Not All Combinations Make Sense
10/15/2

Lately I�ve been having black beans and tuna for lunch, or some combination thereof. Today, it�s jalapeno black eyed peas and tuna.

TC has great candy in his candy bowl in his office. I only eat the Warheads and the Double Bubble though. I had two pieces of gum in while I was making my lunch. One was Apple and the other normal.

The black eyed peas smelled wonderful microwaving. With 26 seconds left, I went back to my office and got a fork. I had already opened my can of Bumblebee Tuna and had it waiting in the lab, already drained.

I drained the hot black eyed peas with the plastic fork and then used it to get all the tuna out of the can that I could. At $1.39 per can for the good stuff, I scrape the can.

The fork had a little tuna on it, so I ate it off.

Gum + Tuna = NOOOOOOOOO!

Yeah, I like gum. Yeah, I like Tuna. But I don�t like Tuna Gum.

My NASA Contact wrote the following in an email. I'm so glad I didn't go for a masters:

This morning I had my second test in Math Methods. I feeling the same way I felt after the first test. I think I passed, but I'm not sure I'll get an A. Last time I did get an A, but I'm not holding my breath this time.

The first question involved determining the metric tensor for circular cylindrical coordinates, expressing that tensor as a 3x3 matrix, calculating the determinant and inverse of the matrix, calculating the three non-vanishing Christoffel symbols of the second kind, and expressing the covariant derivative in terms of covariant components. That problem took me well over thirty minutes.

The second question was to determine the adjoint (transpose of the complex conjugate) and inverse of a matrix. It was only 3x3, but four of the elements were imaginary. We also had to prove that the products of orthogonal matrices are orthogonal, and that the inverse of a unitary matrix is unitary. That took me another thirty minutes.

The third problem was the worst, because it only took me fifteen minutes, which has me worried that I did it wrong! We had to prove that the metric tensor is a second-rank covariant tensor. I really didn't know how to do that. I thought it was second rank and covariant by definition! Then we had to show that the dot product of covariant basis vectors is the metric tensor, the dot product of contravariant basis vectors is the inverse metric tensor, and the dot product of a contravariant basis vector with a covariant basis vector is the Kroneckar delta. Those only took me a few lines each. They seemed too easy.