You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
Wait is L the derivative of R(θ) at θ=0 or is it -i times the derivative of R(θ) at θ=0? I think there’s a conflict between what you typed above and what’s in the picture...
It’s -i Times the derivative.. of you look closely since I raised e to +I they cancel out. You could argue that this is pointless, but the reason for that is so that L is hermitian as opposed to antihermitian.. this is a matter of convention
Consider the 2D rotation matrix R(θ)
The Inverse of 𝑅(θ) is just "undoing" the rotation by θ
Note that the last property 𝑅ⁿ(θ) = 𝑅(𝑛θ) is eerily similar to the "de Moivre property" .
