I have a big problem with my research. I calculated the variational of a curvature functional by hand (deltaVcurv), andI am trying to compute the Euler-Lagrange equations of a functional with Mathematica and then the vector aeom. When I try to subtract these results, it takes days and days running and nothing happens. I am trying to verified that my calculation by hand is right so I need a zero in the final answer.
What can I do? Am I doing something wrong? Why do you think it take so much time?
Well, one thing to recognize is that your expression check3 has ten million leafs.... it is a phenomenally large and complex expression.
Perhaps the best approach is to take the steps in Mathematica that you took "by hand" and verify your expressions along the way.