- The laws of physics may not be eternal, unchanging truths, but rather habits that formed from cosmic chaos.
- Cosmologist João Magueijo argues that physical constants, such as the speed of light, emerged as the universe cooled and settled into order.
- In the first fraction of a second after the Big Bang, the universe was too hot and turbulent for stable laws to exist.
- The universe’s patterns and symmetries, like the constancy of the speed of light, formed as it expanded and cooled.
- Scientists may be rethinking the fundamental nature of the laws of physics and their role in the universe’s evolution.
Imagine a universe without rules—a formless, flickering expanse where gravity does not bind, light does not travel, and time has no direction. This is not science fiction, but the primordial state some now believe preceded the cosmos we know. For centuries, scientists have treated the laws of physics as eternal, unchanging truths, carved into the fabric of reality like commandments from a cosmic architect. But what if they are not laws at all, but habits—patterns that crystallized from chaos, like ripples freezing into ice? For cosmologist João Magueijo, this question has haunted his career. From late-night scribbles on napkins to high-stakes debates at Cambridge and Imperial College London, he has pursued a heretical idea: that the constants of nature, from the speed of light to the strength of gravity, were not written at the beginning of time, but emerged as the universe cooled and settled into order.
The Universe Had No Rules at First
Magueijo’s latest proposal, detailed in recent papers and a forthcoming book, argues that the so-called laws of physics are not fundamental, but emergent. In the first fraction of a second after the Big Bang, he suggests, the universe was too hot and turbulent for any stable laws to exist. Instead, physical constants fluctuated wildly, and symmetries we now take for granted—like the constancy of the speed of light—had not yet formed. Only as the universe expanded and cooled did these patterns stabilize, much like how water molecules settle into a hexagonal lattice when freezing into snowflakes. This challenges Einstein’s assumption that physical laws are fixed across space and time. Magueijo’s model, known as “cosmic natural selection” or “emergent law theory,” draws on principles from thermodynamics and statistical mechanics, suggesting that what we perceive as universal laws are actually the most probable outcomes of early cosmic evolution. If correct, it would mean that physics is not a set of divine prescriptions, but the fossilized residue of a violent, formative epoch.
Challenging Centuries of Scientific Faith
The idea that physical laws might change over time is not entirely new. In the 1930s, Paul Dirac first speculated that gravity might weaken over cosmic time. In the 1980s, John Barrow explored varying constants in cosmology. But it was Magueijo’s development of the theory of varying speed of light (VSL) in the late 1990s that brought the idea into mainstream debate. He proposed that in the early universe, light traveled much faster than it does today—a radical alternative to cosmic inflation, the dominant theory explaining the universe’s uniformity. While inflation posits a rapid exponential expansion smoothing out irregularities, VSL suggests that light could have reached all corners of space quickly enough to equalize temperature without inflation. Though controversial, the theory gained traction for solving the “horizon problem” without requiring undiscovered fields or particles. Over time, Magueijo’s thinking evolved: if the speed of light could vary, why not other constants? Why assume any law is truly fixed? This skepticism laid the groundwork for his current view—that laws themselves are historical artifacts of cosmic cooling.
The Rebel Behind the Revolution
João Magueijo’s journey has been shaped by defiance and curiosity. Born in Portugal and trained in theoretical physics at Cambridge, he has always operated on the fringes of orthodoxy. Colleagues describe him as brilliant, combative, and unafraid to challenge giants like Stephen Hawking and Alan Guth. His motivation, he says, stems from a deep discomfort with unexplained assumptions. “Why should the universe come with a rulebook already written?” he asks in interviews. “That’s more theology than science.” Magueijo is not alone—physicists like Lee Smolin and Roger Penrose have also questioned the absoluteness of physical laws. But while Smolin suggests laws evolve through black holes in a multiverse, Magueijo focuses on thermodynamic emergence within a single universe. His work bridges cosmology, statistical physics, and philosophy, driven by a singular impulse: to strip away metaphysical baggage and rebuild physics from observable principles. This quest has cost him mainstream acceptance at times, but earned him a devoted following among those who believe science must question its own foundations.
Implications for Physics and Reality
If Magueijo is right, the consequences ripple across science. The Standard Model of particle physics, general relativity, and even quantum mechanics may not be final theories, but approximations valid only in our current cosmic epoch. Experiments searching for variations in fundamental constants—such as those measuring the fine-structure constant in distant quasars—take on new urgency. A 2020 study published in Nature Astronomy reported tentative evidence of such variation, though still debated. Moreover, if laws emerge from chaos, other universes—or regions of our own—could have entirely different physics. This reframes the “fine-tuning” argument: rather than needing a designer to set perfect constants, the universe may have settled into its current state through natural selection of stable configurations. For cosmologists, it suggests we must study the early universe not just as a hot dense state, but as a phase transition where order arose from disorder.
The Bigger Picture
Magueijo’s theory is more than a technical proposal—it’s a philosophical shift. It aligns with a growing movement in physics that sees the universe not as a machine governed by eternal laws, but as a dynamic, evolving system. This echoes ideas in complex systems, where global order emerges from local interactions without top-down control. Just as traffic patterns arise from individual drivers, or life emerges from chemistry, the laws of physics might be the universe remembering what worked. This doesn’t diminish their power—it deepens our awe. To see nature’s rules not as decrees, but as outcomes of cosmic trial and error, is to view reality as profoundly historical, contingent, and alive.
What comes next may be a new era of observational cosmology. Upcoming telescopes like the Vera C. Rubin Observatory and the Square Kilometre Array could detect subtle shifts in constants over time or space. If evidence mounts, textbooks may one day say not that “the speed of light is constant,” but that “it became constant.” And João Magueijo, the rebellious cosmologist who dared to ask where the laws came from, may be remembered not as a fringe figure, but as the one who made physics humble again.
Source: New Scientist