# Presentation: 432253

## Revealing the Hidden Nature of Space and Time

- Revealing the Hidden Nature of Space and Time

- Final Report of the Committee on Elementary Particle Physics in (the First Decades of) the 21st Century
- May  2006

**Sally Dawson and Chuck Shank**
*on behalf of the full committee*

## The “EPP2010” Committee

- National Academies convened this committee in response to an informal request from NSF and DOE to
- Identify the compelling questions that define the current particle physics agenda
- Recommend a 15-year implementation plan with realistic, **ordered priorities** to address them
- Half of the members were drawn from **outside** of particle physics
- Committee met six times in person and conducted numerous site visits & discussions around the world (KEK, J-PARC, DESY, CERN, SLAC, Fermilab, Cornell)

| Harold T. Shapiro, Chair
Princeton University | Sally Dawson, Vice Chair
Brookhaven Natl. Lab |
| --- | --- |
| Norman Augustine
Lockheed Martin (retired) | Neal Lane
Rice University |
| Jonathan Bagger
Johns Hopkins University | Nigel Lockyer
University of Penn |
| Philip Burrows
Oxford University | Sidney Nagel
University of Chicago |
| Sandra Faber
University of California Observatories | Homer Neal
University of Michigan |
| Stuart Freedman
University of California, Berkeley | Ritchie Patterson
Cornell University |
| Jerome Friedman
MIT | Helen Quinn
Stanford Linear Accel. Center |
| David Gross
Kavli Inst for Theor. Physics | Charles Shank
Lawrence Berkeley Natl. Lab |
| Joseph Hezir
EOP Group, Inc. | Paul Steinhardt
Princeton University |
| Norbert Holtkamp
Oak Ridge Natl. Lab | Harold Varmus
Sloan-Kettering |
| Takaaki Kajita
University of Tokyo | Edward Witten
Inst. for Advanced Study |

## Context of the Report

- The report examines and is framed by:
- The nature of the scientific opportunities
- The current status of the U.S. program
- An articulation of a set of strategic principles
- Evaluation of alternative sets of priorities
- Reasonable budget assumptions
- (The ongoing national discussion of competitiveness, innovation, and the future position of U.S. science and technology)

## Unusual Features of this Report

- Over the past 10 years, many committees have examined the future of elementary particle physics
- What makes this assessment by the National Academies  different?
- Committee membership was unusual in its breadth and its depth
- Over half of the committee members were drawn from outside particle physics, bringing expertise in astronomy, astrophysics, condensed-matter physics, AMO science, even genetics, aerospace engineering, and economics
- Report reflects the efforts of a broad group of experienced individuals to place the particle physics agenda in a larger context in order to understand the significance of the current opportunities

## We worked hard

- Committee met at SLAC, Fermilab, Cornell, Washington
- Input from community invaluable
- Town meetings
- Written answers to committee questions
- Discovering the Quantum Universe (Lykken/Siegrist)
***CANNOT STUDY EPP EXCEPT IN A GLOBAL CONTEXT***
- We went to KEK, JPARC, DESY, CERN
- Met with INFN director, Brian Foster, ACFA chair, ICFA chair
- Non-particle physicists actively engaged

## Nature of the Scientific Opportunities(Does Particle Physics Still Matter?)

- As a committee of skeptics, outsiders, and insiders, how _*exciting*_ were the scientific opportunities in particle physics?
- The committee concluded that particle physics continues to be a critical component of the physical sciences
- Intellectual vitality and connectedness to many other fields
- Inspiration to and attractor for young people
- One of the drivers of technological frontiers
- The committee also concluded that the scientific agenda is especially _***exciting***_ at the present time
- Indeed, we are perhaps entering the most exciting era of particle physics in at least a generation
- In addition, we are at a pivotal moment
- Answers to long-standing questions are within reach
- Convergence of separate lines of inquiries has special significance
- New tools such as the LHC and _***proposed***_ ILC are poised to address these mysteries and make profound discoveries

## Status of the U.S. Program

- Historical distinction
- Stagnating level of support for past 10 years
- Intellectual center of gravity moving abroad
- Major experiments are coming to the end of their scientifically useful lives
- There is no clear follow-on plan in place
- Significant risk of losing substantial (intellectual and financial) resources
- However, there is a “silver lining”
- As facilities close or change focus, resources are becoming available to support and launch new initiatives

## Is There a Leadership Strategy Going Forward?

- In the context of the global effort, to what role should the United States aspire?
- Without achieving a leadership role within the global effort, the U.S. program could not sustain its distinction and would become a much smaller and less relevant effort
- Being among the leaders is critical for fully realizing the intellectual, economic, social, and cultural dividends
- Given the extraordinary scientific opportunities, the available human capital, and the current state of the U.S. effort, was there a path forward that could sustain (or regain) the United States distinction in this field?
- The committee articulated a strategic framework and evaluated several alternative strategies under different budget scenarios
- Clear priorities were proposed within this framework

## Strategic Framework (1)

- Particle physics is an important part of the national effort in the physical sciences
- Key intellectual role in physics
- Driver of scientific and technological frontiers
- Inspiration and attraction for future generations
- The United States should aspire to a leadership role in the global program of particle physics
- In the modern world, leadership does not mean singular dominance but rather taking initiative at the frontiers, accepting appropriate risks, and catalyzing partnerships both at home and abroad
_*We need to put greater emphasis on strategic international partnerships*_

## Strategic Framework (2)

- A diverse portfolio of activities is crucial
- Need for vision, priorities, _***risk taking, ***_flexibility, and responsible budgets
- To fully achieve the potential of particle physics, multi-year planning is required
- Large-scale science requires long-term commitment
- The administration of U.S. program in particle physics is poised for change
- With some national labs changing their focus, Fermilab will become even more central to the particle physics community
- A new level of national and international planning is required to provide a full range of opportunities to physicists, to explore a wide range of approaches, to be good stewards of public funds and thus to increase the probability of important discoveries
- Advisory and guidance processes for the field should be adjusted accordingly

## Alternative Sets of Priorities

- Committee considered a broad array of strategies and scenarios
- One set class of priorities rejected a major commitment to new accelerator facilities here, while another set of priorities included investments aimed at the establishment of new domestically based experimental facilities to study Terascale physics under laboratory conditions _***[i.e. the ILC]***_
- The committee believed that only a strategy which included a major commitment to exploit the Terascale opportunities both at the LHC _***and***_ with domestically based accelerator facilities would yield the highest risk adjusted return for the U.S. program and the best opportunity sustain (or regain) U.S. distinction in this area
- Choosing not to pursue the direct exploration of the Terascale would be equivalent to folding our hands and walking away from leadership in particle physics

## Ordered Priorities

- Exploit the opportunities offered by the LHC
- Plan and initiate a comprehensive program to participate in the global effort to complete the necessary R&D to design and plan an international linear collider
- Do what is necessary to mount an internationally compelling bid to build the international linear collider on U.S. soil
- Seize the opportunities at the intersection of particle physics, astrophysics, and cosmology by coordinating and expanding domestic efforts
- Pursue an internationally coordinated, staged program in the physics of neutrinos and proton decay
- Pursue precision probes of physics beyond the Standard Model using available resources as a guide to overall level of effort while maintaining diversity

## International Linear Collider

- Scientific role
- LHC will map out the territory, but a precision tool will be necessary for a comprehensive understanding
- Cost and schedule
- Global scientific consensus has led to a world-wide planning activity (the Global Design Effort)
- Key objective is determination of a credible design, cost, and schedule. However the committee proceeded under the assumption that the cost was ‘like’ the LHC and would require an international partnership.
- Relative timing
- ILC would only become tenable after cost and initial LHC results complete the grounds for decision-making.
- Opportunity for the United States
- Preliminary investment of _***risk capital***_ is needed
- A successful U.S. bid-to-host requires taking initiative now.

## Report in a Global Context

- The committee considered the U.S. role in the global effort at great length
- The nation must “pull its own weight” in terms of hosting next-generation facilities and catalyzing the international partnerships required to make them possible
- “The United States should move away from an almost certainly futile attempt to maintain dominance and toward an approach where leadership comes from developing and brokering mutual gains for partners”
- PAST: “We’re going to build this; will you help us?”
- FUTURE: “What can we best build together?”
- In articulating its priorities, the committee chose a strategy that leverages U.S. strengths for the global community and adds to the long-term vitality of the entire field

## What the Report Means for the National Laboratories

- Science program of the national laboratories is evolving
- Fermilab will become the only laboratory primarily devoted to particle physics
**Can a competitive, globally relevant national program be sustained without a major new accelerator facility (ILC) to access Terascale physics?**
- The committee thought very hard about this possibility but could not see a long-term leadership role for the U.S. in this scenario
- Fermilab will play a key role in mobilizing and working with the country’s best talent and resources in implementing a national vision that has strategic importance in the global context
- All of the national laboratories have unique roles to fill in this strategic vision
- Fermilab is a strong contender to have the ILC sited nearby
- Final decision will be political
- The committee recommends that the U.S. lead an international effort to consider how best to coordinate a long-term global effort with long-baseline neutrino experiments

## Take-Home Message

- Particle physics is at a crossroads
- Scientific discoveries are just within reach whose impact is likely to transform and even transcend particle physics
- U.S. facilities are being closed or converted to other uses and federal investments have stagnated
- Intellectual center of gravity is moving overseas with the construction of new facilities in Europe and Japan
- Without clear, decisive action in the next few years, the U.S. program will deteriorate
- The United States should continue to support a competitive program in this key scientific field
- The committee outlined a strategy that has the best chance to put the United States at the forefront of the field with a program of distinction and importance

## Q & A