A model for Faraday pilot waves over variable topography

Posted by on Jan 22, 2017 in Bibliography, Core Bibliography, Numerical Simulation, Theory Bibliography | 0 comments

Abstract : Couder et al. (Nature, vol. 437 (7056), 2005, p. 208) discovered that droplets walking on a vibrating bath possess certain features previously thought to be exclusive to quantum systems. These millimetric droplets synchronize with their Faraday wavefield, creating a macroscopic pilot-wave system. In this paper we exploit the fact that the waves generated are nearly monochromatic and propose a hydrodynamic model capable of quantitatively capturing the interaction between bouncing drops and a variable topography. We show that our reduced model is able to reproduce some important experiments involving the drop–topography interaction, such as non-specular reflection and single-slit diffraction.

Faria, L. M. (2017). A model for Faraday pilot waves over variable topography. Journal of Fluid Mechanics, 811, 51-66.

77.Wave Reflection

https://www.cambridge.org/

 

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Non-specular reflection of walking droplets

Posted by on Jan 22, 2017 in Bibliography, Core Bibliography | 0 comments

Abstract : Since their discovery by Yves Couder and Emmanuel Fort, droplets walking on a vibrating liquid bath have attracted considerable attention because they unexpectedly exhibit certain features reminiscent of quantum particles. While the behaviour of walking droplets in unbounded geometries has to a large extent been rationalized theoretically, no such rationale exists for their behaviour in the presence of boundaries, as arises in a number of key quantum analogue systems. We here present the results of a combined experimental and theoretical study of the interaction of walking droplets with a submerged planar barrier. Droplets exhibit non-specular reflection, with a small range of reflection angles that is only weakly dependent on the system parameters, including the angle of incidence. The observed behaviour is captured by simulations based on a theoretical model that treats the boundaries as regions of reduced wave speed, and rationalized in terms of momentum considerations.

Pucci, G., Sáenz, P. J., Faria, L. M., & Bush, J. W. (2016). Non-specular reflection of walking droplets. J Fluid Mech, 804, R3.

69.reflection

 

 

http://math.mit.edu/~bush/wordpress/wp-content/uploads/2016/09/Pucci-JFM-2016.pdf

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Self-attraction into spinning eigenstates of a mobile wave source by its emission back-reaction

Posted by on Jan 22, 2017 in Bibliography, Core Bibliography | 0 comments

Abstract : The back-reaction of a radiated wave on the emitting source is a general problem. In the most general case, back-reaction on moving wave sources depends on their whole history. Here we study a model system in which a pointlike source is piloted by its own memory-endowed wave field. Such a situation is implemented experimentally using a self-propelled droplet bouncing on a vertically vibrated liquid bath and driven by the waves it generates along its trajectory. The droplet and its associated wave field form an entity having an intrinsic dual particle-wave character. The wave field encodes in its interference structure the past trajectory of the droplet. In the present article we show that this object can self-organize into a spinning state in which the droplet possesses an orbiting motion without any external interaction. The rotation is driven by the wave-mediated attractive interaction of the droplet with its own past. The resulting “memory force” is investigated and characterized experimentally, numerically, and theoretically. Orbiting with a radius of curvature close to half a wavelength is shown to be a memory-induced dynamical attractor for the droplet’s motion.

Labousse, M., Perrard, S., Couder, Y., & Fort, E. (2016). Self-attraction into spinning eigenstates of a mobile wave source by its emission back-reaction. Physical Review E, 94(4), 042224.

self orbiting

Available on ResearchGate (Free login required)

 

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Onset of chaos in orbital pilot-wave dynamics

Posted by on Jan 15, 2017 in Bibliography, Core Bibliography, Numerical Simulation | 0 comments

Abstract  : We examine the orbital dynamics of droplets self-propelling along the surface of a vibrating bath. Circular orbital motion may arise when the walking droplet is subjected to one of three external force fields, the Coriolis force, a simple harmonic force, and a Coulomb force. Particular attention is given to a theoretical characterization of the onset of chaos that accompanies the destabilization of such circular orbits.

Tambasco, L., Harris, D., Oza, A., Rosales, R., & Bush, J. (2015, November). Onset of chaos in orbital pilot-wave dynamics. In APS Meeting Abstracts.

Onset of Chaos Numerical

 

Paper available on researchgate.net/ (Requires free login)

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Surface topography measurements of the bouncing droplet experiment

Posted by on Dec 4, 2016 in Bibliography, Core Bibliography | 0 comments

A technical entry by the american team reproducing the synthetic Schlieren free surface measurment already implemented successfully by the Paris Team.

Damiano, A. P., Brun, P. T., Harris, D. M., Galeano-Rios, C. A., & Bush, J. W. (2016). Surface topography measurements of the bouncing droplet experiment. Experiments in Fluids, 57(10), 163.

Abstract
A free-surface synthetic Schlieren (Moisy et al. in Exp Fluids 46:1021–1036, 2009; Eddi et al. in J Fluid Mech 674:433–463, 2011) technique has been implemented in order to measure the surface topography generated by a droplet bouncing on a vibrating fluid bath. This method was used to capture the wave fields of bouncers, walkers, and walkers interacting with boundaries. These wave profiles are compared with existing theoretical models and simulations and will prove valuable in guiding their future development. Specifically, the method provides insight into what type of boundary conditions apply to the wave field when a bouncing droplet approaches a submerged obstacle.
73.surface topography measurment
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Momentum exchange in the electron double-slit experiment

Posted by on Nov 29, 2016 in Bibliography, Core Bibliography | 0 comments

Yet another report of failure in trying to reproduce the single particle slit diffraction experiment with walking droplets

Batelaan, H., Jones, E., Huang, W. C. W., & Bach, R. (2016). Momentum exchange in the electron double-slit experiment.

Abstract. We provide support for the claim that momentum is conserved for individual events in the electron double slit experiment. The natural consequence is that a physical mechanism is responsible for this momentum exchange, but that even if the fundamental mechanism is known for electron crystal diffraction and the Kapitza–Dirac effect, it is unknown for electron diffraction from nano-fabricated double slits. Work towards a proposed explanation in terms of particle trajectories affected by a vacuum field is discussed. The contentious use of trajectories is discussed within the context of oil droplet analogues of double slit diffraction.

http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1010&context=physicsbatelaan

Momentum exchange in the electron double-slit experiment

 

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Double-slit experiment with single wave-driven particles and its relation to quantum mechanics

Posted by on Oct 12, 2016 in Bibliography, Core Bibliography | 0 comments

Andersen, A., Madsen, J., Reichelt, C., Ahl, S. R., Lautrup, B., Ellegaard, C., … & Bohr, T. (2015). Double-slit experiment with single wave-driven particles and its relation to quantum mechanics. Physical Review E, 92(1), 013006.

ABSTRACT :

In a thought-provoking paper, Couder and Fort [Phys. Rev. Lett. 97, 154101 (2006)] describe a version of the famous double-slit experiment performed with droplets bouncing on a vertically vibrated fluid surface. In the experiment, an interference pattern in the single-particle statistics is found even though it is possible to determine unambiguously which slit the walking droplet passes. Here we argue, however, that the single-particle statistics in such an experiment will be fundamentally different from the single-particle statistics of quantum mechanics. Quantum mechanical interference takes place between different classical paths with precise amplitude and phase relations. In the double-slit experiment with walking droplets, these relations are lost since one of the paths is singled out by the droplet. To support our conclusions, we have carried out our own double-slit experiment, and our results, in particular the long and variable slit passage times of the droplets, cast strong doubt on the feasibility of the interference claimed by Couder and Fort. To understand theoretically the limitations of wave-driven particle systems as analogs to quantum mechanics, we introduce a Schrödinger equation with a source term originating from a localized particle that generates a wave while being simultaneously guided by it. We show that the ensuing particle-wave dynamics can capture some characteristics of quantum mechanics such as orbital quantization. However, the particle-wave dynamics can not reproduce quantum mechanics in general, and we show that the single-particle statistics for our model in a double-slit experiment with an additional splitter plate differs qualitatively from that of quantum mechanics.

 

70. Double-slit experiment with single wave-driven particles and its relation to quantum mechanics.

 

http://sci-hub.bz/10.1103/physreve.92.013006#

 

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Shedding light on pilot-wave phenomena

Posted by on Sep 17, 2016 in Bibliography, Core Bibliography, Videos | 0 comments

Brun, P. T., Harris, D. M., Prost, V., Quintela, J., & Bush, J. W. (2016). Shedding light on pilot-wave phenomena. Physical Review Fluids, 1(5), 050510.

 

ABSTRACT

This paper is associated with a video winner of a 2015 APS/DFD Gallery of Fluid Motion Award. The original video is available from the Gallery of Fluid Motion,

http://dx.doi.org/10.1103/APS.DFD.2015.GFM.V0064

68.Shedding light on pilot-wave phenomena

http://link.aps.org/pdf/10.1103/PhysRevFluids.1.050510

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Neimark–Sacker bifurcation and evidence of chaos in a discrete dynamical model of walkers

Posted by on Sep 17, 2016 in Bibliography, Theory Bibliography | 0 comments

Rahman, A., & Blackmore, D. (2015). Neimark–Sacker bifurcation and evidence of chaos in a discrete dynamical model of walkers. arXiv preprint arXiv:1507.08057.

ABSTRACT

Bouncing droplets on a vibrating fluid bath can exhibit wave-particle behavior, such as being propelled by interacting with its own wave field. These droplets seem to walk across the bath, and thus are dubbed walkers. Experiments have shown that walkers can exhibit exotic dynamical behavior indicative of chaos. While the integro-differential models developed for these systems agree well with the experiments, they are difficult to analyze mathematically. In recent years, simpler discrete dynamical models have been derived and studied numerically. The numerical simulations of these models show evidence of exotic dynamics such as period doubling bifurcations, Neimark–Sacker (N–S) bifurcations, and even chaos. For example, in [Gilet, PRE 2014], based on simulations Gilet conjectured the existence of a supercritical N-S bifurcation as the damping factor in his one-dimensional path model. We prove Gilet’s conjecture and more; in fact, both supercritical and subcritical (N-S) bifurcations are produced by separately varying the damping factor and wave-particle coupling for all eigenmode shapes. Then we compare our theoretical results with some previous and new numerical simulations, and find complete qualitative agreement. Furthermore, evidence of chaos is shown by numerically studying a global bifurcation.

 

66.Neimark--Sacker bifurcation and evidence of chaos in a discrete dynamical model of walkers

http://arxiv.org/pdf/1507.08057

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Wave-Based Turing Machine: Time Reversal and Information Erasing

Posted by on Sep 17, 2016 in Bibliography, Core Bibliography | 0 comments

Perrard, S., Fort, E., & Couder, Y. (2016). Wave-Based Turing Machine: Time Reversal and Information Erasing. Physical Review Letters, 117(9), 094502.

 

ABSTRACT

The investigation of dynamical systems has revealed a deep-rooted difference between waves and objects regarding temporal reversibility and particlelike objects. In nondissipative chaos, the dynamic of waves always remains time reversible, unlike that of particles. Here, we explore the dynamics of a wave-particle entity. It consists in a drop bouncing on a vibrated liquid bath, self-propelled and piloted by the surface waves it generates. This walker, in which there is an information exchange between the particle and the wave, can be analyzed in terms of a Turing machine with waves as the information repository. The experiments reveal that in this system, the drop can read information backwards while erasing it. The drop can thus backtrack on its previous trajectory. A transient temporal reversibility, restricted to the drop motion, is obtained in spite of the system being both dissipative and chaotic.

 

67.Wave-Based Turing Machine Time Reversal and Information Erasing

Available at Researchgate (requires free login)

https://www.researchgate.net/publication/307082497_Wave-Based_Turing_Machine_Time_Reversal_and_Information_Erasing

 

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Transition Orbits of Walking Droplets

Posted by on Aug 15, 2016 in Bibliography, Core Bibliography | 0 comments

Parker, J. (2015). Transition Orbits of Walking Droplets (Doctoral dissertation, California Polytechnic State University, San Luis Obispo).

“It was recently discovered that millimeter-sized droplets bouncing on the surface of an oscillating bath of the same fluid can couple with the surface waves it produces and begin walking across the fluid bath. These walkers have been shown to behave similarly to quantum particles; a few examples include single-particle diffraction, tunneling, and quantized orbits. Such behavior occurs because the drop and surface waves depend on each other to exist, making this the first and only known macroscopic pilot-wave system. In this paper, the quantized orbits between two identical drops are explored. By sending a perturbation to a pair of orbiting walkers, the orbit can be disrupted and transition to a new orbit. The numerical results of such transitions are analyzed and discussed.”

 

TWO interesting things in this small report :

1 – Influence of apparatus temperature on the faraday thresold

65.transition orbits of walking droplets.temperature and faraday Thresold

2 – sending a plane wave towards a 2-droplet orbiting system can cause a shift in the orbit quantization

65.transition orbits of walking droplets

https://www.semanticscholar.org/

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Quantumlike statistics of deterministic waveparticle interactions in a circular cavity

Posted by on Jul 13, 2016 in Bibliography, Core Bibliography, Numerical Simulation, Theory Bibliography | 0 comments

Gilet, T. (2016). Quantumlike statistics of deterministic wave-particle interactions in a circular cavity. Physical Review E, 93(4), 042202.
A deterministic low-dimensional iterated map is proposed here to describe the interaction between a bouncing droplet and Faradaywaves confined to a circular cavity. Its solutions are investigated theoretically and numerically. The horizontal trajectory of the droplet can be chaotic: it then corresponds to a random walk of average step size equal to half the Faraday wavelength. An analogy is made between the diffusion coefficient of this random walk and the action per unit mass /m of a quantum particle. The statistics of droplet position and speed are shaped by the cavity eigenmodes, in remarkable agreement with the solution of Schr¨odinger equation for a quantum particle in a similar potential well.
neumann eigenmodes
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Faraday wave lattice as an elastic metamaterial

Posted by on May 22, 2016 in Bibliography, Core Bibliography | 0 comments

Domino, L., Tarpin, M., Patinet, S., & Eddi, A. (2016). Faraday wave lattice as an elastic metamaterial. arXiv preprint arXiv:1601.08024.

(Also on PhysRev E.)

Metamaterials enable the emergence of novel physical properties due to the existence of an underlying sub-wavelength structure. Here, we use the Faraday instability to shape the uid-air interface with a regular pattern. This pattern undergoes an oscillating secondary instability and exhibits spontaneous vibrations that are analogous to transverse elastic waves. By locally forcing these waves, we fully characterize their dispersion relation and show that a Faraday pattern presents an
e ffective shear elasticity. We propose a physical mechanism combining surface tension with the Faraday structured interface that quantitatively predicts the elastic wave phase speed, revealing that the liquid interface behaves as an elastic metamaterial.

Faraday wave lattice as an elastic metamaterial

 

http://arxiv.org/pdf/1601.08024.pdf

 

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Scattering theory of walking droplets in the presence of obstacles

Posted by on May 22, 2016 in Bibliography, Core Bibliography, Theory Bibliography | 0 comments

Dubertrand, R., Hubert, M., Schlagheck, P., Vandewalle, N., Bastin, T., & Martin, J. (2016). Scattering theory of walking droplets in the presence of obstacles. arXiv preprint arXiv:1605.02370.

We aim to describe a droplet bouncing on a vibrating bath. Due to Faraday instability a surface wave is created at each bounce and serves as a pilot wave of the droplet. This leads to so called walking droplets or walkers. Since the seminal experiment by Couder et al [Phys. Rev. Lett. 97, 154101 (2006)] there have been many attempts to accurately reproduce the experimental results. Here we present a simple and highly versatile model inspired from quantum mechanics. We propose to describe the trajectories of a walker using a Green function approach. The Green function is related to Helmholtz equation with Neumann boundary conditions on the
obstacle(s) and outgoing conditions at infinity. For a single slit geometry our model is exactly solvable and reproduces some general features observed experimentally. It
stands for a promising.

Scattering theory of walking droplets in the presence of obstacles

http://arxiv.org/pdf/1605.02370.pdf

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Nonlinear Generation of Vorticity by Surface Waves

Posted by on May 21, 2016 in Bibliography, Extended Bibliography | 0 comments

Filatov, S. V., Parfenyev, V. M., Vergeles, S. S., Brazhnikov, M. Y., Levchenko, A. A., & Lebedev, V. V. (2016). Nonlinear Generation of Vorticity by Surface Waves. Physical review letters, 116(5), 054501.

We demonstrate that waves excited on a fluid surface produce local surface rotation owing to hydrodynamic nonlinearity. We examine theoretically the effect and obtain an explicit formula for the vertical vorticity in terms of the surface elevation. Our theoretical predictions are confirmed by measurements of surface motion in a cell with water where surface waves are excited by vertical and harmonic shaking the cell. The experimental data are in good agreement with the theoretical predictions. We discuss physical consequences of the effect.

Nonlinear Generation of Vorticity by Surface Waves

http://ssver.itp.ac.ru/site/publications/Filatov_2016_PRL.pdf

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Pilot-wave dynamics in a harmonic potential : Quantization and stability of circular orbits

Posted by on May 2, 2016 in Bibliography, Core Bibliography, Theory Bibliography | 0 comments

Labousse, M., Oza, A. U., Perrard, S., & Bush, J. W. (2016). Pilot-wave dynamics in a harmonic potential: Quantization and stability of circular orbits.Physical Review E, 93(3), 033122.

“We present the results of a theoretical investigation of the dynamics of a droplet walking on a vibrating fluid bath under the influence of a harmonic potential. The walking droplet’s horizontal motion is described by an integro-differential trajectory equation, which is found to admit steady orbital solutions. Predictions for the dependence of the orbital radius and frequency on the strength of the radial harmonic force field agree favorably with experimental data. The orbital quantization is rationalized through an analysis of the orbital solutions. The predicted dependence of the orbital stability on system parameters is compared with experimental data and the limitations of the model are discussed.”

Pilot-wave dynamics in a harmonic potential Quantization and stability of circular orbits

 

http://arxiv.org/pdf/1604.07394

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Faraday pilot wave dynamics : modelling and computation

Posted by on Apr 10, 2016 in Bibliography, Core Bibliography, Numerical Simulation | 0 comments

Milewski, P. A., Galeano-Rios, C. A., Nachbin, A., & Bush, J. W. (2015). Faraday pilot-wave dynamics: modelling and computation. Journal of Fluid Mechanics, 778, 361-388.

A millimetric droplet bouncing on the surface of a vibrating fluid bath can self-propel by virtue of a resonant interaction with its own wave field. This system represents the first known example of  pilot-wave system of the form envisaged by Louis de Broglie in his double-solution pilot-wave theory. We here develop a fluid model of pilot-wave hydrodynamics by coupling recent models of the droplet’s bouncing dynamics with a more realistic model of weakly viscous quasi-potential wave generation and evolution. The resulting model is the first to capture a number of features reported in experiment, including the rapid transient wave generated during impact, the Doppler effect and walker–walker interactions.

faraday pilot wave dynamics modelling and computation

https://www.researchgate.net/profile/Paul_Milewski/publication/281111731_Faraday_pilot-wave_dynamics_Modelling_and_computation/links/55ebf4b208ae21d099c5ec8a.pdf

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Dynamics and statistics of wave-particle interactions in a confined geometry

Posted by on Apr 10, 2016 in Bibliography, Core Bibliography, Numerical Simulation | 0 comments

Gilet, T. (2014). Dynamics and statistics of wave-particle interactions in a confined geometry. Physical Review E, 90(5), 052917.

A walker is a droplet bouncing on a liquid surface and propelled by the waves that it generates. This macroscopic wave-particle association exhibits behaviors reminiscent of quantum particles. This article presents a toy model of the coupling between a particle and a confined standing wave. The resulting 2D iterated map captures many features of the walker dynamics observed in different configurations of confinement. These features include the time decomposition of the chaotic trajectory in quantized eigenstates, and the particle statistics being shaped by the wave. It shows that deterministic wave-particle coupling expressed in its simplest form can account for some quantumlike behaviors.

Dynamics and statistics of wave-particle interactions in a confined geometry

https://orbi.ulg.ac.be/bitstream/2268/178755/2/Generic.pdf

 

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Displacement of an Electrically Charged Drop on a Vibrating Bath

Posted by on Apr 10, 2016 in Bibliography, Extended Bibliography | 0 comments

Brandenbourger, M., Vandewalle, N., & Dorbolo, S. (2016). Displacement of an Electrically Charged Drop on a Vibrating Bath. Physical review letters, 116(4), 044501.

In this work, the manipulation of an electrically charged droplet bouncing on a vertically vibrated, bath is investigated. When a horizontal, uniform and static electric eld is applied to it, a motion is induced. The droplet is accelerated when the droplet is small. On the other hand, large droplets appear to move with a constant speed that depends linearly on the applied electrical eld. In the latter regime, high speed imaging of one bounce reveals that the droplet experiences an acceleration due to the electrical force during the ight and decelerates to zero when interacting with the surface of the bath. Thus, the droplet moves with a constant average speed on a large time scale. We propose a criterion based on the force necessary to move a charged droplet at the surface of the
bath to discriminate between constant speed and accelerated droplet regimes.

Displacement of an Electrically Charged Drop on a Vibrating Bath

 

http://orbi.ulg.ac.be/bitstream/2268/194253/1/PhysRevLett.116.044501.pdf

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Smoothed Particles Hydrodynamics numerical simulations of droplets walking on viscous vibrating fluid

Posted by on Jan 25, 2016 in Bibliography, Core Bibliography, Numerical Simulation | 0 comments

Molteni, D., Vitanza, E., & Battaglia, O. R. (2016). Smoothed Particles Hydrodynamics numerical simulations of droplets walking on viscous vibrating fluid. arXiv preprint arXiv:1601.05017.

Abstract :

“We study the phenomenon of the “walking droplet”, by means of numerical fluid dynamics simulations using a standard version of the Smoothed Particle Hydrodynamics method. The phenomenon occurs when a millimetric drop is released on the surface of an oil of the same composition contained in a container subjected to vertical oscillations of frequency and amplitude close to the Faraday instability threshold. At appropriate values of the parameters of the system under study, the liquid drop jumps permanently on the surface of the vibrating fluid forming a localized wave-particle system, reminding the behavior of a wave particle quantum system as suggested by de Broglie. In the simulations, the drop and the wave travel at nearly constant speed, as observed in experiments. In our study we made relevant simplifying assumptions, however we observe that the wave-drop coupling is easily obtained. This fact suggests that the phenomenon may occur in many contexts and opens the possibility to study the phenomenon in an extremely wide range of physical configurations.”

 

http://arxiv.org/ftp/arxiv/papers/1601/1601.05017.pdf

sph

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