There is some speculation that Google may be able to begin checking content for factual accuracy in the future, but for now, we have ‘best answer’ results in search in top ranked positions.
There are many complications around establishing facts, such as new discoveries making old ‘truths’ out of date, or overwhelming opinion, belief systems or religion being read as factual by vast sectors of the community.
Aside from these issues, plenty of online content is written to be purposefully fictional, yet should still gain rank and web traffic because it may well be what the user is searching for.
If any type of truth engine is applied to Google rank in the future, it would have to be strictly limited to facts that are undeniable, such as a person’s name or age, or the weight of a m³ of water. Features that are not ever influenced by opinion.
When it comes to best answer content, this is typically a result from a website that succinctly answer’s a user query where the query is structured like a question – like “what is the weight of one cubic meter of water?” Try this query yourself.