I just put in the GoWA disc in to play the Last of Us demo, but my PS3 kept going black.
I got frustrated so I visited these forums and found out I was not the only one.
I read that I needed to boil the discs? That seemed a little too crazy, particularly that my discs are clean, so I instead:
Game -> Game Data Utility -> Found any mention of God of War: Ascension (I found 3, including MP beta) -> Triangle -> Delete (Make sure it is Game Data Utility you delete from so you don't lose any save files)
Signed in with PSN (before launching disc)
Launched game and got as expected an update prompt for 1.07 (previously had 1.03 installed)
Download and install all updates
Disc now boots up as normal
Edit: If you followed all these steps and still having trouble, eject disc, clean back of it, insert disc and should work fine!
I hope this helps anyone else experiencing this issue!