In summer 2010, we paid a visit to Mr Martinus Veltman at his house in a beautiful town close to Utrecht, the Netherlands. Veltman shared the 1999 Nobel Prize in physics for his work on particle theory.
We had a relaxing conversation widely about science and life. Regarding what the currently most important big question in science is, his answer was identical to the title of a 1944 science book written by physicist Erwin Schrödinger — What is life?