Homework Statement
Say we have two manifolds N(dim d) and M(dim d-1). Let Φ: M →N be a diffeomorphism where Σ = Φ[M] is hypersurface in N. Let n be unit normal field (say timelike) on Σ and ⊥ projector (in N) defined by:
⊥^a_b = \delta^a_b + n^a n_b
Where acting on (s, 0) tensor projection...
I'm trying to do past exam papers in GR but there are some things I don't yet feel comfortable with, so even though I can do some parts of the question I would be very happy if you could check my solution. Thank you!
1. Homework Statement
Spacetime is stationary := there exists a coord chart...