Please see the subpages and any attachment. Please use the attachments at your own risk.
I have produced original materials on various mathematical topics that may be relevant to "Mathematical and Theoretical Physics".
You might be amused by the "4 Equations in 4 Unknowns" material that I produced.
See the sub-page
Solving Small Systems Of Linear Equations
I always wanted to work this through, "not very clever of me to actually do it".
Also I was "always" interested in deriving the form of the rotation matrix. As a chemist with limited experience of using the required math (and I suppose with other things to do) it didn't happen but now it has. See the sub-page
"Unfortunately" I have been side tracked from some 'Tensor Analysis' I had in mind. I intended just to look at how to produce diagrams programmatically, for this work but one thing led to another and when I re-focussed on the physics and math I ended up interested in 'Quantum Optics'.
Best Wishes,
Roger