I am a PhD student collaborating with another PhD student A, under supervision of Prof. B & Prof. C. I am student of Prof. B. Student A is co-advised by Prof. B and Prof. C.
Prof. B chairs the project. I was asked to join this side-project because of my certain experience.
Our work requires knowledge from both A and me. A is doing well in his part. However, the novelty in my part, is problematic (in my view) and hard to produce. To this, not everyone is convinced: Student A thinks I need more tunings; Prof. B is dubious yet believes the novelty; Prof. C agrees with me but with a little suspicion.
I have now enough lab evidence to support my claims (i.e. the failure novelty). And I believe I will convince others at next meeting.
I would like to quit this project, and do not want to waste more time. Student A can still publish his part, just not a "big" paper though. And I will not ask for any credits of course.
How can I, with enough respects, yet properly quit the project without hurting feelings of other colleagues? Especially student A and Prof. B?