who is robertr silverberg and why does his name ...?

why i wonder does his name and picture come up for the book written by walker chapman, the loneliest continent 1969 in fact it says he has written 958 books

And that's when touchstones are handy: Robert Silverberg. I saw him one year at a science-fiction convention. He was grumpy...
No idea about the second part of your question, but I dare say someone will come along with the answer. Otherwise, you could always ask again in the Science Fiction Fans group.

>1 nakeddog: As noted in the one review of The Loneliest Continent, "The author is Richard Silverberg, writing under a pseudomyn--a man who has written seemingly hundreds of books."

Edited... again. So, to be extra clear, Walker Chapman wrote The Loneliest Continent under the pseudonym (ie, fake name) Richard Silverberg, which has nothing to do with the science fiction author Robert Silverberg.

Because Walker Chapman is one of Robert Silverberg's pseudonyms.

Wow! I wonder why he needs so many pseudonyms?!

>6 krazy4katz: At his peak, he both a) was extremely prolific and publishers might balk at publishing multiple stories per month by the same author, and b) was writing a lot of erotica which he wanted to keep pseudonymous and separate from his other work

>1 nakeddog: Regarding your last point, guy was wildly prolific, and also that list contains works where he was an editor, wrote the introduction, has a single short story, etc, etc.

>1 nakeddog: Because he wrote the book, and on LibraryThing, authors who write using more than one name get all their books collected under the most common, or popular, or "correct" name. I guess this is really your question.