Is the cost of high-energy laboratories justified

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PHYSICAL SCIENCE

Is the cost of high-energy laboratories justified?

Viewpoint: Yes, research in the area of high-energy physics has already led to numerous advances that have provided great public benefit, and the search for the ultimate building blocks of the universe is a fundamental part of human nature and an expression of human civilization.

Viewpoint: No, the enormous public money spent on high-energy laboratories would be better spent on scientific work with more relevance and clear applications.

The field of particle physics revolves around finding a simple, orderly pattern to the behavior of atomic and subatomic matter. Among its tools are particle accelerators that act like giant microscopes, peering into the atom, past electrons and into the proton-and neutron-populated nuclear core.

The modern view of the structure of matter is based upon thousands of experiments that showed over time how all matter could be broken into particles called atoms. More than 100 kinds of atoms occur in nature and combine to make simple molecules like water (H 2 O—two hydrogen atoms, one oxygen atom) or complex million-atom molecules like DNA (deoxyribonucleic acid), the building block of life on Earth.

An atom is mainly empty space, occupied by cloudlike swarms of electrons, each with a tiny negative electrical charge. The atom's core—the nucleus—is 100,000 times smaller than the atom and is composed of neutrons and protons. To see the nucleus takes particle accelerators—devices in which charged particles are accelerated to extremely high speeds—that push the limits of microscopic sight.

In the 1950s and 1960s, new, powerful accelerators smashed atomic particles together at increasingly higher energies, producing a gaggle of new particles. Experiments in the 1970s showed that protons and neutrons were not the fundamental, indivisible particles physicists thought—instead they were made of smaller, pointlike particles called quarks. Quarks come in flavors (or kinds) that signify their symmetry properties, and with three strong charges called colors. The universe itself, in its early stages, existed as a soup of quarks and leptons (both fundamental kinds of particles). According to a theory called the Standard Model, there are 12 fundamental particle types and their antiparticles. In addition, there are gluons, photons, and W and Z bosons, the force-carrier particles responsible for strong, electromagnetic, and weak interactions. The Standard Model was the triumph of 1970s particle physics and is now a well-established theory that applies over a range of conditions. Today, experiments in particle physics seek to extend the Standard Model in order to discover what has been called the Theory of Everything—the grand unification of many theories into an ultimate theory of how the universe works.

Those who say the cost of high-energy labs is justified base their belief on extraordinary spinoffs from particle physics research—advances in cancer treatment, medical scanners, nuclear waste transmutation, microchip manufacturing techniques, and other industrial applications—and on the notion that the search for the ultimate building blocks of the universe is a fundamental part of human nature and an expression of human civilization.

Atomic and subatomic physics research has led to many useful and important innovations. The renowned English physicist J. J. Thomson discovered the electron in 1897 by using a very simple kind of particle accelerator—a cathode-ray tube. Today cathode-ray tubes are the basic component of television screens, computer monitors, and medical and scientific instruments. Using a basic particle beam, English physicist Ernest Rutherford, often referred to as the founder of nuclear physics, revealed the nature of the atom and ushered in the atomic age. The quest to understand the atom led to a major scientific revolution in the 1920s—a new understanding of nature in the form of quantum theory. And this led to laser technology, solar cells, and electronic transistors—the basis of modern electronics. In the 1930s, American physicist E. O. Lawrence created the first working circular particle accelerator (cyclotron) and used it to produce radioactive isotopes for cancer treatment. Accelerated beams of neutrons, protons, and electrons have been used to treat cancer in thousands of hospitals. Computed tomography (CT scan) owes its development to particle detection methods used in high-energy physics. Positron emission tomography (PET scan) uses components developed in particle physics research. Magnetic resonance imaging's (MRI) noninvasive diagnostics is a particle physics spin-off.

Even research problems—like synchrotron radiation—have led to useful applications. Tools that use synchrotron radiation now are used in medical imaging, environmental science, materials science and engineering, surface chemistry, biotechnology, and advanced microchip manufacturing.

High-energy accelerators allowed more accurate measurements of the particles that make up the atomic nucleus. In the process, new theories of the nature and structure of the matter were developed and tested, leading to a better understanding of the origin and evolution of the universe.

Technical knowledge gained in scientific research is also used in broader research and development. Vacuum technology, developed for accelerators, has many commercial uses. Superconducting magnets are being developed for commercial use in power transmission, energy storage, conservation, medicine, and high-speed magnetically levitated trains called maglevs—literally "flying trains" that use magnets chilled in helium to a achieve a superconducting state.

The most practical development of high-energy physics was the World Wide Web, created by CERN, the European high-energy physics lab, as a way for high-energy physicists to exchange information. It transformed information sharing and revolutionized communications. It did no less than change the world, making possible many collaborations in science, medicine, entertainment, and business.

Scientific research may seem removed from everyday life, but in the long term esoteric knowledge often enters the mainstream with startling consequences.

Those who cannot justify the cost of high-energy labs claim that even though budgets for high-energy physics experiments can run into the billions of dollars, physicists never know exactly what they will discover about the nature and behavior of matter or how the knowledge will pay off. Public money invested in such experiments, opponents argue, would be better spent on scientific work with more relevance and clear applications, like medical research, programs that directly improve people's lives, research that leads to feeding the world's population, and research into energy alternatives for nonrenewable resources. Private funding, some say, might be a better way to pay for particle physics experiments.

One example is the Superconducting Supercollider (SSC), an $8 billion paticle accelerator proposed to be built in Texas in the late 1980s and early 1990s. Congress canceled the SSC in 1993 after legislators refused to continue funding the project. Because the SSC caused such controversy, cost so much money, and changed the course of science funding, one physicist called it the "Vietnam of physics." In 1993 critics argued that no high-energy lab project could stick to its budget. The price of particle physics research remains high, with duplicated efforts in several labs in the United States and Europe.

Particle physics scientists are still unable to explain the relevance of and applications for their work when asked why their projects should be publicly funded. Their best argument for doing the research is that if the United States does not fund the expensive projects, the country will not be in a position of leadership in the field. Americans should not worry about not being at the forefront of particle physics. Once the knowledge is gained—whether in Europe, Asia, or North America—it can be applied anywhere.

Medical research has an impact on everyday life. It is unlikely that any knowledge from high-energy physics will have a clear impact on the wealth and health of Americans.

—CHERYL PELLERIN

Viewpoint: Yes, research in the area of high-energy physics has already led to numerous advances that have provided great public benefit, and the search for the ultimate building blocks of the universe is a fundamental part of human nature and an expression of human civilization.

Billions of dollars each year are spent around the world on the continuing investigation into the structure of matter, funding giant particle accelerators and international research groups. Some have questioned the value of such research, which they see as esoteric and of little use to the average person. However, research into high-energy physics has had many extraordinary spin-offs in the last century, including cancer treatment, medical scanners, nuclear waste transmutation, microchip manufacturing techniques, and other industrial applications. Aside from the obvious material benefits it can also be argued that the search for the ultimate building blocks of the universe is a fundamental part of human nature and an expression of human civilization. Perhaps a better question is whether high-energy physics is receiving enough funding considering its proven practical value and its potential to unlock the secrets of the structure of the universe.

New Tools for Human Development

Scientific innovation and research is an important aspect of modern life. The world we live in has been revolutionized by technological and scientific breakthroughs time and time again. Innovation in one field can have great impact in other seemingly unrelated areas, and it can change the way we think about, and interact with, the universe itself. Developments in time-keeping led to better sea navigation, materials developed for spacecraft led to nonstick cook-ware, and research into the components of the atom has given us a host of medical and industrial machines. Time and time again seemingly esoteric scientific research has provided new tools for human development. Basic scientific research always seems to pay off in the long term, giving back far more than it consumes in terms of resources.

Yet the value and utility of pure scientific research is often questioned on grounds of cost. In a world that cries out for more food, more medicine, more everything, can we afford to spend billions of dollars on research that appears to have no practical values or goals? The study of particle physics is often singled out by would-be cost cutters. It is an expensive field of study, using gigantic accelerators that can be many miles in length. Inside these devices small highly focused bundles of particles are sped up to near the speed of light and then aimed at particle targets. The subatomic debris from the moment of collision is then studied. Accelerators are costly to build, to maintain, and to run, and high-energy physics is often regarded as a field that does not offer useful applications, yet nothing could be further from the truth.

Applications of High-Energy Physics

Research into atomic and subatomic physics has already led to many useful and important innovations, as well as giving us a clearer picture of the nature of reality and the building blocks of the universe. The discovery of the electron, by J. J. Thomson in 1897, was made using a very simple kind of particle accelerator, a cathode-ray tube. The cathode-ray tube was an important early tool for probing the structure of the atom, and over the years it was improved on, refined, and modified. Today the cathode-ray tube is the fundamental component of television screens, computer monitors, and medical and scientific instruments.

Using a basic particle beam, Ernest Rutherford revealed the unexpected nature of the atom, a tiny compact nucleus surrounded by an insubstantial cloud of electrons. His discovery was to have unforeseen consequences. "Anyone who expects a source of power from the transformation of these atoms is talking moonshine," said Rutherford, yet his discovery ushered in the atomic age. Although human foibles and flaws led some to use the power within atoms for destruction, it has also become a valuable source of power. And although nuclear fission has unwanted products and problems, the hope is that soon nuclear fusion will usher in an age of safe and plentiful energy.

Using Quantum Physics

The quest to understand the atom led to a major scientific revolution in the 1920s. A tide of experimental results cast doubt on the underlying principles of classical physics and gave rise to a new understanding of nature in the form of quantum theory. Understanding of the quantum reality of the universe has led to laser technology, solar cells, and the discovery of the electronic transistor, which underlies all of modern electronics. Quantum theory may seem unreal or contrary to common sense, but all around us are devices that rely on quantum effects and have become integral parts of our lives.

Many other practical benefits have been discovered in the process of exploring the subatomic particles and forces that shape the physical universe. In the 1930s, the first working circular particle accelerator (cyclotron) was used by its creator, E. O. Lawrence, to produce radioactive isotopes for cancer treatment. After the day's physics experiments had been run, Lawrence would keep the device on through the night in order to produce isotopes for local California hospitals. Since then there have been many developments in the use of accelerators for medical use. Accelerated beams of neutrons, protons, or electrons have been used to treat cancer successfully in thousands of hospitals worldwide. The CT scan (computed tomography) owes its development to particle detection methods used in high-energy physics. The PET scan (positron emission tomography) is yet another medical machine that contains components initially developed in particle physics research. The MRI (magnetic resonance imaging) is also a spin-off from particle physics research that gives doctors a powerful diagnostic tool for noninvasive imaging of the body. The MRI relies on the esoteric quantum property of "spin" in the atomic nucleus and the discovery by chemists that the energy associated with the flip of this spin depends on the chemical environment of the nucleus.

Even the problems that have beset researchers of high-energy physics have led to useful applications. Accelerated charged particles lose energy as they travel, in the form of light. This problematic phenomenon, called synchrotron radiation, is one of the reasons why accelerating particles requires so much power and such large-scale constructions. However, although synchrotron radiation makes research into particle physics more difficult, it has been harnessed as a source of useful radiation. Tools using synchrotron radiation are used in medical imaging, environmental science, materials science and engineering, surface chemistry, biotechnology, and the manufacture of advanced microchips. The scientific uses of synchrotron radiation include research into hemoglobin (the oxygen carrier in blood), and it has been important in the quest to find a cure for ALS (Lou Gehrig's disease) and the AIDS virus.

High-energy accelerators allowed for more accurate measurements of the size of the particles that make up the nucleus of the atom, the neutron and the proton. However, they also revealed the unexpected result that these particles are themselves made from yet smaller particles. The strangeness of the subatomic world of quarks was discovered, and as particle accelerators have improved and developed, more and more has been revealed about the internal structure of what were once considered elementary particles. Six quarks have been found and a host of other subatomic particles. In the process new theories of the nature and structure of the matter have been created and tested, and a better understanding of the origin and development of the universe has been gained.

Commercial Uses

In order to build more powerful accelerators to probe ever deeper into the subatomic world, great leaps in technology and engineering have been made. The technical knowledge gained in the name of pure scientific research has then been used in broader research and development. Sophisticated vacuum technology, developed for accelerators, has found many commercial uses. The boundaries of superconducting magnet technology have been pushed by high-energy physics research, and such technology is now being developed for commercial use in power transmission, energy storage, conservation, medicine, and high-speed magnetically levitated trains (maglevs).

The people who build, maintain, and use the huge accelerators of high-energy physics gain valuable knowledge that has application beyond particle physics. Many of the medical and industrial tools mentioned here were designed and built by people trained in the research environment but who moved into the commercial workplace. Only one in five Ph.D. students in the field of high-energy physics remains in basic research. Many of the others go into industrial research and development.

High-energy physics is a field rich in international collaboration. Many countries share information, reproduce and confirm experimental results, and share the costs involved. This collaboration led to one of the most unexpected practical developments of high-energy physics: the origin of the World Wide Web. The Web was created by the European high-energy physics laboratory CERN as a tool to enable high-energy physicists to exchange information instantaneously and make collaborations among them easier. The Web has unexpectedly grown to include millions of users and a new global economy. It has transformed information sharing and has revolutionized how we communicate and the way we view the world and its people. It has also enabled many other collaborations in science, medicine, entertainment, and business.

Conclusion

Although a few billion dollars a year for scientific research may seem like a huge amount of money, in the larger scheme of things it is a small price to pay. The benefits that society has already gained from basic research are so enormous as to be incalculable. High-energy physics is just one field that competes for the few billions of public funding given to science, but it is one of the more expensive. The costs of running a single high-energy complex can be over $300 million a year, and construction costs can be even larger. However, compared to the trillions the world spends on military weapons and the vast fortunes accumulated by companies and individuals in business, the money spent on scientific research is far more beneficial to humankind. Opponents of scientific funding may argue that the money could be spent to help feed the starving or house the homeless, but it must be asked how many more people would be starving or homeless (or worse) if not for the benefits basic research has given the world. Indeed, given the track record of pure scientific research to improve the human condition and the possible benefits that may come from such research, we should ask whether science receives enough public funding around the world.

An American politician questioning the funding of high-energy physics once said, "We've got enough quarks already. What do we need another one for?" Indeed, the discovery of quarks has no obvious benefits to the average person and will not in itself make the world a better place to live in. However, the knowledge gained in studying particle physics does help make the universe a more understandable place. High-energy physics helps us understand how the universe is constructed and how it works. That in itself is a goal worth pursuing. It is part of the human condition to seek answers about ourselves and the universe we live in.

The search for the fundamental truth about the nature of nature has led to many important and valuable discoveries over the millennia that humans have pondered such questions. Many tools and products we take for granted today, in medicine, telecommunications, and in the home, owe their existence to the pure science research of the past. In the future the secrets unlocked inside particle accelerators may lead to many different applications and new fields of technology that are as yet undreamed of.

Research into high-energy physics has led to many concrete benefits, from medical scanners and treatments, to industrial superconductivity technology, and even the World Wide Web. History has shown us that although much pure scientific research may seem wholly removed from everyday life, in the longterm esoteric knowledge often enters the mainstream with startling consequences. High-energy physics is the quest to understand the fundamental building blocks of nature and how they fit together. The knowledge we have gained has already given the world a variety of important discoveries and in the process many unexpected benefits and tools. Although we have little idea at present what particular advances further basic research will give us, we have every historical reason to expect that the benefits will greatly outweigh our investment.

—DAVID TULLOCH

Viewpoint: No, the enormous public money spent on high-energy laboratories would be better spent on scientific work with more relevance and clear applications.

When physicists work in high-energy laboratories doing experiments in elementary particle physics, they use powerful and expensive equipment to learn more about the universe and, in particular, to gain better understandings of matter and its behavior in its smallest form. Some experiments in particle physics look at matter as small as a billionth of a billionth of a meter (one meter is approximately 39.37 inches). This requires producing particle beams at the highest possible energies and the use of very expensive equipment. The most costly aspects of their experimental equipment is the accelerator, the complex of high-energy magnets and the construction of underground tunnels—miles in length—in which the experiments take place. An accelerator is like a super microscope (although miles long) designed to afford physicists their closest look at matter in its subatomic state.

Overpriced and Unpredictable Research

Although the goals of high-energy lab experiments are clear, the practical applications of the information physicists might discover are not. Budgets for high-energy labs run into the billions of dollars, but physicists do not know exactly what they will discover about the nature and behavior of matter in such small forms. They do not know how that knowledge will pay off. They cannot even predict how this knowledge will be relevant to our world, nor can they predict how this knowledge will benefit humankind. For example, physicists who work with expensive accelerators hope to find Higgs boson—a particle that is extremely small with no mass of its own, yet it gives matter its mass. Billions of dollars are being spent in search of Higgs boson, with no indication that it will be found.

Because of the great expense associated with high-energy labs and the lack of relevance and direct application of knowledge that will be gained from high-energy lab experiments, these labs are not worth the expense. If public money is to be invested in such experiments, that money would be better spent on scientific work with more relevance and clear application, such as medical research, programs to directly improve people's lives, research that leads to feeding the world's population, and seeking energy alternatives of the earth's nonrenewable resources.

Private funding may be a better way to foot the bill for elementary particle physics experiments. Private funding gives scientists more freedom from legislators politicizing their work, and it also provides a smoother vehicle for making commercial use of their finds through patents.

SSC Controversy

To better explain why high-energy labs are not a prudent expenditure of science dollars drawn from taxpayers and how high-energy experiments carried out at public expense become political footballs, we must go back not too far into the history books—to the early 1990s—and look at the experience with the Superconducting Supercollider (SSC). The SSC project was a particle collider, an "atom smasher" of sorts, aimed at finding a better understanding of matter. As mentioned earlier, accelerators are very expensive and SSC was no exception. Its budget was $8 billion, and, had it been completed, it was certain to go way over budget.

The U.S. Congress canceled SSC in 1993 after legislators refused to continue funding the project. It has always been difficult for physicists to explain the value of such research to humanity and justify the spending in terms of direct benefits, and legislators perhaps feared a public backlash from the expenditure, although the economy was strong in the early 1990s.

Because the SSC caused so much controversy, cost so much money, and became a political quagmire that changed the course of science funding, it has been called "the Vietnam of the physics world" by one physicist.

For example, an August 1992 article in Physics Today , a magazine that serves the physics community, was entitled "What's Gone Wrong with the SSC? It's Political, Not Technological." The best argument for private funding for expensive science is that the work cannot be so easily politicized. SSC became even more politicized when some Texas politicians rallied behind the project. With SSC based in Texas, they felt it was good for Texas. Politicians from other states were less willing to keep the dollars coming. One of the more outspoken congressional foes of SSC back in 1992 was Dale Bumpers (DArk.), who used the argument that SSC was irrelevant research.

Once more, critics including Bumpers argued in 1993—and it is still true—that no high-energy lab project can stick to its budget. The Department of Energy, they said, cannot control "cost overruns." Exceeding a budget is an increasing and unwelcome burden on taxpayers.

Work Abroad

Since 1993 other accelerator projects started, however, and many American physicists began working abroad, still attempting to unravel the secrets of matter. The price of this work remains high with duplicated efforts spread out through several labs in the United States and in Europe.

At SLAC (Stanford Linear Accelerator Center), at the CERN lab in Geneva, Switzerland, and at the Fermilab National Accelerator Lab in Chicago, scientists are working with accelerators. At CERN, scientists are constructing the Large Hadron Collider (LHC) with a $6 billion price tag. The Fermilab collider is the highest energy collider in the world—for now—but will be surpassed over the next few years when the European-based CERN LHC starts producing data.

Many physicists are concerned that the United States won't contribute. "The U.S. won't be at the energy frontier then," lamented Johns Hopkins University physicist Jonathan Bagger, professor and co-chair of a U.S. Department of Defense and National Science Foundation subpanel. "Do we want to host another facility at the energy frontier, or is our country content with sending our physicists abroad to use there facilities elsewhere?" Bagger added, "We are going through a cyclic period of reassessment of our goals and long-term plans in high-energy physics."

"Reassessment" means thinking about new accelerator projects. New efforts have always been on the drawing board since the demise of SSC, and physicists are lobbying to begin anew. For example, in July 2001, physicists from around the world met at Snowmass, Colorado, to discuss the future of particle physics and seek international cooperation on a $6 billion 20-mile-long new particle accelerator so large, so powerful, and so expensive, it could only be built if they all cooperated.

At Snowmass, American physicists from the high-energy Fermilab worried aloud that lack of U.S. funding might kill the project. Michael Holland, from the White House Office of Management and Budget, advised scientists that to get funding, they needed to demonstrate the device would be important to science in general.

This is precisely the point. Because elementary particle physicists have never been able to explain what practical applications—if any—might come from their work, high-energy labs are too expensive to be funded with taxpayer dollars. Simply put, particle physics scientists are still unable to withstand the relevancy and applications test when confronted with questions about why their projects should be publicly funded.

Physicists on the Offensive

Their best argument for doing the research is the one stated earlier: if we do not fund the expensive projects, the United States will no longer be in a leadership role in particle physics. Their second argument is that if we do not have funding, workers and physicists will lose their jobs. Neither argument is strong enough to warrant such high-cost public funding.

Physicists seem to realize this, and they are already on the offensive. At a meeting at Johns Hopkins University in March 2001, prior to the June particle physics meeting at Snowmass, physicists expressed concern that their research would not get funding and, as a result, go the way of SSC.

"That decision (SSC) was a real blow to the high-energy physics community, and ended up forcing many of us to go for extended periods of time to collider facilities in Europe," said Morris Swartz, professor of physics at Johns Hopkins.

The U.S. Congress and taxpayers are not stingy when it comes to funding science; however, they prefer funding medical research and for good reasons. Medical research has been shown to have an impact on everyday life. Finding Higgs boson will likely not. It is unlikely that any knowledge from high-energy physics will have a clear impact on the wealth and health of Americans.

Although expensive research, it was prudent in the 1990s to fund work such as the Human Genome Project. With the human genetic system now mapped, scientists are daily gaining insight into which genes may be responsible for diseases and disability. No such practical and beneficial outcomes can result from expensive experiments in particle physics.

Letting Go of a Cold War Mentality

Americans should not be concerned that the nation is not at the forefront of elementary particle physics. Once the knowledge is gained—whether in Europe, Asia, or North America—it can be applied anywhere. People in other countries will not have a monopoly on the information gained through this research. Just as people the world over, not just Americans, have benefited from American medical research (and even from American outer space research) so will Americans benefit from physics research, if there is truly a benefit to be had.

That the United States should lead the world in science, no matter what science, no matter what the cost, is a Cold War mentality that seeks to one-up the rest of the world. Being one up is expensive and unnecessary in the twenty-first century. Even particle physicists seem to have realized this as they talked about international cooperation at Snowmass.

In a letter to Physics Today during the SSC debate, Mark Phillips, a researcher in radiation physics at the University of Washington Medical Center in Seattle, said the aims of not only SSC but big funding for particle physics research is suspect. "Not every scientist, nor every citizen, for that matter, believes that spending tens of billions of dollars on this project [SSC and high-energy physics] is the sine qua non of American scientific commitment. In essence, every man, woman and child in the US is being asked to donate $30 (for construction alone) of the SSC… . I hope that every physicist is equally generous with his or her own money when environmental, religious or lobbying organizations come to the door asking for donations." His argument is still a good one today.

Also writing in Physics Today at the time of the SSC debate was scientist and entrepreneur Lon Hocker. His arguments against SSC then are also relevant to the argument against spending money on particle physics today.

"The SSC [was] a huge opportunity for pork barrel spending," wrote Hocker, "as well as an uninspired extension of a remarkably useless science… . High-energy physics shows no con ceivable benefit to anyone other than a few politicians, contractors and scientists… . The $10 billion planned for SSC could be spent on $10,000 educational grants to a million physics students, or ten thousand $1,000,000 research grants."

Other funding questions then and now for so-called big science ask by which criteria do we decide that one kind of science is more important to fund than another. Small science and not terribly expensive science can also be productive.

Conclusion

Currently, physicists are lobbying the Bush administration for increased funding for the Department of Energy (DoE), the agency under which high-energy labs would receive funding and do their work. The Bush budget for 2003 gives the DoE $19 billion, $700 million less than it had in 2001. By contrast, the National Institutes of Health will get $23 billion in 2003 and the Defense Department $310.5 billion. The portion of the DoE funds that would go toward particle physics is rather small by comparison. These figures mean the government thinks the tangible benefits from elementary particle research are not worth increased funding.

The cost of high-energy labs is too great for public funding, and scientists should seek out private funding. The DoE also has small science projects in materials engineering, computing, and chemistry, all of which could have greater relevance to life on Earth. More emphasis should be given to alternatives to big science research money.

—RANDOLPH FILLMORE

KEY TERMS

PARTICLE ACCELERATOR:

Device designed to accelerate charged particles to high energies. Often used in scientific research to produce collisions of particles to observe the subatomic debris that results.

PARTICLE PHYSICS:

Branch of physics concerned with subatomic particles, especially with the many unstable particles found by the use of particle accelerators and with the study of high-energy collisions.