One way to solve this problem is to add a custom column to contain the alternative author(s) names. This is type "Comma separated text, like tags", but with the checkbox "Contains names" checked.
Next, you create a "Grouped search term" (preferences -> Searching) that combines the author column and the new custom column. For example, and assuming the lookup key for your custom column is "#real_authors", you could create a group search term "all_authors" that contains "authors, #real_authors".
Once you have done both steps, then you can search for authors in either column by searching for all_authors:"Some Name". It will find "Some Name" in either authors or #real_authors.