Add error handling for no authors found

app.py

@@ -86,6 +86,8 @@ def get_papers(
     hf_user_name = hf_user_name.preferred_username
     positive_arxiv_ids = positive_arxiv_ids.split(",")
     potential_authors = query_author(author_name)
+    if not potential_authors:
+        raise gr.Error("No authors found with that name")
     author = get_author_from_options(potential_authors, positive_arxiv_ids)
     papers = get_arxiv_paper(author["papers"])
     papers = sort_by_date(papers)