I was wondering how many concurrent research projects a typical math researcher works on at a given time. I ask because I currently have the oppertunity to start a second project on something I'm fairly familiar with (background reading-wise). One of the main reasons I'm considering taking in a second project is because the first one is going rather slowly (I've hit a roadblock which is potentially insurmountable). In general, is it a bad idea to be working If you do work on multiple projects, do you tend to jump between them the moment you get stuck or do you dedicate your full attention to one of them, for say, a week? What's your secret to staying productive?
Just to be specific, let's limit "projects" to writing (contributing to) papers you intend to publish in the near future. As well, "working on" should be interpreted as dedicating a sizable chunk of your time to researching the problem at hand. I do not wish to count projects that you put aside for more than a few weeks until you have an inspiration.
I understand the question is somewhat subjective and the obvious answer is that it depends on the person in question. The way I see it is when you work on multiple problems, part of the reason is that you are hedging your bets on which problem will end up solved. However, I'm just interested in the overall average (which im guessing has little variance) and more importantly whether it's bigger than 1.
