I am a PhD student in math, for context. I was looking through some old PhD theses from my school, and some of that have to do with finance- specifically financial stochastic calculus. So, when I say "financial calculus" I mean stochastic calculus applied to finance.
Now, I did an internship with Morgan Stanley, and I was working with people who had 7 digit salaries, and they didn't even know how to add fractions. I am not kidding.
They asked for a report on some stock growth and I provided them with a math model and they handed it back to me and said "No, we don't do this here. Just write a paragraph on the pictures."
This got me thinking- how useful is advanced financial mathematics? I doubt anyone in the entire building knew what Brownian motion or a submartingale is. I am not questioning their intelligence by the way- they are extremely smart people. They just don't need or use math.
And I doubt there are people behind the scenes doing some measure-theoretic proofs to help the company. So, is financial calculus at a rigorous level even useful?
If I am being ignorant, please let me know.