Our expanding collaboration with other fields is broadening our understanding of computation, and it is appropriate to take stock of where we are. It is likely that the question "What is computation?" will never be completely settled, just as the question "What is life?" is never settled in biology and "what are the fundamental forces?" is never settled in physics. Engaging with our question is valuable even if we may not find a completely satisfactory answer.Well I know exactly what computation is, thanks to the beautiful paper of Alan Turing in 1936. My initial reaction was to stay far away but then I realized I had a forum to truly make the point that Turing had the right notion from the start. But as I started writing I realized I didn't have to make any new arguments, Turing himself anticipated the future objections. I just used his words.
The Ubiquity "What is Computation?" papers are coming out once a week. My article, The Enduring Legacy of the Turing Machine, was publshed last week.
Also check out the article by David Bacon who turns the question around. Instead of asking "Can the universe compute beyond Turing Machines", he asks "Why can the universe compute at all?".