A WALK in the woods. Every shade of green. A fleck of rain. The sensations and thoughts bound in every moment of experience feel central to our existence. But physics, which aims to describe the universe and everything in it, says nothing about your inner world. Our descriptions of the wavelengths of light as they reflect off leaves capture something – but not what it is like to be deep in the woods.
It can seem as if there is an insurmountable gap between our subjective experience of the world and our attempts to objectively describe it. And yet our brains are made of matter – so, you might think, the states of mind they generate must be explicable in terms of states of matter. The question is: how? And if we can’t explain consciousness in physical terms, how do we find a place for it in an all-embracing view of the universe?
“There is no question in science more difficult and confusing,” says Lee Smolin, a theoretical physicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada.
It is also one that he and others are addressing with renewed vigour, convinced that we will never make sense of the universe’s mysteries – things like how reality emerges from the fog of the quantum world and what the passage of time truly signifies – unless we reimagine the relationship between matter and mind.
Their ideas amount to an audacious attempt to describe the universe from the inside out, rather than the other way around, and they might just force us to abandon long-cherished assumptions about what everything is ultimately made of.
Modern physics…