The thing about quantum gravity is, it's going to be massively heavily mathematical. You will be doing tons of metrics and integrals and maybe some topology and many other related things.
Most undergrad physics degrees include some calculus and algebra, but usually only up to 3-D integrals and...
You asked for advice on studying. Didn't see anybody give a lot of advice on that.
Overall strategy: You are in a degree program. Figure out where spending your time will give you the most benefit. If you need this class, you should be spending a lot of time on it.
Be sure to read your text...
Just to make sure I understand, your integral is the following, right?
$$ \int \frac{1}{ \sqrt{.443s^3+1}} ds $$
The gnarly thing here is that it is ##s^3##.
So, are you stuck on doing the integral? Or on getting it into Excel?
These days, an engineer would probably use some sort of computer aided design (CAD) program. There are a number of them. They do a variety of calculations on demand.
Such software is typically fairly expensive. The more features and the smaller the industry, the more expensive it is likely to...
The Lagrangian comes from a few places.
One is, you take a classical field that has a Lagrangian, and write the corresponding equivalent for quantum field theory. That only takes you so far, since there isn't really a good classical field theory for electrons. You can get the E&M part of QED...
Sorry to do the old post thing. Maybe it helps somebody else.
I experienced similar things on a UNIX system running MCNP using MPI. The problem turned out to be because MCNP is not very clever about reserving the resources it needs. Memory and connections between nodes and such. So, if some...
I noted that your starting keff is quite high. A value of keff=1.118 is going to be in the prompt range. It's not clear that MCNP gives you sensible results in that range. Even the 1.025 is kind of high. Is it still prompt? I would need to do some careful examination. Don't have MCNP available...
Astronuc did answer your question, but here is a restatement of the problem in simpler terms.
Putting stuff in the plasma will have a strong tendency to mess up the fusion process. You want only the things that are reacting, especially you want as little as possible of isotopes with higher...