<p>I did a BS and MS in Comp.Sci. I want to do research in theoretical computer science and I'm wondering should I continue to pursue a Ph.D in Math or a Ph.D in Computer Science.</p>
<p>What is the difference if I took Math instead of CS, in terms of future R&D in universities or research laboratories?</p>
<p>Thank You!!!</p>
<p>what type of math and what math courses have you taken?</p>
<p>If you want to do theoretical CS, get a PhD in CS.</p>
<p>There’s WAY more funding for computer science than math. Heck, when I was an undergraduate, I had (CS) professors encourage me to get a PhD in theoretical computer science instead of math because it would make me more employable and still allow me to work on many of the same questions that a mathematician might work on.</p>
<p>Well, you can still go into cs from math. Many famous computer scientists, such as Seymour Papert, Marvin Minsky, John McCarthy, Donald Kunth, Hal Abelson, Gerald Jay Sussman, all have their PhDs in math. </p>
<p>I even had a professor who, although he was apart of the math department, occasionally taught cs courses, such as intro to java, and theory of computation/automata. </p>
<p>Though, I don’t think its as common to go into math with a degree in cs.</p>
<p>Unless your PhD is Math leans more towards computational mathematics, parallel algorithms, discrete mathematics or cryptology, I would NOT go for a PhD in Math if you plan to go into CS.</p>
<p>The OP says he’s interested in doing theory, which basically includes all the fields you listed, and many more. So it would not be weird at all for him to go into an applied math program. The question is just whether it’s beneficial to do so.</p>