What if the universe is just one big computer?NASA/ESA/J. Lee and pro500/Shutterstock
The following is an extract from our Lost in Space-Time newsletter. Each month, we dive into fascinating ideas from around the universe. You can sign up for Lost in Space-Time here.
My colleagues and I have a running joke: time isn’t real. Oh, you thought that deadline was tomorrow, but it’s actually today? Time isn’t real; that explains it. The 1980s can’t possibly be 40 years ago, can they? Nah, mate, time isn’t real. If aliens were looking at Earth right now from a distant ship, would they see dinosaurs or just seas of magma? Time is definitely not real.
But, like so many jokes, there’s a kernel of truth there. In this case, it’s not that time isn’t real, but rather that we really, really do not understand it – and by “we” I don’t just mean me and my pals, but humanity as a whole. Physicists and philosophers have been reckoning with the concept since, well, time immemorial, and while there are many ideas floating around (some more plausible than others), there still aren’t any solid answers.
I took the question to Stephen Wolfram, a physicist and computer scientist who has created some of the most useful computing tools in physics. For decades, he’s been working on what he calls “The Wolfram Physics Project”, an immense effort to redefine physics in terms of computation, rather than the typical maths and thermodynamics used by most physicists and cosmologists to understand the universe. To say the project has been controversial in scientific circles would perhaps be an understatement. For starters, his ideas on time require the universe to be essentially one big computer. If it’s true, this idea has the potential to finally explain what time is, why it flows smoothly forward, and why we can’t tell the future. So, I called him up to have a chat about it.
