I don't know how to approach the following problem: I've been out of the research world for several years now, and I'm currently working in a different field. I've completed a scientific work as an independent research that I would like to publish (in theoretical physics - foundations of quantum mechanics), but unfortunately, I don't currently have an academic affiliation. This certainly makes it more difficult to publish my article, as well as forcing me to pay for publication myself (although that wouldn't be the worst problem). As far as I know, it's difficult to publish a preprint even on arXiv without an academic affiliation.
Is there a form of voluntary academic collaboration (i.e., unpaid) that would allow me to have an affiliation and possibly interact with other researchers? I live in Italy and the people with whom I graduated and did my PhD currently work on topics quite different from the subject of the work I would like to publish. Moreover, I've completely lost contact with them.