In July of 2012, the world was stirred with utter chaos – a chaos of triumph and exaltation. Physicists had finally solved a mystery that had bothered them for over 40 years. While everyone shook each other’s hands fervently, an old man broke into tears. This man was Peter Higgs. His prediction of a new fundamental particle, a necessary addition to the family of fundamental particles in the Standard Model of physics had ultimately been found to be true.
The discovery of the Higgs boson was particularly awaited because it was touted to be the God Particle. But why does it have such a sensational nickname?
The Forces of Nature
If social media has taught us anything, it is that ideas in a culture disseminate at an exponential rate, but so do misinterpretations. Without context, even comedy appears to be tragedy. Had the discovery of the God Particle finally proved that He, in fact, does exist?
If you utter the words ‘God Particle’ while conversing with a physicist, don’t be surprised if he or she retorts with a grimace. To a physicist’s chagrin, the term is now inextricably entangled with the particle. To physicists, it is a needless exaggeration. Peter Higgs rather referred to it as “physics’ most wanted particle”. But why were we so desperate to find it?
The fundamental particles in the Standard Model can be divided into fermions and bosons. Fermions are particles that compose matter, while bosons are the particles that communicate the forces between matter. In the late 1950s, it was confirmed that matter and radiation can exhibit both particle and wave behavior. This is now called the wave-particle duality. Consequently, every particle is associated with a corresponding field or disturbance that the particle “carries”.
For instance, we know that the repulsive and attractive forces between two magnets are electromagnetic, but what you might not know is that this field is carried by photons, its particle analog. While we can detect the field from the movement of the magnets, the same cannot be said about the particles that carry it. This is because force particles or bosons are invisible or ‘virtual’.
The standard model describes three of the four fundamental forces of nature. In order of their strengths, they can be listed as — the strong field that binds the atomic nucleus and is carried by gluons, the electromagnetic field, which is the most commonly encountered and is carried by electrons, and the weak field, which dictates beta decays and nuclear fusion reactions and is carried by the W and Z particles.
A hypothetical particle called the graviton is believed to carry gravity, the fourth fundamental force, but every attempt to incorporate it into the model and complete the puzzle has been unsuccessful. For physicists, the inability to include everyone in a single photograph has been a perennial source of frustration.
The Quest for Symmetry
Physicists desire certainty, they desire the ability to predict so and so and witness so and so unfold. The standard model allows us to describe the behavior of particles one-thousandth the size of an atomic nucleus, but we still aren’t satisfied.
There prevails an obvious asymmetry among the forces. The range of electromagnetism is infinite, but the range of weak force isn’t. Physicists believe that there exists a symmetry, a force that is even more fundamental than all the four fundamental forces. They believe that the four forces are streams of a delta that partitioned from a single river. All the disparate forces are therefore manifestations of a single force, the very first force to spring into existence after the Big Bang.
While gravity is currently out of the question, we hope to achieve symmetry or merge the remaining three forces into a single force we call the Grand Unified Force (GUF). Such a symmetry, however, can only be witnessed at enormous energies or at the Grand Unified Energy – an energy that prevailed moments after the Big Bang. For instance, to detect the GUF, we would require a particle accelerator the size of the Solar System! So, physicists thought the least they could do is try unifying electromagnetism and the weak force into the ‘electroweak’ force. They hoped that perhaps particle accelerators developed in subsequent years would be powerful enough to detect it.
The reason why the weak force isn’t filled with as much wanderlust as electromagnetism is is that, unlike photons, the weak force particles are massive; they grow tired as their mass bogs them down. In the late 60s, Steven Weinberg successfully combined the two theories and devised the electroweak theory. He predicted the W, and for the first time, Z particles, and calculated their masses. 16 years later, CERN detected them successfully and found their masses to be around 100 times that of a proton, which was not too far from what Weinberg originally predicted.
The discovery of the weak force particles was historic, but our work wasn’t yet finished. A complete framework of the electroweak theory could only be developed if one could explain what caused the asymmetry, what caused the masses of the force particles.
The Goddamn Particle
Peter Higgs suggested the existence of a new fundamental force field, an interaction that would imbue mass in the weak field particles. The omnipresent force field eventually came to be known as the Higgs field and the particle associated with it as the Higgs boson. Higgs suggested that the W and Z particles would disturb this field and generate their masses, while photons would swift through indifferently, accruing no mass whatsoever.
To everyone’s surprise, the Higgs field was realized to not just be responsible for the mass of force particles, but also matter particles. Although the mechanisms by which matter would disturb the Higgs field would be different, the implication would be that without the Higgs field, there would be no mass, and without mass, the protons wouldn’t have resisted motion, halted, congregated and formed matter, but instead whizzed through space at the speed of light. Without it, we wouldn’t have existed. So, yes, its discovery was quite important.
Yet, without evidence, a theory is nothing but speculation. The Higgs boson was notoriously elusive; detecting the Higgs field required energies far greater than the prevailing accelerators could offer. Furthermore, greater energies come at greater risks and costs. There was no guarantee that a larger accelerator would detect it. What if all the diligence, the exorbitant expenses and irredeemable time turned out to be worthless?
Twenty long years passed, and physicists were still in the dark. In 1993, American physicist Leon Lederman and Dick Teresi wrote The God Particle: If the Universe is the Answer, What is the Question? Funnily, the original title was supposed to be The Goddman Particle reflecting the overbearing frustration of physicists unable to find it for almost two decades. However, the publisher disagreed, and the writers pruned it to “God”. The result? The name stuck! It stuck like a parasite, and like a conscientious parasite, it seems like it won’t be leaving anytime soon.
Misinterpretations were misinterpreted, and conspiracies ensued. When development of the Large Hadron Collider (LHC) commenced in 2005, bewildering conspiracies were making the rounds. A few people believed that physicists were opening a portal to hell!
Physicists discover new, smaller fundamental particles by examining the debris dispersed in a high-speed particle collision. This is analogous to studying the innards of a television by examining the debris on the ground after it was thrown from the top of a building. In 2012, the LHC — the most powerful particle accelerator humans have ever built – collided protons at nearly the speed of light and finally discovered the long-sought Higgs boson furtively hiding in their viscera.
The discovery of the Higgs field is just the beginning. We speculate that many “versions” of the field will eventually establish not just symmetry, but what is called supersymmetry – an extended standard model that will hopefully fill the gaps that remain. This would also include whatever constitutes dark matter, a field that currently seems to be even more elusive than the Higgs field.
God Particle or not, the discovery is groundbreaking, perhaps one of the most in our short history. Our ancestors set out with sticks, but most importantly, curiosity, following the wet gravel, tracing the blotches to rivulets, climbing precipice after precipice and tracing the rivulets to ponds, which we have now arduously traced to the Four Streams. In this time, we have forged tools which, as Arthur Clarke remarked, are “indistinguishable from magic”. Soon, we will trace the streams to The River, fix our sticks on the ground adjacent to it and reflect on our epic pilgrimage. Then we can cease to wonder “how” and begin to ponder “why”.