Is it normal to suddenly become clueless about your PhD topic and how to rediscover one?

Question

I am working towards a PhD. My supervisor and I decided upon a topic which interested both of us. I did an exhaustive literature survey, and found that there have been heavy work in this area in the past 2-3 years. The problem statement we started with seems to have been primarily solved, and now extensions to those are appearing in top journals and conferences.

Now, he feels that the work remaining in the area is not worth a PhD so we should look for something else, but he still asked me to explore the area. Now, I am clueless what exactly I am supposed to do and where to look for new problems (given that I have already invested my first year into this along with the course work). Is it normal during the PhD that the problem that you expected to have not been mostly worked upon, already has so much work done ?

Now, in this case, how should one proceed to look for new problems or extensions of the problem that are worth a PhD ?

My area is Computer Science.

Answer 1

Don't consider your time reviewing the field necessarily wasted. You say that you've discovered that the research topic that you wished to pursue has already been thoroughly investigated. If this is true, then you are in the happy position of finding this out now before having invested more of your time.

Now, is it indeed true that the topic has been exhausted? Perhaps this is the basis of your supervisor's request that you continue reading around the topic. Is there a line of investigation still remaining that you can work on? Are you sure all the extensions to the primary findings have been looked at? Is there a way of extending into new and unexpected territory?

On this last point, talking to many other people in the field - or closely related fields - might spark off ideas in your head. Discuss with them whether they think all aspects of the topic have been considered. Find people who are not experts in the specific topic, but are conversant with it who might offer a difference perspective. These people might draw you toward research across two fields. Can the results of the research topic you were looking to work on be extended into other, surprising areas?

Answer 2

With the vast output of science it is not surprising that more may be done than what might appear at first. Science is about advancing science and so if your original question has been answered the question becomes what is not answered? A key aspect of all research is that new question spring out of answering (or trying to) question. This leads to the point that one must read up on the literature in the field of interest so that you can identify the new questions that emerge. This is one way of interpreting your advisors suggestion.

It will be very difficult to isolate oneself with a question since others will likely arrive at similar ideas sooner or later. Defining a PhD study can therefore be tricky since it means working on some line of questions for several years. "Knowing your opposition" is therefore a good thing. You need to read up on material not only to identify unsolved questions but also to get a sense of what others are working on. Going to key conferences in your subject is one good way to see what is going on.

At the end, I want to add that I do not think it is your sole responsibility to do all this, after all, your advisor should now more about the field and who is doing what among peers. Getting a PhD is about learning to become an independent researcher and to ask too much of you early on is thus not realistic. What you can do is as stated earlier to read up on literature and build your own picture of the (sub-)field. You will need this knowledge under any circumstance.