My collaborator and I submitted an article to a special issue of a journal. He did most of the writing of the article, while I did the technical work such as running simulations, generating plots, and typesetting the article in LaTeX.
After two revisions, the article has been accepted with major (one reviewer) and minor (the other reviewer) revisions needed. We were given a relatively short (3 weeks) deadline to make the revisions, due to the deadline for making up the special issue of the journal.
Unfortunately, my collaborator has suddenly become unreachable by email for the last 5 days. As we're living in different cities, I have no idea if he experienced a medical or family emergency, or if he suddenly is no longer interested in the article, or is no longer alive? (He's probably alive, touch wood, my point is just that I feel quite confused with the situation, and my imagination is running a bit wild at this point.)
Question: How should I proceed with a short deadline for revising our journal article submission, if I am unable to reach my collaborator?
I could try to do the rewriting completely by myself, I believe this is do-able. However, is it "kosher" for me to submit the article revision, if I don't hear from him before the submission deadline?
I could also do nothing, and wait, hoping that he becomes reachable again, but the longer I wait, the greater the risk that we'll miss the deadline and have to go through the entire journal article acceptance process again.
I'd really appreciate some advice as this is quite confusing, and it feels strange to be so close, yet so far, in getting this journal article finally accepted and published.
A few days after I posted this question, my collaborator finally responded to my email. He didn't explain exactly why he was out of communication, but I am inferring that he was really busy with things on his end. We'll be working this week to get the paper submitted on time, it will be a bit tight but I think it's manageable.
Thank you to everyone for your suggestions, fortunately I didn't have to use them this time, but hopefully someone else who encounters this situation in the future can use these really helpful suggestions.