I am 2nd yr PhD student in Theoretical Computer Science. After first year I have lost my interest on my research. Every day I am feeling nevus and tension to do my work. But many people back at my home have kept lot of hopes on me that I will finish my PhD. I don't know how to express my feelings to them. Right now I have a job in my hand which also pays me twice as much fellowship which I am getting now. kindly give me your suggestions to me. Thank you.

I think at some point every academic loses their appetite for their PhD research, and is to be expected. You are closing on your final year (ideally), and logic would suggest you stay the course.

However have you lost interest in the field in general?
Do you want to be an academic at the end of the day or apply your technical expertise in the industry? What is your end game?
The guys who currently have your dream job, what do their CV's look like?

Look at the long game. Rely more on your vision (the future) than your sight (current job). Economies shift, industries collapse and rebuild, and companies restructure. Your job might be great now, but tomorrow is not given. If however, you don't need a PhD to get to the next level in your vision, and you are doing it more for your hometown than yourself, then you have to make that final decision.

I don't know why you've lost interest in your field but my advice to you is NEVER feel compelled to do something because of what others may think- don't stay because your family expects you to finish the PhD. This is about you not anyone else so make your own decision and forget about what others think.

I think you've already been given some good advice, but here is my opinion.

Ask yourself whether you would want to continue if there was no one else in the equation (meaning no expectations of friends and family). If the answer is a firm and absolute no, I'd say go to your supervisor or graduate studies officer and discuss possible exiting strategies. You have worked for too long (and presumably too hard) to walk away with nothing for your efforts. You should explore possibilities of writing up what you do have presently and making it an Mphil. I would also ask your supervisor realistically how much more needs to be done to get it to PhD level. If it is a matter of just one academic year I personally think you should push forward and get the damn thing in. If it is longer than 12 months I can understand not wanting to commit yourself to something you do not want in the long term. In the end all that matters is you are doing this for you, no one else.

I think you need some real thinking time, write down what your long term career plans and goals are. You need to focus on what YOU want, not what others expect out of this process. Whatever decision you come to will be the best for you, and sometimes it takes a braver person to walk away from something that just isn't right.

Good luck, let us know how it goes :)