How to avoid the "need" to learn more before conducting research?

I sympathise completely with your situation, as I went through exactly that thought process when I began my PhD. I am in my second year.

I did not begin my PhD with a tightly defined research question, and I would guess that you are not doing so either. I did have an idea of what general area of research interested me and spent a lot of time looking at published papers. Sometimes, while reading a paper, I realised that I needed more general understanding of that topic, and then read text books, or attended classes.

I also attended seminars and such like, to get some idea about how other researchers in my general field go about their work. And I volunteered to give talks on quite general subjects in my broad field, on the basis the best way to learn a subject is to try and teach it to somebody else. I have been surprised by how much of that haphazardly gathered learning has turned out to be helpful in my own very specific research - sometimes directly relevant but more often by suggesting ideas to me about a way of looking at a problem.

I thought, and still think, that it would be a mistake to take classes and read textbooks until I was at the frontier of knowledge, because I would never reach the frontier that way.

What I did instead, after reading, more or less deeply, a few hundred papers, was to realise that none of them really addressed a particular question that I was interested in. Having, almost inadvertently, identified a specific research question, I could then conduct a very intense literature review to confirm, or otherwise, that nobody else had researched that question.

Guess what! I had reached the frontier of knowledge. I am now in the process of seeing if I can push the frontier further out.

Unsurprisingly, there is no one-size-fits-all method for balancing the tasks of acquiring knowledge and producing knowledge. It is a very common concern for starting PhD students like you, but in the vast majority of cases things work out fine. I'll try to explain why and how:

Acquiring and producing knowledge are not mutually incompatible tasks. In fact, they are often fruitfully combined with each other. For example, one may read a paper which gives them an idea for a new approach in their work; conversely, one may stumble upon a problem in their research and switch to discovering how existing works deal with the same kind of problem. The balance is achieved by keeping a flexible goal-oriented approach, by this I mean that it combines two aspects:

• Nobody can know everything in their field, so researchers don't try to achieve that. Instead they focus on the topics which are susceptible of contributing to their own research. That's the in-depth aspect of acquiring new knowledge: choosing what one needs to know in order to progress in their own research goals and study every detail of it.
• On the other hand, researchers need to keep up to date with the major discoveries in their field. But for that they don't need to know or even understand every detail of every single new paper, they can skim through abstracts/papers and select whether they want to dive deeper depending on their goals (or depending on how soon their next deadline is). That's the in-breadth aspect.

Naturally figuring out one's methodology, for example recognizing the papers of interest, takes some learning. Well, that's exactly what a PhD is for: a PhD student is a researcher in training. It's understood that they are not immediately operational and that they need to acquire a lot of new knowledge, both in their specialized field and in general scientific methodology.

It's very common to spend at least the first year (often more!) of PhD learning and exploring around the research question, sometimes a bit randomly. During this time it's frequent not to actually produce anything, and even occasionally spending time exploring something which turns out to be irrelevant. It's fine, mistakes are entirely part of the research process.

What is important is to keep a main research objective in mind: at the beginning it's often a very general and vague objective. Then progressively, by getting a better understanding of the state of the art and discussing with your advisor, you will start zeroing on what will become your specific research contribution.

I'd rather like to give you some practical tips. In my view a big part of a PhD is learning how to learn and to deal with the huge information overload that might exist in your field of research, especially nowadays. Reading a 100 papers is warning signal in my opinion. Most PhD thesis only contain 100-200 references. Overflying a 100 is ok. This points me to the suspicion you are analyzing and reading the literatur not efficiently and this is of course a matter of time.

So, if I would start doing a PhD again, I would like someone to tell me how to select and what to read. My suggestions now after PhD are:

• Start with a review article published in the past 10 years instead of reading the most cited current papers, which will not help a lot, as those are very specialized research reports, often in letter format.

• If you don't understand most of the content, read a text book covering the topic, if you still don't understand you have to switch to university courses, lectures, seminars

• after reaching some understanding look for open questions -> search google scholar with

  "intitle:opportunities/advances/roadmap" AND "your field"

as these articles look into future, list open questions or methodological gaps. Simultaneously you should visit conferences, workshops and summer schools if you can and talk especially with PhD students which are at the end of their odyssey and discuss open questions.

• then you have to decide what you can and would like to do, where sits the expertise of your advisor, your colleagues and you and what facilities do you have (intellectual, experimental, computational ... you have at all). This will narrow down a lot what you actually can do and running into too many dead ends, which you have to risk in fundamental research.

The rest is the PhD. And when you are able to come up with new correct and interesting questions to your peers in your field your supervisor could not think of, this is a very good sign you have become an independent researcher, which is the main goal of a PhD.