Does time exist?

Does time exist? Can we describe anything as absolute? Does traditional physics imply that people don’t have free will? Could physicists have prevented the financial crisis? Hefty questions, all asked by a hefty panel at the RSA’s Time Reborn: A New Theory of Time—a New View of the World (listen to the event here). The event saw the theoretical physicist Lee Smolin, the Financial Times assistant editor and anthropologist Gillian Tett, and the philosopher AC Grayling hurled together in a meeting of the hard and, in Tett’s words, the “slightly squidgy” sciences to thrash out the answers, with Prospect’s own Bronwen Maddox acting as mediator. The discussion explored Smolin’s highly controversial argument that our ideas about society should be influenced by the fierce debate about our cosmology, and that a universe in which time is “real” and in which universal laws continue to change leaves more space for the role of human imagination in solving social and philosophical problems.

In his new book, Time Reborn: the Crisis of Physics and the Future of the Universe, Smolin argues that time is “the only aspect of our everyday experience that is fundamental.” The laws of nature cannot exist outside of time. Instead, they are evolving. This is a direct challenge to the prevailing model—and to Einstein—in which the laws of physics are timeless and unchanging.

Smolin’s arguments come out of what he calls a “crisis in physics”, a term many dispute (see the review by Frank Close, £) but which does reflect a frustration that the promises of string theory have not yet been met. The greatest prize that it was hoped string theory could deliver was the unification of quantum theory with general Relativity. It has not yet done so.

Smolin, whose ideas are intensely controversial within physics, is keen however to take a leap into the social sciences and to play up his ideas’ philosophical implications. Timeless naturalism, he said, leaves us with a universe where “novelty is an illusion, agency is an illusion, will is an illusion.” Temporal naturalism, on the other hand, allows a “real possibility” for the “imagination of human beings... [to take] advantage of the natural capacity to invent novel phenomena.”

Grayling voiced what felt like an unspoken, shared opinion in the room: that the proposals set forth by the soft-spoken but passionate Smolin were extremely “attractive.” In this, they differed from “almost all other metaphysical positions which have turned on the claim that time was unreal,” which are near-universally “unattractive.” He gave the example of Plato’s conception of absolute truths existing outside of time, which had “largely influenced religious conceptions of the universe.” A palpable shudder overtook the assembled humanists in the audience.

Grayling presented Smolin and the audience with what he insisted was a “question not a criticism.” He referred to Mark Twain’s story, "3,000 Years Among the Microbes," in which a man is transported inside a human body, as an example of how “when we get down to the microscopic scale the whole proportion of the universe... changes.” His question, he said, was whether it “is possible that our experience of time... is something that we have taken too far in reading into how things might be in the structure of the universe.”

Could Lee Smolin have come in handy back in 2007? Tett explored the implications of Smolin’s thesis for post-crisis economics. The study of money, said Tett, suffers from “physics envy.” She argued that the middle of the last century saw a dramatic movement away from social science and relativist thinking in economics towards “the idea that an equilibrium could be discovered in the way that money worked, and in the way that physics worked,” a notion particularly dominant in Wall Street and the City in the middle of last decade and which she and Smolin both roundly attacked. As a former anthropologist, she had always resented this assumption that economics could be treated like a hard science, she said.

“The issue wasn’t that economists were borrowing from physics and mathematics, it was that they were borrowing from the wrong type of physics and mathematics,” she said, also saying that she found Smolin’s portrayal of physics to be more flexible than it might seem. If occurrences, whether in physics or society, are “path dependent”—each comes about uniquely, not as an iteration of an unchanging principle—“it has implications for simply assuming that what’s happened in the past will be the perfect guide for what’s happening in the future.”

During a lively Q+A, the boundaries of the debate were further exploded by an audience containing only four physicists and no economists but a healthy spread of chemists, accountants, filmmakers and others. Smolin faced some skepticism from the scientific community—one observer asked how he would explain prime numbers, which we might presume to be the same in any hypothetical alien society. Smolin’s response—that just because something might be invented independently in different places doesn’t mean it is a fundamental truth—produced a quote which summed up his thoughts on human creativity: “just because something is an artefact of human culture, doesn’t mean it’s arbitrary.”

Smolin was challenged repeatedly on his notion that “fundamental” laws continue to change—and he conceded that to say they “evolve” was a metaphor. Did he not have an obligation to say why or how they change? Is this governed by other “meta-laws”? Could he give an example of one that had changed? What could his account explain that prevailing physics could not?

He was also challenged on a second flank—his jump to the application of these ideas to social sciences. For Smolin, the most important idea about humanity overturned by his thesis is “the idea that we’re machines, that we can be emulated by computers.” But some, towards the end of the debate, began to challenge him on this. For a start, is prevailing physics quite as deterministic as he portrayed—that is, that every outcome is determined and in theory predictable? And then, is the model of man-as-machine really as embedded in our view of ourselves as he asserts?

The defining mood of the debate was arguably Tett’s, however, when she said: “isn’t it fabulous that this debate about physics is taking place in a building entitled the Royal Society of Arts?” Clearly, even if he might be guilty of over-stretching metaphors to make his leap into social sciences, it is one that many found immensely stimulating. With that exhortation to reach across the boundaries of disciplines, the debate ended, although Smolin has yet to face a tougher grilling at the Institute of Physics in London, and from his scientific colleagues worldwide.