Statistical Mechanics Conference Main Page

100th Statistical Mechanics Conference

RUTGERS, THE STATE UNIVERSITY OF NEW JERSEY
HILL CENTER, ROOM 114
SUNDAY, MONDAY AND TUESDAY
DECEMBER 13-18, 2008

Short talk schedule

Below please find the schedule of short talks. [Session A1, Monday afternoon - 5:10pm-5:45pm, Session A2, Monday morning, 7:30am-9:50am, Session B, Tuesday morning - 7:30am-10:30am and Session C on Tuesday afternoon, 5:00pm-6:30pm (Session C will emphasize discreet mathematics)].

Session A1

A1 - T. Einstein, University of Maryland
Title: Touching Steps on Vicinal Surfaces: Corrections to the Fermion Picture
Coauthors: Kwangmoo Kim and Rajesh Sathiyanarayanan
Abstract: Steps on vicinal (misoriented) crystal surfaces are often modeled as the world lines of fermions in (1+1)D. Analogous to the Calogero-Sutherland model, the terrace-width distribution can be well described by a generalization of the Wigner surmise. However, although steps cannot cross, they can touch (as multilayer-height steps). We describe the consequent corrections, showing that for energetically non-interacting steps, this effect leads to an effective, finite-size dependent attraction between steps.

A2 - A.N. Berker, Koc University
Title: Quenched-Vacancy Induced Spin-Glass Order
Coauthors: G. Gulpinar
Abstract: The ferromagnetic phase of an Ising model in d = 3, with any amount of quenched antiferromagnetic bond randomness, is shown to undergo a transition to a spin-glass phase under sufficient quenched bond dilution.[1] This general result, demonstrated here with the numerically exact renormalization-group solution of a d = 3 hierarchical lattice, is expected to hold true generally, for the cubic lattice and for quenched site dilution. Conversely, in the ferromagnetic-spinglass-antiferromagnetic phase diagram, the spin-glass phase expands under quenched dilution at the expense of the ferromagnetic and antiferromagnetic phases. In the ferro-spinglass phase transition induced by quenched dilution reentrance is seen, as previously found for the ferro-spinglass transition induced by increasing the antiferromagnetic bond concentration.

[1] G. Gulpinar and A.N. Berker, arXiv:0811.0025v1 [cond-mat.dis-nn] (2008).

A3 - D. Chandler, University of California, Berkeley
Title:Corresponding states of transport behavior of structural glass forming liquids
Coauthors: Yael Elmatad and Juan P. Garrahan (U of Nottingham)
Abstract: Seemingly varied transport behaviors of all published data on fragile glass formers can be collapsed to a single parabolic function. This work is posted at arXiv:0811.2450.

A4 - D.J. Bergman, Tel Aviv University
Title: Critical points of magnetotransport in a composite medium
Coauthors: N/A
Abstract: Some new critical points have been found in the macroscopic Ohmic resistivity of composite conductors. They occur when the system is subjected to a magnetic field that is strong enough so that the Hall resistivity is greater than the Ohmic resistivity in at least one constituent. These critical points were found via an appropriate extension of the Bruggeman self-consistent effective medium approximation.

A5 - P. Cvitanovic, Georgia Tech.
Title: Geometry of wall-bounded turbulence
Coauthors: J.F. Gibson, J. Halcrow and D. Viswanath
Abstract: In the world of moderate Reynolds number, everyday turbulence of fluids flowing across planes experiments are today almost as detailed as the numerical simulations, DNS is yielding exact numerical solutions, and dynamical systems visualization of turbulent fluid's state space geometry is unexpectedly elegant.
We shall take you on a 3 minute tour of this newly breached, hitherto inaccessible territory.

A6 - L. Thomas, University of Virginia
Title: Stationary state for a stochastic wave equation modeling heat flow
Coauthors: Yao Wang
Abstract: We consider a stochastic wave equation with bounded non-linearity modeling heat flow between reservoirs maintained at different temperatures. The noise is low-dimensional. We show that the equation with ultraviolet cut-off has a unique invariant measure. We establish a kind of tightness of these cut-off measures as the cut-off is removed, in particular, that given Fourier modes of the field have variances uniformly bounded in the cut-off.

Session A2

A1 - D. Dong, Hamline University
Title: Refined mean-field approach to TASEP with inhomogeneity
Coauthors: Royce K.P. Zia, Beate Schmittmann
We investigate the totally asymmetric simple exclusion process (TASEP) with a single defect site with hopping rate $q$ < 1, at the edge of the system and particles occupying $\ell$ lattice sites. Using two different mean-field approximations, we analyze the behavior of the steady state current $J$ in the presence of the defect as a function of entry rate $\alpha$ and $q$. In good agreement with Monte Carlo simulations, these two methods bring insight to understanding the significance of having one or a cluster of slow codons (unit of messenger RNA, template of protein synthesis) immediately after initiation during protein synthesis. Related work is published in J. Phys. A: Math. Theor. 42 (2009) 015002.

A2 - L. Shaw, College and William and Mary
Title: Vaccine control for epidemics on adaptive networks
Coauthors: Ira Schwartz
Abstract: We study an epidemic model for disease spread on an adaptive network. Individuals are assumed to adapt their social contacts to minimize their risk of disease. Non-infected nodes rewire their connections away from infected nodes to connect instead to other non-infected nodes, and the disease follows an SIS (susceptible-infected-susceptible) dynamics. We add Poisson distributed vaccination of susceptibles. Disease extinction rates using vaccination are found for both adaptive and static networks. We show that vaccine control is much more effective in adaptive networks than in static networks due to an interaction between the rates of adaptive network rewiring and vaccine application.

A3 - R. Akiyama, Kyushu University
Title: Kirkwood Superposition Approximation in Hard Sphere Mixture: A Study Using the OZ-HNC Theory
Coauthors: Yasuhito Karino
Abstract: The three dimensional reduced density profiles in the vicinity of two hard spheres immersed in binary hard sphere mixture are calculated using the OZ-HNC theory. We calculate them through two ways. One is the 3D-OZ-HNC theory and the other is the 1D-OZ-HNC theory with the Kirkwood superposition approximation. The approximation becomes accurate, as the size ratio increases.

A4 - T. Antal, Harvard University
Title: Exciting Hard Spheres
Coauthors: P. L. Krapivsky and S. Redner
Abstract: We investigate the collision cascade that is generated by a single moving particle in a static and homogeneous hard-sphere gas. We argue that the number of moving particles at time t grows as t^xi and the number collisions up to time t grows as t^eta, with $xi-/(d+2), eta=2(d+1)/(d+2), and d the spatial dimension. These growth laws are the same as those from a hydrodynamic theory for the shock wave emanating from an explosion. Our predictions are verified by molecular dynamics simulations in d=1 and 2. For a particle incident on a static gas in a half-space, the resulting backsplatter ultimately contains almost all the initial energy.

A5 - W. Ellenbroek, University of Pennsylvania
Title: Lateral segregation in a lipid monolayer due to lipid-counterion electrostatics
Coauthors: David A. Christian, Ilya Levental, Andrea J. Liu, and Paul A. Janmey
Abstract: Multivalent ions such as calcium play an important role in soft matter and biological systems. This role cannot be captured by a mean field treatment of the electrostatics such as the Poisson-Boltzmann equation, which neglects, for example, the fact that Ca$^{2+}$-ions can mediate attractions between negatively-charged objects. We will briefly discuss a recent experiment that showed that such attractions lead to phase separation of charged and neutral lipid molecules in mixed lipid monolayers, and our first steps towards a theoretical model of this system.

A6 - S. Durukanoglu, Istanbul Technical University
Title: Molecular Static Calculations of Cu Nanowires: The Effect of Local Strain and Cross-sectional Area Coauthors: Berk Onat, Mine Konuk, *Sondan Durukanoglu,and Gulay Dereli Abstract: We have calculated the activation energies for several single atom and vacancy diﬀusion processes on Cu nanowires with the axial orientation of <100>, using the nudged elastic band technique based on the interaction potential obtained from the embedded atom method. It is shown that the dimer-initiated local strain and its relief at the transition state have a signiﬁcant eﬀect on the characteristics of self-surface dif- fusion mechanisms on nanowires. Contrary to the case of cylindrical multishell-type Cu nanowires, the vacancy formation energy for rectangular nanowires is maximum in the core region and is nearly zero at the corner of the nanowire. In addition, the activation energy barriers for the vacancy diﬀusion processes taking place in the core region are found to be higher than those occurring near the corner of the nanowire. Our calculations further show that the vacancy diﬀusion processes taking place near the corner of the wire are dictated by the lower coordination of the surrounding atoms.

A7 - M.L. Manning, Princeton University
Title: Aging in a shear transformation zone model of amorphous solids
Coauthors: Joerg Rottler
Abstract: Comparisons between simulation data for an aging binary Lennard Jones glass and numerical solutions to the Shear Transformation Zone (STZ) model for amorphous solids indicate that an effective temperature STZ theory is able to capture many features of an aging LJ glass. In addition, the data provide a strong set of constraints on the STZ model. One unexpected constraint is that the glass transition temperature determined by the onset of a yield stress in the LJ glass is very different from the thermal temperature at which local structural rearrangements cease.

A8 - O. Ozcelik, Koc University
Title: The Blume-Emery-Griffiths Spin Glass and Inverted Tricritical Points
Coauthors: A. Nihat Berker
Abstract: The Blume-Emery-Griffiths spin glass is studied by renormalization-group theory in d=3.[1] The boundary between the ferromagnetic and paramagnetic phases has first-order and two types of second-order segments. This topology includes an inverted tricritical point, first-order transitions replacing second-order transitions as temperature is lowered. The phase diagrams show disconnected spin-glass regions, spin-glass and paramagnetic reentrances, and complete reentrance, where the spin-glass phase replaces the ferromagnet as temperature is lowered for all chemical potentials.

[1] V.O. Ozcelik and A.N. Berker, Phys. Rev. E 78, 031104 (2008).

A9 - C.N. Kaplan, Brandeis University
Title: Infinitely Robust Order and Local Order-Parameter Tulips in Apollonian Networks with Quenched Disorder
Coauthors: M. Hinczewski and A.N. Berker
Abstract: For a variety of quenched random spin systems on an Apollonian network, including ferromagnetic and antiferromagnetic bond percolation and the Ising spin glass, we find the persistence of ordered phases up to infinite temperature over the entire range of disorder.[1] We develop a renormalization-group technique that yields highly detailed information, including the exact distributions of local magnetizations and local spin-glass order parameters, which turn out to exhibit, as function of temperature, complex and distinctive tulip patterns.

[1] C.N. Kaplan, M. Hinczewski, and A.N. Berker, arXiv:0811.3437v1 [cond-mat.dis-nn] (2008).

A10 - G. Tellez, Universidad de los Andes
Title: Statistics of domains and the Wigner surmise
Coauthors: D. L. Gonzalez
Abstract: We study one-dimensional or quasi one-dimensional out of equilibrium systems which present domain formation. For instance, we consider a quasi one-dimensional gas with two species of particles under the action of an external field which drives each species in opposite directions [1]. Another system of interest is a one-dimensional spin system with nearest neighbor interactions also under the influence of an external driving force [2]. Both systems show a dynamical scaling with domain formation. The statistical behavior of these domains is compared with models based on the coalescing random walk and the interacting random walk. We find that the scaling domain size distribution of the gas and the spin systems is well fitted by the Wigner surmise, which lead us to explore a possible connection between these systems and the circular orthogonal ensemble of random matrices [3, 4].

J. Mettetal, B. Schmittmann and R. Zia, Coarsening dynamics of a quasi one-dimensional driven lattice gas, Europhysics Lett. 58, 653 (2002)
S. J. Cornell and A. J. Bray, Domain growth in a one-dimensional driven diffusive system, Phys. Rev. E 54, 1153 (1996).
D. L. Gonzalez, G. Tellez, Statistical behavior of domain systems, Phys. Rev. E 76, 011126 (2007).
D. L. Gonzalez and G. Tellez, Wigner surmise for domain systems, J. Stat. Phys. 132, 187 (2008).

A11 - A. Toom, UFPE, Brazil
Title: Substitution Operators: Rigorous Definitions
Abstract: We take a non-empty finite set A and call it alphabet. Elements of A are called letters. Our confuguration space S is the set of bi-infinite sequences of letters. M is the set of translation-invariant normalized measures on S, that is on the sigma-algebra generated by its cylinder subsets. Given two appropriate words U and V and a real number P in [0,1], we want to define an operator (which, generally speaking, has to be non-linear) from M to M, which, informally speaking, substitutes any entrance of the word U in any configuration by the word V with a probability P independently from what happens at other places. We have developed a rigorous definition of this operator and studies some of its properties. Our definition is based on approximation of measures by random words. A random word is a probability distribution on the set of words, in fact concentrated on a finite set of words. For any word W and any random word RW we define frequency of W in RW in a natural way. A random word RW is said to (L, epsilon) approximate a measure mu if for any word W, whose length does not exceed L, the difference of its frequencies in RW and in mu does not exceed epsilon. A sequence of random words is said to converge to a measure mu if its terms approximate it with L tending to infinity and epsilon tending to zero. First we define how our operator acts on random words and then, going to the limit, we define how it acts on measures. Theis work was done in collaboration with Andrea Vanessa Rocha and Alexandre Bustamante Simas.

A12 - W.K. Theumann, Univ. Fed. Rio Grande do Sul, Brazil
Title: Synchronous dynamics of recurrent neural networks with generalized Hebbian rule.
Coauthors: F.L. Metz
Abstract: The presence of frozen-in states in a recurrent neural network model of binary units with a synchronous dynamics and a Hebbian learning rule with a self-interaction has been known over some time and recent work (F. L. Metz and W. K. Theumann, J. Phys. A:Math. Theor. 41 (2008) 265001) using the generating functional approach for disordered systems shows that those states are unstable either to synaptic or to stochastic noise. That work is extended here for a symmetric generalized Hebbian rule that includes the learning of sequences of patterns. We show that frozen-in steady states and cycles of period two appear for a sufficiently large positive (excitatory) or negative (inhibitory) self-interaction, respectively, as well as a variety of other states that emerge from the dynamics in the absence of noise and we study the stability and the robustness of those states to noise.

A13 - B. Miller, Texas Christian University
Title: Synchronization and Stability in Two Neural Network Topologies
Coauthors: Tess Bernard and Scott Hill
Abstract: By adjusting only a few parameters, the Izhikevich model of the neuron can simulate all the known types of cortical neuron firing patterns. It was employed to investigate two network topologies: In the first, all elements are connected with randomly selected weights. The second consists of a small world network. In each case both excitation and inhibition are included. The dependence on key parameters of network stability and the onset of synchronization was investigated. The relevance of the results to real world phenomena, such as seizures, was considered.

A14 - D. Minh, National Institute of Health
Title: Free energy surfaces from bidirectional single-molecule force spectroscopy: asymptotic error and application to RNA constructs
Coauthors: John D. Chodera
Abstract: We demonstrate that a path-ensemble estimator recently developed by Minh and Adib (PRL 100, 180602 (2008)) is a nonequilibrium version of the multistate Bennett Acceptance Ratio, developed by Shirts and Chodera (JCP 129, 124105 (2008)), applied to bidirectional driven processes. This derivation leads to an expression for the asymptotic error. Using data from Collin et. al. (Nature 437, 231-234 (2005)), we apply the method to study the free energy surfaces of RNA constructs.

A15 - C. Zachary, Princeton University
Title: Determinantal point processes in high Euclidean dimensions
Coauthors: A. Scardicchio and S. Torquato
Abstract: It is well known that one can map certain properties of random matrices, fermionic gases, and zeros of the Riemann zeta function to a unique point process on the real line. We discuss exact generalizations of this point process to d-dimensional Euclidean space for any d, which are special cases of determinantal point processes. The n-particle correlation functions for any n can be written analytically, thereby completely specifying the point processes. These processes are characterized by an effective "hard-core" diameter that grows like the square root of d, and the nearest-neighbor distribution functions can be evaluated and rigorously bounded. This analysis reveals that the probability of finding a large spherical cavity of radius r in dimension d behaves like a Poisson point process but in dimension d+1. As d increases, the point process behaves effectively like a sphere packing with a coverage fraction of space no denser than 1/2^d. Statistical properties of the processes can numerically be studied via an algorithm capable of generating configurations of points in any dimension d.

A16 - M. Bishop, Manhattan College
Title: The shapes of two dimensional excluded volume continuum star polymers
Coauthors: C.von Ferber and J.Yates Moneith
Abstract: We have used renormalization group and Pivot Monte Carlo simulations to explore the shape of two dimensional tangent hard disk star polymers. The g-ratio and asphericity are examined and good agreement is found with previous studies with other polymer models.

A17 - P. Whitlock, Brooklyn College/CUNY
Title: Explorations of hard hyperspherical systems at higher densities
Coauthors: Marvin Bishop
Abstract: Using a compression methodology, we prepare hard hypersphere initial states at higher densities to be used in large scale Monte Carlo simulations. The pair correlation and structure functions of these systems reveal the onset of packing.

A18 - V. Shneidman, NJIT
Title: Time-dependent solution of the Becker-Doring equation for a short nucleation pulse
Abstract: Asymptotic analysis of the nucleation-growth equations describing a nucleation pulse of arbitrary duration is performed. After extended growth following the stage of intense nucleation, an asymptotic distribution of nuclei over sizes is established, which is not of any standard form (Gauss, log-normal, etc.) Regardless of the mass exchange mechanism between the nucleus and the the metastable phase, in the extremes of long and short pulses the shapes of the distribution become universal, with an additional insensitivity of either the maximum or, respectively, the width to the duration of the pulse.

A19 - G. Lee-Dadswell, Cape Breton University
Title: A momentum conserving one-dimensional system with a finite thermal conductivity
Coauthors: E. Turner, M. Moy, and J. Ettinger
Abstract: The question of what the criteria are for a system to have a finite thermal conductivity is currently unresolved. Much attention has been paid to one-dimensional (1D) systems. This is because, while "most" 1D systems have infinite thermal conductivities, there are a few known exceptions. The dominant view expressed in the literature at the moment is that momentum conservation is the key requirement for a system to have an infinite thermal conductivity. Systems with finite conductivities such as the "ding-a-ling" system, first described by Casatti, Ford, Vivaldi and Vischer, generally have on site potentials and do not conserve momentum as a result. We have investigated a modified version of the ding-a-ling system. By coupling the bound particles to each other instead of coupling them to lattice points we construct an analogue to the ding-a-ling system which conserves momentum. We call this the "momentum conserving ding-a-ling" (MCDL). This system is an interesting test case for current ideas about the mechanisms that lead to finite vs. infinite thermal conductivities. This system turns out to have a finite thermal conductivity, contrary to the prevailing view.

A20 - A. Baule, Rockefeller University
Title: Singular features of nonequilibrium steady state work fluctuations for Poisson noise
Coauthors: E. G. D. Cohen
Abstract: We study the work fluctuations of a particle, confined to a moving harmonic potential, under the influence of friction and external Poissonian shot noise. The asymmetry of the noise in this model induces an effective nonlinearity in the potential, which leads to singular features in the work distribution. We find in particular that the magnitudes of large negative and corresponding positive work fluctuations are comparable, though the average work is always positive, in agreement with the second law.

A21 - C. Van Vliet, University of Miami
Title: Modified Convergent (Linear) Response Theory
Abstract: Linear response theory is only useful if a posteriori a randomness assumption is made. Without this, it is a 'hollow shell' (van KAMPEN). Whereas previously we applied the interaction picture to the von Neumann equation (following Van Hove, Zwanzig and others), more applicable results are obtained if the Heisenberg equation is modified. On the one-particle Hartree-Fock level this leads directly to a very useful 'generalized Calecki equation' for the current flux, applicable to quantum transport involving extended or localised states (such as Landau orbits). We will draw attention to our recently published book "Equilibrium and Non-equilibrium Statistical Mechanics" (June 08) by WSPC, 960 pages. Part E gives the original Kubo-Green theory, as well as our modified response theory, pp. 679-877, with many condensed matter applications.

A22 - M. Kiessling, Rutgers University
Title: On Ruelle's construction of the thermodynamic limit for the classical microcanoncial entropy
Abstract: I show that Ruelle's 1969 construction of the thermodynamic limit for the classical microcanoncial entropy as defined with the usual regularized microcanonical measure also yields the same result for the properly defined entropy. Still, Ruelle's proof is based on regularization. I then show that the regularization is actually not needed at all.

A23 - W. Wreszinski, University of Sao Paulo
Title: A precise version of the third law
Coauthors: Elcio Abdalla

A24 - M. Widom, Carnegie Mellon University
Title: A van der Waals Loop in Supercooled Liquid Silicon
Coauthors: P. Ganesh
Abstract: First-principles molecular dynamics simulations of supercooled liquid silicon find a van der Waals loop in P(V) isotherms. The coexisting liquid states are a high-density liquid similar in properties to the high temperature equilibrium liquid, and a low-density liquid similar in some properties to the low temperature tetra-coordinated crystal structure. Our findings lend strong support to earlier predictions that were based on empirical interatomic interactions

A25 - K. Koga, Okayama University
Title: An infinite-order wetting transition
Coauthors: B. Widom, J. O. Indekeu
Abstract: The first-order and second-order wetting transition at fluid interfaces have been studied with several versions of mean-field density-functional models. Here we show one of such models may exhibit an infinite-order wetting transition.

A26 - A. Theumann, Univ. Fed. do Rio Grande do Sul, Brazil
Title: Quantum spherical spin-glass with long-range disorder
Coauthors: Pedro C. Menezes
Abstract: We present results of renormalization group calculations for the quantum spherical spin glass with correlated disorder decaying as 1/r^(d+\sigma) . We show that the effective partition function for the spin glass fluctuating fields separates into a mean field contribution analyzed before [P.C. Menezes and A. Theumann; Phys. Rev. B. 75 (2007) 024433] and a limited range contribution, that describes a phase transition in a field theory where the fluctuating fields depend on a space variable and two time variables. This we analyze by using the renormalization group with dimensional regularization and minimal subtraction of dimensional poles to order one loop [P.C. Menezes and A. Theumann; Phys. Rev. B. 78 (2008)054444 ].

A27 - M. Shlesinger, Office of Naval Research
Title: Defect Diffusion Model of the Glass Transition
Coauthors: J. Bendler and J. Fontanella

Session B

B1 - S. Ji, Rutgers University
Title: Modeling single-molecule enzyme kinetics based on Planck.s radiation formula and the principle of enthalpy-entropy compensation
Coauthors: Vishal Amin
Abstract: The prosthetic group of cholesterol oxidase (COx), FAD, is fluorescent when oxidized and non-fluorescent when reduced, making it possible to monitor the oxidation-reduction catalytic cycle of a single molecule of COx fluorometrically. H. Lu et al [Science 282:1877-1882 (1998)] report that the on-times, the times that COx wait before being reduced, are distributed asymmetrically over a wide range from 10 to 2,300 ms, depending on the concentration of cholesterol....See attached file for full abstract

B2 - S. Goradia, Gravity Research Institute, Inc
Title: Do Natural Units Probe Nature Better?
Abstract: Planck scale provides natural units. We show that interesting results can be obtained by replacing man-made units with these natural units. We modify and modernize the inverse square law of gravitation using these natural units. We extend probabilistic aspect of quantum physics to Newtonian gravitation and meet Einstein's view about strong coupling. See http://www.arXiv.org/pdf/physics/0210040v4. Emerging field of quantum computation replaces bits of information to qubits of information. We link time-unique qubits with statistical mechanics to explore if Einstein's implicit explanation of strong gravity can be further substantiated.

B3 - M. Kitsak, Boston University
Title: Leadership in Business Firm Networks
Abstract: We use the k-shell analysis to study the leadership of firms in the industry networks. We also address the long-standing question of how long does a typical leader in an industry maintain its position. We find that the Life Sciences industry network consists of three components: a "nucleus," which is a small well connected subgraph, "tendrils," which are small subgraphs consisting of small degree nodes connected exclusively to the nucleus, and a "bulk body" which consists of the majority of nodes. At the same time we do not observe the above structure in the Information and Communication Technology sector of industry. We also notice the remarkable stability of the nucleus of Life Sciences sector which is indicative of stability of industry leaders in this sector. At the same time, the absence of nucleus in the Information and Communication Technology sector may be explained by a high level of instability and turnover in the sector.

B4 - T. Ohira, University of Tokyo
Title: Temporal non-locality and Stochastic Time
Abstract: The equivalence or non-equivalence of space and time is one of the most fundamental issues in physics. There have been many intellectual endeavors with the theory of relativity at their center. This issue is expected to continue to attract numerous intellectuals from various academic disciplines.
We attempt to present a very modest approach to this topic by presenting a viewpoint for observing the concepts of ''stochasticity'' and ''non-locality'' on the time axis. Naturally, these are concepts we are familiar with in ''space'', but not in time. However, we can obtain rather complex dynamical behaviors by going back and forth between space and time axes around stochasticity and non-locality. We can present these by using a phenomenon called ''Stochastic Resonance'' Considering this phenomenon through the point of view of non-locality and stochasticity on both space and time axes provides a variety of resonance-like behaviors, many of which have yet to be mathematically understood.

B5 - J.C. Wleklinski, UIUC
Title: An Analytical Method for Solving the Boltzmann Equation

B6 - R. Fisch, Princeton University
Title: Critical behavior of randomly pinned spin-density waves
Abstract: A heat bath Monte Carlo method was used to obtain data for the Harris-Plischke-Zuckermann model with two-component (XY) classical spins on simple cubic lattices. The model was studied for D/J values of 2, 4, 6, 12 and infinity, on lattices up to size L= 64, using a 12-state discretization of the spins. For all values of D/J, the data indicate a well-defined critical temperature at which the longitudinal magnetic susceptibility diverges and the specific heat has a cusp. For each value of D/J we find critical exponents which are consistent with the usual scaling relations, as demonstrated using finite-size scaling. These exponents vary with D/J, however. Our results for the correlation length exponent \nu increase monotonically with D/J, with most of the variation taking place between D/J= 4 and 12. The exponent \eta, obtained from the structure factor for L= 64 lattices, is close to 0.10 for all D/J from 2 to 12. Its value for D/J= infinity is found to be about 0.02, consistent with earlier work.

B7 - S. Ulrich, University of Goettingen
Title: Cooling and aggregation in wet granulates
Coauthors: Stephan Ulrich*, Timo Aspelmeier, Klaus Roeller, Axel Fingerle, Stephan Herminghaus, Annette Zippelius
Abstract: Wet granular materials are characterized by bonds (liquid bridges) between particles, whereby breaking a bond implies an irreversible loss of a fixed amount of energy. Associated with the bond energy is a nonequilibrium transition, setting in as the granular temperature falls below the bond energy. The subsequent aggregation of particles into clusters is shown to be a self-similar growth process with a cluster size distribution that obeys scaling. In the early phase of aggregation the clusters are fractals, for later times we observe gelation. We use simple scaling arguments to derive the temperature decay in the early and late stages of cooling and verify our results with event-driven simulations.

B8 - H-C. Kaiser, Weierstrass Institute for Applied Analysis and Stochastics , Berlin
Coauthors: H. Gajewski, J. A. Griepentrog, and J. Rehberg
Title: A Thermodynamic Approach to Transient Kohn-Sham Theory
Abstract: The drift-diffusion Kohn-Sham theory provides a thermodynamically motivated model for charge transport in heterogeneous semiconductor materials with non-local operators for the charge carrier densities. The mobilities are chosen in accordance with the theory of large deviations in stochastic processes. The theory is in the general framework of Transient Density Functional Theory. but fundamentally differs from TD-DFT.

B9 - T. Platini, Virginia Tech (Post-doc. fellow)
Title: Stationary state of an open hard core bosonic chain
Coauthors: D. Karevski, R. M. Harris and S. Attal
Abstract: The local particles density of an open bosonic quantum chain in a stationary state has been studied. We introduce a dynamical disorder by the activation of a temporary coupling which is understood as the occurance of a fluctuation associated to the barrier of lattice. In this model, the interactions between the system and the environment are described by the repeated interaction process introduced by S. Attal. We consider a finite system (of size $L$) in interaction, on both ends, with two baths at different temperatures. Defining the probability distribution associated to the lattice fluctuations, we derive analytically the local density as a function of the different parameters of the model.

B10 - H. Raz, UC Davis
Title: Lieb Robinson Bounds in the Quantum Anharmonic Lattice
Coauthors: Bruno Nachtergaele, *Hillel Raz, Benjamin Schlein, Robert Sims
Abstract: We study locality bounds in lattice systems defined on infinite dimensional Hilbert spaces and described by unbounded Hamiltonians. We prove a Lieb-Robinson type bound for the harmonic lattice and for an anharmonic perturbation of it.

B11 - M. Stenlund, Courant Institute
Title: Memory loss in time-dependent dynamical systems
Coauthors: William Ott and Lai-Sang Young
Abstract: We discuss the evolution of probability distributions for certain time-dependent dynamical systems. We explain how expanding maps and one-dimensional piecewise expanding maps with slowly varying parameters lose memory exponentially. What is new is that the stationarity of the process is entirely irrelevant. Neither do the constituent maps have to belong to a bounded family, in which case the rates of memory loss may vary over time.

B12 - N. Khatiashvili, Vekua Institute of Applied Mathematics
Title: On the 2D Quantum Billiard Problem
Abstract: The Classical Quantum Billiard for the simply connected region in the plane is considered. This model is described by the Helmholtz Equation with the homogeneous boundary condition.By the conformal mapping and integral equation method the efficient formulaes for the calculation of the eigenvalues of this problem are derived. Thus, the energetic levels of the particle could be found. The result is applied to the particular cases (hexagon and Lemniscat).

B13 - M. Tierz, Brandeis University
Title: Random matrices in Chern-Simons theory
Abstract: I briefly present a random matrix description of non-Abelian Chern-Simons theory. So far, it has been employed in topological string theory but I will show that the random matrices and 1D exactly solvable models involved are also intimately related to Laughlin wavefunctions on the cylinder and to a 1D charged Bose gas.

B14 - L.J. Cook, Virgina Tech.
Title: Competition For Resources in a Model for Protein Synthesis
Coauthors: R. K. P. Zia
Abstract: The Totally Asymmetric Simple Exclusion Process (TASEP) is often used to explore translation during protein synthesis. The particles represent ribosomes that move along mRNA, which is represented by the one-dimensional lattice. Unlike ordinary TASEP where the supply of particles is unlimited, there is a finite number of ribosome in a cell. In addition, there are many genes which compete for this pool of ribosomes. Thus, we are motivated to consider the effects of multiple TASEPs (of varying lengths) coupled to a single, finite reservoir of particles. In particular, the total occupation numbers, the density profiles and the particle currents of individual TASEPs are studied, as the overall reservoir of particles is varied. Both Monte Carlo simulation results and analytic considerations will be presented.

B15 - N. Araujo, Universidad do Minho, Portugal
Title: Kinetics of random sequential adsorption on patterned substrates
Coauthors: A. Cadilhe and V. Privman
Abstract: Kinetics of irreversible adsorption on patterned substrates is studied through extensive Monte Carlo simulations. As a pattern, equal size cells, with square shape, are considered. Adsorption can only take place when landing particles fall inside the cells without overlapping previously adsorbed ones (hard-core interaction). Ranging the values of the cell size and the distance between cells a transition from power-law to exponential is observed in the coverage approach to the jammed state limit.

B16 -Y-L. Chou, Virginia Tech
Title: Deposition model with temperature dependent diffusion
Coauthors: Michel Pleimling
Abstract: We study a deposition process where the deposed particles are allowed to hope to their neighboring sites with a probability that depends both on the temperature and on the height difference. Changing the temperature, the model evolves from the random deposition model with surface relaxation at zero temperature to the random deposition model at infinite temperature. A generalized dynamic scaling of the surface width as a function of the lattice size, the deposition time, and the temperature is given. An appealing feature of this model is the possibility to study the response to a sudden change in temperature.

B17 - M. Filoche, Ecole Polytechnique
Title: Diffusion Reorganized Agregates
Coauthors: Bernard Sapoval
Abstract: We present a restructuration model in which particles leave the surface of a structure, diffuse in the surrounding bulk then are redeposited in another location at the surface of the same structure. The initial structure then naturally evolve towards a quasi-equilibrium branched geometry, with fractal behavior. The equilibrium, dynamic and ergodic properties of this model will be discussed.

B18 - S. Dorosz, Virginia Tech.
Title: Non reversible dynamics and the detailed fluctuation theorem
Coauthors: Michel Pleimling
Abstract: We consider reaction-diffusion models driven out of the stationary state in a finite time as one of the reaction rates is changed. In cases where microscopic time reversibility is broken, we find systematic deviations to the detailed fluctuation theorem. We discuss the dependence of this phenomenon on the different system parameters and explain our observation through the connectivity in configuration space.

B19 - A. Cadilhe, Los Alamos National Laboratory
Title: Quantifying departure from equilibrium in driven systems
Coauthors: A. F. Voter
Abstract: A generalized force acting on a system pulls it away from its equilibrium. A natural question arises concerning how far the system has departed from equilibrium. We address this issue for a particle immersed in a time-dependent parabolic well and in contact with a heat reservoir by changing the driving rate.

B20 - Y. Dubi, University of California, San Diego
Title: Fourier's law reconstructed from disorder in electronic quantum wires
Coauthors: M. Di Ventra
Abstract: We present a novel theory of open quantum systems, by which one can study the local temperature and heat current in metallic nanowires connected to leads at different temperatures. We show that for ballistic wires the local temperature is almost uniform along the wire and Fourier's law is invalid. By gradually increasing disorder, a uniform temperature gradient ensues inside the wire and the thermal current linearly relates to this local temperature gradient, in agreement with Fourier's law. Finally, we demonstrate that while disorder is responsible for the onset of Fourier's law, the non-equilibrium energy distribution function is determined solely by the heat baths.

B21 - M. Olshanii, University of Massachusetts
Title: Thermalization and its mechanism for generic isolated quantum systems
Coauthors: Marcos Rigol, Vanja Dunjko
Abstract: We perform an ab initio numerical analysis of a system of hard-core bosons on a lattice [1], in order to confirm the Eigenstate Thermalization Hypothesis formulated by Deutsch [2] and Srednicki [3]. According to this hypothesis, in quantum systems thermalization happens at the level of individual eigenstates, but hidden initially by coherences between them. In course of time evolution the thermal properties become revealed through (linear) decoherence. Unlike in the classical case, in quantum evolution linear dynamics is sufficient to ensure thermalization.

B22 - E. Akkermans, Yale and Technion
Title: Photon localization and Dicke superradiance : a small world network
Coauthors: Aharon Gero Robin Kaiser
Abstract: Photon propagation in a gas of N atoms is studied using an effective Hamiltonian describing photon mediated atomic dipolar interactions. The density of photon escape rates is determined from the spectrum of a new kind of Euclidean random matrix. Varying disorder and system size, a scaling behavior is observed for the escape rates. It is explained using a stochastic model which emphasizes the role of cooperative effects in photon localization and provides an interesting relation with statistical properties of "small world networks."

B23 - R. Batten, Princeton University
Title: Collective Coordinates and Classical Disordered Ground States
Coauthors: F. H. Stillinger and S. Torquato
Abstract: Classical disordered ground states (energy minimizing many-particle configurations) are constructed in one, two, and three dimensions by imposing constraints on the collective coordinates of a system of particles. These are ground states for a class of long-ranged and oscillatory pair potential functions and exhibit anomalous macroscopic behavior.

B24 - L. Bertini, Univ. La Sapienza
Title: On the shape of a droplet above a wall
Coauthors: P. Butta' and A. Garroni
Abstract: We consider the Van der Waals functional on a half plane with a boundary condition imposing a droplet of linear size L and no volume constraint. We compute the asymptotic shape of the droplet as L diverges.

B25 - N. Giovambattista, Brooklyn College of the University of New York
Title: Phase transitions induced by nano-confinement in liquid water Coauthors: P. J. Rossky and P. G. Debenedetti
Abstract: We present results from molecular dynamics simulations of water confined by two parallel atomically-detailed hydrophobic walls. Simulations are performed at T = 300 K and wall-wall separation 0.6 <= d <= 1.6 nm. At d=0.7-0.9 nm, a first order transition occurs between a bi- layer liquid (BL) and a trilayer heterogeneous fluid (THF) as water density increases. The THF is characterized by a liquid (central) layer and two crystal-like layers next to the walls. The BL-THF transition involves an order-disorder transformation in water structure (similar to melting) next to the walls. At d = 0.6 nm, the THF transforms into a bilayer ice (BI). Both the BL-THF and BI-THF transitions are induced by the surface atomic-level structure. Thus, the observed nanoconfined water structures are qualitatively different from those found in bulk water.

B26 - M. Hincewzski, Technical University of Munich
Title: End-monomer dynamics of semiflexible polymers
Coauthors: Xaver Schlagberger, Michael Rubinstein, Oleg Krichevsky, Roland R. Netz
Abstract: Spurred by a controversy in recent studies of single DNA molecules with a fluorescently labeled end, we investigate the end-monomer dynamics of semiflexible polymers through Brownian hydrodynamic simulations and a dynamic mean-field theory. Both theory and simulation point to a novel intermediate dynamical regime for fluctuations at length scales larger than the persistence length, deviating from the classic Zimm prediction for polymer behavior in solution.

B27 - A. Kabakcioglu, Koc University
Title: Supercoil formation in DNA denaturation
Coauthors: Enzo Orlandini and David Mukamel
Abstract: We generalize the Poland-Scheraga (PS) model to the case of a circular DNA, taking into account the twisting of the two strains around each other. Guided by recent single-molecule experiments on DNA strands, we assume that the torsional stress induced by denaturation enforces formation of supercoils whose writhe absorbs the linking number expelled by the loops. We ﬁnd that when the the entropy parameter of a loop satisﬁes c ≤ 2, denaturation transition does not take place. On the other hand for c > 2 a ﬁrst-order denaturation transition takes place, as in the case with no supercoil. These results are in contrast with other treatments of circular DNA melting where denaturation is assumed to be accompanied by an increase in twist rather than writhe.

B28 - G. Papoian, UNC Chapel Hill
Title: Molecular Noise of Capping Protein Binding Induces Macroscopic Instability in Filopodial Dynamics
Coauthors: Pavel I. Zhuravlev
Abstract: Capping proteins are among the most important regulatory proteins involved in controlling complicated stochastic dynamics of ﬁlopodial growth. They attach to the barbed end of a ﬁlament and prevent polymerization, leading to eﬀective ﬁlament retraction due to retrograde ﬂow. When we have simulated ﬁlopodial growth in presence of capping proteins, qualitatively new dynamics emerged. We discovered that molecular noise due to capping protein binding and unbinding leads to macroscopic ﬁlopodial length ﬂuctuations, compared with minuscule ﬂuctuations in the actin only system. When capped, some ﬁlaments eventually retract all the way down to ﬁlopodial base and disappear. This process endows ﬁlopodium with a ﬁnite lifetime.

B29 - B. Sauerwine, Carnegie Mellon University
Title: Folding Kinetics of Riboswitch Transcriptional Terminators
Coauthors: Michael Widom
Abstract: In this work we study the efficiency in folding pathways of transcriptional terminators of riboswitches in the Bacillus and Streptococcus family using the ViennaRNA package. These riboswitches act as primitive sensors and as such are responsible for the dissociation of RNA from the DNA-RNA complex based on the presence of a ligand in order to mediate expression of a gene.

B30 - G. Ramirez-Santiago, Instituto de Fisica, UNAM, Mexico
Title: Non-linear phenomena in the kinetics of phosphorilation-dephosphorilation reactions in the cell
Coauthors: Vladimir Gomez-Diaz
Abstract: Protein dynamics in the cell is intimately related to enzymatic catalysis. We have studied the kinetics of the phosphorilation-dephosphorilation reaction network. We find nonlinear phenomena such as bifurcatios and hysteresis in the behavior of the concentrations of the products.

B31 - O. Guzman, UAM-Iztapalapa
Title: Hydrodynamics and optical textures in liquid-crystal based biosensors
Coauthors: David Castañeda, David Cruz, José A. Vélez
Abstract: Experimental biosensors based on liquid crystals (LC) use thin films of nematics to detect the presence of specific biomolecules, via the optical textures exhibited by the LC at long times. Efforts to model the time evolution of these textures have relied on relaxational models, ignoring transport phenomena. With a lattice Boltzmann method, we study the impact of hydrodynamic effects on the lifetime of multidomain structures, which are observed at high concentrations of analyte, and the interaction of topological defects present in the sensor. In addition, we explore the response of the liquid crystal to confinement by spatially modulated anchoring, on length scales comparable to that of visible light.

B32 - C. Thomas, Syracuse University
Title: Patchwork Dynamics for Glassy Models
Coauthors: A. Middleton
Abstract: Glassy dynamics in disordered materials prohibits the direct simulation of their nonequilibrium behavior at large scales. We present patchwork dynamics, a technique in which local Monte Carlo updates are replaced by exact equilibration on patches at a given length scale. In cases where fast equilibration or ground state algorithms exist, this technique can immensely speed up simulations.

B33 - H. Katzgraber, ETH Zurich
Title: Spin glasses: A one-dimensional view
Coauthors: A. Peter Young and A. K. Hartmann
Abstract: Results of a one-dimensional long-range Ising spin-glass model with power-law (diluted) interactions are presented, where one can tune effectively the space dimension by changing the power-law exponent.

B34 - A. Middleton, Syracuse University
Title: Patching together dynamics for disordered spin models
Coauthors: Creighton Thomas
Abstract: The equilibration of glassy models is difficult to study numerically due to the very slow dynamics of these models. We propose using direct equilibration at a sequence of length scales, imposed using exact algorithms, to study the time evolution of disordered models such as spin glasses. This simple approach reproduces memory effects seen in spin glasses and also allows one to find ground states for boundary conditions that are otherwise difficult to solve.

B35 - T. Prellberg, Queen Mary, University of London
Title: A self-interacting partially directed walk subject to a force
Coauthors: R. Brak (Melbourne), P. Dyke (Toronto), J. Lee (Toronto), A. L. Owczarek (Melbourne), A. Rechnitzer (Vancouver), and S. G. Whittington (Toronto)
Abstract: We consider a directed walk model of a homopolymer (in two dimensions) which is self-interacting and can undergo a collapse transition, subject to an applied tensile force. We review and interpret all the results already in the literature concerning the case where this force is in the preferred direction of the walk. We consider the force extension curves at different temperatures as well as the critical-force temperature curve. We demonstrate that this model can be analysed rigorously for all key quantities of interest even when there may not be explicit expressions for these quantities available. We show which of the techniques available can be extended to the full model, where the force has components in the preferred direction and the direction perpendicular to this. Whilst the solution of the generating function is available, its analysis is far more complicated and not all the rigorous techniques are available. However, many results can be extracted including the location of the critical point which gives the general critical-force temperature curve. Lastly we generalise the model to a three-dimensional analogue and show that several key properties can be analysed if the force is restricted to the plane of preferred directions.

Session C

C1 - S. Hill, University of Dallas
Title: A model for dynamic centrality in scale-free networks
Abstract: A recent paper (Braha and Bar-Yam, Complexity 12(2):59-66 (2006)) considered the daily email networks in a large corporation, and discovered the existence of dynamic centrality: each daily network was scale-free (as was the overall email network), but the large-degree "hubs" changed from day to day. In this talk we introduce an algorithm for creating a series of subnetworks on top of a large scale-free network. With the introduction of preferential attachment, we show that these subnetworks possess hubs which vary from day to day and are somewhat independent of the hubs of the underlying network, thereby demonstrating dynamic centrality as seen in the experiment.

C2 - D. Han, Jiao Tong University, P.R. China
Title: The Effect of Spread of Epidemics on Shaping Network Topology
Coauthors: N/A
Abstract: We shall talk about how the spread of epidemics on a growing network affect on shaping the network topology. It is shown that the connectivity distribution will not be scale-free if one adds a link only to the healthy nodes.

C3 - J. Simmons, Oxford University
Title: A new SLE result for kappa = 8/3
Coauthors: J. Cardy
Abstract: A self-avoiding walk starting at the origin and traversing the half-plane can be described, in the continuum limit, by an SLE_{8/3} process. We present a conformal field theoretic result extending Schramm's left-crossing probability for this system to probabilities of winding about two marked points in the plane.

C4 - A. Kemppainen, University of Helsinki
Title: Scaling limit for 2D random curves Coauthor: Stanislav Smirnov Abstract: Random curves arise as interfaces in 2-dimensional models of statistical mechanics. At criticality these models are expected to be conformally invariant. Schramm-Loewner evolution (SLE) or its variants are in this case the only possible candidates for the scaling limit. Proving the convergence of a random curve to SLE can be done in two parts. First establish a priori bounds: compactness of the sequence of the probability measures and that the subsequential limits of the sequence are nice enough so that we can use Loewner equation to describe them. Second part is to prove that the subsequential limit is infact unique and hence the whole sequence converges. In this talk I will concentrate on the first part which we consider as an extension of work of M.Aizenman and A.Burchard (1999). It turns out that all the a priori bounds are implied by a simple bound.

C5 - M. Balazs, Budapest University of Technology and Economics
Title: t1/3-order current fluctuations in interacting particle systems
Coauthors: Julia Komjathy and Timo Seppalainen
Abstract: The behavior of one dimensional interacting particle systems with one conserved quantity is described by a conservation law in the Eulerian hydrodynamic limit. In natural cases the hydrodynamic flux is concave (sometimes convex). A corresponding microscopic concavity (convexity) property in the level of the particle system allows us to prove that time-integrated current fluctuations along the characteristics scale with 1/3-rd power of time, as predicted by the KPZ picture where these models belong to.

C6 - I. Papageorgiou, Imperial College
Title: The Log-Sobolev inequality for unbounded spin systems on the Lattice
Coauthors: N/A
Abstract: We are interested in the Log Sobolev inequality for unbounded spin systems on the Lattice. We focus on local specifications with interactions that go beyond the usual strict convexity.
In this talk, conditions are determined under which the infinite dimensional Gibbs measure of such local specifications satisfies the Log-Sobolev inequality.
More detailed, at first a criterion is presented, for local specifications that satisfy the Log-Sobolev inequality on single site sets uniformly on the boundary conditions. Then the criterion is extended to such specifications that the LS inequality is true for the one dimensional boundary-free measure.

C7 - A. Nachmias, Microsoft Research
Title: The Alexander and Orbach conjecture holds in high dimensions
Coauthors: Gady Kozma
Abstract: It is known that the simple random walk on the unique infinite cluster of supercritical percolation on Z^d diffuses in the same way it does on the original lattice. In critical percolation, however, the behavior of the random walk changes drastically.
The infinite incipient cluster (IIC) of percolation on Z^d can be thought of as the critical percolation cluster conditioned on being infinite. Alexander and Orbach (1982) conjectured that the spectral dimension of the IIC is 4/3. This means that the probability of an n-step random walk to return to its starting point scales like n^{-2/3} (in particular, the walk is recurrent). In this work we prove this conjecture when d>18; that is, where the lace-expansion estimates hold.
Joint work with Gady Kozma.

C8 - A. Gabrielli, CNR-INFM, Rome
Title: Two-point correlation properties of stochastic cloud processes
Coauthors: M. Joyce
Abstract: We study how the two-point density correlation properties of a point particle distribution are modified when each particle is divided, by a stochastic process, into an equal number of identical "daughter" particles. We consider generically that there may be non-trivial correlations in the displacement fields describing the positions of the different daughters of the same "mother" particle, and then treat separately the cases in which there are, or are not, correlations also between the displacements of daughters belonging to different mothers. For both cases exact formulae are derived relating the structure factor (power spectrum) of the daughter distribution to that of the mother. These results can be considered as a generalization of the analogous equations obtained in ref. [1] (cond-mat/0409594) for the case of stochastic displacement fields applied to particle distributions. An application of the present results is that they give explicit algorithms for generating, starting from regular lattice arrays, stochastic particle distributions with an arbitrarily high degree of large-scale uniformity.

C9 - J.C.A. Armas-Perez, UNAM -
Title: Mesophases of the p-q model in 2 dimensions
Coauthors: J. Quintana
Abstract: We propose a new bidimensional model, called p-q, with chiral and anisotropic characteristics and infinitely repulsive interactions. Our model presents well known limiting cases such as hard rods and hard disks. We studied several molecular shapes and for some of them we found numerical evidence for liquid crystalline phases. We use Monte Carlo simulations in particular isobaric and Gibbs ensembles.

C10 - Y. Liu, University of Illinois at Urbana-Champaign
Title: Random-field Ising model in and out of equilibrium
Coauthors: Karin A. Dahmen
Abstract: We present numerical studies of random-field Ising model at zero-termperature in both equilibrium and non-equilibrium. We compare the no-passing rule, mean-field exponents, and universal quantities in 3D (critical exponents, scaling functions, avalanche fractal dimensions and anisotropy measures) for the equilibrium and non-equilibrium disorder-induced phase atransitions. We show compelling evidence that the two transitions belong to the same universality class.

C11 - D. Talaga, Rutgers University
Title: Information theoretical approach to single molecule experimental design and interpretation
Coauthors: N/A
Abstract: Time correlated single photon counting allows luminescence lifetime information to be determined on a single molecule level. This paper develops a formalism to allow information theory analysis of the ability of luminescence lifetime measurements to resolve states in a single molecule. It analyzes the information content of the photon stream and the fraction of that information that is relevant to the state determination problem. Experimental losses of information due to instrument response, digitization, and different types of background are calculated and a procedure to determine the optimal value of experimental parameters is demonstrated. This paper shows how to use the information theoretical formalism to evaluate the number of photons required to distinguish dyes that differ only by lifetime. It extends this idea to include distinguishing molecular states that differ in the electron transfer quenching or resonant energy transfer and shows how the differences between the lifetime of signal and background can help distinguish the dye position in an excitation beam.

C12 - P. Hurtado, Universidad de Granada
Title: Confirmation of the Additivity Principle for Current Fluctuations in a Model of Heat Conduction
Coauthors: Pedro Garrido
Abstract: The additivity principle allows to compute the current distribution in many one-dimensional (1D) nonequilibrium systems. Using simulations, we confirm this principle in the 1D Kipnis-Marchioro-Presutti model of heat conduction. In this case the current distribution shows both Gaussian and non-Gaussian regimes, obeying in all cases the Gallavotti-Cohen fluctuation theorem. We verify the existence of a well-defined temperature profile associated to a given current fluctuation. This profile is independent of the current sign, and this symmetry extends to higher-order profiles and spatial correlations. We also show that finite-time joint fluctuations of the current and the temperature profile are described by the additivity functional. These results confirm the additivity hypothesis as a general and powerful tool to compute current distributions in many 1D nonequilibrium systems.

C13 - R. Harris, Queen Mary, University of London
Title: Current fluctuations in systems with memory-dependent rates
Abstract: We propose a method to calculate the large deviations of current fluctuations in a class of stochastic particle systems with history-dependent rates (leading to long-range memory effects). Some illuminating examples are given. [TBC]

C14 - A. Rakos, Hungarian Academy of Sciences
Title: Logarithmic current fluctuations in non-equilibrium quantum spin chains
Coauthors: P.L. Krapivsky and Tibor Antal
Abstract: We study zero-temperature quantum spin chains which are characterized by a non-vanishing current. For the XX model starting from the initial state |...+++---...> we derive an exact expression for the variance of the total spin current. We show that asymptotically the variance exhibits an anomalously slow logarithmic growth. We then argue that the logarithmic growth remains valid for the XXZ model in the critical region.

C15 - T. Reichenbach, Rockefeller University
Title: Mobility and pattern formation of cyclically competing populations
Coauthors: M. Mobilia and E. Frey
Abstract: Self-formation of noisy patterns governs species coevolution in spatially extended, biodiverse ecosystems. Individuals that organize into such patterns are often mobile: bacteria run and tumble, and animals migrate from place to place. We show that mobility has intriguing impact on form and size of the self-forming spatial structures, and thereby on the possibility of species diversity. Employing a specific model for cyclic (rock-paper-scissors-type) competition of species, we show that, under the influence of mobility, surprisingly regular, geometric patterns form. Namely, a noisy entanglement of rotating spiral waves self-organizes in the course of time. A critical value of mobility separates this biodiverse scenario from a uniform one where only one species survives.

[1] Tobias Reichenbach, Mauro Mobilia, Erwin Frey, Nature 448, 1046-1049 (2007) [2] Tobias Reichenbach, Mauro Mobilia, Erwin Frey, Phys. Rev. Lett. 101, 058102 (2008)

C16 - J. Wehr, University of Arizona
Title: Entanglement Percolation in Quantum Networks
Coauthors: John Lapeyre, Maciej Lewenstein
Abstract: We transmit quantum information using a lattice of qubit pairs. For faithful transmission, maximally entangled pairs have to be used. Following the idea of Acin et al. we show that on several two-dimensional lattices, preliminary quantum measurements, changing the geometry of the lattice, enhance the transmission probability. We use FKG inequality and numerical simulations of classical percolation models.

C17 - A. Ayyer, CEA, Saclay, France
Title: Lattice paths in the quarter plane: Some conjectures akin to Gessel's
Abstract: The enumeration of lattice paths are extremely useful in the analysis of the physics of polymers. We study the problem of enumeration of certain lattice paths constrained to lie in the first quadrant and state some new conjectures in this area.

C18 - P. Kleban, University of Maine
Title: Factorization of Cluster Density Correlations in Critical 2-D Percolation in Rectangles
Coauthors: J. J. H.Simmons, Oxford and R. M. Ziff, Michigan
Abstract: We show that certain higher-order cluster density correlation functions for critical 2-D percolation in rectangles with fixed b.c. on two opposite sides and open b.c. on the other two factorize almost exactly into lower-order correlation functions. Further, the deviation from factorization only depends on one co-ordinate. Both numerical results and exact formulas (from conformal field theory) are given.