The National Academies of Sciences, Engineering, and Medicine are conducting a study to assess key science questions that will drive research in the field of elementary particle physics for the next decade and beyond. The study, called Elementary Particle Physics: Progress and Promise (EPP-2024), will examine existing and envisioned approaches and tools used by particle physicists, as well as nascent technological developments and potential crossovers from other areas of science.

Co-chairs of the study committee, Maria Spiropulu, Shang-Yi Ch’en Professor of Physics at the California Institute of Technology, and Michael S. Turner, senior strategic advisor at the Kavli Foundation and Rauner Distinguished Service Professor Emeritus at the University of Chicago, answered some questions about the study; the report is expected to come out in spring 2024.

Q: What is elementary particle physics? What is the field’s significance?

Turner: The mission of elementary particle physics is to understand the fundamental nature of matter, energy, space, and time. We can trace its origins back two thousand years to the ancient Greek philosophers who proposed the idea of atoms, the indivisible constituents of all matter. Since then, we’ve discovered the atoms of chemistry — and other “subatomic” particles including electrons, protons, quarks, and neutrinos. It is clear the journey is far from over.

Understanding matter, energy, space, and time at the most fundamental level has been central to reaping the benefits that come from science, from chemistry to quantum mechanics. Further, this quest to understand at the most basic level has led to the development of tools — from accelerators and imaging devices to the World Wide Web — that greatly benefit us all. If history is any guide, an even deeper understanding of matter, energy, space, and time will lead to even more benefits for humankind.

Q: What are the purposes and goals of your study?

Spiropulu: We aim to articulate a long-term grand vision for elementary particle physics, along with the approaches and tools needed to realize it and to overcome the challenges we are likely to face along the way. EPP depends on discoveries and developments made in almost all subfields of physics and engineering, and as the field has been growing, so too has the degree of ingenuity required to provide viable methods for experimental exploration. The resulting technological developments have implication far broader than their use in particle physics.

Therefore, our committee will investigate if and how discoveries and insights from other areas of science can be applied to addressing the fundamental questions that drive the research in EPP, including exploring and envisioning intersections and exchanges with seemingly unrelated areas in technology and engineering. Indeed, the study of the most fundamental constituents of matter and energy may be entities beyond elementary particles as we have formulated them so far, so we want to explore this, too.

Q: How is your study related to the 2006 National Academies report Revealing the Hidden Nature of Space and Time?

Turner: The 2006 report assessed scientific challenges in particle physics, including key questions and experimental opportunities, and set priorities for moving forward. The committee that authored it, about half of whose members were from outside the field, strongly affirmed the importance of U.S. involvement and leadership in EPP, because of the scientific opportunities it offers as well as the fact that it is an attractor of domestic and international talent for students at all levels.

There have been significant advances and changes in particle physics in the past 16 years. Experiments at the Large Hadron Collider in Geneva — which the U.S. has participated in — have led to many discoveries, including the Higgs boson in 2012. The scientific questions have become bigger and the breadth of activities to address them has expanded. The origin of space and time, and the nature of dark matter and dark energy are now front and center. The scientists involved in particle physics now include astrophysicists, cosmologists, nuclear and atomic physicists, and computer scientists. Rather than setting priorities, our study will be framing a long-term vision informed by the advances of the past two decades and identifying the approaches to achieve that vision.

Q: How are you involving the particle physics community in the work of your study?

Spiropulu: We see this committee’s work as being a part of the community’s future-looking efforts. The committee members bring diverse backgrounds from labs and universities across the country, with a wide range of expertise. Working to involve other scholars, researchers, and stakeholders during the study process is important for the success of EPP-2024, and the committee is relying on harnessing some of the great energy and excitement in the community during the study process.

The committee held its first meeting recently in Seattle, during the Snowmass Summer Community Study organized by the American Physical Society’s Division of Particles and Fields. That community study is a massive effort that provides community-based input to the Department of Energy and National Science Foundation’s Particle Physics Project Prioritization Panel (P5) process. EPP-2024 builds off the Snowmass process, so it was extremely useful to have Snowmass participants and organizers contribute to our first meeting, as was hearing from the agencies and lab representatives. Further meetings will provide opportunities for the committee to hear from other stakeholders and continue to engage the larger community.

Additionally, the committee has put out a call to the community for Vision Papers that concisely and compellingly articulate scientific aspirations of the field for the next 10 to 30 years. Together, the Vision Papers, Snowmass white papers and reports, and P5 results will provide a critical set of inputs for EPP-2024. The EPP-2024 committee will use this input and fact-finding meetings over the next year to build a grand vision for particle physics that communicates the long-term opportunities of the field in a compelling way.

Q: How do you imagine your findings and recommendations could be used, and by whom, once they are released?

Turner: We hope that by articulating the aspirations and vision for the field, and approaches that can achieve those grand opportunities, our report will inspire students to careers in particle physics, motivate new scientific collaborations across disciplinary boundaries, and inform policymakers and academic leadership about the prospects for, and societal benefits of, particle physics research.

Learn more about this study, and save the date for a town hall on Oct. 13, which will focus on the experiences of early-career scientists.