Can anybody tell me what is Causal Solution

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Causal solutions refer to solutions in physics where events are influenced only by prior occurrences, ensuring that no future events can affect the past. This concept is crucial in understanding wave equations, particularly in the context of field radiation, where retarded potentials serve as causal solutions. The discussion highlights that the term "causal" emphasizes the importance of time and the finite speed of light in the propagation of disturbances. Additionally, participants clarify that the causal structure is mathematically represented by the light cone. The inquiry about the term's meaning is resolved, confirming its significance in both physics and general language.
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Can anybody tell me what is " Causal Solution"

hi, everybody:
I am now reading some thing about field radiation. and it claims that the retarded potentials are the Causal solutions to the wave equations? http://www.ece.rutgers.edu/~orfanidi/ewa/ch13.pdf"

Can anybody explain what is the Causal solutions?
 
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your notes seem to have explained it pretty well... what is problem? "causal" means that events do not happen before the "trigger" that initiate the events. THat's why it the time argument, you need to evaluate the quantity at an eariler time.. because speed of light is not infinite, and it takes time for disturbances to reach the point of interest away from the source.
 
mjsd said:
your notes seem to have explained it pretty well... what is problem? "causal" means that events do not happen before the "trigger" that initiate the events.

I am sorry English is not my native language, but is the "Causal" has such kind meaning? Can you tell me an online English dictionary to check that?
 
In physics 'causal' can mean just that the future cannot affect the past. In other words an event may only be influenced by earlier events - not later events. Mathematically this give us the light cone causal structure.
 
Thanks Mentz114, I got the answer I want!
 
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