Whether they are trying to reduce global warming, improve food distribution, or even revolutionize "communication protocols" [1], what are startups that you, the Hacker News reader think will change the world, or are currently changing the world? I encourage you to put your own startup if you think it will change the world.
[1] http://online.wsj.com/articles/yo-this-app-isnt-so-dumb-1407714995
That being said, I see new business opportunities in making sense of exorbitant amounts of data. This can help push further research in areas you have mentioned and obviously many others as well.