consider the space-time transformation of translation
xμ → x'μ = xμ + aμ
where xμ is a point in space-time and aμis a constant 4-vector. Assuming translations are generated by the operator U=e-iPμaμ acting on fields Φ(x), derive the representation of Pμ on the field Φ(x).
The Attempt at a Solution
From looking at it I would assume it would look something like i∂μΦ
Though if this is the case I'm not entirely sure why.