Publishing a physics paper when you are outside academia?

Question

I'd like to publish a paper in a cosmology journal. However, I've been outside academia for about 3 years since completing my masters. Is there any platform where I can share my idea and get feedback to beat it into shape? Or where it can be critically judged? What is the best way to proceed to get this published?

Answer 1

To answer your question: yes of course it's possible to publish a paper if you are outside of academia. However I would like to make the following important comments.

1. Even if you'd like to publish a paper, there is no guarantee that your work will meet the quality threshold of any one journal. It's not a matter of "liking" to publish stuff (everyone would like to publish a paper), it's mostly a matter of meeting the quality requirements, and meeting these requirements has (in principle at least) nothing to do with holding an academic position.
2. It is often easier to meet the quality requirement if you are part of an active research program, simply because you are more likely to be current with the topical literature and have better context to judge if your work is actually novel, and more likely to have experience (or access to experienced collaborators) at presenting your results in a matter that will be of interest to the readers of the journal.
3. There are no obvious platforms for discussion of results that need to be "beat into shape". Most of the work is expected to be "publication ready" rather than at a stage where it requires to be "beat into shape." Unless your are exceptional or have lots of experience, properly editing and "beating into shape" is usually done through collaboration so maybe the first step for you is to find a collaborator with experience in the field. Finding a collaborator is a highly non-trivial task.
4. There are many more disreputable journals that will charge a fee than reputable journals that will not. There are of course some excellent journals that do charge as many work on an open-access model.
5. There is no monetary cost (that I know of) in submitting to a journal that would charge a fee, although you want to be careful not to transfer copyrights before the work is accepted. You could try to submit to an open-access journal but your cover letter should indicate clearly your circumstance and that you do not have funds to pay any author charges: the journal might still continue with the referee process and waive the author charges, but there's no guarantee of that.

Answer 2

Certainly post the paper on the arxiv, to give it some exposure and potentially get some feedback from strangers in your area. Consider sending it to some contacts you had in academia without the expectation of a response, knowing that they are very busy and may not be able to read it. Please understand that, especially if your paper claims a particularly groundbreaking discovery, or if it is not written exceptionally well and in proper style for publications in your field, it may very quickly be dismissed. Once you are confident in it, feel free to submit it to a journal without reviewing costs, and you will get feedback from them directly, one way or the other.