# gst: multiple Pareto-optimal solutions of the dissipation-adaptation trade-off

<< Adaptation refers to the ability to recover and maintain “normal” function on perturbations of internal or external conditions and is essential for sustaining life. Biological adaptation mechanisms are dissipative, i.e., they require a supply of energy such as the coupling to the hydrolysis of ATP. Via evolution the underlying biochemical machinery of living organisms evolved into highly optimized states. However, in the case of adaptation processes two quantities are optimized simultaneously, the adaptation speed or accuracy and the thermodynamic cost. In such cases one typically faces a trade-off, where improving one quantity implies worsening the other. The solution is no longer unique but rather a Pareto set—the set of all physically attainable protocols along which no quantity can be improved without worsening another. >> 

AA << investigate Pareto fronts in adaptation-dissipation trade-offs for a cellular thermostat and a minimal ATP-driven receptor-ligand reaction network. (They) find convex sections of Pareto fronts to be interrupted by concave regions, implying the coexistence of distinct optimization mechanisms. (They) discuss the implications of such “compromise-optimal” solutions and argue that they may endow biological systems with a superior flexibility to evolve, resist, and adapt to different environments. >>️

Jorge Tabanera-Bravo, Aljaz Godec. Multiple Pareto-optimal solutions of the dissipation-adaptation trade-off. 

Phys. Rev. Research 7, 013020. Jan 7, 2025.

https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearch.7.013020

Also: 'dissipation' in FonT  https://flashontrack.blogspot.com/search?q=dissipation

Also: 'adaptation' in FonT  https://flashontrack.blogspot.com/search?q=adaptation   in Notes (quasi-stochastic poetry) (a) https://inkpi.blogspot.com/search?q=adaptation   

(b) https://inkpi.blogspot.com/search?q=adattamento

Keywords: gst, adaptation, dissipation

# gst: tuning to the edge of instability (in the cochlea)

<< Sound produces surface waves along the cochlea's basilar membrane. To achieve the ear's astonishing frequency resolution and sensitivity to faint sounds, dissipation in the cochlea must be canceled via active processes in hair cells, effectively bringing the cochlea to the edge of instability. But how can the cochlea be globally tuned to the edge of instability with only local feedback? >>

<< Surprisingly, (AA) find the basilar membrane supports two qualitatively distinct sets of modes: a continuum of localized modes and a small number of collective extended modes. Localized modes sharply peak at their resonant position and are largely uncoupled. As a result, they can be amplified almost independently from each other by local hair cells via feedback reminiscent of self-organized criticality. >>

<< However, this amplification can destabilize the collective extended modes; avoiding such instabilities places limits on possible molecular mechanisms for active feedback in hair cells. >>

AA << work illuminates how and under what conditions individual hair cells can collectively create a critical cochlea. >>️

Asheesh S. Momi, Michael C. Abbott, et al. Hair Cells in the Cochlea Must Tune Resonant Modes to the Edge of Instability without Destabilizing Collective Modes. PRX Life 3, 013001. Jan 2, 2025.

https://journals.aps.org/prxlife/abstract/10.1103/PRXLife.3.013001 

Also: sound, music, pause, silence, instability, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, acoustics, bifurcations, sensory processes, sound detection, auditory system, ear, criticality, self-organized criticality, sound, music, pause, silence, instability

# gst: apropos of viscoelastic flow instabilities, uncertainty in elastic turbulence.

<< Elastic turbulence can lead to increased flow resistance, mixing and heat transfer. Its control - either suppression or promotion - has significant potential, and there is a concerted ongoing effort by the community to improve our understanding. >>

AA << identify four regimes of uncertainty evolution, characterised by I) rapid transfer to large scales, with large scale growth rates of τ6 (where τ represents time), II) a dissipative reduction of uncertainty, III) exponential growth at all scales, and IV) saturation. These regimes are governed by the interplay between advective and polymeric contributions (which tend to amplify uncertainty), viscous, relaxation and dissipation effects (which reduce uncertainty), and inertial contributions. >>

<< In elastic turbulence, reducing Reynolds number increases uncertainty at short times, but does not significantly influence the growth of uncertainty at later times. At late times, the growth of uncertainty increases with Weissenberg number, with decreasing polymeric diffusivity, and with the logarithm of the maximum length scale, as large flow features adjust the balance of advective and relaxation effects. >>

Jack R. C. King, Robert J. Poole, et al. Uncertainty in Elastic Turbulence. arXiv: 2501.09421v1 [physics.flu-dyn]. Jan 16, 2025. 

https://arxiv.org/abs/2501.09421

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

Keywords: gst, uncertainty, elastic, elasticity, turbulence 

# gst: trade-off between coherence and dissipation for excitable phase oscillators.

<< Thermodynamic uncertainty relation (TUR) bounds coherence in stochastic oscillatory systems. In this paper, (AA) show that both dynamical and thermodynamic bounds play important roles for the excitable oscillators, e.g. neurons. >>

<< Excitable systems such as neurons have distinctive coherence features compared with other oscillators having no excitability. >>️

AA << combined the well-established results, i.e. the fluctuation of the ISI (inter-spike-interval) limited by 1/3 and the coherence resonance phenomenon, together with the TUR developed in recent years to investigate the coherence in the excitable phase oscillators. (AA) find quite different trade-off relation in the subthreshold (excitable) region and superthreshold (oscillatory) region, separated by the SNIC (saddle-node on an invariant circle) bound but meanwhile lower bounded by the TUR. Furthermore, (They) found that there is an optimal entropy production corresponding to the maximum coherence, which could serve as an alternative interpretation of the coherence resonance. It implies that more entropy production does not necessarily result in higher accuracy of currents. >>️

Chunming Zheng. Trade-off between coherence and dissipation for excitable phase oscillators. arXiv: 2412.16603v1 [cond-mat.stat-mech]. Dec 21, 2024.

https://arxiv.org/abs/2412.16603

Also: brain, entropy, dissipation, uncertainty, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, brain, neurons, entropy, oscillators, excitable phase oscillators, coherence, dissipation, uncertainty

# gst: dynamics of small droplets in turbulent multiphase flows

AA << show unambiguously that the formation of small droplets is governed by the internal dynamics which occurs during the breakup of large drops and that the high vorticity and the extreme dissipation associated to these events are the consequence and not the cause of the breakup. >>️

M. Crialesi-Esposito, G. Boffetta, L. Brandt, et al. How small droplets form in turbulent multiphase flows. Phys. Rev. Fluids 9, L072301. Jul 29, 2024. 

https://journals.aps.org/prfluids/abstract/10.1103/PhysRevFluids.9.L072301

Also: drop, bubble, transition, turbulence, intermittency, in https://www.inkgmr.net/kwrds.html 

Keywords: gst, drop, droplet, droploid,  bubble, transition, turbulence, intermittency

# gst: to find a separation between plunging and spilling wave breakers

<< While understanding breaking waves is crucial for the development of parametrizations used in ocean wave modeling for both deep and shallow water, the complete process of wave breaking is not well understood. Here (AA) present direct numerical simulations of two-dimensional solitary waves that shoal and break on a uniform beach in shallow water, with the presence of storm surge represented by an inshore region. >>️

They << classify wave breaker types and find a separation between plunging and spilling breakers when scaled by breaking amplitude and depth. (AA) compare energy dissipation during the breaking process with results from the literature without storm surge.  >>️

They << conclude that a previously developed shallow-water inertial dissipation model for wave breaking on a uniform slope can be extended to this storm surge environment with good data collapse, and further discuss possibilities for a general parametrization of wave breaking valid across different depth regimes. >>️

Hunter Boswell, Guirong Yan, Wouter Mostert. Characterizing energy dissipation of shallow-water wave breaking in a storm surge. Phys. Rev. Fluids 8, 054801. May 5, 2023. 

https://journals.aps.org/prfluids/abstract/10.1103/PhysRevFluids.8.054801

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

Keywords: gst, waves, soliton, drop 

# gst: pattern generation through turbulent cascades

<< Fully developed turbulence is a universal and scale-invariant chaotic state characterized by an energy cascade from large to small scales where the cascade is eventually arrested by dissipation. In this Letter, (AA) show how to harness these seemingly structureless turbulent cascades to generate patterns. Conceptually, pattern or structure formation entails a process of wavelength selection: patterns typically arise from the linear instability of a homogeneous state. By contrast, the mechanism (they) propose here is fully non-linear and triggered by a non-dissipative arrest of turbulent cascades. Instead of being dissipated, energy piles up at intermediate scales. Using a combination of theory and large-scale simulations, (AA) show that the tunable wavelength of these cascade-induced patterns is set by a non-dissipative transport coefficient called odd or gyro viscosity. This non-dissipative viscosity is ubiquitous in chiral systems (..). Beyond chiral fluids, cascade-induced pattern formation could occur in natural systems (..) as well as in industrial processes (..). >>

Xander M. de Wit, Michel Fruchart, et al. Pattern formation by non-dissipative arrest of turbulent cascades. arXiv: 2304.10444v1 [cond-mat.soft]. Apr 20, 2023.

https://arxiv.org/abs/2304.10444

Also: 'turbulence', 'vortex', 'game', 'evolution', 'ai' in https://www.inkgmr.net/kwrds.html

Keywords: gst, vortex, vorticity,  turbulence, turbulent cascade, pattern formation, game, evolution, ai (artificial intelligence)

# gst: when science meets poetry, an image of three-dimensional stepped cracks (bistability, and their transition to simple cracks)

<< Slow cracks may be simple, with no internal structure. The leading edge of a simple crack, the crack front, forms a single fracture plane in its wake. Slow cracks may also develop segmented crack fronts, each segment propagating along a separate fracture plane. These planes merge at locations that form steps along fracture surfaces. Steps are not stationary, but instead propagate within a crack front. Real-time measurements of crack front structure and energy flux reveal that step dynamics significantly increase energy dissipation and drastically alter crack dynamics. Simple and stepped cracks are each stable. By extending the use of energy balance to include 3D crack front structure, (AA) find that, while energy balance is obeyed, it is insufficient to select the energetically favorable crack growth mode. Transitions from stepped cracks to simple cracks occur only when their in-plane front lengths become equal and a perturbation momentarily changes step topology. Such 3D crack dynamics challenge our traditional understanding of fracture. >>

Meng Wang, Mokhtar Adda-Bedia, Jay Fineberg. Dynamics of three-dimensional stepped cracks, bistability, and their transition to simple cracks. Phys. Rev. Research 5, L012001. Jan 9, 2023. 

https://journals.aps.org/prresearch/abstract/10.1103/PhysRevResearch.5.L012001

Also

keyword 'crack' in FonT

https://flashontrack.blogspot.com/search?q=crack

keyword 'rottura' | 'crepa' | 'frattura' | 'rugosa' in Notes

(quasi-stochastic poetry)

https://inkpi.blogspot.com/search?q=rottura

https://inkpi.blogspot.com/search?q=crepa

https://inkpi.blogspot.com/search?q=frattura

https://inkpi.blogspot.com/search?q=rugosa

keywords 'meets poetry' in FonT

https://flashontrack.blogspot.com/search?q=meets+poetry

Keywords:  gst, transitions, dynamical phase transitions, crack, cracking,   fracture, roughness

# gst: transitions, how two saddles can increase the transient times.

FIG. 8. Attractor and chaotic saddles (..) amplified around three bands of the chaotic attractor.  The global chaotic saddle is colored blue, and the local chaotic saddle is colored red. The attractors are colored black. 

AA << consider a dissipative version of the standard nontwist map. Nontwist systems present a robust transport barrier, called the shearless curve, that becomes the shearless attractor when dissipation is introduced. This attractor can be regular or chaotic depending on the control parameters. Chaotic attractors can undergo sudden and qualitative changes as a parameter is varied. These changes are called crises, and at an interior crisis the attractor suddenly expands. Chaotic saddles are nonattracting chaotic sets that play a fundamental role in the dynamics of nonlinear systems, they are responsible for chaotic transients, fractal basin boundaries, chaotic scattering and they mediate interior crises. >>

<< In this work (AA) discuss the creation of chaotic saddles in a dissipative nontwist system and the interior crises they generate. (They) show how the presence of two saddles increase the transient times and analyze the phenomenon of crisis induced intermittency. >>️

Rodrigo Simile Baroni, Ricardo Egydio de Carvalho, et al. Chaotic saddles and interior crises in a dissipative nontwist system. arXiv: 2211.06921v1 [nlin.CD]. Nov 13, 2022. 

https://arxiv.org/abs/2211.06921

Also

keyword 'intermittency' in FonT

https://flashontrack.blogspot.com/search?q=intermittency

keyword 'dissipation' in FonT

https://flashontrack.blogspot.com/search?q=dissipation

keyword 'saddle' in FonT

https://flashontrack.blogspot.com/search?q=saddle

keyword 'chaos' | 'chaotic' in Font

https://flashontrack.blogspot.com/search?q=chaos

https://flashontrack.blogspot.com/search?q=chaotic

keyword 'caos' | 'caotico' in Notes (quasi-stochastic poetry)

https://inkpi.blogspot.com/search?q=caos

https://inkpi.blogspot.com/search?q=caotico

Keywords: gst, transitions, dissipation, 

dissipative systems, chaos, saddle, chaotic saddle, crisis, interior crisis, intermittency

# gst: a concrete image, chirality by dissipation, 'this effect actually owes its existence to dissipation'

<< Normally, dissipation alters or weakens existing quantum effects-but here we have an effect that actually owes its existence to dissipation, >>  Tilman Esslinger

<< "No scientist thinks in formulae," Albert Einstein allegedly once told his colleague Leopold Infeld. In fact, especially for physicists, who deal with such abstract things as quantum physics, it is often immensely useful to work with concrete images rather than mathematical symbols. >>

Oliver Morsch. Unexpected twist in a quantum system. ETH Zurich.  Jan 10, 2020.

https://m.phys.org/news/2020-01-unexpected-quantum.html

Nishant Dogra, Manuele Landini, et al.  Dissipation-induced structural instability and chiral dynamics in a quantum gas.  Science  20 Dec 2019:

Vol. 366, Issue 6472, pp. 1496-1499

DOI: 10.1126/science.aaw4465

https://science.sciencemag.org/content/366/6472/1496   

# gst: the transition from quiescent spherical cap states to self-piloted motile states of volatile droplets

<< When a volatile solvent droplet is deposited on a freely floating swellable sheet, it can spontaneously become lobed, asymmetric, and either spin, slide or move via a combination of the two. This process of symmetry-breaking is a consequence of the solvent droplet swelling the membrane and its inhomogeneous evaporation from the membrane, coupled with the hydrodynamics within the droplet. By tuning the membrane thickness and the droplet size, (AA) find a critical threshold that determines the transition from a quiescent spherical cap state to a self-piloted motile state. Simple scaling laws determine the angular and linear velocities of the droplets, and a 1D analog experiment confirms the relative roles of evaporation, swelling and viscoelastic dissipation.  >>

Aditi Chakrabarti, Gary P. T. Choi, L. Mahadevan. Spontaneous spin-sliding of volatile drops on swelling sheets. 

arXiv:1910.07064v1 [cond-mat.soft]. Oct 15, 2019

https://arxiv.org/abs/1910.07064   

Also

keyword 'droplet' in FonT  

https://flashontrack.blogspot.com/search?q=droplet

# phys: a base-level fuzziness; black holes and strange metals go to extremes in some common way

<< black holes and strange metals go to extremes in some common way (..)  electrons inside a variety of ceramic crystals called "cuprates" seem to dissipate energy as quickly as possible, apparently bumping up against a fundamental quantum speed limit. >>

<<  ħ is the quantum unit of uncertainty:  an inescapable, base-level fuzziness in nature >>

Natalie Wolchover. Universal Quantum Phenomenon Found in Strange Metals.   Nov 19, 2018.

https://www.quantamagazine.org/universal-quantum-phenomenon-found-in-superconductors-20181119/

https://twitter.com/QuantaMagazine/status/1104730889500745731

A. Legros, S. Benhabib, et al. Universal T-linear resistivity and Planckian dissipation in overdoped cuprates. Nature Physics. volume 15, pages 142–147 (2019).

https://www.nature.com/articles/s41567-018-0334-2