I'd be thankful for any idea thrown my way (be it actual companies, domains or just vague career plans).
Cheers
I'd argue that you can distinguish between career paths that
- make use of and are related to your broader specialisation within maths (e.g. fluid dynamics, actuarial sciences, cryptography, derivative pricing, specialised ML research...). For these, it's hard to give recommendations without addition details. They can still be open to folks from unrelated maths backgrounds, but it depends on other experience and circumstances.
- are highly quantitative and tend to value PhDs from quantitative disciplines (e.g. "Data Science" & data consulting companies, banks, (Re)insurance companies with internal training, quant trading, applied ML research and startups, possibly sports betting...). For these, PhDs in physics and EEE will probably be similarly appropriate.
- value smart people with academic titles regardless of discipline and might require separate skills and qualifications (e.g. strategy consulting, IT consulting, patent attorney, software development ...? ).
I would start by assessing where your interests and qualifications sit within that range. It can help to start by focusing on a specific industry that you find interesting and then find out what kind of maths-adjacent roles there are. In my experience, this tends to be very different for purer vs more applied maths PhDs.
[1]: https://rocmdocs.amd.com/en/latest/ROCm_Libraries/ROCm_Libra...
Members from my class (including +/- a couple of years) went to startups, think tanks, SEC, NSA, trading, hedge funds, digital media, academia, postdocs, consulting, and commercial research labs that are incubators within larger corporations.
You didn't indicate your specialty, but it probably does not matter. Many current DS and related jobs list PhD in a STEM field as baseline or preferred requirement. I know logicians who got non-academic work (this is not a dig at logic, they were really worried about this).
If you want to go the software developer route, at this point you do know how to study for leetcode type puzzles. But you are in direct competition with many others who specialize in that, and a PhD in math will not carry much extra weight in the hiring decision.
Watching my own and my peers careers evolve over time, the impact of one's network should not be underestimated.
Finally, assume you will never be asked about your dissertation. Ever.
Consulting for oil/gas/drilling as they always need analysis.
Financials.
Data analytics (of any kind).
Physics labs/research labs.
Manufacturing (optimization problems, efficiency problems, actual problems Have you thought completely outside the enclosure? Sitcoms (look at the people on Futurama or Big Bang for example) Porn (how _would_ you figure out the volume of that thing??) Entertainment (Bill Nye the science guy, rosetremiere the math is near!)
Since I don't want to tamper my anonymity here, let me tell you a few tips:
First, find out for yourself whether you want to work in enterprises or startups. Whether you want to apply scientific methods/conduct private research or not.
I had a clear idea for myself: startup+research. Once you know this, you can basically let yourself "go with the flow": Look up interesting people and topics (at TED(x) conferences, at youtube, at fairs or conferences) and ask if you can work with them. Works best if they are CTO/CSO at their startup (such as I am) :-)
The short story is: software development. Sure, there are more quantitative jobs like data science and ML and other mysterious math/scientist jobs that are quite hard to find and secure, but software development of any kind is the quickest way to a job. You'll need to convince people you're not a pie in the sky thinker, and so I'd recommend building up some side projects. Functional programming languages will probably suit you better, and those jobs can sometimes be more technical. Also, universities and research institutions, at least in the U.S., are hiring more and more software developers.
Regarding trading and blockchain, having some principles is fine, but you also need to eat. There's nothing wrong with taking a job for a couple of years to get your feet into industry and then moving on from there.
I would pick AI, because it's a growth industry with on-going innovation. You would also be able to work in many different kinds of applications. It seems like it would be fulfilling work.
You didn't mention why you're uncomfortable with trading. Finance used to be a great choice, but it's not a growth industry now, innovation stopped after the Financial Crisis in 2008, and the industry has been saturated with PhDs for over a decade. Meaning math PhDs not in demand very much anymore in finance and most of the work is not very interesting anyway.
Personally, I wouldn't pick crypto ("blockchain") as a lifetime career.
Note that any of these career would require significant effort and learning on your part. You didn't mention what your PhD in mathematics is in. You would be competing with PhDs who have done their thesis in something highly relevant to AI or finance and/or have done a great deal of research on the topic before applying for jobs in their target field.
If you don't care about how much money you'll make, and enjoyed your PhD work, then I suppose postdoc would make sense. If you don't care about money and didn't like the academic environment, then you could go into teaching relatively easily with your qualifications. Perhaps teaching / lecturing at a private school or college, if not a university. I would suggest that you do care about money though, because it is an important factor in determining your quality of life.
Any kind of data science/machine learning?
Disclosure: I work for one of those firms (CipherTrace) so I may have some bias, but really, this is the portion of the Fintech/Crypto spectrum I find acceptable.