The Magic of Metaphysics
Christopher Timpson, Fellow and Tutor in Philosophy at Brasenose and CUF Lecturer in the Faculty of Philosophy, tells us why modern physics needs philosophy – and vice versa
Interview by Olivia Gordon, Oxford Today
I’m sitting in Brasenose’s senior common room with Dr. Christopher Timpson, discussing quantum teleportation, a scientific advance which allows an object to disappear from one place and be recreated in another, without being transported between them. This may sound like an episode of Dr. Who, but it’s just an ordinary Friday morning tea-break conversation for Timpson, whose specialist subject is the philosophy of physics.
Oxford is generally acknowledged as the world’s leading centre of research on the intersection of physics and philosophy. The University accepts around 15-20 undergraduates each year to study this joint honours degree, which was introduced in the late 1960s (along with a degree course on mathematics and philosophy). Physics and philosophy have a natural connection, as Dr. Timpson explains. Both are ‘trying to find out how the world is’.
Dr. Timpson studied physics and philosophy at Oxford as an undergraduate, which involved a serious training in each individual subject, before returning to teach the degree. What led him to the field? ‘Well, a chance to look at the questions I’ve always been interested in,’ smiles Timpson amiably, clinking his teacup. ‘It’s an excuse, really, for a day job pursuing fascinating ideas. What is the nature of space and time; how should we understand theories of the very small and the very fast; why are things as they are; what is going on?’
And what is going on? I ask. Dr. Timpson explains that his work focuses on exploring quantum reality. I’m still not sure quite what this means, so he talks me through one famous conundrum that continues to interest him - the thought experiment of Schrödinger’s Cat. The classical laws of physics – the ones underlying the way most of us perceive the world – suggest that a single object – a cat, for instance – can only be in one given place, or can only be one given way, at any one moment in time. But the laws of quantum physics, first adumbrated by Max Planck and Albert Einstein in the early years of the 20th century, proved that an object can - in some sense - exist in two places at the same time, while also being in neither. It’s a mind-boggling state called ‘indeterminacy’, and it forces us to rethink the way we understand everything, including our binary idea of life and death for pets. The thought experiment of Schrödinger’s Cat imagines that if an atom, being used as a trigger, decays, a lever will be pressed, and a cat in a box will be given a dose of cyanide – so if we open the box we would expect the cat to be either dead or alive. But because of quantum indeterminacy as to whether - or when - the atom decays, the cat is rendered indeterminate too: neither dead nor alive, but left in some sort of metaphysical limbo..
This is not only baffling to a layperson interviewer but also to those expert in quantum physics, Dr. Timpson reassures me. ‘Ever since its inception, quantum theory has been puzzling,’ he says. ‘I spend a lot of time working with these puzzles, asking what it means for quantum theory to be a good description of the world.’
Quantum physics’ being difficult to ‘get one’s head around’ is the ultimate truism – but, Dr. Timpson points out, the theories of classical physics, from gravity to electromagnetism, are also ‘stranger than you realise when you start thinking hard about them’. He works with research scientists who perform experiments. But his own work is largely ‘desk based, when not involving striding up and down scratching one’s head.’ A typical day in his life involves a lot of thinking - using conceptual, hypothetical analysis to ask what our world is like and our place in it, and how some of the remaining mysteries of quantum theory might be resolved.
Dr. Timpson’s work engages particularly with the field of quantum information theory, active since the 1980s, which investigates new possibilities for information processing using quantum theory as opposed to the binary determinacy of 0s and 1s used in classical computing. ‘Quantum mechanics differs from classical physics in mind-bending ways. It offers new ways of being,’ says Timpson. ‘You can have an infinite number of distinct states that the very simplest information storage device could be in.’ The way we communicate could be transformed, he says – very real possibilities for our future include exponentially more powerful computers, completely secure cryptography, and quantum teleportation, which, he acknowledges, ‘is a bit like magic’.
Ultimately, asking philosophical questions takes physics further, and vice versa, Dr. Timpson believes. Our understanding of the link between the two disciplines dates back at least to Aristotle, who coined the philosophical term ‘metaphysics’ for trying to find the basic principles of reality. ‘Philosophers have a pretty bad track record of saying “Things must be thus and so!” and then finding things are not thus and so,’ says Dr. Timpson, citing the belief that space is flat. ‘It seems plain that any metaphysics worthy of the name is going to have to be deeply responsive to what current physics tells us.’
Timpson, who is married to a fellow physicist with whom he has a young daughter, is also fascinated by the philosophy of mind, philosophy of language, epistemology, and the history of twentieth century Anglophone philosophy. He is equally passionate about his duties as a Brasenose Cellararius (wine fellow), which involves buying and choosing wines for the college. ‘That’s a very serious business,’ he says. ‘Almost as serious as probing the fundamental nature of reality.’