radiation since to him, since the charge is stationary. However, to an inertial observer outside, he will witness a radiation due to accelerating charge.

If from above example, we conclude that that radiation is frame variant, then it don't sounds right either. Radiation is a physical process, and should not be relative to the observer. For example, the radiation emitted from the accelerating charge progresses outward and result in an energy excitation of a particular atom, then this should be witnessed by all observer and all observer will conclude that there is a radiation.

Is there a problem?

 

[Aaron Barnard]

No, there is no problem. Radiation is not a frame-variant process. The concept of radiation being frame-variant arises because the observer's frame of reference affects the amount of radiation they perceive. For example, an observer moving with the accelerating charge will not witness the same amount of radiation as an observer outside the frame of the accelerating charge. This is because the observer inside the frame experiences a Doppler shift in the radiation they receive, while the observer outside the frame does not. So while the amount of radiation experienced by each observer may be different, the radiation itself is not frame-variant.