I am not searching down all the whitepapers for you, if you truly want to learn then you will need to dig into the myriad mathematician's white papers against Proof of Stake.

Here is one link, and you can find several more.

https://download.wpsoftware.net/bitcoin/pos.pdf

Now, that is a PDF, and I do not recommend blindly opening PDFs. This is by Andrew Poelstra, who is a mathematician at Blockstream.