By Tejo V, Fall 2020.
When most people think of physicists and physics research, they think of giant telescopes, nuclear reactors, and lasers. As fascinating as all these concepts are, however, there is another field that often remains unregistered by the general public: that of particle physics. Particle physics, otherwise known as high-energy physics, is concerned with the interactions and the properties of elementary particles, that is, particles that cannot be broken down further.
The idea that the universe is made of fundamentally indivisible parts originated in Ancient Greece, typically attributed to Leucippus and Democritus.[1] In the 19th century, John Dalton discovered that matter is indeed composed of small particles called atoms. Of course, it was later shown that atoms were formed of even smaller particles: protons and electrons, for example. However, discoveries didn’t stop there. Throughout the mid-20th century, particle physicists found more and more subatomic particles by colliding them at higher and higher energies, and in the 1970’s, the Standard Model was developed, explaining all of these particles as combinations of a set of 16 elementary particles, grouped into different types like bosons and leptons. Later in 2012, the Large Hadron Collider confirmed the existence of the Higgs boson, the so-called “God particle,” which, put simply, explains why particles have mass.[2] There’s so much fascinating research going on even in modern times. From searches for magnetic particles that have only one pole (in contrast to traditional magnets, which always have a North and South pole), to large-scale experiments attempting to measure the masses of neutrinos,[3][4] modern high energy physics is filled with riveting research.
The field of particle physics nowadays revolves around investigating data from particle accelerators and colliders (hence the moniker of high-energy physics) to confirm existing theories or create new ones. There are many different accelerators in the world, from the Large Hadron Collider built by CERN in Switzerland, the Tevatron located at Fermilab in the US, or the SuperKEKB at the KEK laboratory in Japan. Though there are many different designs and purposes for these accelerators, one thing remains the same: each is a massively expensive, time-consuming project that requires large-scale collaboration. The cost of construction of the LHC was approximately 6.5 billion swiss francs, or about 9 billion USD, and maintenance for each year of operation cost another additional billion – and this is just one accelerator, albeit the most powerful one, out of dozens across the world.[5] An analysis of costs for past particle accelerators conducted in 2014 yielded that the future cost for new colliders will be 7.4-13.4 billion dollars. [6]
The costs of particle physics research, which rests almost primarily on the experiment data from these colliders, are enough to make anyone become skeptical of the benefits. Some suggest that funding for these labs and accelerators, as well as the grants given to particle physicists, could perhaps be better served in medicine, robotics, or even more practical fields of physics. These arguments certainly are not new ones: in 1993, Congress cancelled funding to build the Superconducting Super Collider because of the unjustifiably exorbitant price. [7] Additionally, some claim that it is difficult to say that these titanic machines are necessarily producing meaningful results. The sheer amount of data often creates confusion on how to interpret and judge its significance. However, even when there are meaningful, significant results, some have posed the question of how many people will even learn about it? [8] The esoteric nature of particle physics means that likely only a few people will care enough to seek out this research and understand its value. Is this exorbitant cost at all justified for such a meager return?
Even if you’re confident that modern particle physics research just does not produce any direct benefits, it can be eye-opening to consider the indirect value of particle physics. With direct application to the preservation of life, the accelerator technology in particle physics has proven to be invaluable in medical diagnostic technology in developing PET scans and MRIs, as well as in developing silicon tracking detectors which are being used in neuroscience to understand the retina. Proton therapy is a form of treatment for cancer developed in the 1950’s in Stanford and the UK using accelerator technology that has been used on 30 million patients. Synchrotron light sources are used in protein mapping, and bombarding mercury nuclei with protons produces beams of neutrons that are used in material science. In terms of more daily-life applications, particle physics research has made contributions to magnetic levitation technology through superconducting magnets developed for accelerators, to superconducting cables for low-loss of energy in power transmission, and to computer server technology out of necessity to handle the absurd amount of data coming from colliders. Additionally, perhaps one of the most important inventions of all times, the World Wide Web, the foundation for the internet, was originally developed by a CERN physicist to ease communication among physicists. [9] Seeing all of these innovations, which are certainly not the extent of all technologies developed because of particle physics, it’s difficult not to see the profound impacts that this research has had on the course of human society.
The argument for particle physics just comes down to one key fact that people forget too easily: every aspect of human expertise is interconnected. Stopping research in one field because its immediate results do not seem promising is ultimately self-defeating and hobbles the march of progress. Particle physics involves the most fundamental aspects of the universe and it seems likely that continuing research will likely have a large range of benefits, both in a mundane sense and in the eternal human search for answers. The indirect benefits and the potential for new, absolutely fascinating knowledge make the cost seem paltry in comparison.
[1] Berryman, Sylvia. “Democritus.” Stanford Encyclopedia of Philosophy. Stanford University, December 2, 2016. https://plato.stanford.edu/entries/democritus/.
[2] “Particle Physics.” Particle physics – New World Encyclopedia. Accessed November 15, 2020. https://www.newworldencyclopedia.org/entry/Particle_physics.
[3] Battye, Richard A., and Adam Moss. “Evidence for Massive Neutrinos from Cosmic Microwave Background and Lensing Observations.” Physical Review Letters 112, no. 5 (2014). https://doi.org/10.1103/physrevlett.112.051303.
[4] Gando, A, Gando, Y, Hachiya T, et. al. “Search for Majorana Neutrinos near the Inverted Mass Hierarchy Region with KamLAND-Zen.” Physical Review Letters, August 2016. https://doi.org/10.1103/physrevlett.117.082503.
[5] “LHC Season 2: Facts and Figures.” Geneva: CERN, 2014.
[6] Appell, David. “The Supercollider That Never Was.” Scientific American. Scientific American, October 15, 2013. https://www.scientificamerican.com/article/the-supercollider-that-never-was/.
[7] Shiltsev, V. “A Phenomenological Cost Model for High Energy Particle Accelerators.” Journal of Instrumentation, vol. 9, no. 07, 2014, doi:10.1088/1748-0221/9/07/t07002.
[8] Hossenfelder, Sabine. “The Uncertain Future of Particle Physics.” The New York Times. The New York Times, January 23, 2019. https://www.nytimes.com/2019/01/23/opinion/particle-physics-large-hadron-collider.html.
[9] “Science.” Fermilab, February 9, 2016. https://www.fnal.gov/pub/science/particle-physics/benefits/index.html.