
Abstract: We study how the loading rate, specimen geometry, and microstructural texture select the dynamics of a crack moving through an heterogeneous elastic material in the quasistatic approximation. We find a transition, fully controlled by two dimensionless variables, between dynamics ruled by continuum fracture mechanics and crackling dynamics. Selection of the latter by the loading, microstructure, and specimen parameters is formulated in terms of scaling laws on the power spectrum of crack velocity. This analysis defines the experimental conditions required to observe crackling in fracture. Beyond failure problems, the results extend to a variety of situations described by models of the same universality class, e.g., the dynamics in wetting or of domain walls in amorphous ferromagnets. 
BibTeX:
@article{Bares2013, author = {Barés, J. and Barbier, L. and Bonamy, D.}, title = {Crackling versus Continuumlike Dynamics in Brittle Failure}, journal = {Physical Review Letters}, year = {2013}, volume = {111}, number = {5}, pages = {054301}, doi = {10.1103/PhysRevLett.111.054301} } 
BibTeX:
@conference{Barlet2013a, author = {M. Barlet and J.M. Delaye and D. Bonamy and C. L. Rountree}, title = {“Understanding the evolution of mechanical properties under irradiation in nuclear glasses via experiments.”}, booktitle = {13th International Conference on Fracture}, year = {2013}, url = {http://www.gruppofrattura.it/ocs/index.php/ICF/icf13/paper/download/11521/10900} } 

Abstract: This paper is devoted to a comparison of experimental, simulation, and theoretical results on the density of SiO2B2O3Na2O glasses. It is found that theoretical and simulation densities do compare favorably with experimental values yet simulations give a better estimate of the density of the samples. Furthermore, the structural makeup (i.e. types of borate and silicate units) of the ternary glasses and the volume of the elementary units have also been investigated with simulations and compared to theory. These results are found to compare favorably when R < Rd1 (R = [Na2O]/[B2O3], K = [SiO2]/[B2O3] and Rd1 = 0.5 + 0.25K) yet variations do exists when R > Rd1. These variations include more Na+ ions attaching to the borate network in simulations than theorized. (C) 2013 Elsevier B.V. All rights reserved. 
BibTeX:
@article{Barlet2013, author = {Barlet, M. and Kerrache, A. and Delaye, J.M. and Rountree, C. L.}, title = {SiO2Na2OB2O3 density: A comparison of experiments, simulations, and theory}, journal = {Journal of Noncrystalline Solids}, year = {2013}, volume = {382}, pages = {3244}, doi = {10.1016/j.jnoncrysol.2013.09.022} } 

Abstract: The term active nematics designates systems in which apolar elongated particles spend energy to move randomly along their axis and interact by inelastic collisions in the presence of noise. Starting from a simple Vicsekstyle model for active nematics, we derive a mesoscopic theory, complete with effective multiplicative noise terms, using a combination of kinetic theory and Ito calculus approaches. The stochastic partial differential equations thus obtained are shown to recover the key terms argued in Ramaswamy et al (2003 Europhys. Lett. 62 196) to be at the origin of anomalous number fluctuations and longrange correlations. Their deterministic part is studied analytically, and is shown to give rise to the longwavelength instability at onset of nematic order (see Shi X and Ma Y 2010 arXiv:1011.5408). The corresponding nonlinear densitysegregated band solution is given in a closed form. 
BibTeX:
@article{Bertin2013, author = {Bertin, Eric and Chate, Hugues and Ginelli, Francesco and Mishra, Shradha and Peshkov, Anton and Ramaswamy, Sriram}, title = {Mesoscopic theory for fluctuating active nematics}, journal = {New Journal of Physics}, year = {2013}, volume = {15}, pages = {085032}, doi = {10.1088/13672630/15/8/085032} } 

Abstract: Thin soft elastic layers serving as joints between relatively rigid bodies may function as sealants, thermal, electrical, or mechanical insulators, bearings, or adhesives. When such a joint is stressed, even though perfect adhesion is maintained, the exposed free meniscus in the thin elastic layer becomes unstable, leading to the formation of spatially periodic digits of air that invade the elastic layer, reminiscent of viscous fingering in a thin fluid layer. However, the elastic instability is reversible and rateindependent, disappearing when the joint is unstressed. We use theory, experiments, and numerical simulations to show that the transition to the digital state is sudden (firstorder), the wavelength and amplitude of the fingers are proportional to the thickness of the elastic layer, and the required separation to trigger the instability is inversely proportional to the inplane dimension of the layer. Our study reveals the energetic origin of this instability and has implications for the strength of polymeric adhesives; it also suggests a method for patterning thin films reversibly with any arrangement of localized fingers in a digital elastic memory, which we confirm experimentally. 
BibTeX:
@article{Biggins2013, author = {Biggins, John S. and Saintyves, Baudouin and Wei, Zhiyan and Bouchaud, Elisabeth and Mahadevan, L.}, title = {Digital instability of a confined elastic meniscus}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, year = {2013}, volume = {110}, number = {31}, pages = {1254512548}, doi = {10.1073/pnas.1302269110} } 

Abstract: We present fluorescence recovery measurements after photobleaching performed under high pressure in liquids that fill squaresection fused silica microcapillaries. These microcapillaries withstand pressure up to 2500 bar for a wall thickness of about 140 mu m and fit easily on the microscope stage. This technique allows the translational diffusion coefficient of fluorescent molecules in liquids to be measured as a function of pressure. When the liquid sample is far from its glass transition the translational diffusive coefficient is in agreement with the StokesEinstein equation. As the glass transition is approached by further increasing the pressure, decoupling of the measured diffusion coefficient from the StokesEinstein relation is observed. These are the first measurements that combine the fluorescence recovery technique and high hydrostatic pressures. This experimental setup can also be used either with diamond or sapphire anvil cells in order to span a larger pressure range. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4790567] 
BibTeX:
@article{Bonetti2013, author = {Bonetti, Marco and Roger, Michel}, title = {Translational diffusion of probe molecules under high pressure: A study by fluorescence recovery after photobleaching technique}, journal = {Review of Scientific Instruments}, year = {2013}, volume = {84}, number = {2}, doi = {10.1063/1.4790567} } 

Abstract: We report quench cooling experiments performed with liquid O2 under different levels of gravity, simulated with magnetic gravity compensation. A copper disk is quenched from 300 to 90 K. It is found that the cooling time in microgravity is very long in comparison with any other gravity level. This phenomenon is explained by the insulating effect of the gas surrounding the disk. A weak gas pressurization (which results in subcooling of the liquid with respect to the saturation temperature) is shown to drastically improve the heat exchange, thus reducing the cooling time (about 20 times). The effect of subcooling on the heat transfer is analyzed at different gravity levels. It is shown that this type of experiment cannot be used for the analysis of the critical heat flux of the boiling crisis. The film boiling heat transfer and the minimum heat flux of boiling are analyzed as functions of gravity and subcooling. 
BibTeX:
@article{Chatain2013, author = {Chatain, D. and Mariette, C. and Nikolayev, V. S. and Beysens, D.}, title = {Quench cooling under reduced gravity}, journal = {Physical Review E}, year = {2013}, volume = {88}, number = {1}, pages = {013004}, doi = {10.1103/PhysRevE.88.013004} } 

Abstract: Linear elastic fracture mechanics provides a consistent framework to evaluate quantitatively the energy flux released to the tip of a growing crack. Still, the way in which the crack selects its velocity in response to this energy flux remains far from completely understood. To uncover the underlying mechanisms, we experimentally studied damage and dissipation processes that develop during the dynamic failure of polymethylmethacrylate, classically considered as the archetype of brittle amorphous materials. We evidenced a welldefined critical velocity along which failure switches from nominallybrittle to quasibrittle, where crack propagation goes hand in hand with the nucleation and growth of microcracks. Via postmortem analysis of the fracture surfaces, we were able to reconstruct the complete spatiotemporal microcracking dynamics with micrometer/nanosecond resolution. We demonstrated that the true local propagation speed of individual crack fronts is limited to a fairly low value, which can be much smaller than the apparent speed measured at the continuumlevel scale. By coalescing with the main front, microcracks boost the macroscale velocity through an acceleration factor of geometrical origin. We discuss the key role of damagerelated internal variables in the selection of macroscale fracture dynamics. 
BibTeX:
@article{Dalmas2013, author = {Dalmas, Davy and Guerra, Claudia and Scheibert, Julien and Bonamy, Daniel}, title = {Damage mechanisms in the dynamic fracture of nominally brittle polymers}, journal = {International Journal of Fracture}, year = {2013}, volume = {184}, number = {12}, pages = {93111}, doi = {10.1007/s107040139839y} } 

Abstract: Recent years have witnessed a growing interest in covariant Lyapunov vectors (CLVs) which span local intrinsic directions in the phase space of chaotic systems. Here, we review the basic results of ergodic theory, with a specific reference to the implications of Oseledets' theorem for the properties of the CLVs. We then present a detailed description of a 'dynamical' algorithm to compute the CLVs and show that it generically converges exponentially in time. We also discuss its numerical performance and compare it with other algorithms presented in the literature. We finally illustrate how CLVs can be used to quantify deviations from hyperbolicity with reference to a dissipative system (a chain of Henon maps) and a Hamiltonian model (a FermiPastaUlam chain). 
BibTeX:
@article{Ginelli2013, author = {Ginelli, Francesco and Chate, Hugues and Livi, Roberto and Politi, Antonio}, title = {Covariant Lyapunov vectors}, journal = {Journal of Physics Amathematical and Theoretical}, year = {2013}, volume = {46}, number = {25}, pages = {254005}, doi = {10.1088/17518113/46/25/254005} } 

Abstract: Like any fluid heated from below, the atmosphere is subject to vertical instability that triggers convection. Convection occurs on small time and space scales, which makes it a challenging feature to include in climate models. Usually subgrid parameterizations are required. Here, an alternative view based on a global thermodynamic variational principle is developed. Convective flux profiles and temperature profiles at steady state are computed in an implicit way by maximizing the associated entropy production rate. Two settings are examined, corresponding respectively to an idealized case of a gray atmosphere and a realistic case based on a net exchange formulation radiative scheme. In the second case, the effect of variations of the atmospheric composition, such as a doubling of the carbon dioxide concentration, is also discussed. 
BibTeX:
@article{Herbert2013, author = {Herbert, C. and Paillard, D. and Dubrulle, B.}, title = {Vertical Temperature Profiles at Maximum Entropy Production with a Net Exchange Radiative Formulation}, journal = {Journal of Climate}, year = {2013}, volume = {26}, number = {21}, pages = {85458555}, doi = {10.1175/JCLID1300060.1} } 

Abstract: Interfacial flows close to a moving contact line are inherently multiscale. The shape of the interface and the flow at meso and macroscopic scales inherit an apparent interface slope and a regularization length, both named after Voinov, from the microscopic inner region. Here, we solve the inner problem associated with the contact line motion for a volatile fluid at equilibrium with its vapor. The evaporation or condensation flux is then controlled by the dependence of the saturation temperature on interface curvaturethe socalled Kelvin effect. We derive the dependencies of the Voinov angle and of the Voinov length as functions of the parameters of the problem. We then identify the conditions under which the Kelvin effect is indeed the mechanism regularizing the contact line motion. 
BibTeX:
@article{Janecek2013, author = {Janecek, V. and Andreotti, B. and Prazak, D. and Barta, T. and Nikolayev, V. S.}, title = {Moving contact line of a volatile fluid}, journal = {Physical Review E}, year = {2013}, volume = {88}, number = {6}, pages = {060404}, doi = {10.1103/PhysRevE.88.060404} } 

Abstract: This theoretical and numerical study deals with evaporation of a fluid wedge in contact with its pure vapor. The model describes a regime where the continuous wetting film is absent and the actual line of the triple gasliquidsolid contact appears. A constant temperature higher than the saturation temperature is imposed at the solid substrate. The fluid flow is solved in the lubrication approximation. The introduction of the surface forces in the case of the partial wetting is discussed. The apparent contact angle (the gasliquid interface slope far from the contact line) is studied numerically as a function of the substrate superheating, contact line velocity, and parameters related to the solidfluid interaction (Young and microscopic contact angles, Hamaker constant, etc.). The dependence of the apparent contact angle on the substrate temperature is in agreement with existing approaches. For water, the apparent contact angle may be 20 degrees larger than the Young contact angle for 1 K superheating. The effect of the surface forces on the apparent contact angle is found to be weak. DOI: 10.1103/PhysRevE.87.012404 
BibTeX:
@article{Janecek2013b, author = {Janecek, V. and Nikolayev, V. S.}, title = {Apparentcontactangle model at partial wetting and evaporation: Impact of surface forces}, journal = {Physical Review E}, year = {2013}, volume = {87}, number = {1}, doi = {10.1103/PhysRevE.87.012404} } 

Abstract: Predicting dynamo selfgeneration in liquid metal experiments has been an ongoing question for many years. In contrast to simple dynamical systems for which reliable techniques have been developed, the ability to predict the dynamo capacity of a flow and the estimate of the corresponding critical value of the magnetic Reynolds number (the control parameter of the instability) has been elusive, partly due to the high level of turbulent fluctuations of flows in such experiments (with kinetic Reynolds numbers in excess of 10(6)). We address these issues here, using the von Karman sodium experiment and studying its response to an externally applied magnetic field. We first show that a dynamo threshold can be estimated from analysis related to critical slowing down and susceptibility divergence, in configurations for which dynamo action is indeed observed. These approaches are then applied to flow configurations that have failed to selfgenerate magnetic fields within operational limits, and we quantify the dynamo capacity of these configurations. 
BibTeX:
@article{Miralles2013, author = {Miralles, Sophie and Bonnefoy, Nicolas and Bourgoin, Mickael and Odier, Philippe and Pinton, JeanFrancois and Plihon, Nicolas and Verhille, Gautier and Boisson, Jean and Daviaud, Francois and Dubrulle, Berengere}, title = {Dynamo threshold detection in the von Karman sodium experiment}, journal = {Physical Review E}, year = {2013}, volume = {88}, number = {1}, pages = {013002}, doi = {10.1103/PhysRevE.88.013002} } 

Abstract: We present results on neutron scattering in solid He4 in the range of parameters where supersolidity is observed. The measurements address, among other questions, the viability of one possible mechanism of supersolidity: via a metastable amorphous phase. We have attempted to observe a glassy phase by neutron scattering. We have found that it is impossible to do this by total scattering, as it would be common in a classical solid, due to an extremely large inelastic diffuse signal related to the anomalously strong zeropoint motion of helium atoms. This raises a general question on the interpretation of such scattering as the signature of an amorphous phase. Results from energyresolved elastic scattering are heavily influenced by multiple scattering of neutrons which may be the major contribution to the measured elastic signal, but allow to put the limit on the concentration of an amorphous phase to less than or similar to 5% in a polycrystal with millimetersize crystallites and to less than or similar to 2% in a single crystal. The values of NCRIf, expected from these limits should be much lower, although exact values depend strongly on a particular model of glassrelated supersolidity. Copyright (C) Europhysics Letters A, 2013 
BibTeX:
@article{Mukharsky2013, author = {Mukharsky, Y. and Braslau, A. and Bossy, J. and Hansen, T. and Koza, M. M.}, title = {Static and dynamic structure factor in solid He4: Absence of a glassy phase}, journal = {Europhysics Letters}, year = {2013}, volume = {101}, number = {2}, doi = {10.1209/02955075/101/26002} } 

Abstract: To understand the oscillations in the real, multibranch pulsating heat pipe (PHP), the startup conditions of the single branch PHP with no adiabatic section are studied theoretically and numerically. The single branch PHP is a capillary open from one end, which is connected to a reservoir at constant pressure. A gas bubble is confined between the sealed end of the capillary and the liquid. The gas is the vapor of the liquid. The gas end of the capillary is maintained at a constant temperature larger than that of the liquid end. Under certain conditions, selfsustained oscillations of the meniscus may exist in such a system. The conditions of oscillation development (i.e. of the PHP startup) are obtained via the stability analysis of an earlier proposed theoretical model. The linear instability is absent in such a system. The instability of a marginal state described by piecewise linear equations is analyzed with the analytical averaging method. The instability boundary is presented in terms of dimensionless groups, the physical significance of which is discussed. It is found that the model describes correctly the known experimental facts. Some predictions concerning the instability threshold are formulated. (C) 2013 Elsevier Ltd. All rights reserved. 
BibTeX:
@article{Nikolayev2013, author = {Nikolayev, Vadim S.}, title = {Oscillatory instability of the gasliquid meniscus in a capillary under the imposed temperature difference}, journal = {International Journal of Heat and Mass Transfer}, year = {2013}, volume = {64}, pages = {313321}, doi = {10.1016/j.ijheatmasstransfer.2013.04.043} } 

Abstract: We report an experimental study on the transition between a disordered liquidlike state and an ordered solidlike one, in a collection of magnetically interacting macroscopic grains. A monolayer of magnetized particles is vibrated vertically at a moderate density. At high excitation a disordered, liquidlike state is observed. When the driving dimensionless acceleration Gamma is quasistatically reduced, clusters of ordered grains grow below a critical value, Gamma(c). These clusters have a welldefined hexagonal and compact structure. If the driving is subsequently increased, these clusters remain stable up to a higher critical value, Gamma(l). Thus, the solidliquid transition exhibits a hysteresis cycle. However, the lower onset Gamma(c) is not well defined as it depends strongly on the acceleration ramp speed and also on the magnetic interaction strength. Metastability is observed when the driving is rapidly quenched from high acceleration, Gamma > Gamma(l), to a low final excitation, Gamma(q). After this quench, solid clusters nucleate after a time lag, tau(o), either immediately (tau(o) = 0) or after some time lag (tau(o) > 0) that can vary from seconds up to several hundreds of seconds. The immediate growth occurs below a particular acceleration value, Gamma(s) (less than or similar to Gamma(c)). In all cases, for t >= tau(o) a solid cluster's temporal growth can be phenomenologically described by a stretched exponential law. The evolution of the parameters of this law as a function of Gamma(q) is presented and the values of fitted parameters are discussed. DOI: 10.1103/PhysRevE.87.022204 
BibTeX:
@article{Oyarte2013, author = {Oyarte, Loreto and Gutierrez, Pablo and Aumaitre, Sebastien and Mujica, Nicolas}, title = {Phase transition in an outofequilibrium monolayer of dipolar vibrated grains}, journal = {Physical Review E}, year = {2013}, volume = {87}, number = {2}, doi = {10.1103/PhysRevE.87.022204} } 

Abstract: The effect of material parameters on the statistics of fracture surfaces is analyzed under small scale yielding conditions. Three dimensional calculations of ductile crack growth under mode I plane strain, small scale yielding conditions are carried out using an elasticviscoplastic constitutive relation for a progressively cavitating plastic solid with two populations of void nucleating second phase particles represented. Large particles that result in void nucleation at an early stage are modeled discretely while small particles that require large strains to nucleate are homogeneously distributed. The three dimensional analysis permits modeling of a three dimensional material microstructure and of the resulting three dimensional stress and deformation states that develop in the fracture process region. Material parameters characterizing void nucleation are varied and the statistics of the resulting fracture surfaces is investigated. All the fracture surfaces are found to be selfaffine over a size range of about two orders of magnitude with a very similar roughness exponent of . In contrast, the full statistics of the fracture surfaces is found to be more sensitive to the material microscopic fracture properties: height fluctuations are shown to crossover from a Student's distribution with power law tails at small scales to a Gaussian behavior at large scales, but this transition occurs at a material dependent length scale. Using the family of Student's distributions, this transition can be described introducing an additional exponent , the value of which compares well with recent experimental findings. The description of the roughness distribution used here gives a more complete quantitative characterization of the fracture surface morphology which allows a better comparison with experimental data and an easier interpretation of the roughness properties in terms of microscopic failure mechanisms. 
BibTeX:
@article{Ponson2013, author = {Ponson, L. and Cao, Y. and Bouchaud, E. and Tvergaard, V. and Needleman, A.}, title = {Statistics of ductile fracture surfaces: the effect of material parameters}, journal = {Internalional Journal of Fracture}, year = {2013}, volume = {184}, number = {12, SI}, pages = {137149}, doi = {10.1007/s107040139846z} } 

Abstract: Many faults and fractures in various natural and manmade materials share a remarkable common fractal property in their morphology. We report on the roughness of faults in rocks by analyzing the outofplane fluctuations of slip surfaces. They display a statistical powerlaw relationship with a nearly constant fractal exponent from millimeter scale microfractures in fault zones to coastlines measuring thousands of kilometers that have recorded continental breakup. A possible origin of this striking fractal relationship over 11 orders of magnitude of length scales is that all faulting processes in rocks share common characteristics that play a crucial role in the shaping of fault surfaces, such as the effects of elastic longrange stress interactions and stress screening by mechanical heterogeneities during quasistatic fracture growth. Citation: Renard, F., T. Candela, and E. Bouchaud (2013), Constant dimensionality of fault roughness from the scale of microfractures to the scale of continents, Geophys. Res. Lett., 40, 8387, doi: 10.1029/2012GL054143. 
BibTeX:
@article{Renard2013, author = {Renard, F. and Renard, T. and Bouchaud, E.}, title = {Constant dimensionality of fault roughness from the scale of microfractures to the scale of continents}, journal = {Geophysical Research Letters}, year = {2013}, volume = {40}, number = {1}, pages = {8387}, doi = {10.1029/2012GL054143} } 

Abstract: We study the influence on steady turbulent states of the forcing in a von Karman flow, at constant impeller speed, or at constant torque. We find that the different forcing conditions change the nature of the stability of the steady states and reveal dynamical regimes that bear similarities to lowdimensional systems. We suggest that this forcing dependence may be applicable to other turbulent systems. 
BibTeX:
@article{SaintMichel2013, author = {SaintMichel, B. and Dubrulle, B. and Marie, L. and Ravelet, F. and Daviaud, F.}, title = {Evidence for forcingdependent steady states in a turbulent swirling flow.}, journal = {Physical Review Letters}, year = {2013}, volume = {111}, number = {23}, pages = {234502234502}, url = {journals.aps.org/prl/abstract/10.1103/PhysRevLett.111.234502}, doi = {10.1103/PhysRevLett.111.234502} } 

Abstract: We demonstrate experimentally the existence of a purely elastic, nonviscous fingering instability which arises when air penetrates into an elastomer confined in a HeleShaw cell. Fingers appear sequentially and propagate within the bulk of the material as soon as a critical strain, independent of the elastic modulus, is exceeded. Key elements in the driving force of the instability are the confinement of the gel and its adhesion to the plates of the cell, which result in a considerable expense of elastic energy during the growth of the air bubble. 
BibTeX:
@article{Saintyves2013, author = {Saintyves, B. and Dauchot, O. and Bouchaud, E.}, title = {Bulk Elastic Fingering Instability in HeleShaw Cells}, journal = {Physical Review Letters}, year = {2013}, volume = {111}, number = {4}, doi = {10.1103/PhysRevLett.111.047801} } 

Abstract: We study the influence on steady turbulent states of the forcing in a von Karman flow, at constant impeller speed, or at constant torque. We find that the different forcing conditions change the nature of the stability of the steady states and reveal dynamical regimes that bear similarities to lowdimensional systems. We suggest that this forcing dependence may be applicable to other turbulent systems. 
BibTeX:
@article{StMichel2013, author = {StMichel, B. and Dubrulle, B. and Marie, L. and Ravelet, F. and Daviaud, F.}, title = {Evidence for ForcingDependent Steady States in a Turbulent Swirling Flow}, journal = {Physical Review Letters}, year = {2013}, volume = {111}, number = {23}, doi = {10.1103/PhysRevLett.111.234502} } 

Abstract: show, using covariant Lyapunov vectors in addition to standard Lyapunov analysis, that there exists a set of collective Lyapunov modes in large chaotic systems exhibiting collective dynamics. Associated with delocalized Lyapunov vectors, they act collectively on the trajectory and hence characterize the instability of its collective dynamics. We further develop, for globally coupled systems, a connection between these collective modes and the Lyapunov modes in the corresponding PerronFrobenius equation. We thereby address the fundamental question of the effective dimension of collective dynamics and discuss the extensivity of chaos in the presence of collective dynamics. 
BibTeX:
@article{Takeuchi2013, author = {Takeuchi, Kazumasa A. and Chate, Hugues}, title = {Collective Lyapunov modes}, journal = {Journal of Physics Amathematical and Theoretical}, year = {2013}, volume = {46}, number = {25}, pages = {254007}, doi = {10.1088/17518113/46/25/254007} } 

Abstract: Vibrated polar disks have been used experimentally to investigate collective motion of driven particles, where fully ordered asymptotic regimes could not be reached. Here we present a model reproducing quantitatively the single, binary, and collective properties of this granular system. Using system sizes not accessible in the laboratory, we show in silico that true longrange order is possible in the experimental system. Exploring the model's parameter space, we find a phase diagram qualitatively different from that of dilute or pointlike particle systems. 
BibTeX:
@article{Weber2013, author = {Weber, C. A. and Hanke, T. and Deseigne, J. and Leonard, S. and Dauchot, O. and Frey, E. and Chate, H.}, title = {LongRange Ordering of Vibrated Polar Disks}, journal = {Physical Review Letters}, year = {2013}, volume = {110}, number = {20}, doi = {10.1103/PhysRevLett.110.208001} } 