I'm a PhD student and I'm getting started in the field I want to work on after I finish my PhD. There were some very important works done by a very experienced researcher and collaborators that I've been trying to understand for a while. In fact there was claim in the beginning of one of the papers that was central to all that followed but I wasn't able to understand why such a claim is true.
Some weeks ago that experienced researcher gave a talk on the subject and he stated the same claim that's on the papers. Still, I didn't have the courage to ask about it because I really don't know yet whether it is something extremely basic that I'm missing or if it's really non-trivial.
I was thinking about sending an e-mail asking about it. But can that damage my reputation? I mean, if it is something really basic and obvious, and I'm missing it, won't it damage my reputation with him if I ask it? The reason I'm worried is that I really hope to be able to collaborate with him one day.