(no subject)

Except, by opening the box, we've collapsed the probability, thus proving that quantum cat exists. But it's still funny. I'm just reading Isaacson's new biography of Einstein right now and I'm swimming in more relativity and quantum mechanics than is good for me.

(no subject)

I'm in desperate need of a mathematical physicist.

As implied in my earlier post, I'm reading Isaacson's biography of Einstein, and I have no problems so far understanding the concepts of Einstein's work. It's really a recap of stuff I studied in college, anyway. However, when it comes to the math, I'm sort of similar to early Einstein in that I never really put much emphasis in math in my academic career. In fact, in four quarters of High School calculus, followed by three semesters of college calculus, my grades were D-D-D-D D-D-C (why did I get a C in college-level Advanced Calculus after four quarters and two semesters of D's? Don't ask, I can only guess myself.)

Anyway, I get the concepts behind his theories. I can grasp space-time, relativity (special and general), E=mc², energy, matter, quantum (pro-dice wielding deity, and con-), Plank's constant, covariance, accelerating elevators vs. gravitational fields, Newtonian swinging buckets of water, the oddities in Mercury's orbit, gravitational lensing, and even his tragic acceptance of a democratic socialist utopia. However, his his tensor equation involving the curvature of space-time:

G_μν = 8 π T_μν

Here's where my math fails me. I understand that the left side involves mass, and is the combination of a bunch of complex multi-dimensional calculus that I will never understand. I understand the right side is the curvature of space-time. I understand because of this the relationship of mass and curvature, how one influences the other and how this cascades into the dance of everything interacting with everything else. I even instinctively grasp how pi must relate to the curvature on the right-side as it's so involved in anything curved through even Euclidean geometry.

But why is that 8 there? We're talking about a 4-dimensional curvature. 8 is 2³ which would imply (maybe) 3-dimensional space. I could understand if that constant were 81 or 16. Or even some irrational number like the constants of pi or e. Or something imaginary like i. Why 8 though? It's so even and round and rational and (to the computer engineer in me) completely ordinary. Why 8?