Professor wants to submit paper, but no real results
You have two options. First option: decline to be the author of the paper, second option: write and submit the paper as first author. In the second case, the paper will go under review and the reviewers and the editors will decide if it is a good publishable result. Personally I would choose the second option in a high-medium ranking journal. In this way, if the paper will be rejected, it will not be your fault and you will not enter in contrast with your professor.