Different topic creations Many students have in mind something that they want to work on; others want to work with a particular scholar or research centre. In the first case, students search for a compatible supervisor. In the second, for a topic. Regardless of these preliminary circumstances, the topic is very likely only roughly formulated at this stage. This is usually enough to have your enrolment accepted.
Reading the literature Once you have a general idea, you could start by talking to your supervisor and other scholars. But, most importantly, you have to think why you would like to work on it, or why anyone would want to do so. Ask yourself, "Why is it important? What is interesting about this? Suppose I solve it, or find it, or pull it all together, what use is it? What is its significance?" Then, with some questions such as these in mind, go and read more about it to see what is there and find out what aspects of it have been exhausted, what neglected, what the main ideas, issues and controversies are in the area. It is regarded as your supervisor's role to direct you to the most fruitful starting point in reading and surveying the literature.
Cycle of literature review All of this is not a once only activity, but is a cycle you go through again and again. So you read, think, and discuss it with your supervisor and then, as a result, come closer to the formulation of the topic. And then with each cycle of reading, thinking and discussing your topic becomes more specific and focussed.
This is not the final formulation and the last time you will focus your topic. But you could probably let go of this round of general exploration and embark on the next stage. Your supervisor by this time should have enough of an idea of your topic to judge whether or not what you propose to do is feasible within the time available and has the potential to meet the required standards for a PhD.
To see the full potential of your topic or, to the contrary, see that it is not going to deliver what you wanted, you do need to begin doing your research. This, of course, is why pilot studies are often undertaken.
