Talk:Inhomogeneous electromagnetic wave equation

Latest comment: 9 years ago by Maschen in topic Mixture of units

Retarded solutions? I have a funny feeling that that was vandalism. I'm taking it out.- 66.75.113.137 03:32, 7 May 2006 (UTC)Reply

Actually retard is the actual term, and is not vandalism. It's not retard in the noun/stupid sense, but retard in the verb/delayed/slowed sense. Basically, a retarded potential is one where the potential measured is the result of the postion of charges and currents at some previous time (called the retarded time). It's basically a reflection of the finite speed of light/electromagnetic-force. If you start a current going at time zero, it's effects won't be felt until time d/c, where d is the distance from the measurement from the source and c is the speed of light. But by this time, the current may have changed or moved, so to calculate the force at a distance d from the source, you pretend that it's actually time zero (that is the current time [d/c] minus the time it would take for light to cross the distance [d/c]). The definition of retarded time is t_retareded = t - d/c, where t is the actual time. I hope that clears that up. DAG 17:17, 31 July 2006 (UTC)Reply

Is NONhomogeneous the right expression? I thought it is INhomogeneous. Just a question/suggestion.

I'm not sure that I've seen non-homogenous wave equations, so as far as I know in-homogenous is the correct term. DAG 17:17, 31 July 2006 (UTC)Reply

Why are the pictures of the CFL lamp and cosmic background radiation on this page? They are not cited anywhere.

Extra curvature term in the co-variant formulation in curved spacetime? My understanding was that this was forbidden by the Strong Equivalence Principle.2.125.15.72 (talk) 19:10, 16 May 2011 (UTC)Reply

Traveling from the future to the present

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Is there a better way of describing that? Sounds like you are saying something is traveling backwards in time. Daniel.Cardenas (talk) 13:08, 14 September 2008 (UTC)Reply

Mixture of units

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In this edit I removed the Lorentz–Heaviside units since most of the equations are given in SI or cgs units. The LH units can be reinstated later. Currently the article now has a mixture of SI and cgs, I'll make the overall presentation more consistent later, but its not bad as is for now. M∧Ŝc2ħεИτlk 17:22, 20 January 2015 (UTC)Reply