What is a linear medium?
What are your thoughts? What is the general definition of linearity? What kinds of media would you think would be non-linear for some types of energy propagation?
Definition-wise, does it mean that different waves at any particular point in the medium can be superposed? Normal optical glass ie BK7.
The general definition of linearity is here:
It basically tells you how the output of a system behaves with different inputs. In many systems, being able to assume linearity simplifies the analysis significantly.
What physical systems are you interested in? Optical systems, electronic systems, physical systems, etc?
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