The Atheist’s Guide to Christmas (7 page)

Chapter 13
The Large Hadron Collider: A Scientific Creation Story

B
RIAN
C
OX

The Large Hadron Collider (LHC) at CERN in Geneva is the biggest and most complicated scientific experiment ever attempted. More than 10,000 scientists and engineers from eighty-five countries have built a machine that can re-create the conditions present in the universe less than a billionth of a second after the Big Bang. The reason that the world has come together at CERN in the pursuit of pure knowledge is simple: we want to understand how the world came to be the way it is. This quest has led to a remarkable description of the violence and beauty of the origin of the world, an
d ultimately the emergence of life and civilization in our universe.

Around 13.7 billion years ago, something interesting happened, and our universe began. One ten-million-billion-billion-billion-billionths of a second later, gravity began to separate from the other forces of nature and has remained a weak enigma ever since. After a billion-billion-billion-billionths of a second the universe underwent an exponential expansion, growing from less than the size of an electron to the size of a melon in one-hundred-thousand-billion-billion-billionths of a second. The universe then steadied its growth, and the energy that drove the expansion was transform
ed into subatomic particles, the building blocks of everything in the universe. Around a million-millionths of a second after the interesting event, something known as the Higgs field began to behave in an unusual way. This caused most of the subatomic particles to acquire mass, and there was substance in the universe for the first time. From this point onward, we are reasonably sure that our story is correct because over the past century the LHC’s smaller cousins have explored these violent conditions in exquisite detail. We are therefore the first culture in history to engage in a program to te
st our creation story experimentally. The primary job of the LHC is to explore the story during the time when the Higgs field became influential.

The LHC is a 27-kilometer-long circular machine that accelerates subatomic particles called protons to as close to the speed of light as is possible with our current technology. Approximately half of your body
is made up of protons; the other half is made of neutrons. The machine straddles the border between Switzerland and France, which the protons cross 22,000 times every second inside two parallel drainpipe-size tubes. More than 1,600 powerful electromagnets, operating at –271 degrees Celsius, keep the protons spiraling neatly around the machine in precisely controlled orbits. The tubes cross at four points around the ring, allowing up to 600 million protons to smash into each other every second at each point. Surrounding these mini-explosions are four detectors: digital cameras sit
ting inside cathedral-size caverns 100 meters below the vineyards and farms. It is their job to photograph the stage in our creation story that we want to explore.

According to theory, the Higgs field acts like cosmic treacle. The subatomic particles that make up our bodies and everything we can touch in our world acquire their masses by interacting with this all-pervasive stuff. Imagine attaching a string to a ping-pong ball and pulling it through a jar of thick treacle. If you didn’t know better, you might conclude that the ping-pong ball was very massive because it feels difficult to move. This is roughly how the Higgs field works in our best theory of the subatomic world, known as the standard model of particle physics. It may sound
far-fetched, but the Higgs model has survived for more than forty years without actually being shown to be correct because it has very elegant mathematical properties that physicists find convincing.

With the LHC, however, D-day has arrived for the Higgs model. If it is correct, then particles associated with the Higgs field, known as Higgs particles, must show themselves in the LHC’s underground detectors. We can be so sure because, to do the job necessary in our creation story, the Higgs particles must be light enough for the LHC to create them in its high-energy proton collisions. If the Higgs particles don’t show up, then nature must have chosen some other mechanism to generate mass in the universe, and we will observe that instead. It’s as if the LHC allows us to journey back in
time to the point in our story where mass appears in the universe for the first time and take pictures of this most important of historical events. Because we can repeat the collisions billions of times, we can carry out very high-precision measurements that will allow us to investigate our creation story scientifically.

This time in the universe’s evolution is known as the electroweak era, because two of the four forces of nature, the familiar electromagnetic force and the less familiar weak nuclear force, reveal themselves as different facets of a single unified force at these temperatures. The weak nuclear force is shielded from our everyday experience deep within the atomic nucleus, but it is vital in allowing the sun to shine because it allows protons to change into neutrons, and therefore hydrogen to fuse into helium with the release of sunlight. The LHC will probe
this unification, which intimately involves the Higgs mechanism, with unprecedented precision and verify or refute our current theoretical models.

There are also hints that there may be surprises in store. Some particle physicists believe that the standard model Higgs theory is flawed because it requires a very delicate fine-tuning of parameters to make it work. Fine-tuning is considered ugly in physics; if the universe only works if the strengths of the forces or the masses of particles take on very precise values, then physicists naturally want to know why this should be so. Coincidences do happen, but it is wise to look for more elegant explanations. There is a popular alternative to the standard model that goes by the nam
e of the minimally supersymmetric standard model, or MSSM. This theory requires a doubling of the number of fundamental particles in the universe, plus no fewer than five different Higgs particles.

This sounds like additional complexity rather than an elegant simplification, but the MSSM achieves more than solving some of the fine-tuning problems: it also provides a possible answer to a decades-old problem in astronomy. It has been known for some time that there is much more matter in the universe than can be accounted for by simply counting up the number of stars and galaxies that we can see. In fact, it appears that five times as much matter is required to explain the orbits of stars around galaxies and the motions of large clusters of galaxies through the universe. Models
of this missing stuff, known as dark matter, work best if the missing matter takes the form of an as yet undiscovered heavy subatomic particle. Within the MSSM, such a particle does exist, and if the model is correct, then this particle and a whole new zoo of its sisters should show up at the LHC. Such a discovery would represent a giant leap in our understanding of the subatomic world and the evolution of the universe as a whole.

From this point onward, we move into the realm of the scientifically well tested, and our story can be told with more certainty thanks to the generations of particle accelerators that went before the LHC and decades of study in nuclear physics, cosmology, and astronomy. After a millionth of a second, the four forces of nature had taken on the separate identities we see today, allowing a sea of particles called quarks and leptons to interact in a dense subatomic soup. After a second or so, the universe was cool enough for the quarks to stick together into protons and neutrons, and p
articles called neutrinos were freed from the soup to roam through the universe forever. There are several hundred of these primordial relic neutrinos in every square centimeter of space today, including the space inside your body. Three minutes passed, and protons and neutrons began to form simple chemical elements. In less than half
an hour, the universe’s supply of hydrogen and helium was fixed in the ratio we see today: 75 percent hydrogen to 25 percent helium.

For another 380,000 years the universe was too hot and dense for light to travel through, but as it continued to expand it reached transparency and the photons from the violence of the early years were set free. We can detect these photons today as an ever-present visual hiss known as the cosmic microwave background—a fossilized picture of the early life of our universe.

The universe remained locked in a cosmic dark age until the weak but ever-present force of gravity began to cause clouds of primordial hydrogen and helium to collapse, forming the first generation of stars. These stars fused hydrogen into helium and, in a complex dance between the strong and weak nuclear forces and electromagnetism that relies on an incredibly delicate balance between their relative strengths, helium stuck together into longer chains; three helium nuclei glued together make carbon, the element of life. As the first generation of stars ran out of fuel, they exploded
, scattering the newly formed carbon, oxygen, and other light elements into the universe. During the explosion itself, gold, silver, and the heavy elements were made.

The interstellar clouds, now enriched with the building blocks of life, collapsed again under the inexorable influence of gravity to form stars with dense, rocky planets orbiting around them. On at least one of these planets, the newly minted elements got together to form complex structures capable of self-reproduction, and the universe sprang into life. On this precious world, single-celled organisms began to cooperate in colonies that, given billions of years of relative stability on the surface of the planet, worked out how to journey through space and, in the year they arbitrar
ily called 1969, left the imprint of a structure they called a foot on another world.

There are those who argue that science removes the majesty from the universe by demystifying it. My reply is that the scientific creation story has even more going for it than the virtue that it is most likely correct, at least in its broad sweep. It teaches us that we are part of nature, built of the same stuff as stars, planets, asteroids, and comets. Our protons and neutrons have been around since the earliest times, glued together into heavy elements in the nuclear furnaces of long-dead ancient suns, blasted out into the universe and resculpted from diffuse interstellar dust cl
ouds by the gentle hand of gravity. We are colonies of particles that have learned to think; every human is a grand natural structure, an emergent form permitted to exist by the laws of nature and realized by a stream of coincidence and causality. When the pattern of atoms known as you ceases to be, the building blocks will return to the voids of space, and in a billion years or more they may take their place in anot
her structure so beautiful that a future mind may perceive it to be the work of a god.

The scientific creation story has majesty, power, and beauty, and is infused with a powerful message capable of lifting our spirits in a way that its multitudinous supernatural counterparts are incapable of matching. It teaches us that we are the products of 13.7 billion years of cosmic evolution and the mechanism by which meaning entered the universe, if only for a fleeting moment in time. Because the universe means something to me, and the fact that we are all agglomerations of quarks and electrons in a complex and fragile pattern that can perceive the beauty of the universe with
visceral wonder is, I think, a thought worth raising a glass to this Christmas.

Chapter 14
How to Understand Christmas: A Scientific Overview

N
ICK
D
OODY

“Christmas”—it’s one of those words we bandy about confidently every day. “Happy Christmas!” we shout at children in the street. We send cards inviting friends to “come Christmas with me.” Anyone lucky enough to find himself in Cardiff on February 29 has surely joined in with the chorus of “A-Christmassing Down the Mound.” But could any of us truly say what the word means? Tests have suggested that we could not.
⁴

The scientific history of Christmasology is a rich and fascinating one. My purpose here is to give an overview accessible to the layman, but not so simplified as to misrepresent the true story. As ever, it is impossible to please everyone, so I shall take the opportunity to apologize to readers hoping for an in-depth explanation of Barsky’s chimney hypothesis; there simply wasn’t room. Conversely, if newcomers to the field find themselves unfamiliar with terms like
Sado-Melchiorism
or
tree
, I hope that they will forgive me, and make use of the bibliography to dig deeper into this fascinating
seam of study.

The Christmas story with which most of us are familiar begins in 1858, in Berlin, where a young philologist and psychologist, Bernhard Gernhard, began to question whether we all meant the same thing when we said “Christmas” (the story that his brainwave came in a dream as he slept on a stuffed reindeer is an entertaining one for children, but probably apocryphal). The thrust of Gernhard’s initial train of enquiry was as follows:

We all accept that certain things are Christmassier than others.

We largely agree on what those things are.

Therefore, he reasoned:

We should be able to quantify “Christmassiness,” because Christmassy things should have it in common.

To modern Christmasologists, Gernhard’s initial experiments might seem amusingly naive, but they are also recognized as germane to the discipline as a whole, and without him the twenty-first-century world would look very different. The North Pole, for example, would st
ill be a barren, frozen wasteland without the magnificent Yule Hypercollider we take for granted today.

As so often, we learn more from Gernhard’s failures than his successes. Almost everything we know about the Christmassiness of beards, for example, can be traced to his experiments in the spring of 1860. Before then, it was generally considered that beards themselves had a Christmassy quality when viewed from the lap of the beard’s owner. Gernhard had no initial reason to dissent from this view, but his attempts to measure
Bartweihnachtheit
threw up some interesting and unexpected problems.

Gerhard’s first experiments involved placing a child at varying distances from the lap of a bearded man and noting how Christmassy the child reported feeling.
⁵
Naturally, he expected Christmassiness to increase with proximity; the point of the experiment was to find by how much. What no one could have expected, though, was that some of the children, even placed directly on to the lap of a bearded man, didn’t feel Christmassy at all.

Gernhard was dumbfounded. He recalibrated his experiments, double-checked the quality of his children,
⁶
and tried again, first approaching the bearded men’s laps at a painfully gradual pace, next practically firing the children at the laps. Still some of the children reported no Christmas. Gernhard’s quest seemed to be at a dead end.

It was three weeks before it dawned on Gernhard that the fault might not be with the children. He was putting together a new team of bearded men
⁷
when it suddenly occurred to him: what if not all beards are Christmassy? Some quick thought experiments convinced him that he was on to something: it had been assumed by the Greeks that, say, a sea urchin with a beard isn’t Christmassy because the un-Christmassy nature of the sea urchin cancels out the Christmassiness of the beard. But no one had ever considered that some beards might not be Christmassy at all! No one had ever before attempted to ima
gine something potentially Christmassy with a non-Christmassy beard. Before 1860, such a thing was literally unimaginable. Close your eyes for a moment and picture yourself being given a plate of sprouts by a female horse with a blue beard,
⁸
and you might come close to understanding Gernhard’s excitement.

Over the next eight years, Gernhard’s experiments refined and expanded his theories, and in 1868 he published his collected observations in
On the Christmassiness of Beards
—a true milestone in science, famously referred to by Mark Twain as “a Christmas
Origin of Species
.”
⁹
It won him a place in history and the inaugural Templeton Peck Award for Christmas Science.

What Gernhard had achieved was a complete shift in the scientific consensus, akin to the Chomskyan revolution in linguistics o
r the Wang theory of bendy numbers. Christmassiness was no longer seen as an essential quality pertaining to an object, but understood as the subtle function of a series of variables.
On the Christmassiness of Beards
not only taught us that white beards are more Christmassy than black ones, but also that this Christmassiness can be decreased by the addition of sunglasses or Chineseness, or increased by jolliness or sitting in a cave.
¹⁰
Not for nothing is the nineteenth century known as the Christmas century. From being a sideline interest, the pursuit of a few moneyed eccentrics, Christmasology now t
ook its rightful place as a “proper” scientific discipline, sitting proudly alongside biology, space physics, and clapometry.

One might be forgiven for thinking that Christmasology took a backseat to war in the first half of the twentieth century, but on at least one occasion in 1914, the opposite is true, when soldiers in the trenches ceased fire so that keen amateurs on both sides could examine a Christmas that had landed in no-man’s-land. Still, war and its aftermath took its toll, and when the Second World War began, making hideous sense of the name of the First World War, many Christmasologists were put to work cracking the Enigma code or helping build the atomic bomb.

The second half of the twentieth century saw Christmasology explode as a discipline, diversifying into subfields like Geochristmasology and Medicochristmasology,
¹¹
and even sub-subfields like Dermachristmasology.
¹²
Of these, perhaps the most interesting from the historical point of view is Christmasozoology.

Huge strides have been made in the past fifty years in understanding the intricate relationship between Christmas and nature. Barsky’s chimney hypothesis (
BCH
), too complex and difficult to go into here, or indeed anywhere, proved the missing piece of the puzzle when it came to discovering the evolutionary advantages gained by reindeer that spend part of the year on roofs. For his integration of
BCH
into reindeer game theory, Christmasomathematician George Maynard Carol was rightly awarded 1968’s Templeton Peck Award.

Even more exciting were the discoveries of the 1970s, still kno
wn as the Christmas decade. By now it was accepted that Christm
as occurred in nature, and that certain animals (reindeer, camels, oxen—especi
ally with assen) are naturally more Christmassy than others (sh
arks, minotaurs, robots).
¹³
But in 1974, Carol George and her husband, George, showed that it was possible to intervene and artificially elevate the Christmassiness of an animal.

The Maynard effect, as it is now known (Carol called it after her middle name), is observed if one compares a robin with some mice. Robins, as is well known, have an unusually high level of natural Yule—far higher than a mouse. In fact, even a hundred mice are not as Christmassy as a single robin. What the Georges demonstrated,
though, is that you can approach robin-like Yule levels with only about fourteen mice by dressing them in tiny waistcoats.

The Georges’ work was greeted with interest but did not, at first, overwhelm. For one thing, they were still measuring Yule levels with the modernized Gernhard method—essentially, asking children how Christmassy the test subject made them feel, then adjusting statistically for orphans. This was no indictment of their experiments; the MG method was the best available at the time, but it made the scientific community reluctant to greet new Christmas research with anything but a cautious welcome.

Then, in 1978, something incredible happened: Donald Maygeorge invented the Christmasometer.

Maygeorge, a naval engineer by background with only a layman’s knowledge of Christmasology, was tinkering about with some naval tinsel in his shed one dull 1978 afternoon when an idea suddenly hit him. And it was an idea that, had he been named Newton, would have made him the second most famous Newton
¹⁴
in science.
¹⁵

What Maygeorge suddenly realized, and what no one else had thought of, was breathtakingly simple: by taking a Van Rijd detector (the main component of a clapometer), isolating its feedback loop, and replacing the Fenchurch plate with a Bethlehem coil,
¹⁶
you suddenly have a Van Rijd detector that works with tinsel instead of compère’s rouge, and uses the tinsel to boost its own output wave as a square of the tinsel’s Yule levels. A child could have thought of it! Suddenly we lived in a world that had a way of measuring Christmas. Aristotle had been right after all.

From that spring in 1978—still known as the year of Christmas—the whole realm of Christmasology had changed. Not only was there now an accurate way of measuring Christmas, but another implication soon dawned on the Christmas world. The Sezniak hypothesis had to all intents and purposes been proved: there must be a Christmas particle.

More than thirty years on, we know more about Christmas than ou
r ancestors ever dreamed possible. We have identified the Chris
tmassiest color in the spectrum;
¹⁷
we know which is the most Christmassy pla
net in the solar system (it’s Earth);
¹⁸
our computers have calculated the human name most redolent of Christmas;
¹⁹
and anyone can tell a genuine caroler from a singing mugger or “wassailant” at the flick of a switch. But do we really understand what we mean when we say “Christmas”? As I indicated before, it appears not.
²⁰
But we shall soon.

The last step on this remarkable journey must be the Christmas particle. The Sezniak yulion is the final part of the puzzle that began with Gernhard’s naive beard work. Once the particle is identified, the Christmas mystery will be solved. The quantum event triggered by putting a waistcoat on a mouse, a scarf round an obelisk of
snow, or a white beard on a fat, laughing man will at long last be understood. Man will be able to look the robin in the eye and say, truthfully, “I know you.”

The Yule Hypercollider, to be activated at the North Pole in just a few short weeks (at the time of writing), is the key to this final step. Those who understand Christmas rather better than the hysterical doom-mongers have, thankfully, overruled early objections that it might destroy the world. Some of the technical difficulties, such as the disembodied, screaming voices, the mysterious faces in the sky, or the strange behavior of animals,
²¹
have delayed but mercifully not stopped the hypercollider’s progress, and I hope you will join with me and with all mankind on December 25 as
we look north with bated breath and wonder in awe as the Christmas story finally comes to an end.