Revisiting Radiation Reaction: A Delayed-Interaction Perspective

Radiation reaction remains one of the unresolved questions in classical electrodynamics. This challenge mainly stems from unphysical features in the Lorentz–Abraham–Dirac (LAD) equation, such as runaway solutions and pre-acceleration. In this work, we revisit the problem by accounting for electromagnetic interactions with finite propagation delay [1-3]. We show that LAD terms naturally appear as the primary contributions in a convergent expansion, differing only by factors. This suggests that radiation reaction results from delayed interactions rather than an instantaneous force. The model also includes dipole and dipole-dipole interactions, offering a causal and physically intuitive framework for charge dynamics. Methodologically, we treat the delay due to finite signal propagation as a random variable with a uniform angular distribution, providing a first-order approximation [4-5].

 

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