List of invited speakers & talk titles
- Speaker: Mark Alber, University of Notre Dame
Title: Multiscale modeling in biology
Abstract: A multiscale model of blood clot formation will be described, which
combines a detailed tissue factor pathway submodel of blood
coagulation, a blood flow submodel and a stochastic discrete cell
submodel [1,2]. It will be shown that low levels of FVII in blood
result in a significant delay in thrombin production demonstrating
that FVII plays an active role in promoting clot development at an
early stage. We will also describe a new subcellular element method
for simulating cellular blood components. In addition, multiscale
models of bacterial swarming will be discussed [3].
- Xu, Z., J. Lioi, J. Mu, X. Liu, M.M. Kamocka, E.D. Rosen, D.Z.
Chen and M.S. Alber [2010], A Multiscale Model of Venous Thrombus
Formation with Surface-Mediated Control of Blood Coagulation
Cascade, Biophysical Journal 98, 9, 1723-1732.
- Xu, Z., Chen, N., Shadden, S., Marsden, J.E., Kamocka, M.M.,
Rosen, E.D., and M.S. Alber [2009], Study of Blood Flow Impact on
Growth of Thrombi Using a Multiscale Model, Soft Matter 5, 769-779.
- Wu, Y., Jiang, Y., Kaiser, D., and M. Alber [2009], Periodic
reversal of direction allows Myxobacteria to swarm, Proc. Natl.
Acad. Sci. USA 106 4 1222-1227 (featured in the Nature News, January
20th, 2009, doi:10.1038/news.2009.43).
- Speaker: Phil Anderson, Princeton University
Title: What is wrong with QMC?
Abstract: It is becoming increasingly clear that the underlying order
which changes at a quantum critical point in many of the strong
correlation problems--for example, cuprate superconductiivity--is the
size and shape of the Fermi surface. The excitations which represent
Fermi surface fluctuations are the tomographic Tomonaga bosons
invented by Luther, Haldane, and others, which are poorly represented
by computational schemes with rigid boundary condiitions and rigidly
fixed particle number such as quantum Monte Carlo. Thus such schemes
do not faithfully represent just the critical fluctuations around the
most relevant quantum critical point.
- Speaker: Eva Andrei, Rutgers University
Title:Electronic
properties of graphene
Abstract: Graphene, a one-atom thick
membrane of crystalline carbon possesses extraordinary electronic
properties which make it a prime candidate for novel nano-electronic
devices, at the same time raising the prospect to observe phenomena
hitherto unseen in bench top experiments. I will present scanning
tunneling microscopy1,2 and transport experiments that provide access
to the dynamics of the charge carriers in this material and give new
insights their unique world. The findings include direct observation
of the Landau level energy spectrum1,2, observation of the fractional
quantum Hall effect3 and a magnetically induced insulating phase.
1. X. Du, I. Skachko, F. Duerr, A. Luican and E. Y. Andrei, Nature
462, 192, (2009)
2. G. Li et al Nature Physics 6, 109 ( 2009)
3. G. Li, A. Luican, E.Y. Andrei, Phys. Rev. Lett 102, 176804
(2009)
- Speaker: Eli Ben-Naim, Los Alamos
Title: Strong Mobility in Disordered Systems
Abstract: TBA
- Speaker: Nihat Berker, Sabanci University
Title: Anisotropy Effects and Impurity Induced Antiferromagnetism:
Renormalization-Group Theory of d=3 Electronic Models
Abstract: TBA
- Speaker: Lesser Blum, Rutgers University
Title: Hyperscaling theory for charged systems
Abstract
- Speaker: Leonid Bunimovich, Georgia Tech.
Title: Which hole is
leaking the most: Topological approach to open systems and dynamical
networks
Abstract: A natural question on how a process of escape
depends on a position of a hole in a phase space seems to be
overlooked in the theory of open dynamical systems. An answer to this
question allows to reveal a new role of periodic orbits in the
evolution of dynamical systems, to classify dynamically the nodes
(elements) of dynamical networks and, most surprisingly, to realize
that it is possible to make not only traditional (asymptotic in time
as time tends to infinity) but finite time predictions of the behavior
of dynamical systems.
1.Afraimovich V.S. and Bunimovich L.A., Dynamical networks: interplay of topology, interactions and local dynamics, Nonlinearity, v.19 (2007) 1761-71
2.Afraimovich V.S. and Bunimovich L.A., Which hole is leaking the most: a topological approach to study open systems, Nonlinearity, v.23 (2010) 643-56
3.Bunimovich L.A. and Yurchenko A. Where to place a hole to achieve fastest escape rate, Israel J. Math, at press (asXiv:0811.4438)
- Speaker: Curtis Callan, Princeton University
Title: Deep sequencing, mutual information and the thermodynamics of
gene regulation
Abstract: The regulation of gene expression is thought to be largely
governed by the binding thermodynamics of regulatory proteins. I will
argue that high-throughput sequencing, combined with a novel analysis
technique based on mutual information, can give a precise
thermodynamic account of gene regulatory function. I will describe the
application of this method to the bacterial lac promoter, showing how
one can infer the in vivo interaction energy between two proteins in
the cell from sequence data alone.
- Speaker: Roberto Car, Princeton University
Title: Quantum protons and hydrogen bonds
Abstract: Near room temperature the momentum distribution of the protons
participating in hydrogen bonds is quite different from the classical
Boltzmann distribution. Thus the equilibrium structure of systems like
liquid water is directly influenced by quantum mechanics. When the
proton environment is nearly harmonic semi-classical approximations
are possible, but in presence of tunneling, such as e.g. in ice under
high pressure, a full quantum treatment is needed. In that case the
interplay between quantum tunneling and ice-rule correlations among
the protons leads to distinct observable effects.
- Speaker: Paul Chaikin, NYU
Title: Self-Replication Without
Life
Abstract: We want to make a "non-biological" system which
can self-replicate. The idea is to design particles with specific and
reversible and irreversible interactions, introduce seed motifs, and
cycle the system in such a way that a copy is made. Repeating the
cycle would double the number of offspring in each generation leading
to exponential growth. Using the chemistry of DNA either on colloids
or on DNA tiles makes the specific recognition part easy. In the case
of DNA tiles we have in fact replicated the seed at least to the third
generation. The DNA linkers can also be self-protected so that
particles don't interact unless they are held together for sufficient
time-nano-contact glue. We have also designed and
produced colloidal particles that use novel "lock and key"
geometries to get specific and reversible physical interactions.
- Speaker: Arup Chakraborty, MIT
Title: Why people with certain genes can control hiv without therapy:
from statistical mechanics to the clinic
Abstract: TBA
- Speaker: Lincoln Chayes, UCLA
Title: The McKean-Vlasov
Equation in Finite Volume
Abstract: The McK-V system is a
nonlinear diffusion equation with a nonlocal nonlinearity
provided by convolution. Recently popular in a variety of
applications, it enjoys an ancient heritage as a basis for
understanding classical fluids in equilibrium and near
equilibrium. The model is discussed in finite volume where, on the
basis of the physical considerations, the correct scaling (for the
model itself) is identified. For dimension two and above and in large
volume, the equilibrium phase structure of the model is completely
elucidated in (somewhat disturbing) contrast to dynamical
results. This is joint work with V. Panferov.
- Speaker: Bernard Chazelle, Princeton University
Title: The total S-Energy: An analytical tool for multiagent dynamics
Abstract:
I discuss a new analytical device for the study of multiagent agreement systems. The "total s-energy" of an
infinite sequence of graphs embedded in Euclidean space
is a Dirichlet series encoding all of the edge lengths.
It generalizes both the graph Laplacian and the Riesz s-energy of points on a sphere.
I will discuss how analytical properties of
the total s-energy leads to bounds on the convergence
rates of several classical agreement systems, including
opinion dynamics, synchronization, and flocking.
The total s-energy draws its power from
its ability to handle products of stochastic matrices
algorithmically "without looking inside the matrices."
This work is part of a larger project to explore
the benefits of viewing dynamical systems as "natural algorithms."
- Speaker: Eugene Chudnovsky, Lehman College
Title: Self-organized tunneling dynamics of molecular nanomagnets
Abstract: Magnetic moments of high-spin molecules can reverse their orientation through quantum tunneling [1]. Many-body quantum dynamics of crystals made of such molecules involves self-organization of magnetic dipoles, aimed at maintaining resonant tunneling condition [2]. Theory and experiments in this field will be reviewed.
- E. M. Chudnovsky and J. Tejada, Lectures on Magnetism (Rinton Press, Princeton, 2006).
- D. A. Garanin and E. M. Chudnovsky, Phys. Rev. Lett. 102, 097206 (2009).
- Speaker: P. Debenedetti, Princeton University
Title: Thermodynamic and kinetic models of the appearance and
amplification of biological chirality
Abstract
- Speaker: Robert Ecke, Los Alamos
Title:Unstable diffusion layers: From thermal convection and material
dissolution to sequestration of CO2
Abstract: TBA
- Speaker: Fereydoon Family, Emory University
Title: Physics of Age-Related Macular Degeneration
Abstract: TBA
- Speaker: Jerry Gollub, Haverford College
Title: Statistical Mechanics of Swimming Microorganisms
Abstract: TBA
- Speaker: F.D.M. Haldane, Princeton University
Title: Dissipationless "Hall viscosity" and its relation to
incompressibility of quantum Hall fluids
Abstract
- Speaker: Tom Kennedy, University of Arizona
Title: Renormalization group maps for Ising models in lattice gas variables
Abstract: TBA
- Speaker: Michael Kiessling, Rutgers University
Title: On the N dependence of classical and quantum N-body ground
state energies
Abstract
- Speaker: Paul Krapivsky, Boston University
Title: Kinetics of cell division
Abstract: TBA
- Speaker: Robert Kohn, Courant Institute
Title: Surface relaxation below the roughening temperature: steps,
pde's, and self-similarity
Abstract:TBA
- Speaker: Herbert Levine, University of California,San Diego
Title: Information limits on eukaryotic chemotaxis
Abstract: Many types of eukaryotic cells are able to detect chemical gradients
and move accordingly (Parent and Devreotes, 1999). Unlike the case for bacteria, these cells are
large enough for the gradient detection to rely on differential
receptor binding probabilities on the cell membrane. It is not yet
understood how this noisy input data (Rappel and Levine, 2008; Endres and Wingreen, 2008) is processed by the cell to make the
motion decision; thus we cannot a priori predict the detection
threshold, the response kinetics and the plasticity to changing
stimuli. This talk will focus on recent experimental and theoretical
work (Fuller et al, submitted) which shows that at small gradients,
cell performance is limited primarily by sensor noise.
REFERENCES
Parent CA, Devreotes PN (1999) A cell's sense of direction. Science 284: 765-770
Rappel WJ, Levine H (2008) Receptor noise limitations on chemotactic sensing. Proc Natl Acad Sci U S A 105: 19270-19275
Endres RG, Wingreen NS (2008) Accuracy of direct gradient sensing by single cells. Proc Natl Acad Sci U S A 105: 15749-15754
Fuller, D et al, External and internal constraints to eukaryotic chemotaxis, under review
- Speaker: Mike Lipkin, Columbia University/Katama Trading, LLC
Title: Hard-To-Borrow Stocks. Why restrictions on shorting lead to
higher prices, higher volatilities, crashes and bubbles!
Abstract: Restrictions on the shorting of stocks have the paradoxical effect
of increasing volatilities and prices. We demonstrate this with a simple but
very rich stochastic model which reproduces market prices and allows
predictions about asset bubbles as well!
- Speaker: Jon Machta, University of Massachussetts
Title:Monte Carlo methods for rough free energy landscapes
Abstract: TBA
- Speaker: John Marko, Northwestern University
Title: Linking topology of large DNA molecules
Abstract: Double helix DNA molecules, the carriers of genetic instructions in cells,
are strongly affected by their topological properties. Two distinct and
biologically important types of linking are associated with double helix
DNAs: 'internal' linking of the two strands of individual double helices,
and 'external' linking of separate double helix DNAs. Constraint of
internal linking gives rise to internal torsional stress and supercoiling
of circular DNAs. I will discuss an additional important but often
ignored constraint associated with DNA supercoiling as it appears to occur
in vivo. I will also discuss 'external' linking of separate double
helices, which is a likely outcome of DNA replication, and which must be
eliminated by the cell in order to separate duplicated DNAs. I will
present an argument based on scaling laws for linking number fluctuations
of flexible polymers to address how cells manage to eliminate
entanglements (and knots) from their long chromosomal DNAs.
- Speaker: Michael Monastyrsky,ITEP,Moscow
Title:Duality transformations for Non-Abelian Spin Systems
Abstract: The Classical Kramers Wannier(KW) Duality is a special
Symmetry which relates low-temperature and high-temperature phases in
the planar Ising model. Generalization of this transformation to Spin
Models with non-Abelian Symmetry is essential for many problems in
Statistical Physics and Field theory. In my talk I present new results
which solve this problem for finite and compact groups and different
two-dimensional lattices,including so called Hecke graphs.
- Speaker: David Nelson, Harvard University
Title: Life at Low
Reynolds Number
Abstract:
As an example of life at high Reynolds
number, we investigate the dynamics of the Fisher equation for the
spreading of micro-organisms subject to both turbulent advection and
diffusion.[1] The effective advecting velocity field turns out to be
compressible in a number of important circumstances. For strong
enough turbulence, bacteria, for example, track, in a quasilocalized
fashion (with remarkably long persistence times), sinks in the
turbulent field. An important consequence is a large reduction in the
carrying capacity of the fluid medium. We analytically determine the
regimes where this quasi-localized behavior occurs and test our
predictions by numerical simulations.
[1] R. Benzi and
D. R. Nelson, Physica D 238 2003 (2009)
- Speaker: Charles Newman, Courant Institute
Title: Ground states of the 2D Edwards-Anderson spin glass
Coauthors: Louis-Pierre Arguin, Michael Damron, Chuck Newman*, Dan Stein
Abstract: This is joint work with Louis-Pierre Arguin,
Michael Damron and Dan Stein. It is an open problem
to determine the number of infinite-volume ground states
in the Edwards-Anderson (nearest neighbor) spin glass model
on Zd for d ≥ 2 (with, say mean zero Gaussian
couplings). This is a limiting
case of the problem of determining the number of extremal
Gibbs states at low temperature. In both cases, there
are competing conjectures for d ≥ 3, but no complete
results even for d=2. I report on new results which go
some way toward proving that (with zero external field,
so that ground states come in pairs, related by a global
spin flip) there is only a single ground state pair (GSP).
Our result is weaker in two ways: First, it
applies not to the full plane Z2, but to a half-plane.
Second, rather than showing that with probability one (according to the quenched random coupling realization J)
there is a single GSP, we show that there is a natural
joint distribution on J and GSP's such that
with probability one, the conditional distribution on GSP's
given J is supported on only a single GSP. The methods
used are a combination of percolation-like geometric
arguments together with translation invariance (in one
of the two coordinate directions of the half-plane)
and employ as a main tool the "excitation metastate"
which is a probability measure on GSP's and on how
they change as one or more individual couplings vary.
Reference: arXiv:0911.4201
- Speaker: Michele Parinello, ETH, Zurich
Title: Advanced sampling methods
Abstract: TBA
- Speaker: David Pine, NYU
Title: Non-equilibrium phase transitions and random ordering in driven suspensions of rods
Abstract: TBA
- Speaker: Karen Rabe, Rutgers University
Title: Spin-lattice coupling in magnetic perovskite thin films and
superlattices
Abstract: In the search for new ferromagnetic-ferroelectric
multiferroic materials, one key challenge is to maximize the coupling
between the magnetization and the ferroelectric polarization. In this
talk, I will briefly review several mechanisms by which such coupling
can occur, and present first-principles results for prototypical
systems. First, I will discuss the large spin-phonon coupling in
SrMnO3. First principles calculations show that this coupling results
in an epitaxial-strain-induced ferromagnetic-ferroelectric
state. This occurs by the mechanism introduced earlier for EuTiO3,
though in SrMnO3, with magnetic ions on the B site, the magnetic and
ferroelectric phases persist to much higher temperatures. Next, I will
discuss the spinel-structure oxide CdCr2O4 and the perovskite
BiMnO3/BiFeO3 nanocheckerboard, in which magnetic frustration in
principle allows perturbations that change the structure to drive
phase transitions in magnetic ordering. Finally, I will present
preliminary results on ferroelectrically-induced weak ferromagnetism
in perovskite superlattices identified via the
crystal-chemical/symmetry criteria proposed by Craig Fennie.
- Speaker: Vered Rom-Kedar, Weizmann Institute
Title: Models of the innate immune system: theory and medical implications
Abstract: Simple models of the innate immune system teach us much
about the development of infections when the bone-marrow function is
damaged by chemotherapy. The results depend only on robust properties
of the underlying modeling assumptions and not on the detailed models.
Moreover, such models may lead to improved treatment strategies for
neutropenic patients [1,2,3].
- R. Malka, E. Shochat and V. Rom-Kedar; Bistability and Bacterial
Infections. PLoS ONE, 2010, to appear.
- E. Shochat and V. Rom-Kedar; Novel strategies for G-CSF treatment
of high-risk severe neutropenia suggested by mathematical modeling,
Clinical Cancer Research 14, 6354-6363, October 15, 2008.
- E. Shochat, V. Rom-Kedar and L. Segel; G-CSF control of
neutrophils dynamics in the blood, Bull. Math. Biology , 69(7),
2299-2338, 2007.
- Speaker: James Sethna, Cornell University
Coauthors: Y.S. Chen, W. Choi and S. Papanikolaou
Title: Bending Crystals: The evolution of self-similar dislocation
structures
Abstract: TBA
- Speaker: Eugene Shaknovich, Harvard University
Title: Dynamics of evolution and adaptation:Insights from ab initio multiscale models
Abstract: TBA
- Speaker: David Vanderbilt, Rutgers University
Title: Orbital magnetoelectric effects and topological insulators
Abstract: I will discuss two kinds of topological insulators. First, a
"Chern insulator" is one in which the "Chern number," defined in
terms of the integral of the Berry curvature over the Brillouin
zone, is non-zero. Such a system is also known as a "quantum Hall
insulator" because it would exhibit a quantum Hall effect in the
absence of a magnetic field (possibly at room temperature). While
no examples are yet known to exist in nature, theoretical models of
Chern insulators are readily constructed (Haldane first did so two
decades ago [1]), and there is no known reason why they should not
exist. I shall mention some of our earlier work on the properties
of such prospective Chern insulators [2-3], and speculate about
prospects for discovering experimental realizations. Second, there
has been a great deal of interest recently in another kind of
topological insulator, the so-called "Z2-odd" insulator. Such a
system can be conceptualized by imagining that a spin-up system of
electrons having Chern number $+1$ coexists with a spin-down system
having Chern number $-1$ in such a way that the system as a whole
has total Chern number zero and obeys time-reversal (T) symmetry.
Even when the spin-orbit interaction is turned on, the system
carries a topological even-or-odd (Z2) label. Almost all known
insulators are Z2-even, but great excitement has surrounded the
recent realization that some materials, such as Bi(x)Sb(1-x) [4],
Bi2Te3 [5], and related systems, are Z2-odd. We have developed a
theory of the orbital contribution to the linear magnetoelectric
effect (or equivalently, to the surface Hall conductivity) in
magnetoelectric insulators having broken T symmetry [6]. The
theory exhibits many attractive analogies to the theory of
polarization, and involves a higher-order kind of Chern index than
the one discussed above. Interestingly, our theory predicts that
an insulator with T symmetry need not have a vanishing
magnetoelectric coupling; instead, precisely in the case of a
Z2-odd insulator, it must have a half-quantum value (see also
[7]). Essentially this means that the surface of a Z2-odd
topological insulator, if it is gapped by a T-breaking
perturbation, will exhibit a half-integer quantum Hall effect.
- F.D.M. Haldane, Phys. Rev. Lett. 61, 2015 (1988).
- T. Thonhauser and D. Vanderbilt, Phys. Rev. B 74, 235111
(2006).
- S. Coh and D. Vanderbilt, Phys. Rev. Lett. 102, 107603 (2009).
- D. Hsieh et al., Nature 452, 970 (2008).
- Y.L. Chen et al., http://arxiv.org/abs/0904.1829.
- A.M. Essin, J.E. Moore, and D. Vanderbilt, Phys. Rev. Lett.
102, 146805 (2009).
- X.L. Qi, T.L. Hughes and S.-C. Zhang, Phys. Rev. B 78, 195424
(2008).
- Speaker: David Weitz, Harvard University
Title: Fast Crystals and Strong Glasses
Abstract: This talk presents new results for colloidal crystals and
glasses. By investigating the morphology of crystal nuclei, we
establish the importance of an entropic term in the free energy
reflecting the number of morphologies of the nuclei. This modifies
the nucleation rate, and accounts for the much faster rate of
nucleation observed experimentally when compared to predictions. We
also show that the behavior of deformable colloidal particles is
reminiscent of molecular glasses with different structures, mimicking
the range of fragilities reported for molecular systems.
- Speaker: Victor Yakovenko, University of Maryland, College Park
Title: Statistical Mechanics of Money, Income, and Wealth
Abstract: This talk will review the progress in applications of
statistical physics to probability distributions of money, income, and
wealth in a society [1]. Using analogy between the probability
distributions of energy in physics and money in economics, I argue
that the distribution of money should follow the exponential
Boltzmann-Gibbs law for certain classes of models with interacting
economic agents [2]. Analysis of the empirical data shows that income
distribution in the USA has a well-defined two-class structure [3].
The majority of the population (about 97%) belongs to the lower class
characterized by the exponential ("thermal") distribution [4]. The
upper class (about 3% of the population) has the Pareto power-law
("superthermal") distribution, whose share of the total income expands
and contracts dramatically following the bubbles and busts in
financial markets [5]. When debt is included in the statistical
models, it destabilizes the Boltzmann-Gibbs distribution in the
absence of an intrinsic mechanism for limiting debt [1]. As a result,
the nominal wealth growth of the upper class largely comes from the
debt growth of the lower class, until the economy collapses under the
burden of excessive debt. I will also briefly discuss the
distribution of energy consumption per capita around the world and
show that it also follows the exponential Boltzmann-Gibbs law [6].
The data show how globalization of the world economy affects the
inequality of energy consumption. More references can be found at the
Web site [7].
References
- V. M. Yakovenko and J. B. Rosser, Jr., "Colloquium: Statistical Mechanics of Money, Wealth, and Income", Reviews of Modern Physics 81 (2009) 1703.
- A. Dragulescu and V. M. Yakovenko, "Statistical mechanics of money", The European Physical Journal B 17 (2000) 723.
- A. Dragulescu and V. M. Yakovenko, "Exponential and power-law probability distributions of wealth and income in the United Kingdom and the United States", Physica A 299 (2001) 213.
- A. Dragulescu and V. M. Yakovenko, "Evidence for the exponential distribution of income in the USA", The European Physical Journal B 20 (2001) 585.
- A. C. Silva and V. M. Yakovenko, "Temporal evolution of the 'thermal' and 'superthermal' income classes in the USA during 1983-2001", Europhysics Letters 69 (2005) 304.
- A. Banerjee and V. M. Yakovenko, "Universal patterns of inequality", submitted to New Journal of Physics, arXiv:0912.4898.
- Econophysics Web page of Victor Yakovenko, http://www2.physics.umd.edu/~yakovenk/econophysics/