# Presentation: 812343

## BESAC Subcommittee on Theory and Computation

***Co-Chairs***
- Bruce Harmon – Ames Lab
- Kate Kirby – ITAMP, Harvard Smithsonian Center for Astrophysics
- Bill McCurdy – Lawrence Berkeley Nat’l Lab

## Charge to the Subcommittee

***The subcommittee is to identify current and emerging challenges and opportunities for theoretical research within the scientific mission of Basic Energy Sciences, with particular attention paid to how computing will be employed to enable that research.  A primary purpose of the subcommittee is to identify those investments that are necessary to ensure that theoretical research will have maximum impact in the areas of importance to Basic Energy Sciences, and to guarantee that  BES researchers will be able to exploit the entire spectrum of computational tools, including the leadership class facilities contemplated by the Office of Science.***

## Schedule and Deliverables

- TIMING:  To be useful for FY 2006, we need *a report in hand by August* -- prior to the OMB budget briefing that occurs the first week in September -- final bound report by the end of January, 2005.
-  May – preliminary, substantive ideas from the committee. If the committee's findings are compelling, BES may set a very high priority for a significant budget increase in this area in FY2006.
- August -- draft report
- December/January -- final report

## The Report – Some Guidance

- Not a review of existing BES theory programs
- Prefer a report that analyzed the opportunities at a very high level and used specific examples that relate to the BES portfolio.
- NOT a report that describes the details of scientific opportunities in 25 different subspecialities.
- Provide a philosophy for investment (i.e., a portfolio of theory, modeling, high-end computation, partnering with ASCR in computational sciences, etc.).
- A high level discussion that could be packaged with any leadership-class facilities proposal that may emerge from the Office of Science.
- A roadmap for investments that will convince ... that we are ready for significant investments in at most 3 areas (not necessarily scientific fields).
- A perspective like “Quarks to the Cosmos,” -- but for BES Theory

## Subcommittee Members

- Roberto Car, Princeton U.
- Peter Cummings, Vanderbilt U.
- Jim Davenport, BNL
- Thom Dunning, ORNL/UT
- Bruce Garrett, PNNL
- Chris Greene, U. of Colorado
- Bruce Harmon, Ames Lab
- Rajiv Kalia, USC
- Kate Kirby, Harvard-Smithsonian Center
- Walter Kohn, UC-Santa Barbara

- Carl Lineberger, University of Colorado
- Bill McCurdy, LBNL
- Mike Norman, ANL
- Larry Rahn, Sandia/Livermore
- Tony Rollett, Carnegie Mellon
- Douglas Tobias, U of California, Irvine
- Stan Williams, Hewlett-Packard
- Margaret Wright, Courant Institute, NY

## Process

*Committee telephone conferences in December on strategy leading to:*
- Workshops
- Broadly solicit testimony from the community
- Develop a short series of specific questions to respondents
- E-mail solicitation via appropriate APS and ACS Divisions, and solicit experts for key contributions
- Web site for written testimony and input
- In person presentations in Chicago in April
- First subcommittee meeting, Feb.  22, Washington D.C.

## Process (cont.)

- Second subcommittee meeting to take invited testimony from community, April in Chicago
- Initial recommendations and ideas
- First writing assignments
- Subcommittee will incorporate relevant data and observations of previous reports: “SCaLeS,” “Theory and Modeling in Nanoscience”, “Complexity,” etc.
-  Preliminary “Letter Report” to BESAC and BES  early May

## What is New?  Why Ask These Questions Now?

- New Major Experimental Facilities whose Success Depends on Theoretical Support and Leadership  *Asking the Right Questions and Understanding the Answers*
- 5 Nanoscience Facilities
- Spallation Neutron Source
- Linac Coherent Light Source
- An urgent need for deeper fundamental understanding
- Basic Research for the Hydrogen Economy
- The imminent availability of powerful new tools
- Leadership Scale Computing Capability

## Proposed Principal Components of the Report

- Major Research Opportunities and Challenges for Theory and Computation in Basic Energy Sciences
- Coupling of the theory program with existing and future BES Facilities – support, collaboration and leadership
- Infrastructure, Resources and Support Necessary for a Successful BES Theory and Computation Program

## Major Research Opportunities and Challenges for BES Theory

- The task of the subcommittee is to identify a small number of major themes to describe the new opportunities for BES theory
- We must distill a complex array of new problems into: Overarching ideas,the compelling argument for addressing these issues now, and the simple, exciting story.

## The “New Conventional View” is Already Stale 

- Fundamental Questions
- E.g., Electronically excited states of molecules, large molecules and solids
- Complex Systems –
- Bridging length and time scales

## But There is a Rich Palette of Ideas from Which to Work

- Condensed Matter / Materials Physics and Engineering
- Complex phenomena - emergent properties at different length scales
-  “More is different”, “Longer is different” (rare events)
- Correlated electron systems
- Photonics and Spintronics
- Excited states
- Bio-inspired structures and processes (e.g. protein folding, membranes)
- Transformation pathways, energy landscapes
- Modeling nano structures, processes, properties, e.g., 4-probe STM, near field Optical STM,
- Quantum states, quantum information, decoherence
- New tools -> new insights on classical problems, e.g., dislocations / fatigue / crack propagation

## The List is Long

- Chemical Sciences
- Advancing Fundamental Science
- The Coupling of Structure with dynamics, and reactivity of molecules/substrates
- Relativistic effects / Heavy atom systems
- Coupling chemistry with fluid flow
- Advancing understanding of complex systems
- Catalytic systems
- Combustion systems
- Photosynthetic systems

## And Some Interesting Questions Already Emerge Naturally

- Is quantum information viable?
- All the tools that will answer this question are in the BES portfolio.
- Can nanoscience be transformed to nanotechnology?
- Is self assembly predictable and controllable?

## Connection of the Theory Program with the BES Facilities

- The traditional strategy for coupling theory to experimental programs at the BES facilities is the Blanche Dubois plan
*“...**rely on the kindness of strangers”*
- APS, ALS, NSLS, IPNS, LANSCE, HFIR, ... All have little or no associated theory program
- Users must find theoretical collaborators who are willing and already funded to work on their problems.

## Coupling of the Theory Program with the BES Facilities (cont.)

- Nanoscience Centers recognize the need for theory programs
- Their theory programs are currently being designed independently – shouldn’t they be coordinated?
- SNS theory program in development?
- In-house theory efforts at the facilities are necessary, but designing them is a challenge
- Broad spectrum of experiments at each facility
- Engaging the best talent for a service role
- In-house theory programs should be complemented by distributed theory efforts in support of specific facilities.

## Infrastructure, Resources and Support for BES Theory in the Modern Era

**What is necessary to enable the BES Theory Program to be successful in the era of leadership-scale computing?**
- A hierarchy of computational resources is necessary to express modern theory
- Leadership Scale Capability
- High Performance, Massively Parallel, Large Scale Capacity
- Local computing resources* *
- Building those facilities must be coupled with  funding the BES theory community to exploit them.

## A Distinguishing Role for DOE: Infrastructure for BES Theory (cont.)

- Support for long-term software projects – building the community codes as infrastructure for theory *and* experiment
- European programs have set an example:
- VASP/WIEN Project in Vienna, CCCP at Daresbury, R-matrix code project in the U.K.
- Another example is NIH funding of Klaus Shulten’s work on MD at Illinois (synergy with computer sciences)
- Should we have a Renewal and Expansion of the “SciDAC” style of large scale project support in BES*?*
*Only Chemical Sciences participated in SciDAC and only for $2M / yr.*