QM at the OU: (SM358)

The OU quantum mechanics course I studied back in 2009 was excellent. I spent the first six months (Schrödinger equation, complex vector spaces) as if I were Alice in Wonderland, bemused as to how any of this detailed and comprehensive theory had any connection or purchase on reality.

I spent the final three months realising that I would never know. Because no-one else knew either.

Another QM anecdote. At QM summer school in 2009 (this was a year after the Large Hadron Collider first started up - it was still in testing mode) I asked one of the professors, "Will mastering this course help me understand the physics of the search for the Higgs particle at the LHC?" (it was discovered in 2012).

He scratched his chin thoughtfully for a moment, then gave me his considered answer.

"No.”

I later learned that the prediction of the Higgs comes out of special symmetry considerations of the Lagrangian in Quantum Field Theory. All of this was advanced postgraduate stuff, utterly invisible from the OU course…

And here's Gemini correcting me: https://g.co/gemini/share/983f5af4510e!

Fusion and Fission

Note that 'negative' on the y-axis: this chart is more insightful upside-down

And finally: the difference between fusion and fission. Basically the whole universe - all of the matter in it - wants to be iron. Lighter element nuclei want to quantum-tunnel past the coulomb resistance to aggregate into an iron nucleus; heavier elements (all of which are unstable - mostly with half-lives comparable to the age of the universe) want to fission-decay back to iron, again by quantum-tunnelling through the nuclear force potential.