T-8 has a vigorous and wide-ranging research program. Various group activities are described below.
Beyond the Standard Model: The key feature of the Standard Model of
Particle Physics is electroweak symmetry breaking and the consequent origin
of quark and lepton masses. The Standard Model relies on an elementary
scalar field (the Higgs) to provide for electroweak symmetry breaking, but
because of the extreme fine-tuning involved most theorists believe that
Nature has chosen a more elegant method. Several alternatives have been
proposed: Supersymmetry, extra dimensions, and technicolor. Over the next
few years we should know the real answer due either to the upgraded Tevatron
experiment which has started up at Fermilab or the LHC which is scheduled for
2007 at CERN. Most of the
current activity in this part of our group is in extra dimensions. We are
studying the Randall-Sundrum model and it's generalizations as well as
"deconstructed" models of extra dimensions. We also work on particle
cosmology and have recently proposed an alternative explanation of the
recent supernova data that involves
axion oscillations
rather than an accelerating Universe. (J. Erlich, M. M. Nieto, J. Terning)
Lattice QCD: The goals of this project are to study the spectroscopy of
hadrons made up of light-light, heavy-light, and heavy-heavy quarks;
study the spectroscopy of glueballs and exotic hadrons; provide
estimates of up, down, strange, charm, and bottom quark masses;
calculate the strong coupling constant; calculate the decay constants
for light and heavy-light mesons; calculate the form factors for the
semi-leptonic decays of B and D meson; calculate the form factor for
the radiative decay of B to K* gamma; calculate the matrix elements of
the four fermion operators needed to study CP violation; investigate
the properties of QCD at finite temperature; and develop better algorithms
and improve the lattice methodology. This project is supported in part
by a DOE Grand Challenge award.
(T.
Bhattacharya,
R. Gupta)
More
info
Scaling in Biology:
Life manifests its extraordinary diversity, from microbes to whales, over a
remarkable 21 orders of magnitude in size. Surprisingly simple scaling laws
have been found to hold over this entire spectrum. For example, metabolic
rate, lifespan and rate of growth vary as a power of the size of an organism;
the exponents are simple multiples of 1/4. T-8 member G.B. West made a
breakthrough in our understanding of such phenomena: life at every scale,
driven by natural selection, is sustained by hierarchical, fractal-like
branching networks whose universal characteristics determine many of the
generic properties of living organisms.
(G. B. West)
Computational Accelerator Physics:
High-current accelerators are needed for accelerator-driven
technologies such as transmutation of radioactive waste, disposal of
plutonium, energy production, and production of
tritium. Next-generation spallation neutron sources based on similar
technology will play a major role in materials science and biological
research. Additionally, other types of accelerators such as linear
colliders (e.g., the Next Linear Collider (NLC)) and linac-driven
coherent light sources will have a significant impact on basic and
applied scientific research. All these projects require
high-resolution modeling far beyond that which has ever been performed
by the accelerator community to reduce cost and technological risk,
and to improve accelerator efficiency, performance, and
reliability. Advanced modeling of accelerators is a collaborative
project with LANSCE Division (Robert Ryne, LANSCE-1) and
is supported in part by a DOE Grand Challenge award.
(S. Habib) More info
Cosmology:
Work on the problem of the formation of large
scale structure in the universe and the associated problems of dark matter and
dark energy. Study of signatures of inflation and the cosmological effects of
extra dimensional scenarios.
(J. Erlich,
S. Habib,
Katrin Heitmann,
G. Jungman,
E.
Mottola,
J. Terning) Astrophysics:
Work on chaotic dynamics in galaxies and nontrivial self-consistent solutions
of the gravitational Vlasov-Poisson system of equations, truncated moment
hierarchy methods for approximate solutions of the Vlasov-Poisson system, and
numerical galactic dynamics on parallel supercomputers using a large
particle-mesh code [in collaboration with Tim Cleland (ACL),
Stirling Colgate (T-6), and Richard Lovelace (Cornell)].
(S. Habib,
G. Jungman)
Nonequilibrium Field Theory: Traditional applications of quantum
field theory are
restricted mainly to scattering processes and systems in thermal
equilibrium. Nonequilibrium quantum field theory is necessary to
understand initial value problems such as arise in the dynamics of the
early universe, heavy-ion collisions, and the dynamics of phase
transitions in general. Recent advances made by the Los Alamos group
include the successful implementation of the 1/N approximation in
nonequilibrium theory (including the solution of the renormalization
problem in this situation), understanding of effective dissipation in
mean field theory, and application of the new methods to disoriented
chiral condensates and to the dynamics of second order phase
transitions.
(F. Cooper,
S. Habib,
E. Mottola)
More info
Conformal Gravity:
(E. Mottola)
Quantum Mechanics:
We are working on understanding the emergence of classical properties of a
quantum system. Basically, the problem is that some of the classical
properties are defined in terms of the trajectories of the system. Thus,
for example, the Lyapunov exponents of a system are defined as the
rate of divergence of the nearby trajectories in the long time limit. The
presence of well defined trajectories is however a classical property: the
corresponding quantum system delocalizes under time evolution. We show how,
even in systems which are not otherwise interacting with their environment,
the very process of continuous observation manages to localize the system
continuously, and we find trajectories emerging in the measurement record.
(T. Bhattacharya,
S. Habib,
M. M. Nieto) Nonlinear Coherent
Structures:.
(F. Cooper,
S. Habib,
E.
Mottola)
Back to T-8 home page.
J. Terning / LANL / revised April 2002