9815
The speed of light in the medium is given by In vacuum , ε0 = 8.85 × 10 − 12 C2 · N − 1 · m − 2 and μ0 = 4π × 10 − 7 H · m − 1One possible way to obtain the required matrix representation is to use the Riemann-Silberstein vector given by If for a certain medium ε = ε ( r , t ) and μ = μ ( r , t ) are constants ( or can be treated as local constants under certain approximations ) , then the vectors F ± ( r , t ) satisfy Thus by using the Riemann-Silberstein vector , it is possible to reexpress the Maxwell 's equations for a medium with constant ε = ε ( r , t ) and μ = μ ( r , t ) as a pair of equations .
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