Comment by dosran

I've been following Jeremy's blog for some years now and although I don't always understand everything, I appreciate it for being a relatively accessible look into the research that's going on.

> you can implement ciphertext-ciphertext multiplication: x.y = ((x^2 + y^2) - (x^2 - y^2))/4

However this one part confused me - the RHS seems to simplify to y^2 / 2. Is there a mistake here or is this specific to the polynomial fields being worked in? (Or am I being dumb?)