Forgetting your PhD dissertation

Junaid Mubeen, a mathematician turned educator, bravely writes about how he no longer understands his PhD dissertation, completed just seven years ago:

Earlier this week I read through my PhD dissertation. My research was in an area of Pure Mathematics called Functional Analysis which, in short, meant it was self-motivated and void of tangible real-world application. I submitted the thesis in 2011 and after a successful ‘defense’ made a swift exit from research mathematics.

I was curious to see how much of the dissertation I can still grasp, five years after the fact. I figured it couldn’t hurt my ego if I refreshed my mind with past mathematical glories.

How wrong I was.

This was not the casual read I had in mind. The notation was alien. I even had to scour the examiner’s report to direct me to the key results. And while I could have sworn this was a well-written thesis, I repeatedly found myself bamboozled by my own prompts. “The result now follows easily…” may have made sense back when, but now the author-turned-confused reader can profess that it most certainly does not follow easily, at least in his own mind.

A humbling experience such as this begs the question: what was the point?