Spacetime metric
In special relativity, the spacetime metric, also called the Minkowski metric', is the metric tensor that describes the line element in Minkowski spacetime.
The metric[change]
The metric can be described by the following line element:
<math>ds^2=c^2dt^2-(dx^1)^2-(dx^2)^2-(dx^3)^2</math>
In units where the speed of light, <math>c</math>, is one, then the metric in matrix form is
<math>diag(1,-1,-1,-1)</math>
