The Future of Fake Media

I think by current technology, fake media will be undetectable as a fraud. There are now video versions of this where you can get someone's mouth to move in the appropriate way so it looks like they're delivering the fake audio. The second thing we discovered from this was that and this also kind of applied to this question of like when you have AI and agents how would you be able to tell if you're human or not? I've imagined there must be some blockchain based way of ensuring against that but where are we going with that?