BIG READ: The cold comforts of quantum

In 1963 the young Sir Roger Penrose, today regarded by many as the world’s leading living physicist, was on a research fellowship in the US when John F Kennedy was assassinated. The talk all day long was about the latest conspiracy theories and there was barely any response when he asked his peers for help with a proper theory, a mathematical one of his own.

Miffed, he chose to travel to a particular destination with a Hungarian member of the party, known for his reluctance to speak English, and his reluctance to speak at all. On the silent drive Penrose’s problem was solved, when a ray of light literally hit him through the windscreen. He knew then he had to replace the point of light in his calculations with a ray to add a fifth dimension to the four of the space-time continuum we know in our daily lives.

And so the maths of twistors was born. Twistors lie at the basis of conceptions of multiple dimensions, dozens of them, on which are built several forms of string theory, possibly the basis for uniting quantum mechanics and classical physics into a Theory of Everything, the Holy Grail of the physical sciences. Not to speak of the cultural industry that has generated billions in all currencies through the decades, with carte blanche given to science fiction to go where no-one has dared to go before.

So, can one say that the mathematics of twistors, regarded by some as Sir Roger’s most impactful contribution to science, was a beneficent outcome of the assassination of JFK? Penrose, now well into his 80s, will probably give his trademark wry smile to dismiss it, but then add that little is understood about flashes of genius, before recounting how one of his own during a canteen lunch opened the door to black holes.

Penrose’s other great preoccupation, apart from physics, is consciousness studies, and in this field, he and his peers are grappling with the conjecture that quantum mechanics has something to do with giving sentience not only to advanced organisms but also to nature at its most basic. Last year, a team of scientists found that quantum mechanics allows information tunnelling during super-radiance in the amino acid tryptophan, which is basic to all cellular walls. In the lay person’s terms, this allows cells to act like minuscule computers.

We are still far from using quantum computers in daily life, since they are hugely expensive and need to run in temperatures that are colder than deep space to escape Murphy’s law: if something can break down, it will. Bacteria have beaten us to such computing, if the tryptophan researchers are right. They even came up with a calculation of the number of logical operations that life on Earth might have made in its 4.3-billion years of existence: 10 to the power of 60. If we were to count at one number per second, that would come to twice the age of the whole universe.

This year quantum mechanics is 100 years old, if you take 1925 as its start, when Max Born used the term for the first time in a paper. Later that year, Erwin Schrödinger published an iconic equation that turned the world upside down, as it seemed to show that at its base, reality is indeterminate and just weird — Schrödinger himself was among a group of scientists who had sleepless nights about what the maths told them.

He created the most famous cat in history, not in an attempt to cutely explain quantum mechanics as is usually assumed, but to show that it is absurd: how can it be dead and alive at the same time? But in a precedent that would be set for many scientific advances, the public imagination took possession of the poor feline to use it to show that all sorts of states can occur at the same time, and today it is the emblem for quantum weirdness.

Scientists are confronted with a peculiar problem in contemporary times. The maths behind it all can become terribly complex, despite the uncanny elegance and minimalism of equations like the most famous of all, Albert Einstein’s E = mc2. For instance, after devising twistor theory, Penrose rejected the idea that reality can exist in 26 dimensions, as some theories had it. But when decades later he came around to at least their mathematical viability, the field he had created had advanced so much that the future Nobel prize winner had to take freshman classes to catch up.

To convey to lay people, who often include scientists in other disciplines, what the heck they mean physicists have to resort to metaphors and other forms of language that can become wildly inaccurate but are then embedded in the public consciousness.

So “entanglement” tries to describe the linkages that can exist between particles over billions of light years, and how, when you tweak one, the other gets tweaked too. Einstein rejected this, and called it “spooky action at a distance”, which he shouldn’t have because, as one of the grandfathers of quantum mechanics by conceiving of quanta in light in 1905, he embedded it in the public’s mind that it had vaguely supernatural aspects.

In another famous quote, he said, “God does not play dice with the universe,” which millions of ecstatic Christians take as validation that God has plan with us all. However, the rest of his quote was redacted. He wasn’t troubled so much by quantum mechanics being based on probabilities rather than tangible substances, as that the “ghosts” are talking to each other: He added, “with God then using telepathy between particles.”

“Wormhole” is another metaphor, used to describe highly abstract topological features of space-time mathematically, theoretically allowing instant travel across vast distances. Quantum mechanics may make this a reality according to some theories, and when physicist John Wheeler wryly wrote that fellow physicists might be excused for using the word “wormhole” to “vividly” describe it, it became the excuse for science fiction to go wild.

So common has this metaphorising of science become that the scientists themselves, well knowing the inappropriateness of such similes, use them not only to explain to the neighbour what they’re doing, but in talking to each other. The same applies to “quarks”, the most basic of particles. It was a random name chosen from James Joyce’s novel, Finnegans Wake, by particle physicist Murray Gell-Mann when he co-discovered it through impenetrable maths. Joyce explained that he had heard it at a German market, where it meant “trivial nonsense”.

Gell-Mann’s fellow founder of the particle, George Zweig, preferred the term “ace”, but once again the public imagination seized on “quark” because Gell-Mann pronounced it like “quart”, when you order beer.

So quantum weirdness also exists in quantum mechanics having the power to invade large spaces of contemporary culture with such vague descriptions, while at the same time being extremely accurate when it comes to its use in our daily technology. Earlier this year Quantum Day was held. One website published a full calendar of 100 events on that day across the world. At the accuracy end of the spectrum were engineering conferences on arcane aspects of quantum technology, especially quantum computing. On the other, speculative end were launches of silly games such as quantum sudoku, around another quantum canard, that ordinary arithmetic can have two outcomes at the same time.

Recently Canadian author Anne Michaels played with quantum metaphors in her Booker-shortlisted novel Held, while our own Charl-Pierre Naudé used it to droll effect in his The Equality of Shadows, in which whole fuel stations appear out of the blue for a few days before vanishing again, without any apparent rhyme or reason, the only proof the fuzzy photographs Naudé provides in the novel.

Quantum culture can be very good, these examples show, but it is on the accuracy end that quantum mechanics really governs our lives today. The compartmentalising of our space-time into hyper-exact times and geographical co-ordinates are executed every second to margins of error of tenths to minus 16 powers. The benchmark is the transition times between certain quantum states of caesium gas, which are housed in a number of atomic clocks across the world. (You can order one for $50,000 from a US company).

Several are on board satellites circling or stationary above the Earth. Without them, the IT revolution would not have been possible, the internet depends on them, as do GPS systems and all their offshoots in the likes of Google Maps as well as the operation of cellphone networks. There are problems, though, their signals have to be adjusted to take into account general relativity and the interference of receiver deficiencies. Next time Google Maps dumps you 50m or so from your destination, remember it is not the fault of quantum mechanics, it’s the other guys.

There are more serious problems for quantum mechanics, to such an extent that the word “crisis” arises every now and then. Part of it is tied to a parallel crisis, the cosmological one. Though we depend so much on the accuracies of quantum effects, these occur on such small and cold scales that many aspects of quantum mechanics can never be proved. However, on the cosmological scale some can be tested or approached from different viewpoints.

Quantum thermodynamics states that there is no vacuum, and that space-time is permeated by a base energy, or cosmological constant. But what to do if the three major methods used to measure it deliver divergent results? Further muddying the waters are dark energy and dark matter. Not only do the molecules that make us up largely exist of empty, or ultra-low-energy, space, we are wallowing in these two as well, for together they make up about 95% of everything that exists.

Dark energy is what is behind the well-documented expansion of the universe. What this means is, no matter how hard you exercise or how well you eat, you are prone to growing larger. Fortunately the rate is rather slow, 73km per second per megaparsec, or 3.26-million light years, and gravity and other attractive forces can overcome it — there is a kind of tug-of-war going on inside us.

The eight years or so after the 1925 introduction of the term quantum mechanics have been called the Golden Age of Physics, since most of its principles were puzzled out in that time. The handbooks produced then are still in use today, and the more philosophical treatises are undergoing a revival, such as Schrödinger’s What Is Life? Also a philosopher who admired the ancient Indian texts of the Upanishads, he was the first to raise the possibility of quantum consciousness as the deep origin of life.

From the start, the next great breakthrough, a Theory of Everything, in which quantum mechanics is melded with gravity, the one force not described by it, was expected to come soon. After a century of trying, many physicists have become quite anxious about their lack of progress, especially when they have to lobby Donald Trump-like ignoramuses for more funding of experimental facilities, such as the enormous CERN (European Organisation for Nuclear Research) particle collider running for 27km deep under a suburb of Geneva, Switzerland. (Total cost of building the collider and two experiments: $18bn; annual cost of running it: $5bn.)

Quantising gravity is how many scientists conceive of the challenge, but this could merely be due to the dominance of all things quantum in science fiction and metaphorising about science. If gravity were quantised, you could then in a flight of imagination conceive of falling as happening in one of those stop-motion sequences, or like a figure in a William Kentridge video. Yet many sports and artistic forms, from skydiving to ballet, are devoted to eliciting the beauty of smooth falling.

Penrose is among the scientists calling for the opposite, gravitising quantum mechanics. His twistor theory was devised in an initial attempt. We know gravity as the force that breaks a glass when it slips out of your hand, which is no great shakes, you just pick up the pieces and carry on with your life. But gravity should be thought of as far more immense.

Our galaxy, the Milky Way, is moving through space at a speed of 21-million kilometres an hour due to gravity. It is also rotating, so the sun and its planets are travelling at 828,000km/h around the galactic centre. Seen in space-time we are part of concentric spiral-like movements of immense magnitudes. When galaxies collide with even greater speeds, unimaginable destruction at unimaginable temperatures occurs.

While these don’t affect our daily experience of gravity, when one compares the extra tiny scales at which quantum states occur, and the extreme cold in relative terms they and we need to process information, one can perhaps postulate that quantum mechanics and the sentience it might create are a kind of shelter for hibernation against the universal storm.