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Visualizzazione dei post in ordine di data per la query evolution. Ordina per pertinenza Mostra tutti i post
Visualizzazione dei post in ordine di data per la query evolution. Ordina per pertinenza Mostra tutti i post

giovedì 23 aprile 2026

# gst: turbulent pair dispersion with stochastic generative diffusion models.


<< ️Recent advances in data-driven modeling have shown that diffusion models can successfully generate synthetic Lagrangian trajectories in turbulent flows. Building on this progress, (AA) extend the method to the joint generation of pairs of Lagrangian velocity trajectories, enabling a fully data-driven representation of turbulent pair dispersion, a long-standing fundamental problem with broad relevance in fluid dynamics. >>

<< ️(They) demonstrate that diffusion models accurately reproduce the evolution of particle-pair separation, including deviations from Richardson's classical scaling law, while simultaneously preserving all key single-particle statistical properties reported in previous studies. These findings underscore the potential of diffusion-based generative models to emulate high-dimensional, multi-scale turbulent dynamics, further establishing them as a powerful tool for scientific modeling and for future geophysical and astrophysical applications. >>

Pantera A., Biferale L., Buzzicotti M., et al. Turbulent pair dispersion with Stochastic Generative Diffusion Models. arXiv: 2604.12932v1 [physics.flu-dyn]. Apr 14, 2026.

Also: turbulence, waves, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, turbulence, waves, diffusion models, turbulent flows, turbulent pair dispersion, stochastic generative diffusion models (DM), direct numerical simulation (DNS).

venerdì 17 aprile 2026

# gst: dispersive shock waves in periodic lattices.

<< ️(AA) introduce and systematically investigate the generation of dispersive shock waves, which arise naturally in physical settings such as optical waveguide arrays and superfluids confined within optical lattices. The underlying physically relevant model is a nonlinear Schrödinger (NLS) equation with a periodic potential. (They) consider the evolution of piecewise smooth initial data composed of two distinct nonlinear periodic eigenmodes. >>

<< ️️The resulting tight-binding approximation is shown to display higher-fidelity for deeper periodic potentials. This reduced (discrete) DNLS model effectively models the dynamics at the minima of the periodic potential of the original continuum NLS. >>

Su Yang, Sathyanarayanan Chandramouli, P. G. Kevrekidis. Dispersive shock waves in periodic lattices. arXiv: 2511.14549v3 [nlin.PS]. Apr 9,  2026.

Phys. Rev. E 113, 044204. Apr 10, 2026.


Keywords: gst, waves, dispersive shock waves.

mercoledì 8 aprile 2026

# gst: variational iterative rotation algorithm, combinatorial optimization with classical kicked tops.

<< ️(AA) investigate a classical formulation of the Quantum Approximate Optimization Algorithm (QAOA), realized as a Hamiltonian dynamical system of classical kicked tops, which (They) call the Variational Iterative Rotation Algorithm (VIRAL). The variational parameters are the transverse and longitudinal rotation angles at each of the p layers of the circuit. >>

<< ️(They) find that VIRAL outperforms QAOA on the canonical Sherrington-Kirkpatrick spin-glass benchmark at all circuit depths, with the energy density converging to the ground state value linearly in 1/p. For large circuit depths, the optimized dynamics follows a Floquet protocol in which a pitchfork bifurcation destabilizes the equatorial fixed point and drives the spins toward polar Ising configurations. >>

<< ️(Their) results demonstrate that the effectiveness of QAOA-like protocols derives primarily from their underlying iterative rotation structure, and that a classical implementation of it outperforms its quantum counterpart. (They) further elucidate its efficiency by reducing the many-body classical evolution to an effective Landau-Lifshitz dynamics for a single spin in a stochastic magnetic field. In this picture, the covariance matrix of the effective field reveals a nearly rank-one structure in which a single mode dominates the stochastic dynamics. In contrast, quantum fluctuations make the noise covariance of the effective quantum model of higher rank, hampering the control of the system. >>

Flaviano Morone, Andrew D. Kent, Dries Sels. Variational Iterative Rotation Algorithm: Combinatorial Optimization with Classical Kicked Tops. arXiv: 2604.01512v1 [cond-mat.dis-nn]. Apr 2, 2026.


Keywords: gst, kicked top, rotation, pitchfork bifurcation, quantum fluctuations. 

venerdì 3 aprile 2026

# gst: early warning signals for primary and secondary bifurcation to oscillatory instabilities.

<< ️In several natural and engineering systems, changes in control parameters can trigger bifurcations that lead to sustained or growing periodic oscillations, indicating the onset of oscillatory instabilities. Such emergent behaviour often results from positive feedback between interacting subsystems, resulting in large-amplitude oscillations that can be detrimental. >>

<< ️Several precursors are available to provide early warning of an impending oscillatory instability. In reality, practical systems may exhibit different sequences of bifurcations, including a primary bifurcation to an oscillatory state that may be either continuous or abrupt, followed by an abrupt secondary bifurcation, and further transitions beyond the secondary bifurcation. Existing precursors for oscillatory instabilities typically forewarn the onset of the primary bifurcation to an oscillatory state and tend to saturate once the system enters the oscillatory regime. Notably, primary bifurcations often involve lower amplitudes compared to the more severe states after secondary bifurcation. >>

<< ️In this study, (AA) propose a methodology based on spectral visibility graphs to get forewarning for both primary and secondary bifurcations. The method inherently captures the evolution of the harmonic content of the signal relative to other frequency components. The approach employs tuning of a single sensitivity parameter to detect different sequences of bifurcation. (They) demonstrate the usefulness of (Their) method for thermo-acoustic and aero-acoustic instabilities in multiple engineering systems involving turbulent flow and reactions. (Their) methodology can help systems prepare in advance or even avoid undesirable transitions. Tuning the sensitivity parameter allows adaptive, risk-based warnings, ensuring high performance without tipping into undesirable regimes. >>

Rohit Radhakrishnan, Prasana Kumar, Induja Pavithran, et al. Early warning signals for primary and secondary bifurcation to oscillatory instabilities. arXiv: 2603.24068v1 [physics.flu-dyn]. Mar 25, 2026.

Also: instability, turbulence, transition, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, instability, turbulence, transitions, bifurcation, feedback.

giovedì 19 febbraio 2026

# gst: elastoplastic modelling of cyclic shear deformation of amorphous solids.

IMG - Per site elastic energy evolution for poorly vs well annealed samples.

<< ️(AA) develop an energy-landscape based elasto-plastic model to understand the behaviour of amorphous solids under uniform and cyclic shear. Amorphous solids are modeled as being composed of mesoscopic sub-volumes, each of which may occupy states - termed mesostates -- drawn from a specified distribution. The energies of the mesostates under stress free conditions determine their stability range with respect to applied strain, and their plastic strain, at which they are stress free, forms an important additional property. Under applied global strain, mesostates that reach their stability limits transition to other permissible mesostates. Barring such transitions, which encompass plastic deformations that the solid may undergo, mesostates are treated as exhibiting linear elastic behavior, and the interactions between mesoscopic blocks are treated using the finite element method.  >>

<< ️The (AA) model reproduces known phenomena under uniform and cyclic shear, such as the brittle-to-ductile crossover with annealing and the Bauschinger effect for uniform shear, qualitative features of the yielding diagram under cyclic shear including the change in yielding behaviour with the degree of annealing, across a `threshold level', and dynamic phenomena such as the divergence of failure times on approach to the yield point and the non-monotonic evolution of the local yield rate.  >>

<< ️In addition to these results, (They) discuss the dependence of the observed behaviour on model choices, and open questions highlighted by (Their) work. >>

Pushkar Khandare, Srikanth Sastry. Elastoplastic Modelling of Cyclic Shear Deformation of Amorphous Solids. arXiv: 2602.06174v2 [cond-mat.soft]. Feb 5,  2026.

Also: transition, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, transitions, amorphous solids, cyclic shear, mesostates, mesoscopic sub-volumes, plastic strain, plastic deformation, linear elastic behavior, stability limits transition, brittle-to-ductile crossover, divergence of failure times.

lunedì 16 febbraio 2026

# life: the role played by women in shaping human evolution.

<< ️(AA) have used ancient DNA to reveal that hunter-gatherers in one part of Europe survived for thousands of years longer than anywhere else on the continent—and have uncovered the pivotal role of women in the process >>

<< ️Ancient DNA studies often bring to light unexpected pages of our past. We might anticipate finding the unexpected when analyzing samples from unexplored or peripheral regions of the globe. But here we are looking at the heartland of Europe, making these results even more striking. It's a testament to the power of ancient DNA studies that findings like these can still surprise us. This study has also brought to light the crucial role played by women in the transmission of knowledge from the incoming farming communities to the local hunter-gatherers. Thanks to ancient DNA studies, we can not only uncover the past but also give voice to the invaluable but often overlooked role played by women in shaping human evolution. >> Maria Pala. 

Gaby Clark, Robert Egan. Ancient DNA suggests hunter-gatherers in Europe's lowlands endured until 2500 BCE. University of Huddersfield. http://www.hud.ac.uk  Feb 11, 2026.

Olalde, I., Altena, E., Bourgeois, Q. et al. Lasting Lower Rhine–Meuse forager ancestry shaped Bell Beaker expansion. Nature (2026). https://doi.org/10.1038/s41586-026-10111-8

Also: Nomads, transition, in https://www.inkgmr.net/kwrds.html 

Keywords: Nomads, transitions, life

mercoledì 21 gennaio 2026

# gst: dynamical entanglement percolation with spatially correlated disorder.

<< ️The distribution of entanglement between the nodes of a quantum network plays a fundamental role in quantum information applications. In this work, (AA) investigate the dynamics of a network of qubits where each edge corresponds to an independent two-qubit interaction. By applying tools from percolation theory, (They) study how entanglement dynamically spreads across the network. (They) show that the interplay between unitary evolution and spatially correlated disorder leads to a non-standard percolation phenomenology, significantly richer than uniform bond percolation and featuring hysteresis. >>

Lorenzo Cirigliano, Valentina Brosco, Claudio Castellano, et al. Dynamical entanglement percolation with spatially correlated disorder. arXiv: 2601.05925v1 [quant-ph]. Jan 9, 2026.


Keywords: gst, networks, classical complex networks, quantum networks, qubit, disorder, percolation, entanglement, hysteresis.

sabato 20 dicembre 2025

# evol: fluctuating environments favor extreme dormancy strategies and penalize intermediate ones.


<< ️Dormancy is a widespread adaptive strategy that enables populations to persist in fluctuating environments, yet how its benefits depend on the temporal structure of environmental variability remains unclear. (AA) examine how dormancy interacts with environmental correlation times using a delayed-logistic model in which dormant individuals reactivate after a fixed lag while birth rates fluctuate under temporally correlated stochasticity. >> 

<< ️Numerical simulations and analytical calculations show that the combination of demographic memory and colored multiplicative noise generates a strongly non-monotonic dependence of fitness on dormancy duration, with three distinct performance regimes. Very short dormancy maximizes linear growth but amplifies fluctuations and extinction risk. Very long dormancy buffers environmental variability, greatly increasing mean extinction times despite slower growth. Strikingly, (They) find a broad band of intermediate dormancy durations that is maladaptive, simultaneously reducing both growth and persistence due to a mismatch between delay times and environmental autocorrelation. >>

<< ️An evolutionary agent-based model confirms bistability between short- and long-dormancy strategies, which avoid intermediate lag times and evolve toward stable extremes. >>

<< ️These (AA) results show that dormancy duration is not merely a life-history parameter but an adaptive mechanism tuned to environmental timescales, and that intermediate "dangerous middle" strategies can be inherently disfavored. More broadly, this work identifies a generic mechanism by which demographic delays interacting with correlated environmental variability produce a non-monotonic fitness landscape that selects for extreme timing strategies. >>

Jorge Hidalgo, Lorenzo Fant, Rafael Rubio de Casas, Miguel A. Muñoz. Fluctuating Environments Favor Extreme Dormancy Strategies and Penalize Intermediate Ones. arXiv: 2512.05856v1 [q-bio.PE]. Dec 5, 2025.

Also: evolution, transition, disorder & fluctuations, noise, in https://www.inkgmr.net/kwrds.html 

Keywords: evolution, adaptation, transition, dormancy, fluctuating environments, stochasticity, noise.

venerdì 19 dicembre 2025

# gst: bursting bubbles in Herschel-Bulkley fluids, dynamics and jetting transitions.


<< ️When a bubble rises to a free surface, its bursting dynamics in Newtonian fluids are governed by the interplay between viscous, capillary, and gravitational forces. In this work, (AA) extend this classical problem to Herschel-Bulkley fluids, elucidating the role of viscoplasticity and non-Newtonian rheology in bubble bursting. Using direct numerical simulations validated against experiments, (They) systematically explore the influence of the key governing dimensionless parameters, such as the Bond number, the Ohnesorge number, the shear-dependent behavior and the plastocapillary number, each varied over several orders of magnitude. >>

<< ️(AA) results reveal that viscoplasticity strongly controls the evolution and interaction of capillary waves within the cavity formed upon bubble rupture. Shear-thinning and shear-thickening effects are significant only for moderate Ohnesorge numbers, while at large Ohnesorge values the free surface dynamics converge to a non-flat equilibrium shape once the internal stresses fall below the yield stress. >>

<< ️These (AA) findings provide new insights into the coupled effects of viscosity, gravity, yield stress, and shear-dependent rheology in multiphase flows, with broad implications for natural and industrial processes involving gas-liquid interfaces. >>

A. H. Ghaemi, Z. Yang, A. Huang, et al. Bursting bubbles in Herschel-Bulkley fluids: dynamics and jetting transitions. arXiv: 2511.23345v1 [physics.flu-dyn]. Nov 28, 2025.

Also: bubble, waves, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, bubble, waves, capillary waves, bubble bursting, bubble rupture, viscosity, capillary and gravitational forces, shear-thinning and shear-thickening effects, yield stress, free surface dynamics, non-flat equilibrium.

domenica 30 novembre 2025

# gst: apropos of Parrondo paradox, controlling quantum chaos via Parrondo strategies on noisy intermediate-scale quantum hardware


<< ️Advancements in noisy intermediate-scale quantum (NISQ) computing are steadily pushing these systems toward outperforming classical supercomputers on specific well-defined computational tasks. In this work (AA) explore and control quantum chaos in NISQ systems using discrete-time quantum walks (DTQWs) on cyclic graphs. To efficiently implement quantum walks on NISQ hardware, (They) employ the quantum Fourier transform to diagonalize the conditional shift operator, optimizing circuit depth and fidelity. >>

<< ️(AA) experimentally realize the transition from quantum chaos to order via DTQW dynamics on both odd and even cyclic graphs, specifically 3- and 4-cycle graphs, using the counterintuitive Parrondo paradox strategy across three different NISQ devices. >>

<< ️While the 4-cycle graphs exhibit high-fidelity quantum evolution, the 3-cycle implementation shows significant fidelity improvement when augmented with dynamical decoupling pulses. (Their) results demonstrate a practical approach to probing and harnessing controlled chaotic dynamics on real quantum hardware, laying the groundwork for future quantum algorithms and cryptographic protocols based on quantum walks. >>

Aditi Rath, Dinesh Kumar Panda, Colin Benjamin. Controlling quantum chaos via Parrondo strategies on noisy intermediate-scale quantum hardware. Phys. Rev. E 112, 054219. Nov 18, 2025.

arXiv: 2506.11225v2 [quant-ph]. Nov 4, 2025.

Also: parrondo, noise, walk, walking, order, chaos, transition, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, parrondo, noise, walk, walking, quantum walk, order, chaos, quantum chaos, transition, dynamical decoupling pulses, cryptography.

martedì 16 settembre 2025

# gst: randomness with constraints: constructing minimal models for high-dimensional biology.


<< ️Biologists and physicists have a rich tradition of modeling living systems with simple models composed of a few interacting components. Despite the remarkable success of this approach, it remains unclear how to use such finely tuned models to study complex biological systems composed of numerous heterogeneous, interacting components. >>

<< ️One possible strategy for taming this biological complexity is to embrace the idea that many biological behaviors we observe are ``typical'' and can be modeled using random systems that respect biologically-motivated constraints. Here, (AA) review recent works showing how this approach can be used to make close connection with experiments in biological systems ranging from neuroscience to ecology and evolution and beyond. Collectively, these works suggest that the ``random-with-constraints'' paradigm represents a promising new modeling strategy for capturing experimentally observed dynamical and statistical features in high-dimensional biological data and provides a powerful minimal modeling philosophy for biology. >>

Ilya Nemenman, Pankaj Mehta. Randomness with constraints: constructing minimal models for high-dimensional biology. arXiv: 2509.03765v1 [physics.bio-ph]. Sep 3, 2025.

Also: random, transition, disorder & fluctuations, fly at random, quasi-stochastic poetry, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, randomness, transitions, disorder & fluctuations, random-with-constraints, fly at random, quasi-stochastic poetry.

venerdì 12 settembre 2025

# gst: shock waves in classical dust collapse.

<< ️During gravitational collapse of dust in spherical symmetry, matter particles may collide forming shell crossing singularities (SCSs) at which the Einstein equations become indeterminate. >>

<< ️(AA) show that in the case of marginally bound dust collapse, there is a unique evolution beyond SCSs such that a propagating shock wave forms, the metric remains continuous, and the stress-energy tensor dynamically becomes that of a thin shell. (They) give numerical simulations that exhibit this result. >>

Viqar Husain, Hassan Mehmood. Shock waves in classical dust collapse. Phys. Rev. Research 7, 033215. Sep 3, 2025.

arXiv: 2504.14883v1 [gr-qc]. Apr 21, 2025.

Also: particle, singularity, collapse, waves, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, particles, singularity, shell crossing singularities, waves, shock waves, gravitational waves, collapse, dust collapse, gravitational collapse. 

venerdì 18 luglio 2025

# gst: self-feedback delay induces extreme events in the theoretical Brusselator system.

AA << ️present a study of the theoretical Brusselator model with time-delayed self-feedback, demonstrating its ability to induce extreme events when delays in reaction processes significantly influence subsequent dynamics, with and without diffusion. >>

<< ️Stability analyses reveal the mechanisms driving this behavior with respect to the delay time. The occurrence of extreme events is validated using various numerical and statistical tools, including phase portraits, time series, probability distribution functions, return periods, and spatiotemporal evolution. >>

<< ️A comprehensive two-parameter scan delineates the parameter regimes where the extreme events emerge, alongside the identification of transient chaos within specific regions of the parameter space. To confirm these numerical findings, (AA) constructed an analog electronic circuit that emulates the model, providing experimental validation of the predicted dynamics. >>

S. V. Manivelan, S. Sabarathinam, et al. Self-feedback delay induces extreme events in the theoretical Brusselator system. Phys. Rev. E 112, 014202. Jul 1, 2025.

Also: chaos, transition, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, Brusselator system, self-feedback, delay, chaos, transient chaos, transitions, extreme events.

giovedì 17 luglio 2025

# gst: prethermalization in Fermi-Pasta-Ulam-Tsingou chains

<< ️The observation of the Fermi-Pasta-Ulam-Tsingou (FPUT) paradox, namely the lack of equipartition in the evolution of a normal mode in a nonlinear chain on unexpectedly long times, is arguably the most famous numerical experiment in the history of physics. >> 

<< ️Seventy years after the original publication, most studies in FPUT chains still focus on long wavelength initial states similar to the original paper. It is shown here that all characteristic features of the FPUT paradox are rendered even more striking if modes with short(er) wavelengths are evolved instead. >>

<< ️Since not every normal mode leads to equipartition, (AA) also provide a simple technique to predict which modes, and in what perturbation order, are excited starting from an initial mode (root) in 𝛼-FPUT chains. The excitation sequences associated with a root are then numerically shown to spread energy at different speeds, leading to prethermalization regimes that become longer as a function of mode excitation number. This effect is visible in observables such as mode energies and spectral entropies and, surprisingly, also in the time evolution of invariant quantities such as Lyapunov times and Kolmogorov-Sinai entropies. >>

AA << findings generalize the original FPUT experiment, provide an original look at the paradox's source, and enrich the vast literature dedicated to studying equipartition in classical many-body systems. >>

Gabriel M. Lando, Sergej Flach. Prethermalization in Fermi-Pasta-Ulam-Tsingou chains. Phys. Rev. E 112, 014206. Jul 8, 2025.

arXiv:2504.04725v2 [cond-mat.stat-mech]. Jul 9, 2025.

Also: Fermi– Pasta– Ulam– Tsingou problem. Wikipedia, Jun 16, 2025. 
https://en.m.wikipedia.org/


Keywords: gst, paradox, FPUT.

venerdì 11 luglio 2025

# gst: wave-kinetic dynamics of forced-dissipated turbulent internal gravity waves

<< Internal gravity waves are an essential feature of stratified media, such as oceans and atmospheres. >>

<< To investigate their dynamics, (AA) perform simulations of the forced-dissipated kinetic equation describing the evolution of the energy spectrum of weakly nonlinear internal gravity waves. >>

<< During the early evolution, three well-known nonlocal interactions, the elastic scattering, the induced diffusion, and the parametric subharmonic instability, together with a superharmonic resonance play a prominent role. >>

<< In contrast, local interactions are responsible for anisotropic energy cascade on longer timescales. >>

AA << reveal emergence of a condensate at small horizontal wave vectors that can be interpreted as a pure wave-wave interaction-mediated layering process. >>

Vincent Labarre, Giorgio Krstulovic, Sergey Nazarenko. Wave-Kinetic Dynamics of Forced-Dissipated Turbulent Internal Gravity Waves. Phys. Rev. Lett. 135, 014101. Jul 1, 2025.

arXiv:2407.11469v3 [physics.flu-dyn]. Mar 28, 2025.

Also: waves, weak, turbulence, transition, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, waves, weakness, turbulence, transitions, stratified turbulence, wave-turbulence interactions, weak turbulence.

sabato 5 luglio 2025

# gst: transient and steady-state chaos in dissipative quantum systems.


<< Dissipative quantum chaos plays a central role in the characterization and control of information scrambling, non-unitary evolution, and thermalization, but it still lacks a precise definition. >>

AA << properly restore the quantum-classical correspondence through a dynamical approach based on entanglement entropy and out-of-time-order correlators (OTOCs), which reveal signatures of chaos beyond spectral statistics. Focusing on the open anisotropic Dicke model, (They) identify two distinct regimes: transient chaos, marked by rapid early-time growth of entanglement and OTOCs followed by low saturation values, and steady-state chaos, characterized by high long-time values. >>

AA << introduce a random matrix toy model and show that Ginibre spectral statistics signals short-time chaos rather than steady-state chaos. (Their) results establish entanglement dynamics and OTOCs as reliable diagnostics of dissipative quantum chaos across different timescales. >>

Debabrata Mondal, Lea F. Santos, S. Sinha. Transient and steady-state chaos in dissipative quantum systems. arXiv: 2506.05475v1 [quant-ph]. Jun 5, 2025. 

Also: chaos, transition, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, information scrambling, entropy, chaos, transient chaos, steady-state chaos.

martedì 1 luglio 2025

# game: Parrondo's paradox in space-inhomogeneous quantum walks.

<< The term Parrondo's paradox refers to the apparently paradoxical effect whereby two or more dynamics in which a given quantity decreases are combined in such a way that the same quantity increases in the resulting dynamics. >>

AA << show that Parrondo's paradox can occur not only in the case of homogeneous but also in space-inhomogeneous one-dimensional discrete-time quantum walks. >>

<< Moreover, (They) demonstrate that for such quantum walks Parrondo's paradox can affect the time evolution of quantum entanglement differently than it does in the case of homogeneous ones. >>

Zbigniew Walczak, Jarosław H. Bauer. Parrondo's paradox in space-inhomogeneous quantum walks. Phys. Rev. E 111, 064218. Jun 25, 2025.

Also: Parrondo, game, in https://www.inkgmr.net/kwrds.html 

Keywords: Parrondo, games

lunedì 30 giugno 2025

# gst: topological phase transition under infinite randomness

<< In clean and weakly disordered systems, topological and trivial phases having a finite bulk energy gap can transit to each other via a quantum critical point. In presence of strong disorder, both the nature of the phases and the associated criticality can fundamentally change. >>

Here AA << investigate topological properties of a strongly disordered fermionic chain where the bond couplings are drawn from normal probability distributions which are defined by characteristic standard deviations. Using numerical strong disorder renormalization group methods along with analytical techniques, (AA) show that the competition between fluctuation scales renders both the trivial and topological phases gapless with Griffiths like rare regions. >>

<< Moreover, the transition between these phases is solely governed by the fluctuation scales, rather than the means, rendering the critical behavior to be determined by an infinite randomness fixed point with an irrational central charge. (AA) work points to a host of novel topological phases and atypical topological phase transitions which can be realized in systems under strong disorder. >>

Saikat Mondal, Adhip Agarwala. Topological Phase Transition under Infinite Randomness. arXiv: 2506.19913v1 [cond-mat.dis-nn]. Jun 24, 2025.

Also: order, disorder, disorder & fluctuations, random, transition, forms of power, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, order, disorder, disorder & fluctuations, randomness, criticality, transitions, forms of power

FonT: who knows if during some master's courses on the organization and evolution of social enclosures, held by the legendary "Frattocchie School" ( https://it.m.wikipedia.org/wiki/Scuola_delle_Frattocchie ) during the early 80s (but also early 90s) some bizarre theoretician advanced the imaginative, up in the air, absolutely unfounded hypothesis (here it is emphasized: absolutely), about the possibility of an immediate cracking of a social structure due to the action of idiots (?) disguised as idiots until the complete, universal, ontheback breakthrough anzicheforse?

martedì 24 giugno 2025

# gst: far-from-equilibrium complex landscapes


<< Systems with a complex dynamics like glasses or models of biological evolution are often pictured in terms of a complex landscape, with a large number of possible collective states. (AA) show on the example of a stochastic spin model with nonreciprocal and heterogeneous interactions how the complex landscape picture can be generalized far from equilibrium, where collective states may become time-dependent and exhibit, e.g., spontaneous oscillations, often hidden by the presence of disorder. >>

AA << identify relevant observables, like the density of entropy production rate, to unveil the spontaneous collective time dependence, and  determine a configurational entropy which counts the number of oscillating collective states when this number grows exponentially with system size. >>

Laura Guislain, Eric Bertin. Far-from-equilibrium complex landscapes. Phys. Rev. E 111, L062101 Jun 16, 2025.

arXiv: 2405.08452v1 [cond-mat.dis-nn]. May 14, 2024.

Also: evolution, order, disorder, disorder & fluctuations, chaos, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, evolution, complexity, entropy, configurational entropy, order, disorder, disorder & fluctuations, spontaneous oscillations, chaos.

venerdì 13 giugno 2025

# gst: self-organization to multicriticality; when a system can self-organize to a new type of phase transition while staying on the verge of another.

<< Self-organized criticality is a well-established phenomenon, where a system dynamically tunes its structure to operate on the verge of a phase transition. Here, (AA) show that the dynamics inside the self-organized critical state are fundamentally far more versatile than previously recognized, to the extent that a system can self-organize to a new type of phase transition while staying on the verge of another. >>

<< In this first demonstration of self-organization to multicriticality, (AA) investigate a model of coupled oscillators on a random network, where the network topology evolves in response to the oscillator dynamics. (They) 
 show that the system first self-organizes to the onset of oscillations, after which it drifts to the onset of pattern formation while still remaining at the onset of oscillations, thus becoming critical in two different ways at once. >>
 
<< The observed evolution to multicriticality is robust generic behavior that (AA) expect to be widespread in self-organizing systems. Overall, these results offer a unifying framework for studying systems, such as the brain, where multiple phase transitions may be relevant for proper functioning.>>

Silja Sormunen, Thilo Gross, Jari Saramäki. Self-organization to multicriticality. arXiv: 2506.04275v1 [nlin.AO]. Jun 4, 2025. 

Also: network, random, self-assembly, transition, brain, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, network, random, self-assembly, transition, phase transition, multiple phase transitions, self-organizing systems, self-organized criticality, multicriticality, brain.