I am doing my second postdoc under someone who is well known in the field. I did some extensive calculations and got very good results in my grad school on a topic out of curiosity. My PhD advisor was okay with it but never wanted to publish a paper out of those results as they were not his expertise.
Now when I was in my first postdoc position I had written up the entire work and asked my PhD advisor whether I should put him as a co-author. He declined to be a part of it and advised me to publish it on my own. In the meantime I moved to another position and now my advisor is a big name in my field.
I am currently in a big dilemma. Do I need his permission to publish it as a single author (as I have use the institution's affiliation) or should I just go ahead and submit it? Because my fear is that if I let him know about this paper he will certainly slow it down by being a part of it and as a postdoc I need more publications. He is not in a mood to help me out with more publications while I have already given him tons of good results. Please help!