Saturday, 17 March 2012

About Time

About Time: From Sun Dials to Quantum Clocks, how the Cosmos Shapes Our Lives by Adam Frank

Daily Telegraph, 17 March 2012

St Augustine, the fifth century theologian and Church father, famously discussed the nature of time in Book XI of his Confessions: ‘What is by now evident and clear is that neither future nor past exists, and it is inexact language to speak of three times – past, present, and future. Perhaps it would be exact to say: there are three times, a present of things past, a present of things present, a present of things to come.’ For centuries it was a description as good as any.

Today there are many books on the nature of time as we experience it and even more on cosmic time as revealed by science. Yet few attempt to recount the entwined narratives of cosmic history and human time as a unified whole. Adam Frank’s About Time does just that. An astrophysicist at the University of Rochester, he and many of his colleagues believe that ‘the Big Bang is all but dead’. 

Frank and the others do not doubt the scientific narrative of cosmic evolution over the last 13.7 billion years, only the ‘bang’ in Big Bang. The moment of creation with no before is being questioned because of the very precision of the science that gave the notion ‘a measure of reality in the first place’. ‘The roots of cosmology cannot be reworked without a new conception of time, including its origins and its physical nature,’ argues Frank in this excellent book.

Cultures have always needed a cosmology to understand their place in the framework of creation. Frank shows how, as our ideas about cosmology and cosmic time have changed, human time has also changed. Acknowledging that the broad sweep of history, science and time which follows focuses primarily on the cultural development associated with the West, for Frank the most potent and obvious example of the binding of human and cosmic time is the industrial revolution with its roots in the scientific discoveries of Newton and its radical reformation of everyday life.

The first intimation of the modern structured day was born in the medieval monasteries. From sunrise to sunrise, the monks followed the horae canonicae, the rounds of worship beginning from sunrise (matins) through midday (sext) and sunset (compline) and through the night to matins again. 

Yet the division of the day into 24 hours was an invented by Babylonian astronomers, but it did not gain widespread acceptance until the advent of mechanical clocks in the 14th century. No one knows who invented the clock and in particular its key component – the escapement, the notched metal rings that allow gravitational energy stored in a hanging weight to be regulated and regularly released.

Prague's famous town clock
By the end of the 15th century, the town clock was a matter of civic need and pride. Soon the ancients’ Earth-centre universe gave way to Copernicus’s sun-centred cosmos and then to Newton’s clockwork universe, with space and time as absolute, unchanging and eternal. 

Throughout 18th century the new universal laws of physics reworked human conceptions of the heavens and before long led to machines that paved the way to industrialisation. And today we describe times in digital format – for example, 1.17 p.m. ‘It’s a new time that we have created in our hyperdigital, telepresent, instant-messaged society,’ says Frank. 

After 50 years of trying, physicists still lack a theory of quantum gravity – ‘a theory of space and time on scales so small entire universes could be bound in an atom’. Consequently cosmology, and our understanding of time, remains incomplete and full of speculation. Is the universe one in a long line? Could there be many bangs going off all the time, creating simultaneously existing universes – a multiverse? These ideas might sound like science fiction but they are being seriously pursued by some theorists while others, reports Frank, hope for ‘something else, something better, something not yet imagined’.