Definitions

In this thesis we try to use the following definitions consequently. As you all know minus signs and factors $2$ can really spoil your day.

• Where no summation symbol is explicitly stated, summation over repeated indices is implied.
• metric: $\eta = diag(1,-1,-1)$
• Greek indices are space-time indices
• Small Roman indices denote space components
• We will use units where $c=\hbar=e=1$.

In this thesis I often say 'Lagrangian' when I actually mean 'Lagrangian density', this is also very common in the literature so I hope you will forgive me.