A person told me that doing math research independently (alone) is very difficult, because the findings of someone who is not interacting with the experts in a given field of study will most likely not be "novel", that is, they would have already been published before. Is that true ? Can the problem that an independent researcher is working on quickly become obsolete(except for the very famous)? If so, why? Even if research in literature and everything else is well done, is it impossible to do research in mathematics alone?