What came first, quantum fields or the big bang? How can equation that we don't fully understand be written at all? David Tong answers questions from the audience following his talk. Watch the talk here: https://www.youtube.com/watch?v=zNVQfWC_evg Subscribe for regular science videos: http://bit.ly/RiSubscRibe According to our best theories of physics, the fundamental building blocks of matter are not particles, but continuous fluid-like substances known as 'quantum fields'. David Tong explains what we know about these fields, and how they fit into our understanding of the Universe. He covers topics from the Big Bang to the latest developments in particle physics from CERN. The Ri is on Twitter: http://twitter.com/ri_science and Facebook: http://www.facebook.com/royalinstitution and Tumblr: http://ri-science.tumblr.com/ Our editorial policy: http://www.rigb.org/home/editorial-policy Subscribe for the latest science videos: http://bit.ly/RiNewsletter