heyo! Explainpaper lets you upload a research paper PDF. If you don't understand a formula or sentence, just highlight it and the tool explains it for you
I built this a few weeks ago to help me read a neuroscience paper, and it works pretty well! I didn't fine-tune GPT-3, but I do take a lot of context from the paper and feed that into the prompt (not the whole paper).
Ppl have uploaded AI, biology, economics, philosophy papers and even law documents. Works in Chinese, Japanese, Spanish, French and more as well!