 2018

Source paper: www.whatdotheyknow.com/request/oxford_physics_past_papers_2/response/2340696/attach/6/Physics%20Papers%202017.pdf?cookie_passthrough=1

The scanned cover establishes Hilary Term 2018, despite the containing bundle's 2017 filename. Use $\hslash =c=1$, the Minkowski metric signature $(+,-,\dots ,-)$ outside question 2, which uses Euclidean space, and $p\cdot x=E_{\mathbf{p}}t-\mathbf{p}\cdot \mathbf{x}$. The phase and normalization conflicts in question 4 are identified in a; its path integral is evaluated with the normalization of its displayed action.