When it comes to deciding on a topic, the process usually will differ for each author as per the interest, experience, and the ability to contact resources. That said; some common guiding ideas exist to help you select the most convenient topic.
First, find out your areas of interest. It is understood that over the academic years, you must have come across some interesting topics that you would like to go deep into for more information. Just recall and you are likely to find some exciting topics. However, if you have more than a few topics, it is time to find out which one attracts you the most.
Second, if you really do not know from where to start and how to go about, you can look for advertised PhD positions online. This is where key research grants fund PhD scholarships as a part of research initiative. The PHD projects available here are designed by the experienced researchers who have grabbed the grant. If you are certainly striving hard to find out your own research topic, it might be useful hunting the net for existing projects. However, there are trade-offs. For example, you perhaps will not get much chance to change the scope of your research.
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