Elegant Equations

30 Mar 2013

Prof. Trevor Palmer sent in the following piece, gleaned from the New Scientist 'special issue' of 2nd March. The headline on the cover asks, 'We've run out of explanations for the Universe. What's next?'. In the first article, 'Roots of Reality' Brain Greene, a theoretical physicist at Columbia University, New York, asks, 'what makes us so sure that mathematics can reveal nature's deepest workings?' He adds, 'deciding which mathematics to take serious is as much art as it is science'. Greene admits that no one knows how things will turn out but concludes, 'only through rational pursuit of theories, even those that whisk us into strange and unfamiliar domains - by taking the mathematics seriously - do we stand a chance of revealing the hidden expanses of reality'. After that, in 'The Dark Side', New Scientist consultant Steven Battersby writes, 'our established picture of the universe is supremely successful - may be because most of it is made up.' It depends on two elusive theoretical concepts, dark matter and dark energy. Battersby continues, 'we don't know what these dark apparitions are but they seem to be almost anything.' He goes on to quote Robert Kirschner, a cosmologist from Harvard, 'our lack of answers gives us a sense not of desperation, but of inspiration.'

Turning to particle physics, in the next article, 'Flawed Genius,' Matthew Chalmers, a freelance writer, suggests, 'the particle jigsaw is complete - and that's where the problems start.' The discovery of the Higgs boson may have provided confirmation of the existence of the final element of the theoretical concept known as the 'standard model' - but it doesn't prove the model to be correct, or, at least, complete. A complete model must be able to generate correct predictions.

He concludes, 'the standard model's equations may be elegant but to give them their predictive power, they must be fed more than 20 'free' parameters, such as particle masses, by hand. A truly fundamental theory would use the power of quantum theory, or perhaps some deeper idea that nobody has yet thought of, to prune that thicket.' Finally, in 'Are we Nearly there Yet?' consultant Michael Brooks writes about unsuccessful attempts to formulate a unified theory incorporating quantum mechanics and general relativity and comments, 'the quest for an ultimate theory may have stalled - but let's not call the journey off.' He ends by quoting Paul Davies of Arizona State University, who suggested that anyone who searches for an ultimate theory purely for its own sake risks ultimate disappointment, as well as perhaps making the same mistake as those who believed at the end of the 19th century  that physics was complete, and continued, 'you could come up with some marvellous scheme, and you could put it up in a stained glass window and celebrate it as a wonderful achievement of the human intellect. But there would always be the possibility that someone comes up with a better one.'