True randomness... exists?
A great article from AskAmathematician about true randomness.
The question is actually geared towards physicists and the tl;dr is: true randomness exists. Take that causality believers.
And as I expected, the experience to prove this is done with photons:
http://www.askamathematician.com/2009/12/q-do-physicists-really-believe-in-true-randomness/