Note: The angular frequency ω can be assumed to be positive. This is because cosine is an even function, so in terms of E‘s motion a sign change of ω has the same effect as a sign change of both α and β.
Note: The angular frequency ω can be assumed to be positive. This is because cosine is an even function, so in terms of E‘s motion a sign change of ω has the same effect as a sign change of both α and β.