Tl;dr: Defended my Ph.D. two weeks ago. However, right from the time of the defense and up until the present moment, I am experiencing a huge lack of motivation and sense of purpose to do anything related to research or search for future positions. How to address this?

Other details: I had applied for other positions before my defense and was not successful in securing a suitable position. I have an offer from my Ph.D. advisor about a postdoc position which I am expected to start early next year. Ideally, a postdoc at some other place would have helped my CV more. Though I will be doing a new project with a new modeling technique, I have been told that pursuing postdoc under the Ph.D. advisor is frowned upon in academia.

Leaving every other concern aside, I am very appalled by my lack of motivation and the constant feeling of lethargy to start with the pending research work and/or resume with the dedicated job search.

I have no idea how to address this feeling. I have taken two hiking trips during the last two weekends. However, it feels empty and unproductive inside. I have so much to do before I start with a postdoc position. But all am I doing is wasting time. I am feeling so incompetent inside.

Are you sure you even want an academic career? To be honest it sounds like you don't.

By the way I would ignore the nonsense about doing a postdoc under your PhD supervisor being frowned on. Too many people are prepared to spread absolute horse manure without thinking it through. It's not 1950 any more. Do a postdoc with whoever you want, Follow where the research that you want to do leads you.

You could just be exhausted/drained from it all. How about a vacation and more hiking!?

I totally agree with pm133, I'd ignore nonsense such as it being frowned upon to do a post-doc with your PhD supervisor. Of course, it could be good to experience working with another in a different institute, but also that could not go to plan. If you work well with your supervisor then continue. it looks promising that you will be working on a different project.

I would spend the first part of any vacation totally switched off, and then when you feel ready, start to think a bit about your options in academia or elsewhere.

All the best,
J

I failed to secure a postdoc before my PhD defence but I did manage to get 3x interviews. Perhaps get someone such as a supervisor to check one cover letter and CV to better understand what they are looking for. If possible get a mock interview with your supervisors. Getting academic positions is tough, after recently passing my viva I also feel so unmotivated and I am doubting my ability to do a postdoc. I spoke to my phd supervisor and she said academia is tough you apply for 12 jobs get 4 interviews you are doing good especially straight out your PhD. I am yet to gTake a break reenergise and I bet your motivation will come back.

Working for your PhD supervisor is not frowned upon, most of my cohort are doing postdocs for 1 year with their PhD supervisors.

I remember experiencing these feelings that you are having. I took a break after I graduated with my PhD and thought I will be able to jump into a position when I felt good and ready. But when I did try and the job responses weren't coming in and I saw my former school as my only option for working, in I started feeling very similar to how you are. But as someone mentioned above, if you want to work in your former lab, that should be fine. However, hopefully you are still interested in the work being done in the lab and you feel that you can thrive in that environment still. If not, then this may bring on more wavering emotions throughout your post grad time there. If you want to go into industry I say stick with applying to jobs there. Eventually you may land a position you want. It took me a long time to land my industry position as a Field Application Scientist but it was well worth my uneasy wait. Keep the Faith. Accept the position you are in and the emotions experienced. Find Motivating things to listen to or read to keep you going. And go after what is more likely to make your heart Happy.

I understand that feeling. I've been there before. Perhaps you want to look inwards and check if there are any stressors wearing you down emotionally. For me it was largely lethargy and depression arising from a bad supervisor and later when my dad passed. I learnt to deal with my supervisor and mourned my dad though the pain sometimes still surfaces.

After my viva voce, I took a one-year break (I called it a mental break) during which I reconnected with myself, grew close to family, volunteered, gained more self confidence, published my remaining manuscripts and did a lot of public engagement in my church while also applying for jobs and deciding what I wanted.

The break was tough financially as no money was coming in but it was absolutely healthy and necessary for my sanity. I would have loved to start work elsewhere but my applications didn't scale through. Now I am back at my university as a lecturer, a year and five months after my defense. I feel much more energetic and ready to conquer the world. My plan is to run my own race, not compete with anyone, try not to let the work load stress me and hopefully impact lives positively through teaching and research.

So I'll advice you to take the postdoc opportunity and ignore the negative voices. Also explore the idea of an extended break to rejuvenate yourself and think about what you really want to do. Stay positive. A day at a time. You'll be fine. Best wishes.