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Computation
for the 21st Century: A New Paradigm
Dr.
Raymond L. Orbach
Director
Office of Science
U.S. Department of Energy
RAND
Graduate School
Santa Monica, CA
June 22, 2002
It is my great pleasure to congratulate
the graduates of the RAND Graduate School on
the successful completion of their doctorate.
You join a distinguished group of policy analysts
who are world leaders in their fields. Your
own research encompasses health care quality
measures in developing countries; family relationships
and their measures; effectiveness of systems
of care for at-risk children and their families;
the transition of the Italian Army towards an
All-Volunteer Force; storage and utilization
of art collections in U.S. museums; hands-on
science and student achievement; financial and
structural consequences of “carve-out”
health care services; patient experiences with
healthcare in multi-cultural settings; and the
consequences of class-size reduction policy
in California. It is a remarkably board set
of inquiries into the consequences of social
policy. Your methods of inquiry are quantitative
within a policy framework, something for which
Rand is justifiably famous. You are to be congratulated
on your achievements.
I have stressed the quantitative
element in your studies. During my scientific
career, computers were developed from the now
“creaky” IMB 701, on which I did
my thesis research in the wee hours of the morning,
to the new ASCI machines which fill rooms the
size of football fields, and use as much power
and cooling as a small city. The speed of these
latter, massively parallel machines, is now
measured in “teraflops.” For the
purpose of comparison, a “flop”
is a floating point operation per second. Don’t
worry about what a floating point means; just
think of it as an algebraic operation on your
hand held calculator. A “tera” means
a trillion, or in our everyday language a million
millions. So when I say 2 teraflops, that is
a machine capable of 2 million million operations
in one second, something that would take your
hand held calculator 57,000 years to accomplish.
The reason I made you endure
this bit of mathematics is that the teraflop
era is upon us. The DOE civilian computer has
a theoretical peak performance of 5 teraflops,
and the so-called ASCI White computer at Lawrence
Livermore has a peak performance of 12 teraflops.
This would translate to 342,000 years on your
hand held calculator, but now it takes just
1 second!
What does this mean for the U.S.
scientific community, and for you? We are now
in an era where computational simulation can
inform our approach to science, and I believe
the social science and humanities. We are now
able to contemplate exploration of worlds never
before accessible to mankind. We have used computers
to solve sets of equations, physical laws too
complicated to solve analytically. But now,
we can simulate systems to discover physical
laws for which there are no known predictive
equations. This means that we will be able to
model physical or social structures with hundreds
of thousands, or maybe even millions, of “actors”,
interacting with one another in a complex fashion.
The speed of our new computational environment
allows us to test different inter-actor (or
inter-personal) relations to see what macroscopic
behaviors can ensue. Thus, we may be able to
use simulations to determine the nature of the
fundamental “forces” or interactions
between “actors.”
This approach to understanding
complex systems is to be thought of in the same
vein as experiment and analytic theory. In science
of the 21st century, simulation and high-end
computation are equal partners with theory and
experiment.
Scientific leadership, the basis
for our economic, physical, and intellectual
prosperity depends on this triad, our being
first in each component.
Alas, we have lost the lead in
scientific computation. We are now second, and
if we continue to dally, we will be third in
this critical third leg of the triad.
Three months ago the Japanese
announced operation of the earth simulator,
a vast computer with a peak speed of 40 teraflops,
3 times the fastest U.S. machine’s theoretical
peak performance. But there is more: the architecture
of their machine was structured to solve a class
of problems, climate change to begin with. Their
sustained speed was close to 20 teraflops, or
about 50% efficiency. The fastest U.S. computers
exhibit an efficiency of approximately 10% because
the United States has adopted a “one size
fits all” philosophy. By some estimates,
this leads to a lag of a factor of 40-50 for
the National Center for Atmospheric Research’s
climate model.
The full story is worse. Not
only can climate change models run at these
efficiencies, the Japanese have very recently
shown similar capacities in fluid and plasma
dynamics calculations.
Bluntly put, we are out of business
in some critical areas of computational science.
The earth simulator works on a grid 10 km on
a side for climate models, while U.S. computers
do no better than 100 km on a side. This means
that U.S. simulations average over microclimates
— mountains and coastal effects, river
flow, cloud and storm systems, or hurricane
storms. Averaging means that our models cannot
credibly predict large scale fluctuations in
climate change, critical for long-term drought
and flood predictions.
What does it mean to lose scientific
leadership, to be #2? There is a qualitative
difference for large scale computational simulations
as compared to conventional calculations –
they do not travel. The great scientific discoveries
will take place in Kanazawa, Japan, and not
here.
What can we do about it? Should
we do anything about it? I believe our country
cannot afford to be second best, to be “good
enough.” Our economy, our intellectual
environment, literally our national security
depends upon our scientific primacy. What very
bright student will want to enter a field where
we are #2? And what about Europe? They are already
purchasing Japanese machines. Are we to be #3?
This does not only apply to climate
change simulations. Also at risk is our leadership
in nanoscience, accelerator design, astrophysics,
combustion, materials science, and fusion energy
research.
Biology will not be far behind:
simulations can significantly aid our understanding
of the systematics of cellular function. And
the social sciences – Are systems approaches
through simulations at hand?
The United States needs to face
up to our dilemma, a construct of our own doing.
We must move away from the pretense that a single
computational architecture can work for all
of our scientific needs.
The United States must embrace
the concept of a diversity of computational
architecture to address a variety of applications.
We need to begin with the science, and scientists,
starting with the problems which we wish to
address. Bring to the table the computer scientists,
the applied mathematicians, those who are good
at algorithms, together with the chip makers
and computer architects, those who can produce
the computers devised for the scientific problem
at hand.
The result will be machines enabling
us to solve scientific and social problems of
great importance. We shall be able to investigate
systems of great complexity, and understand
predictive laws for their behavior. We will
free ourselves of the bounds of one-at-a-time
processes, and learn the rules of collective
behavior on a scale previously unknown. The
opportunities are immense. We cannot afford
to be second or third in this pursuit. We have
the will and the capacity to fix this.
As a product of the Sputnik generation,
I can personally attest to the vigor and vitality
of the U.S. response. It is now incumbent upon
us to repeat this dedication in this new era
of computnik, to regain our scientific leadership
and primacy.
You RGS graduates are first class.
We need to provide you with a computational
platform of comparable quality.
Graduates, I congratulate
and salute you. Our hearts and very best wishes
are with you. Good luck and God speed.
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