# 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: intermittent large-intensity pulses (LIE) due to instabilities in quasiperiodic motion (in Zeeman laser)

AA << report intermittent large-intensity pulses that originate in Zeeman laser due to instabilities in quasiperiodic motion, >>

<< one route follows torus-doubling to chaos and another goes via quasiperiodic intermittency in response to variation in system parameters. >>

<< During quasiperiodic intermittency, the temporal evolution of the laser shows intermittent chaotic bursting episodes intermediate to the quasiperiodic motion instead of periodic motion >>

<< The intermittent bursting appears as occasional large-intensity events (LIE). In particular, this quasiperiodic intermittency has not been given much attention so far from the dynamical system perspective, in general. >>

S. Leo Kingston, Arindam Mishra, Marek Balcerzak, Tomasz Kapitaniak, Syamal K. Dana. Instabilities in quasiperiodic motion lead to intermittent large-intensity events in Zeeman laser. arXiv: 2109.11847v1 [nlin.CD]. Sep 24, 2021. 

https://arxiv.org/abs/2109.11847

keywords: gst, quasiperiodic motion, intermittency, quasiperiodic intermittency, instability, chaos.

# astro: so strong concentration of 'dust pebbles' ultimately leads to a collapse

<<  'dust pebbles' are concentrated so strongly by an instability in the solar nebula that their joint gravitational force ultimately leads to a collapse >>

Comet mission reveals 'missing link' in our understanding of planet formation. Oct 25, 2017

https://m.phys.org/news/2017-10-comet-mission-reveals-link-planet.html

Jurgen Blum, Bastian Gundlach, et al. Evidence for the formation of comet 67P/Churyumov-Gerasimenko through gravitational collapse of a bound clump of pebbles. Monthly Notices of the Royal Astronomical Society, stx2741 doi: 10.1093/mnras/stx2741 Oct 25, 2017

https://academic.oup.com/mnras/article-abstract/doi/10.1093/mnras/stx2741/4564447

# 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: tipping in a low-dimensional model of a (tropical) cyclone.

 <<Tipping is the rapid, and often irreversible, change in the state of a system [Ashwin P. et al (2017)] >> 

AA << present a case study of both rate and noise-induced tipping between the stable states, relating to the destabilization or formation of a tropical cyclone. While the stochastic system exhibits transitions both to and from the non-storm state, noise-induced tipping is more likely to form a storm, whereas rate-induced tipping is more likely to be the way a storm is destabilized, and in fact, rate-induced tipping can never lead to the formation of a storm when acting alone. For rate-induced tipping acting as a destabilizer of the storm, a striking result is that both wind shear and maximal potential velocity have to increase, at a substantial rate, in order to effect tipping away from the active hurricane state. For storm formation through noise-induced tipping, (AA) identify a specific direction along which the non-storm state is most likely to get activated. >> 

Katherine Slyman, John A. Gemmer, et al. Tipping in a Low-Dimensional Model of a Tropical Cyclone. arXiv: 2307.15583v1 [math.DS]. Jul 28, 2023.

https://arxiv.org/abs/2307.15583

 

Also: vortex, instability, noise, in https://www.inkgmr.net/kwrds.html

Keywords: gst, climate, storm, cyclone, vortex, noise, tipping, noise-induced tipping

# s-gst-trade: anomalous economists: CORE

<< CORE (Curriculum Open-access Resources for Economics) ... First, it emphasizes identifying and modeling empirical regularities rather than developing mathematical models from a set of abstract, often dubious assumptions about economic behavior. Second, it focuses on fundamental issues that are connected to economics but that other texts tend to ignore – issues like financial instability, wealth creation in capitalist societies, inequality, and environmental sustainability. >>

Anomalous economists to convene at SFI. Feb. 5, 2016 2:06 p.m.

http://santafe.edu/news/item/anomalous-economists-convene-sfi/

# gst: the hypothesis of a new type of rogue waves.

<< Much attention of researchers has been paid in the recent decades to the study of rogue waves. Various mechanisms of formation of these waves were suggested. The occurrence of rogue waves is most often investigated on the basis of the mechanisms of modulation instability and superposition of waves. In both cases, an evolution of rogue waves takes place against the background of a wave field, which is reflected in the definitions of such waves. In this report, the localized waves developed in the absence of the background wave fields are considered. At the same time, their dynamics corresponds to the dynamics of rogue waves that ”appear from nowhere and disappear without a trace”. >>️

<< The waves of this type are distinguished by the fact that their dynamics occur on the zero background. This implies that rogue waves presented here are formed solely due to the nonlinear focusing. >>️

N.V. Ustinov. New type of rogue waves. arXiv:2310.17254v1 [nlin.SI]. Oct 26, 2023.  

https://arxiv.org/abs/2310.17254

Chaos, Solitons & Fractals V. 179, Feb 2024, 114467. https://www.sciencedirect.com/science/article/abs/pii/S0960077924000183

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

Keywords: gst, waves, rogue waves 

# gst: self-repelling species could self-organize.

<< Catalytically active particles form clusters when they respond not only to their own chemical targets but to those of other catalysts, too. >>️

AA  << show that the phenomenon of self-organization depends strongly on the network topology. >>️

They << modeled a three-species system (..) systems where each species responds chemotactically only to its own substrate cannot self-organize unless one species is self-attracting. >>️

<< Next, they developed a model that allowed species to respond to both their substrates and their products. Pair interactions between different species in this more complex model drove an instability that spread throughout the three-species system, causing the catalysts to clump together. Surprisingly, this self-organization process occurred even among particles that were individually self-repelling. >>️

Rachel Berkowitz. Self-Repelling Species Still Self-Organize. Physics 16, s128. Sept 19, 2023. 

https://physics.aps.org/articles/v16/s128

Vincent Ouazan-Reboul, Ramin Golestanian, Jaime Agudo-Canalejo. Network effects lead to self-organization in metabolic cycles of self-repelling catalysts. Phys. Rev. Lett. 131, 128301. Sep 19, 2023. 

http://dx.doi.org/10.1103/PhysRevLett.131.128301

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

Keywords: gst, self-assembly, network,  topology.

# life: apropos of 'dancing at a fixed point'

the last interview to Dr Albert Bourla (Pfizer) about the annual (or maybe semi-annual (?)) shot reiteration of the vaccine against #sars-cov-2   remember to me the 'homoclinic dynamics' that I cited at the 13th Meeting of the Internat Epidemiol Associat - IEA (Sydney, 1993) ... after a large trajectories started at zero point (i.e.  the fixed point), the final point of the dynamic returns at the same zero point ...

<< People will be likely to need to have annual Covid vaccinations for many years to come, the head of Pfizer [Dr Albert Bourla ] has told the BBC >>️

Fergus Walsh. Pfizer boss: Annual Covid jabs for years to come. Dec 2, 2021. 

https://www.bbc.com/news/health-59488848

Who knows if there is a convincing reason that explains why to treat a virus with a high frequency of mutations one should prefer a vaccine approach instead of an antiviral drug ...

to find: 'antiviral drugs covid-19'  

https://pubmed.ncbi.nlm.nih.gov/?term=antiviral+drugs+covid-19&filter=datesearch.y_1

Apropos of 'homoclinic orbits' ...

<< the reinjection of the departing trajectories in the vicinity of an unstable fixed point of the saddle-focus type [..] is frequently associated with the emergence of orbits of a rather exceptional type known as 'homoclinic orbits'. These are trajectories that leave the fixed point but come back to it; in other words, they tend to the same limit when time t goes to +∞ as well as to -∞ . [..]. Homoclinic orbits are very sensitive to variation of parameter [parms] values and are generally destroyed if the [parms] do not satisfy a strict equality (in the terminology of [..] they are structurally unstable). However, for nearby values of the [parms] their disappearance leaves a very rich structure of orbit in phase space, some of which behave chaotically. >>️

Nicolis G., Prigogine I. Exploring complexity. Freeman, NY (1989): 130-131.

https://www.amazon.com/Exploring-Complexity-Introduction-Gregoire-Nicolis/dp/0716718596

Apropos of: [+∞ , -∞] plus infinity, minus infinity; 

<< In modern mysticism, the infinity symbol has become identified with a variation of the ouroboros, an ancient image of a snake eating its own tail that has also come to symbolize the infinite, [..] >> 

https://en.m.wikipedia.org/wiki/Infinity_symbol

Also 

Onda omoclina. Notes. Tuesday, Jan  11, 2005 (quasi-stochastic poetry)

<< ed assistere al mutar dell' onda omoclina / (..) >>

️

https://inkpi.blogspot.com/2005/01/1639b-onda-omoclina.html

Also

Inchingolo GM.  Cultural transitions and epidemiology.  Proceedings of the 13th Scientific Meeting of the International Epidemiological Association - IEA, Sydney, Australia, Sept 26-29, 1993: 129.   Med Hypotheses 1994; 43(4): 201-206.

https://pubmed.ncbi.nlm.nih.gov/7838001/

Also

Onda di carambola. Notes. Nov  29, 2004. (quasi-stochastic poetry)

https://inkpi.blogspot.com/2004/11/1619-onda-di-carambola.html

keywords: life, dance, fixed point, homoclinic orbits, instability, chaos,  virus, coronavirus, sars-cov-2,  covid19, 2019ncov, drugs, antiviral drug, vaccine, jabs, Covid jabs.

# gst: approaching the complex mechanics of crumpled sheets

<< Crumpling an ordinary thin sheet transforms it into a structure with unusual mechanical behaviors, such as logarithmic relaxation, emission of crackling noise, and memory retention. >>️

<< the response of crumpled sheets to cyclic strain is intermittent, hysteretic, and encodes a memory of the largest applied compression. (..) these behaviours emerge due to an interplay between localized and interacting geometric instabilities in the sheet. >>

<< after training multiple memories can be encoded, a phenomenon known as return point memory. >>

AA << study lays the foundation for understanding the complex mechanics of crumpled sheets, and presents an experimental and theoretical framework for the study of memory formation in systems of interacting instabilities. >>️️

Dor Shohat, Daniel Hexner, Yoav Lahini. Memory from coupled instabilities in crumpled sheets. arXiv: 2109.05212v1 [cond-mat.soft]. Sep 11, 2021.

https://arxiv.org/abs/2109.05212

keywords: gst, sheet, crumpled sheets, instability, bistability, memory, return point memory

# pnei: pulsatile testosterone to drive pulsatile decision making during trading

<< Testosterone (..) has been shown to affect economic decision making and is taken as a performance enhancer among some financial professionals >>

Amos Nadler, Peiran Jiao, et al. The Bull of Wall Street: Experimental Analysis of Testosterone and Asset Trading. Management Science.
doi: 10.1287/mnsc.2017.2836  Sep 25, 2017.

http://pubsonline.informs.org/doi/10.1287/mnsc.2017.2836

Raging Bull: First study to find link between testosterone and stock market instability. Oct 10, 2017

https://m.phys.org/news/2017-10-raging-bull-link-testosterone-stock.html

# gst: apropos of instability, bubbles may have unexpected chills

<< Bubbles are ubiquitous, existing in everything from the foam on a beer to party toys for children. Despite this pervasiveness, there are open questions on the behavior of bubbles, such as why some bubbles are more resistant to bursting than others. >>️

AA << created a soap bubble from a mixture made of dishwashing liquid, water, and glycerol. They then measured the soap film’s temperature under a variety of environmental conditions. They found that the film could be up to 8 °C colder than the surrounding air. They also found that glycerol content of the soap film impacted this temperature difference, with films containing more glycerol having higher temperatures. Boulogne (Francois Boulogne) says that such a large temperature difference could impact bubble stability.  >>️

Anna Napolitano. Bubbles Have an Unexpected Chill. Physics 15, s173. Dec 19, 2022. 

https://physics.aps.org/articles/v15/s173

Francois Boulogne, Frederic Restagno, Emmanuelle Rio. Measurement of the Temperature Decrease in Evaporating Soap Films. Phys. Rev. Lett. 129, 268001. Dec 19, 2022.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.129.268001

Also

keyword "bubble" in FonT

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

keyword "bolla" | "bolle" in Notes (quasistochastic-poetry): 

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

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

Keywords: gst, bubble, stability, evaporation, burst