The first few weeks after enrolling into a PhD programme are the most exciting days. This is actually the stage where all decisions need to be made. Decisions that relate to your supervisor, the project work that you choose etc. one important thing to take care of at this stage is to have a specific and focused topic. This is something I insist upon as choosing a very broad topic can seem to be easy and interesting in the formative stage but as you progress you may fumble with finding relevant material itself because you don’t have a narrow research topic. In addition to that, if your research topic is not specific you would not be able to make noticeable and relevant contribution in your field of study as such a broad topic would get lost in the big broad field of your study.
The possibility of a new discovery or innovative contribution in the existing academia is only workable when there something very specific that you are studying. You can go in the depth of the study then. For a broader and vague topic, you end up floating just on the top as there is so much material in a broader perspective that you feel lost and don’t know what to incorporate and what to leave.
Now, doing so isn't an easy task. Finalizing a topic that is accurately narrow may be very herculean for a novice researcher, more so if he doesn’t have the back up and support of his supervisor in the formative stage. Few are so fortunate to have a supportive and intellectually equipped supervisor. If you are not among the fortunate few, you can still be wary of not choosing the wrong topic initially itself. The best and the most appropriate way to do so is to do extensive literature review reading. The more you will read , the better you will understand the dimensions of your field of study and you will be able to distinguish well between what is specific and what is broad. Make sure what you read is good and worthy literature as one major concern with the overdose of information available on the internet is that researchers get too much and most of it is not good enough to be considered or taken inspiration from.
Try it out and work on your topic, more so if it is your beginning of the PhD journey.