Scientists are slowly waking up to an inconvenient truth — the universe looks suspiciously like a fix. At issue are the very laws of nature themselves.
For 40 years physicists and cosmologists have been collecting examples of convenient ‘coincidences†and special features in the underlying laws of the universe that seem to be necessary for life, and hence conscious beings, to exist. Change any of them and the consequences would be lethal.
Cosmologist Fred Hoyle once said it was as if ‘a super-intellect has monkeyed with physicsâ€.
To see the problem, imagine playing God with the cosmos. Before you is a designer machine that lets you tinker with the basics of physics. Twiddle this knob and you make all electrons a bit lighter, twiddle that one and you make gravity a bit stronger, and so on.
It happens that you need to set thirtysomething knobs to fully describe the world. The crucial point is that some of the metaphorical knobs must be tuned very precisely or the universe would be sterile.
Example: neutrons are just a tad heavier than protons. If it were the other way around, atoms couldn’t exist, because all the protons in the universe would have decayed into neutrons shortly after the big bang. No protons — no atomic nucleuses, and no atoms. No atoms, no chemistry, no life.
Like Baby Bear’s porridge in the story of Goldilocks, the universe seems to be just right for life. So what’s going on?
The intelligent design movement has seized on the Goldilocks enigma as evidence of divine providence, prompting a scientific backlash and boosting the recent spate of God-bashing bestsellers.
Fuelling the controversy is an unanswered question at the heart of science — the origin of the laws of physics. Where do they come from? Why do they have the form that they do? Traditionally, scientists have treated physical laws of physics as simply ‘givenâ€, elegant mathematical relationships somehow imprinted on the universe at its birth and fixed thereafter. Inquiry into the origin and nature of the laws was not regarded as a proper scientific pursuit.
But the Goldilocks enigma has prompted a rethink.
Cambridge cosmologist Martin Rees suggests the laws of physics are not absolute and universal, but more akin to local bylaws, varying from place to place on a mega-cosmic scale. A God’s-eye view would show our universe as just one amid a vast assemblage of universes, each with its own bylaws.
Rees’s ‘multiverse†is an increasingly popular idea among cosmologists. Only rarely within the variegated cosmic quilt will a universe possess biofriendly laws and spawn life. It would then be no surprise that we find ourselves in a universe apparently customised for habitation; we could hardly exist in one where life is impossible.
If Rees is right, the impression of design is illusory: our universe has simply hit the jackpot in a gigantic cosmic lottery.
The multiverse theory cuts the ground from beneath intelligent design, but falls short of a complete explanation. For a start there has to be a physical mechanism to make all those universes and allocate bylaws to them. This process demands its own laws, or ‘meta-lawsâ€.
Where do they come from? The problem has been shifted up a level from the laws of the universe to the meta-laws of the multiverse.
The root cause of all the difficulty is the fact that both religion and science appeal to some agency outside the universe to explain their lawlike order. Dumping the problem in the lap of a pre-existing designer is no explanation at all, as it merely begs the question of who designed the designer. But appealing to a host of unseen universes and a set of unexplained meta-laws is scarcely any better.
This shared failing is no surprise, because the very notion of physical law has its origins in theology. The idea of absolute, universal, perfect, immutable laws comes straight out of monotheism, the dominant influence in Europe at the time science was being formulated by Isaac Newton and his contemporaries.
Just as classical Christianity presents God as upholding the natural order from beyond the universe, so physicists envisage their laws as inhabiting an abstract transcendent realm of perfect mathematical relationships. Christians believe the world depends on God for its existence, but not vice versa. CorresÂpondingly, physicists declare that the universe is governed by eternal laws that are impervious to events in the universe.
I think this entire line of reasoning is now outdated and simplistic — we will never fully explain the world by appealing to something outside it that must simply be accepted on faith, be it an unexplained God or an unexplained set of mathematical laws. Can we do better? Yes, but only by relinquishing the traditional idea of physical laws as fixed, perfect relationships. The laws are more like computer software: programs being run on the great cosmic computer. They emerged with the universe at the big bang and are inherent in it, not stamped on it from without like a maker’s mark.
Man-made computers are limited in their performance by finite processing speed and memory. So, too, the cosmic computer is limited in power by its age and the finite speed of light.
Seth Lloyd, an MIT engineer, has calculated the number of bits of information the observable universe has processed since the big bang as one followed by 122 zeros.
Crucially, however, the limit was smaller in the past, because the universe was younger. Just after the big bang, when the universe’s basic properties were being forged, its restricted information capacity would have had profound implications.
Here’s why. If a law is a truly exact mathematical relationship, it requires infinite information to specify it. But infinitely precise laws are an extreme idealisation with no shred of real world justification.
In the first split second of cosmic existence, the laws must have been seriously fuzzy. Then, as the information content of the universe climbed, they focused and homed in on the life-encouraging form we observe today. The flaws in the laws left enough wiggle room for the universe to engineer its own biofriendliness.
Thus, three centuries after Newton, symmetry is restored: the laws explain the universe, even as the universe explains the laws. If there is an ultimate meaning to existence, as I believe there is, the answer is to be found within nature, not beyond it.
So the universe might indeed be a fix. But, if so, it has fixed itself. —