Saw a trailer for an upcoming underwater science fiction movie, forgot the name of it

Scientists discover a bright opening or portal deep underwater. We see one of the scientists walk through that opening or portal. He sees or lives an alternate life/timeline where he never leaves a past lover.

I know the above description is kinda vague, but that is all I remember. The movie doesn't look to be funded by a major Hollywood studio (looks like it originates from a Scandinavian country?). Looking for the movie title.