The Strategic Framework
This chapter presents the committee’s strategic framework for the U.S. particle physics program. This framework is based both on the unusually exciting scientific challenges now facing particle physics and on the committee’s belief that a strong role in this area is necessary if the nation is to sustain its leadership in science and technology over the long term. The committee’s chief findings and recommended action items, which appear in the next chapter, are based on the strategic framework and budget scenarios presented in this chapter.
THE SCIENTIFIC CHALLENGE
Elementary particle physics advances by posing deep questions about the origin and character of some of nature’s most fundamental entities and conducting experiments to answer those questions. The experiments not only yield new knowledge of nature’s laws and develop new technologies, they also almost inevitably lead to even more profound questions. On this voyage of discovery, major scientific breakthroughs are achieved when important questions begin to intersect in unexpected ways, producing a deeper and more fundamental understanding of the phenomena being studied. Elementary particle physics is at such a moment now, when great questions are before it and the field is poised to answer them.
A century of revolutionary discoveries, together with the development of new technologies, has produced a dazzling array of scientific challenges in particle physics. The scientific challenges and opportunities for discovery on both the
scientific and technological frontiers, particularly for exploration at Terascale energies, are extraordinarily exciting. The opportunities now accessible to particle physics include moving beyond the limitations of the Standard Model, exploring further the unification of forces, probing the origin of mass, uncovering the dynamic nature of the vacuum, deepening the understanding of stellar and nuclear processes, and investigating the nature of dark energy and dark matter. These possibilities suggest that a great deal of new physics may be discovered in the next generation of experiments.
THE POSITION OF THE U.S. PROGRAM
Despite an extraordinary tradition of U.S. leadership in this area of science, the intellectual center of gravity in most areas of particle physics will move abroad with the termination in the next few years of the B-factory experiment at SLAC, the CLEO experiment at Cornell, and the CDF and D0 experiments at Fermilab. Moreover, this will occur just at the moment when especially exciting and important scientific opportunities have appeared on the horizon.
The U.S. program in elementary particle physics is therefore at a crossroads. On the one hand, there is an opportunity to reallocate substantial resources to begin exploiting new opportunities as existing experimental programs are completed over the next 2 to 4 years. Further, the United States has the necessary human capital, technology, and industrial expertise to be a leader in the pursuit of the scientific challenges of elementary particle physics. Indeed, it has a large pool of particle physicists, accelerator scientists, advanced students, and other talented researchers who can identify and pursue the most important and challenging questions in the field.
On the other hand, if the United States is to exploit these opportunities—and in the process fire the imagination and creativity of the next generation of students and scientists—decisive actions must be taken now. These actions will require a new strategic framework that establishes priorities designed to ensure a leadership role for the United States in the decades ahead and points to the difficult decisions required to act on those priorities. Moreover, regaining the long-term momentum of the program in elementary particle physics and reestablishing a position of leadership require a willingness to take scientific and technological risks and to consider important institutional transformations. While this effort will be a demanding one, the failure to take up the challenges might lead some of the best U.S. scientists and students to disperse abroad or to other fields of endeavor, undermining the nation’s opportunity to continue to play a leadership role in this fundamental scientific area.
Fortunately, because several of the nation’s most important experiments in particle physics are coming to an end, reallocation of resources within the program would allow the U.S. particle physics research community to begin to implement a strategic vision that is consistent with contemporary scientific developments and with sustained U.S. leadership in the field.
The committee feels strongly that because of the increasing cost and complexity of particle physics experiments, and the need to deploy public funds in the most effective and responsible manner, it is more important than ever for all the large programs in particle physics to leverage their resources by working together internationally. The community of particle physicists has a strong tradition in this area, but that tradition needs to be enhanced. There is an increasing need for particle physics programs in the United States and elsewhere to take fuller advantage of important experiments proceeding in other countries. Moreover, the key sponsors of national and multinational programs need to allow for the serious consideration of new and imaginative arrangements. Such arrangements would not only serve the cause of scientific progress, they might also be the only way to provide scientists and their students around the world the opportunity to address those areas of particle physics to which they can make the greatest scientific contribution. This type of transformation cannot be accomplished by a single country or region. It requires the mutual collaboration of all major partners. From the perspective of the U.S. program in particle physics, such arrangements could be of great value as they would give U.S.-based researchers better access both to a wider portion of the scientific frontier and to a wider range of opportunities. Such changes would strengthen the knowledge base of the entire U.S. scientific enterprise.
In crafting a strategic plan for the U.S. program in particle physics over the next 15 years, it is important to identify and balance the risks that are inherent in any such activity. First, there are scientific risks. Frontier experiments push the boundaries of human experience; it is never certain what lies beyond current knowledge. Because of that, the particular shape, focus, and character of the next set of experiments can be expected to evolve, at least in part, in unexpected and unpredictable ways. Second, there are unavoidable structural risks. Experimental facilities for elementary particle physics are constructed and supported by government funds, so planning must factor in uncertainties surrounding future government investments in science, in general, and in elementary particle physics, in particular. Third, there are special risks associated with the most important of the next generation of experiments, the proposed ILC. The ILC is a very large project, and important and critical investments must be made before it is certain that an international consortium can be assembled to construct and operate the collider
and before a decision can be made about where it will be sited. A willingness to accept these risks is an inevitable aspect of a leadership position at the scientific and technological frontiers.
The committee emphasizes that while investment in specific scientific projects always carries risk, leadership in science is central to the nation’s strategic and economic security. Science is concerned with the investigation of the unknown, so one cannot be certain in advance of the dividends that will be achieved, either in new scientific understanding or in novel technological developments. Any large scientific project carries additional risks because new experiments push technology to new frontiers. In this respect, however, elementary particle physicists have accumulated an enviable record in meeting technological challenges. In the process, they have provided society with an array of useful innovations in science, medicine, and industry (such as in computing and in medical imaging and treatment). It should also be kept in mind that there are greater risks in not exploiting scientific opportunities and in forgoing the potential benefits to society and human development. The risks of inaction are difficult to assess fully, but they may be quite significant.1
In crafting its recommendations, the committee first articulated a set of strategic principles designed to provide an overall framework for the U.S. program in particle physics. These principles are presented in the remainder of this chapter. Within the context of these strategic principles, the committee, on the basis of its specific findings, worked out a set of recommended action items reflecting the priorities that it believes ought to guide the program over the next 15 years. The findings and recommended action items are presented in Chapter 5.
THE STRATEGIC PRINCIPLES
In the modern era, leadership in particle physics does not mean dominance. Rather, it means playing a central role in new scientific discoveries, which can be done by taking initiatives on the scientific frontier, accepting risks, and catalyzing partnerships with colleagues at home and abroad. In the contemporary world of particle physics, none of the national and/or regional programs is—or can be expected to be—in an overall leadership position in the sense of command and
control or singular dominance. There are, however, a small number of national and regional programs that are currently exerting leadership in the sense of providing a continuing stream of significant intellectual and experimental contributions to the most important issues on the scientific frontier. As a result, these programs have a major influence on the evolving profile of the field and are in the best position to exploit the scientific and technological developments that emerge and to initiate and mobilize joint international efforts. Thus, the committee’s practical definition of leadership (provided above) is a statement of aspiration in all these areas (intellectual relevance, active participation on the frontiers of science and technology, acceptance of risk, and catalysis of international partnerships), and it is the kind of leadership that the United States should seek to maintain in the years ahead. Therefore, in considering the U.S. program in particle physics for the next 15 years, the committee sought not only to pursue the most compelling scientific opportunities but also to reestablish a clear path to a position of leadership in particle physics.
Strategic Principle 1: The National Importance of Elementary Particle Physics. The committee affirms the intrinsic value of elementary particle physics as part of the broader scientific and technological enterprise and identifies it as a key priority within the physical sciences.
The current scientific and technological prowess of the United States is due in no small part to the nation’s investments in basic research in the physical sciences. Elementary particle physics is an important part of this research portfolio, through both its contributions to a variety of scientific fields and its being an integral part of the broader inquiry into the basic workings of nature.
One example of the interplay between particle physics and other fields of physics is the development and application of a set of mathematical tools known as quantum field theory. Quantum field theory generalizes the principles of quantum mechanics to situations where the number of particles is not constant, and it provides an exhaustive framework for calculating complex phenomena. Quantum field theory has now become a general tool for a wide variety of theoretical physicists. For instance, condensed matter physicists use quantum field theories to describe phenomena such as superconductivity and phase transitions. In fact, certain advances in particle physics theory can be traced to inspirations from condensed matter uses of quantum field theory. Other examples of the intellectual connection between particle physics and the broader enterprise of physics involve the joint development and deployment of scientific instrumentation. For instance, it was the advent of large-scale semiconductor manufacturing in the 1980s that led to the development of a new generation of particle detectors using large surfaces of purified silicon; later, the technologies perfected by particle physicists found appli-
cation in space-based observing platforms such as the GLAST satellite. Vice versa, particle physicists’ interest in novel radiation-hard particle detection technologies led to the development of thin-film diamond sensors, which now have emerging applications in medical diagnostics and monitoring.
Perhaps the most important contributions of particle physics to the broader economy in recent years came from the development of the key protocols that underpin the World Wide Web at the CERN laboratory. SLAC was the first U.S. entity connected to the Web; Fermilab was the second. Building on the backbone of the already existing Internet, this new way of sharing information has revolutionized the way the world communicates and does business. The synergy between particle physics and cyberinfrastructure has played a strong role in the history of both fields. As new computing, information sharing, and data handling capabilities have become available, particle physics has embraced them and has been instrumental in developing many of the advances. Even today, physicists are working with their colleagues in computer and information science to implement architectures for shared computing access to the LHC experiment.
These advances arose because of a synergy between particle physics and other developments in science and technology; that is, the committee does not claim that particle physics is the best or only driver of such innovations. Rather, it argues that a strong program in particle physics is an essential element of an overall strategy to foster such breakthroughs.
Most important, as described in Chapter 3, the committee identifies elementary particle physics as a research effort that is poised to make transformative discoveries in the immediate future. The frontiers of human understanding are always advancing, yet the committee was struck by the tremendous discovery potential of particle physics over the next decade. Furthermore, the emerging connections among particle physics, astrophysics, cosmology, and nuclear physics are extremely promising signs of breakthrough opportunities.
There is every expectation that discoveries at the Terascale will ripple across the fields of science as new insight is gained into the nature of space and time, energy and matter.
Strategic Principle 2: U.S. Leadership. The U.S. program in elementary particle physics should be characterized by a commitment to leadership within the global particle physics enterprise.
The argument for a leadership role is multidimensional. First, the committee believes that leadership in this important and challenging area of science is critical to the overall strength of U.S. science and its role as an engine of economic growth through innovation. The connection between economic leadership and the physical sciences and mathematics has been strongly articulated in the recent National
Academies report Rising Above the Gathering Storm.2 Particle physics is critical in this respect. It has a strong position at the forefront of technology, and its quest to understand elementary particles and fundamental phenomena connects it to many other areas of science as well as to industry. This is particularly true for accelerator R&D, which has created the accelerators that generate radiation for medical therapies and the x-ray beams that are now pushing the edge of bioscience and materials science. It has also been true of the other parts of particle physics in a variety of ways.
Second, unless the United States undertakes the challenge of leadership, scientists here will be unable to work effectively with their colleagues abroad. As asserted in Allocating Federal Funds for Science and Technology, “Science is a global enterprise in which the United States must participate, for its own benefit and for that of the world.”3 However, owing to the increasing capabilities of particle physics research programs in other countries, as well as the increasing cost of experiments, it is neither desirable nor feasible for the United States, or any other country, to host experimental facilities in every area of elementary particle physics. Instead, the United States must become a leader in particle physics through a combination of efforts: investing strategically in projects located in other countries, hosting particle physics projects with some of the greater potential for discovery, and ensuring that U.S. programs make the best use of particle physics personnel, facilities, and resources. That is, to remain competitive, the United States must seek collaborations that confer mutual advantage.
Third, occupying a leadership position will ensure that the United States reaps the dividends of new discoveries and ensures vitality for its next generation of scientists. As described in Globalization of Materials Research and Development: Time for a National Strategy,4 ensuring U.S. access to cutting-edge science and technology, no matter where the next breakthroughs may occur, is a key reason for staying active at the frontiers of research. Permanently abandoning leadership in particle physics will have profound consequences. Not only will U.S. scientists, students, and engineers fall behind their colleagues in the rest of the world, but our nation will have given up on one of the key drivers of scientific and technological innovation.
With respect to future international joint efforts that might be based outside
the United States, the committee identified some neutrino physics experiments, a proton decay experiment, and/or a super-B factory as important examples. As already noted, the proposed ILC will certainly require an international joint effort; it also will require a major commitment of U.S. particle physics resources to succeed wherever it is based. The United States is already an active participant at the LHC at CERN as well as at other laboratories abroad, such as DESY in Germany, KEK in Japan, and the Sudbury Neutrino Observatory (SNO) laboratory in Canada. The U.S. particle physics program should continue to seek international partners to share the costs of U.S.-based efforts, just as the United States invests in overseas efforts.
Strategic Principle 3: A Global Particle Physics Program. As the global particle physics research program becomes increasingly integrated, the U.S. program in particle physics should be planned and executed with greater emphasis on strategic international partnerships. The United States should lead in mobilizing the interests of international partners to jointly plan, site, and sponsor the most effective and most important experimental facilities.
The next generation of experiments will require more complex and expensive experimental facilities, including underground laboratory spaces for neutrino physics, dark matter searches, and proton decay experiments; possible upgrades of the LHC accelerator and detectors; intense neutrino beams and associated detectors for a second generation of long-baseline neutrino oscillation experiments; ground- and space-based efforts for particle astrophysics experiments; a possible future super-B factory; and, most ambitious of all, the ILC. One testament to the success of the pooling of international (predominantly European) resources and talents is the CERN laboratory in Geneva.
To achieve and maintain a leadership position in the global particle physics program and to maximize the return on the public resources invested, the United States must take the initiative in establishing joint programs aimed at exploiting the scientific potential of the largest, most complex, and most expensive of the next generation of experimental facilities. This implies that the United States should be willing to provide and be the lead investor in the appropriate facilities for some major part of the science at the forefront of the field and to welcome scientists from abroad as partners. It also implies that the United States should be willing to invest in important scientific opportunities or key experimental facilities located abroad. A critical (and often overlooked) aspect of participation in such a global program is the need for international discussion and coordination from start to finish of a project; that is, nations should consider and consult potential partners for a candidate project before, during, and long after the design, develop-
ment, and engineering stages of a project begin. Just as in business relationships, valued and productive partnerships spring from early joint ownership of the project.
The strategic objective is to work with the nation’s scientific partners abroad and their sponsors to forge an international partnership that deploys public investments in the most efficient and effective manner.5 The committee believes that the globalization of scientific research, especially in particle physics, has opened a new path to leadership. For the United States to be globally competitive, attain national goals, and realize the most compelling scientific opportunities, the nation must plan and pursue the most critical ventures with international partners.
Strategic Principle 4: The Necessary Characteristics of a Leadership Program. The committee believes that the U.S. program in elementary particle physics must be characterized by the following to achieve and sustain a leadership position. Together, these characteristics provide for a program in particle physics that will be lasting and continuously beneficial:
A long-term vision,
A clear set of priorities,
A willingness to take scientific risks where justified by the potential for major advances,
A determination to seek mutually advantageous joint ventures with colleagues abroad,
A considerable degree of flexibility and resiliency,
A budget consistent with an aspiration for leadership, and
As robust and diversified a portfolio of research efforts as investment levels permit.
The last of these characteristics deserves special emphasis. A broad array of scientific opportunities exists in elementary particle physics, and it is not possible
to foretell which of them will yield important new results soonest. Particle physics, like all other elements of the scientific enterprise, explores the unknown, and this inevitably requires shouldering some uncertainty. Thus, it is important to maintain a diverse and comprehensive portfolio of research activities—from theory to accelerator R&D to the construction of new experimental facilities to efforts to probe entirely new areas. Two of the greatest discoveries of the last decade—the discovery of nonzero neutrino masses and of dark energy—were completely unexpected, underscoring the need for a variety of approaches to current scientific challenges.
Even during a period of budgetary stringency, sufficient funding and diversity must be retained in the pipeline of projects so that the United States is positioned to participate in the most exciting science wherever it occurs. It is essential, therefore, to follow a mixed strategy that encompasses a variety of experimental approaches, arrangements that allow for the most advanced training of the next generation of scientists, investments in future detector and accelerator technologies, adequate computational resources, support for theoretical work, and the capacity to support small and innovative experiments. The relatively flat funding of the U.S. particle physics enterprise over the past decade has, unfortunately, forced a relative reduction in its diversity. Moreover, uncertainties over future support make some investigators more conservative in their research, leading them to work on more established, predictable topics.
For full participation in the international arena, the United States must coordinate, and in some cases subordinate, its planning to international planning and advisory structures such as IUPAP and ICFA. It is important to design mechanisms whereby joint programs incorporate the best ideas from all around the world. This means that duplicative preliminary work on projects must be supported for the best possible approaches to emerge. The effort to eliminate duplication of large projects should not end up suppressing the development of competing approaches too early in the process. At the same time, some international mechanism is needed to ensure that only the most promising approaches are supported.
The breadth of the U.S.-based program is an important factor. The U.S. particle physics program has benefited from a strong tradition of investments in the human, institutional, and physical infrastructure. For instance, the United States has been at the forefront of advancing the theoretical underpinnings of particle physics, which has had a profound effect on the shape of the experimental program. In turn, new theories have emerged from experimental results. The close relationship between
theory and experiment has been a key driver of U.S. leadership in this field, and it is important to nurture this relationship. Another example of this tradition is the historical stewardship of accelerator science and technology by the nation’s elementary particle physics program. Particle accelerators continue to affect a broad spectrum of scientific and technological activities. Advanced research into new accelerator technologies is vital to the future of accelerator-based elementary particle physics as well as to emerging technologies in other areas. The United States should strive to remain a lead player in this area.
The success and vitality of the scientific enterprise depend on a distinctive set of institutional arrangements for training new scientists. The committee views the current role of university-based students, postdoctoral researchers, and faculty as a critical component of the particle physics enterprise that strengthens national capabilities in both education and science. The strength of the university-based program also depends directly on a healthy, competitive peer-review system that identifies and supports the best science.6 The framework of competitive peer review ought to govern the allocation of resources to the greatest extent practicable. Fair competition among competing ideas, be it at the individual investigator level or at the level of laboratory program initiatives, helps select and support the most compelling, ripest for exploitation of the science.
THE BUDGETARY FRAMEWORK
Recent Trends in Support for the U.S. Particle Physics Program
The U.S. program in elementary particle physics has not experienced any real growth in a decade. The committee estimates that over the last 5 years (FY2001 through FY2006) funding for this area of science declined by 5 percent in real terms (see Box 1-4). Some of the key U.S.-based experimental facilities in elementary particle physics are either being converted to serve other uses (the SLAC linear accelerator and the CESR accelerator) or are coming to the end of their scientific lives (the CDF and D0 experiments at Fermilab’s Tevatron). This provides an opportunity to strategically reallocate these funds as part of a new and exciting long-term vision for the U.S. program, which, despite the circumstances, may be surprisingly well situated to consider new directions and new initiatives.
Legislative and executive branch response to the overarching issues identified in Rising Above the Gathering Storm7 could foretell a brighter future. The President’s American Competitiveness Initiative and the President’s requested budget for FY2007 represent a welcome change in the funding outlook for elementary particle physics. The suggested increases in funding would help to enable the long-term vision for the U.S. program advocated in this report.
Multiyear Plans and Budgets
Many important experiments in particle physics require long-term investments and therefore multiyear plans and budgets. While the implementation of the priorities recommended below needs to be sensitive to budget realities, and also be sufficiently flexible to adapt to changes in the budget outlook, it is critical for the vitality of the U.S. program in particle physics to operate within the context of a long-range strategic plan. Indeed, in the FY2005 Energy and Water Development Appropriations Act, Congress directed DOE to develop a 5-year plan for DOE’s Office of Science Programs, including the high-energy physics program. This plan enables program managers to develop more detailed and transparent multiyear plans.
The ability to make longer-term plans and commitments is also critical for international partnerships. One of the greatest challenges to U.S. leadership in future scientific activities, particularly in the case of particle physics, is to convince international colleagues that the U.S. political and budgeting processes are capable of sustaining the multiyear commitments that are negotiated when planning a joint venture. The sizeable U.S. investment in the LHC construction project at CERN (more than $500 million over 10 years) is an important demonstration that the U.S. particle physics program can make stable, long-term commitments.
Strategic Principle 5: Effective Long-Term Budget Planning. The Secretary of Energy and the Director of the National Science Foundation, working with the White House Office of Science and Technology Policy and the Office of Management and Budget and in consultation with the relevant authorization and appropriations committees of Congress, should, as a matter of strategic policy establish a 10- to 15-year budget plan for the elementary particle physics program.
In the shorter run, given particular budgetary contingencies, the committee recommends that any necessary adjustment to plans be carried out in consultation with the research community.
NATIONAL PROGRAM CONSIDERATIONS
Strategic Principle 6: The Role of Fermilab. A strong and vital Fermilab is an essential element of U.S. leadership in elementary particle physics. Fermilab must play a major role in advancing the priorities identified in this report.
Particle physics benefits from close collaboration between universities and laboratories coast to coast. Over the years, each major laboratory involved in particle physics supported its own community of researchers both at the laboratory itself and at universities, creating a powerful synergy between these two communities that strengthened the national program. Fermilab has been no exception; research conducted at its Tevatron by laboratory staff and university collaborators has helped pave the way to the Terascale.
In recent years, however, the number of laboratories primarily devoted to particle physics has been shrinking. For instance, Brookhaven National Laboratory began to focus on nuclear physics in 1999. DOE’s Basic Energy Sciences program became the major funder of SLAC in 2005. The current accelerator-based particle physics programs at Cornell, SLAC, and Fermilab are scheduled to be completed by 2009. After that, Fermilab will become the nation’s only laboratory devoted primarily to particle physics. Continuing efforts at other major laboratories and from university groups will, however, be essential to realize the full potential of the nation’s scientific agenda and regain the vitality and distinction of the U.S. program in particle physics. So, while a strong and vital Fermilab remains the essential element of U.S. leadership in this field, the overall program will also require a coordinated infrastructure of talent, resources, and leadership from other national laboratories and universities.
Whether or not it has an operating accelerator, Fermilab will be the focus of national efforts in Terascale physics, both by facilitating U.S. partnership in the LHC and spearheading U.S. participation in the ILC. It has the facilities, infrastructure, and intellectual capital needed to support U.S. particle physics, whether the experiments are conducted at home or abroad. There is no doubt that a distinguished national program requires a distinguished Fermilab. In addition, initial assessments of the area surrounding Fermilab indicate that it would satisfy some of the geological and environmental conditions required for the ILC, making Fermilab a natural choice for siting the ILC in the United States.
In any case, the committee expects that Fermilab will support and help mobi-
lize the national program of particle physics research in the years ahead. In this new context, it is essential that Fermilab’s internal priorities be aligned with those of the broader U.S. community.
Strategic Principle 7: The Advisory Structure in Particle Physics. A standing national program committee should be established to evaluate the merits of specific projects and to make recommendations to DOE and NSF about the national particle physics program in the context of international efforts.
The changing environment in particle physics requires a reexamination of the advisory structure for the field. In the past, individual national laboratories had their own program committees that provided advice to the laboratory directors on the feasibility of experiments and their prioritization within the laboratory’s program. Ultimately, DOE in consultation with each director would approve the program for the laboratory, and DOE would provide the laboratory and associated university groups with the funding for the experiments. Overall program coordination has been facilitated by the HEPAP, a federal advisory committee originally charted in 1967; since 2000, it has been jointly chartered by NSF and DOE. As accelerator projects have become significantly larger and as more nonaccelerator programs have been proposed, a need has been recognized for a more comprehensive structure to establish national priorities in a time of tight fiscal constraints.
In November 2002, HEPAP implemented one of the central recommendations of its Long Range Planning Subpanel, established in 2001, to create the Particle Physics Project Prioritization Panel (P5). P5 was an ad hoc subpanel with a 2-year lifespan that has since been renewed. The tasks with which P5 has been charged have been changing over time as its responsibility grows. In early 2006, P5, together with its subpanels on dark energy, neutrino science, and other topics, was charged by the DOE Director of High Energy Physics and the NSF Assistant Director for Mathematical and Physical Sciences to develop and deliver to HEPAP a roadmap for particle physics.8 While it is too early to tell whether this roadmap process will be successful, a higher level of analysis and overview of the U.S. portfolio is a step in the right direction.
The combination of unparalleled scientific opportunities and fiscal constraints will force the particle physics community to make some very hard choices. Under such circumstances, it would be enormously advantageous to have a national particle physics advisory apparatus that advises DOE and NSF on the scope of the U.S.
HEPAP and its subcommittees are described on the DOE Office of High Energy Physics Web site at <http://www.er.doe.gov/hep/hepap.shtm>.
program and establishes priorities within the context of the international particle physics program. Its charge should be to evaluate the merits of specific proposals and make recommendations with regard to the national program to minimize unproductive duplication of overseas activities and to foster international collaboration for the benefit of science whenever practical. Such a coherent national advisory role could be played by an existing element of the high-energy physics program’s advisory apparatus, such as a P5 committee that has been modified by transforming it into a standing committee with a broader mandate. The details of the specific advisory structure should be left to the agencies involved. Plans for rotating membership and participation from across the United States, as well as internationally, should be clear and public.
Within these strategic principles, different overall resource commitments can and must be accommodated. However, there is a point—a level of resources— below which a leadership is not tenable. Every effort should be made to avoid this situation, but if it nonetheless occurs, the strategic principles outlined above will need to be significantly amended. This is not, of course, an easy point to identify, but there is some initial evidence that the U.S. particle physics program is nearing it. Neither the nation’s leaders in particle physics nor their sponsors have articulated or agreed on a compelling strategic plan that would sustain a distinctive leadership position for the U.S. program. That is, while the scientific community has identified the ILC as the highest priority project for the future, it has not succeeded in incorporating this element into a strategically focused program.
More generally, the current level of federal support for elementary particle physics presents an opportunity for strategic investment at the same time as it serves as an overall constraint. All priorities are set and the scope and timing of specific projects are decided with a budget in mind. The committee’s principal recommendations assume that the current U.S. budget for elementary particle physics will at a minimum receive increases tied to the rate of inflation in the immediate future (Scenario A). This scenario would reflect a decision by policy makers to proceed with at least a constant level of effort,9 although it implies that a smaller and smaller proportion of the U.S. gross national product would be
devoted to this aspect of the scientific enterprise. The committee uses this particular scenario as the “control case” in recommending priorities for the next few years. However, even in this scenario it will be a significant challenge to sustain a position of leadership. Thus, the committee’s initial set of recommendations and priorities assumes that there is a possibility of future growth in funding to allow for a critical major new initiative (Scenarios C and D). The possibility could be realized within the President’s proposed FY2007 budget, which increases federal support for the physical sciences.
A scenario in which the existing budget remains flat without any adjustments for inflation was also considered (Scenario B). This scenario, which would reflect a decision by policy makers to continue to disinvest in this area of science, is incompatible with the desire to achieve a position of leadership for the U.S. program. It is the committee’s view that such a policy would undermine any possibility that the United States will achieve a position of leadership as the committee has defined it. The consequences of such a decision for particle physics will be severe, and the implications for the nation’s involvement at the frontiers of science and technology are equally sobering.
In Scenarios C and D, mentioned above, the current budget is increased annually in real terms (increases in addition to inflationary adjustments) by 2 to 3 percent (C) or by as much as 10 percent for the 7 years beginning in 2008 (D), as recommended in Rising Above the Gathering Storm. Both of these policies would reflect a national decision to increase the level of effort because the scientific opportunities in the physical sciences, especially in elementary particle physics, are currently so compelling. Chapter 3 detailed many of the discoveries that would be possible in Scenario C or Scenario D; many of these would not be possible in the constant-effort budget, Scenario A. The President’s FY2007 budget request proposes an increase in funding for particle physics, which if implemented could be a step toward realizing Scenarios C or D. Figure 4-1 shows the four scenarios through the end of 2015.
The committee came to the alarming conclusion that for the United States to play a significant role in realizing the compelling science opportunities in elementary particle physics, the current short-term decline in inflation-adjusted resources devoted to this key area of science must be reversed as soon as possible. In the near term, funding levels should provide, at a minimum, a constant level of effort with perhaps some modest growth (Scenario A). Over the long term, a robust program will require leadership and real growth, somewhere between that posited for Scenarios C and D.
The committee is fully aware that real growth in the particle physics budget may take some time to be realized. It is essential, therefore, to reallocate those resources released from experiments scheduled to end in the next 3-4 years to fund
new elementary particle physics initiatives that address the most exciting scientific challenges. In a budget scenario that returns to real growth, it will be possible to achieve a position of distinctive leadership within a worldwide program and to support a diverse set of experiments that address current scientific questions more fully than is possible in the constant-effort scenario. As funding becomes available, either through new resources or from the conclusion of an existing activity, it should be allocated in accordance with the priorities outlined in this report.
In the long run, true leadership in particle physics will require augmentation of the resources devoted to the discipline. Simply put, the committee believes that the level of resources currently being committed to particle physics will be inadequate, in the long term, to obtain the technological, economic, social, and scientific benefits of undertaking the most compelling opportunities in this transformative area of science. Strengthening the U.S. role in particle physics will strengthen national and international confidence in the future of U.S. science and technology and in the image of the United States as a great nation supported by great science.
Finally, it is the committee’s view that the competitiveness of the global and domestic economic environment the nation faces necessitates an aggressive investment in the mathematical and physical sciences, including particle physics, as well as in other areas of fundamental research.