Instantaneous and Retarded Interactions in Coherent Radiation

Area of Science:

• Plasma Physics
• Beam Physics
• Electromagnetism

Background:

• Coherent radiation in electron ensembles involves stimulated emission.
• The Liénard-Wiechert potential classically describes radiation reaction force.
• Current models face divergences due to instantaneous interaction assumptions.

Purpose of the Study:

• To address divergences in classical radiation theories.
• To propose a new framework for electromagnetic radiation.
• To accurately model coherent synchrotron radiation energy loss.

Main Methods:

• Decomposing electromagnetic interactions into instantaneous and retarded parts.
• Analyzing the contributions of each interaction component to radiation loss.
• Applying the new theory to coherent synchrotron radiation.

Main Results:

• The "acceleration field" in Liénard-Wiechert potential leads to divergences.
• Only the retarded interaction part contributes to irreversible radiation loss.
• The instantaneous part accounts for space charge effects.

Conclusions:

• A novel theory for electromagnetic radiation is proposed.
• This theory resolves issues with instantaneous interaction assumptions.
• The findings offer a new perspective on coherent radiation and collective interactions.