Consider the following metric:
ds2=h(r)(dr2+r2(dθ2+sin2θ dϕ2+(dψ+cosθ dϕ)2))
We can try to compute the Ricci scalar of this metric by using Mathematica packages like RGTC but the result is horrendous. Instead we could introduce the following one forms:
eθ=r dθeϕ=rsinθ dϕeψ=r dψ+rcosθ dϕ.
Using these forms the metric now looks diagonal
ds2=h(r)(dr2+eθ⊗eθ+eϕ⊗eϕ+ eψ⊗eψ)
However I cannot plug this metric as it is into Mathematica. It will give wrong results. My question is: Are there Mathematica packages online that compute Einstein tensor using the vielbeins in which the metric is diagonal?
This post imported from StackExchange Mathematica at 2014-11-29 15:08 (UTC), posted by SE-user Orbifold