What I don’t get about smart contracts is how the conditions are validated I have a contract that Brad Pitt wins the Oscar in the next 3 years how is that val

What I don’t get about smart contracts is how the conditions are validated I have a contract that Brad Pitt wins the Oscar in the next 3 years how is that validated ? Is there some widely accepted source of truth ? Couldn’t the provider be hacked or be tempted to be fraudulent. I’m assuming the source of truth isn’t the Oscar academy cause web scraping could break easily. Still it’s a lot of faith in human honesty and site security for automatic execution worth millions