I find this subject interesting

https://arxiv.org/pdf/2203.10602.pdf

Yet, I can't understand anything because the concepts and methods used are alien to me and I don't even know what kind of background I have to develop to start understanding these things.

Do anybody here has any recommendations about what I have to study to understand the paper? Because it can't just be "mathematics" or "formal logic" but clearly something more specific in those fields.