Article
Chemistry, Multidisciplinary
Atakan B. Ari, M. Selim Hanay, Mark R. Paul, Kamil L. Ekinci
Summary: In this study, the spectral characteristics of the thermal force causing Brownian motion in a nanomechanical beam resonator in a viscous liquid are investigated. The measured power spectral density and linear response of the resonator help determine the colored spectrum of the Brownian force noise at different frequencies, following the fluctuation-dissipation theorem of statistical mechanics.
Article
Engineering, Mechanical
Cheng Ma, Ruibin Ren, Maokang Luo, Ke Deng
Summary: This paper investigates a linear oscillator subject to multiplicative Gaussian white noise in both frequency and input signal fluctuation. The focus of the study is the stochastic resonance (SR). By utilizing the properties of Brownian motion and Ito formula, the analytical expressions of both the first-order and second-order moments of the system's steady response are derived. The signal-to-noise ratio is introduced to analyze the impact of fluctuation in the system. It is noteworthy that the generalized Langevin equation is solved using mathematical methods. Meanwhile, the variation of the output amplitude with system parameters is discussed. It is found that there is no SR in the first-order moment expression, while both SR and inverse stochastic resonance phenomena exist in the second-order moment expression, which have not been reported in previous studies.
NONLINEAR DYNAMICS
(2022)
Article
Physics, Multidisciplinary
Benjamin De Bruyne, Satya N. Majumdar, Gregory Schehr
Summary: The proposed method generates bridge run-and-tumble trajectories with specified starting and ending conditions for different types of constrained particles, showing high efficiency in numerical implementation.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2021)
Article
Physics, Particles & Fields
N. A. Lemos, D. Mueller, M. J. Reboucas
Summary: This paper discusses the assumption of orientability in spacetime and proposes a method to explore the orientability of spacetime using quantum vacuum electromagnetic fluctuations.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Physics, Particles & Fields
Nathan G. Caldeira, Eduardo Folco Capossoli, Carlos A. D. Zarro, Henrique Boschi-Filho
Summary: In this work, we studied the fluctuations and dissipation of a string in a deformed AdS space at finite temperature and density. By calculating the correlation functions and mean square displacement, we analyzed the behavior and verified the fluctuation-dissipation theorem.
EUROPEAN PHYSICAL JOURNAL C
(2022)
Article
Computer Science, Interdisciplinary Applications
Timothy A. Westwood, Blaise Delmotte, Eric E. Keaveny
Summary: This paper presents a generalized drift-correcting scheme for efficiently computing the random motion of micron and nanometre scale particles in overdamped fluids. The scheme seamlessly integrates with fast methods for computing hydrodynamic interactions and random increments, providing increased computational efficiency without sacrificing accuracy.
JOURNAL OF COMPUTATIONAL PHYSICS
(2022)
Article
Physics, Fluids & Plasmas
Maria de Jesus Martinez-Lopez, Jose Luis Arauz-Lara
Summary: The motion of colloidal species on an out-of-thermal equilibrium surface was experimentally studied using optical microscopy. Water droplets of submicrometer sizes, spontaneously formed at the interface between water and oil, were observed to move and grow without showing anomalous diffusion.
Article
Physics, Applied
Norio Inui, Kazunori Maebuchi
Summary: This study discovers that a graphene disk can be levitated above a magnet by a repulsive force generated from their diamagnetic interaction. The rotation of the graphene disk is also caused by the strong anisotropy of the magnetic permeability of graphene. The study further explains the dependence of the fluctuations of the position and angle of the levitated graphene disk on its size and temperature.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Optics
Konstantine Cheishvili, Jeroen Kalkman
Summary: We have developed a number fluctuation dynamic light scattering optical coherence tomography (OCT) technique to measure slow flows of dilute particle suspensions. Our method overcomes the limitations of conventional correlation-based OCT and provides more accurate velocity estimation. It can also determine the concentration of particles under flow and enables 2D sub-diffusion flow imaging using a scanning OCT system.
Article
Biochemistry & Molecular Biology
Francesco Rusciano, Raffaele Pastore, Francesco Greco
Summary: Recent works reveal that glass-forming liquids exhibit Fickian non-Gaussian diffusion, with non-Gaussian displacement distributions persisting even after attaining linearity in mean square displacement. These non-Gaussian deviations exhibit exponential tails with a growing decay length proportional to a power-law in time. The study examines data from different glass-forming systems and identifies a scaling law for the decay length, which holds for all systems regardless of dimensionality. Additionally, a universal characteristic time for the disappearance of exponential tails and the recovery of Gaussianity is found across different temperatures/concentrations within each system, related to the onset of Fickianity through a power-law.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Physics, Fluids & Plasmas
Elena Sese-Sansa, Demian Levis, Ignacio Pagonabarraga
Summary: In this study, a model system of repulsive self-propelled disks in two dimensions with ferromagnetic and nematic velocity alignment interactions is comprehensively analyzed. It is found that strong alignment leads to orientational order, while moderate alignment with high self-propulsion results in motility-induced phase separation (MIPS). The microscopic theory derived for these systems accurately predicts the occurrence of MIPS, showing the predictive power of such theories in describing complex active matter systems.
Article
Multidisciplinary Sciences
D. Cattiaux, I Golokolenov, S. Kumar, M. Sillanpaa, L. Mercier de Lepinay, R. R. Gazizulin, X. Zhou, A. D. Armour, O. Bourgeois, A. Fefferman, E. Collin
Summary: Passive cooling allows devices to reach equilibrium with their environment without excess damping. The authors demonstrate passive cooling of a 15 μm drum-head device with MHz fundamental flexure to its quantum ground state. The quantum-to-classical crossover remains one of the most challenging questions in science.
NATURE COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Manju Joseph, B. Anugop, K. R. Vijesh, Vipin Balan, V. P. N. Nampoori, M. Kailasnath
Summary: Nanofluids with suitable heat transfer properties have been found to be applicable in various fields. The heat transfer properties of these nanofluids are affected by the particle size, morphology, and concentration of nanoparticles. Different morphologies of zinc oxide nanofluids were synthesized and evaluated for their thermal properties. The findings suggest that casein-capped zinc oxide nanofluids exhibit excellent thermal insulation properties and have potential applications in thermal-related industries.
Article
Physics, Fluids & Plasmas
I. G. Marchenko, V. Aksenova, I. I. Marchenko, J. Luczka, J. Spiechowicz
Summary: We investigate the impact of temperature on the diffusion coefficient of an inertial Brownian particle in a symmetric periodic potential under the influence of a symmetric time-periodic force. It is observed that the diffusion coefficient exhibits giant damped quasiperiodic oscillations in the low-friction regime. Our research demonstrates that the diffusion coefficient increases at its minima when temperature rises, while it decreases at the maxima within a finite temperature range. This phenomenon can be explained by considering the perturbation of deterministic dynamics by thermal fluctuations and the mean residence time of the particle in locked and running trajectories. Moreover, we show that the temperature dependence of the diffusion coefficient can be accurately reconstructed using the stationary probability distribution of the running trajectories.
Article
Physics, Multidisciplinary
Zhiwu Liao, Yong Yu, Shaoxiang Hu
Summary: This paper analyzes the dependence among multi-layer convolutions by examining the gray levels of image pixels before, in, and after the convolutions. The pixels are transformed into modified multifractional Gaussian noise (mmfGn), and their Hurst parameters are calculated. The results show the presence of short-range dependence (SRD) or long-range dependence (LRD), providing valuable insights for designing better network structures and image processing algorithms.
FRONTIERS IN PHYSICS
(2022)
Article
Physics, Mathematical
Jerzy Luczka
JOURNAL OF STATISTICAL PHYSICS
(2020)
Article
Quantum Science & Technology
Noah Van Horne, Dahyun Yum, Tarun Dutta, Peter Haenggi, Jiangbin Gong, Dario Poletti, Manas Mukherjee
NPJ QUANTUM INFORMATION
(2020)
Article
Multidisciplinary Sciences
J. Spiechowicz, J. Luczka
Summary: Experimentalists have achieved temperatures very close to absolute zero, where quantum effects and fluctuations play a dominant role. The study shows that the energy of particles changes differently with increasing coupling strength, and the impact of dissipation models on energy is also varied.
SCIENTIFIC REPORTS
(2021)
Article
Physics, Multidisciplinary
Jakub Spiechowicz, Peter Haenggi, Jerzy Luczka
Summary: This study investigates the phenomenon of multistability in the velocity dynamics of a Brownian particle. It finds that the multistability is robust with respect to the choice of the starting position and velocity of the particle for moderate and high temperatures, but is affected by initial conditions in the low temperature regime.
Article
Mathematics, Applied
I. G. Marchenko, A. Zhiglo, V. Aksenova, V. Tkachenko, I. I. Marchenko, J. Luczka, J. Spiechowicz
Summary: We revisited the problem of diffusion in a driven system and discovered normal diffusion and intriguing giant damped quasiperiodic oscillations in the long time limit. We identified the mechanism behind this effect and suggested experimental verification.
Review
Physics, Multidisciplinary
Jakub Spiechowicz, Ivan G. Marchenko, Peter Haenggi, Jerzy Luczka
Summary: The diffusion of small particles is widely studied and applied in various scientific fields. This article focuses on the temperature dependence of the diffusion coefficient for a Brownian particle, exploring different physical systems and their diffusion characteristics.
Article
Physics, Fluids & Plasmas
I. G. Marchenko, V. Aksenova, I. I. Marchenko, J. Luczka, J. Spiechowicz
Summary: We investigate the impact of temperature on the diffusion coefficient of an inertial Brownian particle in a symmetric periodic potential under the influence of a symmetric time-periodic force. It is observed that the diffusion coefficient exhibits giant damped quasiperiodic oscillations in the low-friction regime. Our research demonstrates that the diffusion coefficient increases at its minima when temperature rises, while it decreases at the maxima within a finite temperature range. This phenomenon can be explained by considering the perturbation of deterministic dynamics by thermal fluctuations and the mean residence time of the particle in locked and running trajectories. Moreover, we show that the temperature dependence of the diffusion coefficient can be accurately reconstructed using the stationary probability distribution of the running trajectories.
Article
Physics, Fluids & Plasmas
K. Bialas, J. Luczka, J. Spiechowicz
Summary: Active fluctuations, driven by self-propulsion mechanisms or collisions with an active environment, can induce forbidden phenomena at equilibrium states. Understanding their role in living matter is a challenge for physics.
Article
Geochemistry & Geophysics
Michal P. Michalak, Leslaw Teper, Florian Wellmann, Jerzy Zaba, Krzysztof Gaidzik, Marcin Kostur, Yuriy P. Maystrenko, Paulina Leonowicz
Summary: The geological potential of sparse subsurface data is not fully exploited due to the lack of specific workflows. A new unsupervised machine learning framework is developed to cluster and analyze the spatial distribution of orientations in geological interfaces. The clustering results provide insights into potential geological structures.
Proceedings Paper
Computer Science, Artificial Intelligence
Filip Malawski, Jaroslaw Goslinski, Mikolaj Stryja, Katarzyna Jesionek, Marcin Kostur, Karol Miszalski-Jamka, Jakub Nalepa
Summary: Early diagnosis and effective monitoring of coronary artery disease are crucial for successful treatment. This study introduces an automated deep learning-powered pipeline for the analysis of coronary computed tomography angiography images, with the additional use of computational fluid dynamics to capture vessel characteristics. Experimental results show that this approach outperforms existing methods and produces blood-flow parameters strongly correlated to ground-truth delineations.
APPLICATIONS OF MEDICAL ARTIFICIAL INTELLIGENCE, AMAI 2022
(2022)
Article
Physics, Fluids & Plasmas
J. Spiechowicz, J. Luczka
Summary: This study revisited the paradigmatic model of inertial Brownian particles diffusing in a tilted periodic potential using state-of-the-art computer simulations. The results indicate that in the parameter regime where the particle velocity is bistable, an everlasting ballistic diffusion emerges when the thermal noise intensity tends to zero, resulting in the diffusion coefficient not reaching its stationary constant value.
Article
Physics, Fluids & Plasmas
J. Spiechowicz, J. Luczka
Summary: The study found that Brownian particles in a tilted periodic potential exhibit tristability in velocity dynamics, originating from the arcsine law of velocity dynamics at zero temperature. By analyzing the impact of thermal fluctuations, an efficient strategy to control multistability was proposed, which involves solely changing the force acting on the particle or the temperature of the system.
Article
Physics, Fluids & Plasmas
K. Bialas, J. Luczka, P. Haenggi, J. Spiechowicz