You don't need blockchains to solve the fake news problem. The system that appears to be creating the problem (the world wide web) also provides a very simple solution to combat fake news. It's called linking your references. If even the "trusted" news outlets would give links to references rather than just authoritative prose, we wouldn't have this problem. If there is an article about a bird flu virus breakout in Iowa, how can one know if that is true or false without a link to an original source like an alert on the CDC website. When trusted news sites don't link to references it sets a precedence that references aren't required. Once that's the norm anyone can say anything and the reader can't distinguish truth from false unless they spend the time to do their own research. If a news site has done the research then they should provide the links to that research. Factual statements should link and reference the original source and any photos or videos used should link and reference the original source. In the olden days (pre www) newspapers could get away without giving links to the original source because the technology didn't support it. In today's world, when it is so easy to link to the sources, they should not be allowed to get away with just authoritative prose. One should assume that all news, even from trusted sources is fake (or just opinion) if it is presented without any links to references.