# gst: random walk model for dual cascades in wave turbulence.

<< Dual cascades in turbulent systems with two conserved quadratic quantities famously arise in both two-dimensional hydrodynamic turbulence and also in wave turbulence based on four-wave interactions. >>

<< in wave turbulence the systematic spectral fluxes observed in a dual cascade do not require an irreversible dynamical mechanism, rather, they arise as the inevitable outcome of blind chance. >>️️

Oliver Bühler. Random walk model for dual cascades in wave turbulence. Phys. Rev. E 109, 055102. May 1, 2024. 

https://journals.aps.org/pre/abstract/10.1103/PhysRevE.109.055102

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

Keywords: gst, waves, turbulence, weak turbulence, random, random walks

# gst: apropos of random walks, intermittent random walks under stochastic resetting

AA << analyze a one-dimensional intermittent random walk on an unbounded domain in the presence of stochastic resetting. In this process, the walker alternates between local intensive search, diffusion, and rapid ballistic relocations in which it does not react to the target. >>

AA << demonstrate that Poissonian resetting leads to the existence of a non-equilibrium steady state. (They) calculate the distribution of the first arrival time to a target along with its mean and show the existence of an optimal reset rate. In particular, (..) the initial condition of the walker, i.e., either starting diffusely or relocating, can significantly affect the long-time properties of the search process. >>

<< the presence of distinct parameter regimes for the global optimization of the mean first arrival time when ballistic and diffusive movements are in direct competition. >>️

Rosa Flaquer-Galmes, Daniel Campos,  Vicenc Mendez. Intermittent random walks under stochastic resetting. Phys. Rev. E 109, 034103. March 4, 2024. 

https://journals.aps.org/pre/abstract/10.1103/PhysRevE.109.034103  

Also: walk, walking, random, in https://www.inkgmr.net/kwrds.html

Keywords: gst, walk, intermittent random walk, stochasticity, stochastic resetting

gst: actually and counterintuitively a coherent jump could generate disorder.

AA << consider a quantized version of a model for “random walk in random environment.” (..) For a ring geometry (a chain with periodic boundary condition) it features a delocalization-transition as the bias in increased beyond a critical value, indicating that the relaxation becomes underdamped. Counterintuitively, the effective disorder is enhanced due to coherent hopping. >>

Ben Avnit, Doron Cohen. Quantum walk in stochastic environment. Phys. Rev. E 108, 054111. Nov 7, 2023. 

https://journals.aps.org/pre/abstract/10.1103/PhysRevE.108.054111

Also:  Voli a casaccio. Notes (quasi-stochastic poetry). Oct 01, 2006.

https://inkpi.blogspot.com/2006/10/2066-voli-casaccio.html

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

Keywords: gst, walk, random walk, quantum walk, qu-walk, jump, transition, disorder, chaos

# game: noise-induced Parrondo's paradox in discrete-time qu-walks

<< 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 noise can induce Parrondo's paradox in one-dimensional discrete-time quantum walks with deterministic periodic as well as aperiodic sequences of two-state quantum coins where this paradox does not occur in the absence of noise. >>️

Zbigniew Walczak, Jarosław H. Bauer. Noise-induced Parrondo's paradox in discrete-time quantum walks. Phys. Rev. E 108, 044212. Oct 11, 2023.

https://journals.aps.org/pre/abstract/10.1103/PhysRevE.108.044212

Also: parrondo, walk, noise, in: https://www.inkgmr.net/kwrds.html

Keywords: games, parrondo, walk, noise

# gst: rich behaviors from stochastic walking with variable long jumps.

AA << propose a generalized model where the random walker takes stochastic jumps of lengths proportional to its present position with certain probability, otherwise it makes forward and backward jumps of fixed (unit) length with given rates. The model exhibits a rich stochastic dynamic behavior.  (AA) obtain exact analytic results for the first two moments of the walker's displacement and show that a phase transition from a diffusive to superdiffusive regime occurs if the stochastic jumps of lengths that are twice (or more) of its present positions are allowed. This phase transition is accompanied by a reentrant diffusive behavior. >> 

Upendra Harbola. Stochastic walker with variable long jumps. Phys. Rev. E 108, 014135. July 28, 2023. 

https://journals.aps.org/pre/abstract/10.1103/PhysRevE.108.014135 

Also: walk, noise, fluctuations, dance,  in: https://www.inkgmr.net/kwrds.html

Keywords: gst, walks, random walks, noise, fluctuations

# gst: influence of disorder on the spreading and entanglement properties of coined quantum walks.

AA << investigate the influence of disorder on the spreading and entanglement properties of coined quantum walks. Specifically, (AA) consider quantum walks on the line and explore the effects of quenched disorder in the coin operations. (They) find that coin disorder alters the usual ballistic transport properties of coined quantum walks considerably and yields an extremely slow dynamics with strong evidence for localization behavior. (They) investigate this slow dynamics by comparing different properties of the walker occupation probability with the standard Hadamard walk. (They) find that the walker distribution, and a number of properties associated with it, are significantly altered by the coin disorder. Special focus is given to the influence of coin disorder on entanglement properties. (AA) observe that generically, coin disorder decreases the coin-walker entanglement. The behavior of the entanglement properties further supports the premise that coin disorder induces localization in coined quantum walks. >>

Louie Hong Yao, Sascha Wald. Coined Quantum Walks on the Line: Disorder, Entanglement and Localization. arXiv: 2303.15978v1 [quant-ph]. doi: 10.48550/ arXiv.2303.15978. 28 Mar 28, 2023.

https://arxiv.org/abs/2303.15978

Also

Voli a casaccio. Notes. Oct 01, 2006. 

(quasi-stochastic poetry)

https://inkpi.blogspot.com/2006/10/2066-voli-casaccio.html

keyword 'disorder' in FonT

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

keyword 'disordine' in Notes 

(quasi-stochastic poetry)

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

keyword 'walk' | 'walking' in FonT

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

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

keyword 'passo lieve' | 'walk' | 'walking' in Notes

(quasi-stochastic poetry)

https://inkpi.blogspot.com/search?q=passo+lieve

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

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

Keywords: gst, disorder, quantum physics, walk, walking, coined quantum walks

# behav: learning walks related to home burrow navigation (among desert grassland scorpions Paruroctonus utahensis)

<< The Navigation by Chemotextural Familiarity Hypothesis (NCFH) suggests that scorpions use their midventral pectines to gather chemical and textural information near their burrows and use this information as they subsequently return home. For NCFH to be viable, animals must somehow acquire home-directed “tastes” of the substrate, such as through path integration (PI) and/or learning walks. >>️

AA << found that once animals established their home burrows, they immediately made one to several short, looping excursions away from and back to their burrows before walking greater distances. We also observed similar excursions when animals made burrows in level sand in the middle of the arena (i.e., no mound provided). These putative learning walks, together with recently reported PI in scorpions, may provide the crucial home-directed information requisite for NCFH. >>️

Douglas D. Gaffin, Maria G. Munoz, Marielle Hoefnagels. Evidence of learning walks related to scorpion home burrow navigation. bioRxiv 2021.12.28.474378; Dec 30, 2021. 

https://www.biorxiv.org/content/10.1101/2021.12.28.474378v1

Also

keyword 'walk' | 'walking' in FonT

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

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

keyword 'passo lieve' | 'walk' | 'walking' in Notes (quasi-stochastic poetry)

https://inkpi.blogspot.com/search?q=passo+lieve

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

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

Keywords: behav, walk, walking, learning walk, NCFH

# evol: Megalopta genalis, the bee that flies in the dark with dorsal landmark navigation

<< People -- who get lost easily in the extraordinary darkness of a tropical forest -- have much to learn from a bee that can find its way home in conditions 10 times dimmer than starlight. >>

AA << reveal that sweat bees (Megalopta genalis), find their way home based on patterns in the canopy overhead using dorsal vision. >>️️

<< For a human observer, the most obvious visual cues in the forest at night are gaps in the canopy when we look straight up because the sky is much brighter than the forest below, (..) We see a quite complex pattern of criss-crossing branches, but the bees'-eye-view is much less complex. They see broad blobs of light that vary in shape and position. We knew that ants could use canopy patterns to navigate as they walk through the forest, and we wondered if maybe bees were doing the same thing. >> Eric Warrant.

Dorsal navigation found in a flying insect. Smithsonian Tropical Research Institute. Jun 17, 2021. 

https://www.sciencedaily.com/releases/2021/06/210617101221.htm

Sandra Chaib, Marie Dacke, et al. 

Dorsal Landmark Navigation in a Neotropical Nocturnal Bee.  doi: 10.2139/ ssrn.3805162. Mar 15, 2021.

https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3805162

# life: I'm sorry, but this image has no predictive value

this image has no predictive value;  the Bot (relatively omniscient) will indicate the direction;  the Human (mumble grumble) will not be able to do other than walk it ... you bet, it's just a matter of time, relatively short time ... Are You Ready?

the image from  https://twitter.com/LDO_CTIO   (screenshot taken on Feb 25th, 2021 09:55 CET)

keyword 'ai' | 'bot' in FonT

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

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

keyword 'ia' | 'ai' | 'robota' in Notes (quasi- stochastic poetry)

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

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

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

# gst: the strong impact on nanosheets by the weak van der Waals force

<< Van der Waals is a weak force that allows neutral molecules to attract one another through randomly fluctuating dipoles, depending on distance. Though small, its effects can be seen in the macro world, like when geckos walk up walls. >> 

<< Van der Waals forces are everywhere and, essentially, at the nanoscale everything is sticky, (..) When you put a large, flat particle on a large, flat surface, there's a lot of contact, and it's enough to permanently deform a particle that's really thin and flexible. >> 

Matt Jones. 

<< the ubiquitous, "weak" van der Waals force was sufficient to indent a rigid silver nanosheet. The phenomenon suggests possible applications in nanoscale optics or catalytic systems. >>

<< In further experiments, (..) nanospheres could be used to control the shape of the deformation, from single ridges when two spheres are close, to saddle shapes or isolated bumps when the spheres are farther apart. >> 

Mike Williams. Weak force has strong impact on nanosheets. Rice University. Dec 15, 2020. 

https://phys.org/news/2020-12-weak-strong-impact-nanosheets.html

Sarah M. Rehn, Theodor M. Gerrard-Anderson, et al. Mechanical Reshaping of Inorganic Nanostructures with Weak Nanoscale Forces. Nano Lett. doi: 10.1021/ acs.nanolett.0c03383. Dec 10, 2020. 

https://pubs.acs.org/doi/10.1021/acs.nanolett.0c03383  

Also

keyword 'van der Waals' in FonT

https://flashontrack.blogspot.com/search?q=van+der+Waals

# gst: near a critical point, switching between exploitation and exploration, to approach life with Lévy's (chaotic) walk

<< Lévy walks are common biological movements. However, the functional advantages of Lévy walks emerging near a critical point are poorly understood. >>

AA << showed that there could be functional advantages associated with Lévy walks emerging near a critical point, including a large dynamic range to stimuli and highly flexible switching between exploitation and exploration. >>

Masato S. Abe. Functional advantages of Lévy walks emerging near a critical point. PNAS.  doi: 10.1073/ pnas.2001548117.  Sep 14, 2020.

https://www.pnas.org/content/early/2020/09/11/2001548117

Chaotic 'Lévy walks' are a good strategy for animals. Riken. Sep 17, 2020.

https://phys.org/news/2020-09-chaotic-lvy-good-strategy-animals.html   

Also

Lévy flight hypothesis, not only for predation ...  Nov 22, 2015.

https://flashontrack.blogspot.com/2015/11/s-gst-levy-flight-hypothesis-not-only.html

keyword 'Lévy' in FonT

https://flashontrack.blogspot.com/search?q=L%C3%A9vy&m=1

# gst: assembling colloidal spheres into rods of several lengths to walk above a pattern.

<< Detailed control over the motion of colloidal particles is relevant in many applications in colloidal science such as lab-on-a-chip devices. Here, (AA) use an external magnetic field to assemble paramagnetic colloidal spheres into colloidal rods of several lengths. The rods reside above a square magnetic pattern and are transported via modulation of the direction of the external magnetic field. >>

<< The rods behave like bipeds walking above the pattern. Depending on their length, the bipeds perform topologically distinct classes of protected walks. >>

<< Using such loops, (they) induce the collision of reactant bipeds, their polymerization addition reaction to larger bipeds, the separation of product bipeds from the educts, the sorting of different product bipeds, and also the parallel writing of a word consisting of several letters. >>

Mahla Mirzaee-Kakhki, Adrian Ernst, et al. Simultaneous polydirectional transport of colloidal bipeds. Nat Commun 11, 4670. doi: 10.1038/ s41467-020-18467-9. Sep 16, 2020.

https://www.nature.com/articles/s41467-020-18467-9

Controlled dynamics of colloidal rods. 

Bayreuth University. Sep 16, 2020. 

https://phys.org/news/2020-09-dynamics-colloidal-rods.html

# evol: traces of weird evolution, ancient crocodiles walked on two legs, like dinosaurs

<< some species of ancient crocodiles walked on their two hind legs like dinosaurs and measured over three meters in length. >>

<< At one site, the footprints were initially thought to be made by a giant bipedal pterosaur walking on the mudflat, we now understand that these were bipedal crocodile prints, (..) "And while footprints were everywhere on the site, there were no handprints. (..) Dinosaurs and their bird descendants walk on their toes. Crocodiles walk on the flat of their feet leaving clear heel impressions, like humans do. >> Anthony Romilio.

Ancient crocodiles walked on two legs like dinosaurs. University of Queensland. Jun 11, 2020.

https://phys.org/news/2020-06-ancient-crocodiles-legs-dinosaurs.html 

Kim, K.S., Lockley, M.G., et al. Trackway evidence for large bipedal crocodylomorphs from the Cretaceous of Korea. Sci Rep 10, 8680. doi: 10.1038/ s41598-020-66008-7. 

https://www.nature.com/articles/s41598-020-66008-7

# behav: walking with turning

<< Normal human locomotion in daily life involves walking with turning, not just straight line walking. (..) the metabolic rate while walking in circles increases with decreasing radius for fixed speed. (..) this increase in energy cost for turning has behavioral implications >>

<< to save energy, (..) humans should walk slower in smaller circles, slow down when path curvature increases when traveling along more complex curves, turn in place around a particular optimal angular speed, and avoid sharp turns but use smooth gentle turns while navigating around obstacles or while needing to turn while walking. >>

Geoffrey L. Brown, Nidhi Seethapathi, Manoj Srinivasan. Walking with turning: energy optimality explains walking behavior while turning and path planning. arXiv: 2001.02287v1 [q-bio.NC]. Jan 7, 2020.

https://arxiv.org/abs/2001.02287

# behav: 'run and tumble' behavior (among bacteria)

<< Bacteria in groundwater move in surprising ways. They can passively ride flowing groundwater, or they can actively move on their own in what scientists call "run and tumble" behavior.  >>

AA << noted a distinct run (movement in one direction) followed by a tumble (a sudden, random change in direction). By calculating the length and timing of these movements, they could develop a simple Continuous Time Random Walk (CTRW) model to predict how the bacteria would move. When compared to current models for bacterial remediation, the CTRW model was better at predicting bacterial transport in many circumstances. The CTRW model is the first step in developing and testing new reactive transport models that incorporate bacterial transport behavior.  >>

Rishi Parashar. Calculating 'run and tumble' behavior of bacteria in groundwater. Environmental Molecular Sciences Laboratory. Oct 31, 2019. 

https://m.phys.org/news/2019-10-behavior-bacteria-groundwater.html  

Xueke Yang, Rishi Parashar, et al. On Modeling Ensemble Transport of Metal Reducing Motile Bacteria. Scientific Reports volume 9, Article number: 14638. Oct 10, 2019. 

https://www.nature.com/articles/s41598-019-51271-0

# gst: dissolve into randomness, the kinetics

AA << have developed mathematical tools that send that shot across the bow-they determine when randomness emerges in any stochastic (random) system, answering a long-standing question: When does randomness set in during a random walk? >>

<< We are trying to describe an effect as exactly as possible irrespective of the cause. >> Rajan K. Chakrabarty

<< physicists normally solve problems by mathematically describing a cause and effect and marrying the two for a solution. But this new tool cares nothing about the cause, only about mathematically capturing the effect. >>

Tony Fitzpatrick. New tools reveal prelude to chaos. Washington University in St. Louis. Jun 6, 2018

https://m.phys.org/news/2018-06-tools-reveal-prelude-chaos.html  

Pai Liu, William R. Heinson, et al. Establishing the kinetics of ballistic-to-diffusive transition using directional statistics. Phys. Rev. E 97, 042102. Apr 4, 2018.

https://journals.aps.org/pre/abstract/10.1103/PhysRevE.97.042102  

# game: pulsating as a Toffoli gate: Parrondo's paradox with a three-state coin (heads, tails, and a side)

<< Parrondo's paradox - an apparent paradox in which two losing strategies combine to make a winning strategy - can emerge as a coin game with a single coin in the quantum realm, but only when the coin has three states (heads, tails, and a side) rather than the conventional two. >>

<< In the new study, [AA] have demonstrated a Parrondo's game using a three-state coin, which they represent with a qutrit, a quantum system with three states. >>

Lisa Zyga. Parrondo's paradox with a three-sided coin. Phys.org. July 11, 2018.

https://m.phys.org/news/2018-07-parrondo-paradox-three-sided-coin.html

Jishnu Rajendran, Colin Benjamin. Playing a true Parrondo's game with a three-state coin on a quantum walk. EPL. 2018; 122(4). June 28.

http://iopscience.iop.org/article/10.1209/0295-5075/122/40004/meta

https://arxiv.org/abs/1710.04033

Also

"Toffoli gate"

# qubit: three-qubit operation with the Toffoli gate for scalable semiconductor quantum processors. Mar 4, 2018.

https://flashontrack.blogspot.com/2018/03/qubit-three-qubit-operation-with.html

FonT

quando lessi per la prima volta in bibliografia circa il "Parrondo Game"  mi venne in mente una strategia che avevo immaginato e piu' volte usato a suo tempo - da meta'  anni '70 a tutti gli anni '80 (e oltre) - composta da una sorta di "tit-for-tat stocastico" cioe' una strategia di gioco di  "cooperazione/ defezione" con decisioni di scelta pilotate da "lancio di moneta" all'interno di due (e poi anche tre) scenari riconducibili al tipo Parrondo ... in pratica la generazione di scenari senz'altro di  "frontiera", evolutivi,  immediatamente generabili all'interno di situazioni (se-si-puo-dire ... or, namely, "sire-die-soup") del tipo "standard", supposte "lineari".  Anzicheforse.

1668 - ramificata tinnula (di carmina fluitantia). Jun 9, 2005.

https://inkpi.blogspot.com/2005/06/1668-ramificata-tinnula-di-carmina.html

"charlie"

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

# gst: random walk to describe a interplay between the inter-chain hopping and the intra-chain hopping in amorphous Polyimide nanofibers

AA << report the observation of a crossover of heat conduction behavior from three dimensions (3D) to quasi-one dimension (1D) in Polyimide(PI) nanofibers at a given temperature. A theoretical model based on the random walk theory has been proposed to quantitatively describe the interplay between the inter-chain hopping and the intra-chain hopping in nanofibers. This model explains well the diameter dependence of thermal conductivity and also speculates the upper limit of thermal conductivity of amorphous polymers in the quasi-1D limit. >>

Lan Dong, Qing Xi, et al. Dimensional crossover of heat conduction in amorphous Polyimide nanofibers. National Science Review. nwy004.  doi: 10.1093/nsr/nwy004. Jan 09,  2018.

https://academic.oup.com/nsr/advance-article/doi/10.1093/nsr/nwy004/4794956

<< The intrinsic structure of amorphous polymers is highly disordered with long, entangled molecular chains >>

Science China Press. "Random walk" of heat carriers in amorphous polymers. Mar 01, 2018.

https://m.phys.org/news/2018-03-random-carriers-amorphous-polymers.html

# n-usa: tracing Donald #POTUS: a new US triptych (?)

summary:

(1): accelerating the rise of (AI)  bots in the US

(2): pay attention to (Jay)walk; It could effectively be very dangerous ...

(3): gifts for  US Democrats

more (a): Chen' triptych, the first

2150 - il soffio di Chen. Jan 05, 2008.

http://inkpi.blogspot.it/2008/01/2150-il-soffio-di-chen.html

more (b): 'Donald' in:
http://flashontrack.blogspot.it/

(1) << If President  Trump  really does push companies  to base  more of their production  in the US then those  that specialise in  robotics  and  automation  will probably  be  the  winners >>

Paul Diggle. Why  Donald Trump is inadvertently going to accelerate  the rise of robots. Jan. 25, 2017.

http://www.businessinsider.com/hard-to-trump-robotics-2017-1

(2) << “Donald Trump has effectively created a way to deport individuals who have been accused, charged or convicted of anything from murder to jaywalking,” said Angelica Salas, executive director of the Coalition for Humane Immigrant Rights of Los Angeles >>

Janell Ross, Aaron C. Davis & Joel Achenbach. Immigrant community on high alert, fearing Trump’s ‘deportation force’.  Feb. 11, 2017

https://www.washingtonpost.com/national/immigrant-community-on-high-alert-fearing-trumps-deportation-force/2017/02/11/e5c30d06-f06f-11e6-9973-c5efb7ccfb0d_story.html

(3) David Weigel, Karen Tumulty. A gift and a challenge for Democrats: A restive, active and aggressive base. Feb. 11, 2017.

https://www.washingtonpost.com/powerpost/a-gift-and-a-challenge-for-democrats-a-restive-active-and-aggressive-base/2017/02/11/e265dd44-efef-11e6-b4ff-ac2cf509efe5_story.html

FonT: il prossimo futuro potrebbe essere "facile" da percorrere ...  percio' sara' "difficile"; forse (e si sottolinea forse) nell'ambito di "strane" discipline quali la neuro- farmacologia e la neuro- epi- genetica si trovera' "l'adatta stringa" ...

# zen: silence revolutions

<< Every  person  on  earth  has  a  field  of  silence  within.  Innate  to  the  ability  to  run  is  the  ability  to walk,  and  the  ability  to  walk  contains  the  ability  to  stand  still.  It  is  the  same  with  the  mind. Inherent  in  the  ability  to  talk  is  the  ability  to  think;  the  ability  to  think  contains  the  ability  to  think quietly--to  feel  or  intuit.  The  ability  to  think  quietly  holds  the  possibility  for  the  mind  to  be completely  still.>>

Ann  Purcell. The  Silence  Revolution 04/05/2016  04:18  pm  ET

http://m.huffpost.com/us/entry/the-silence-revolution_b_9612766.html

also: Inchingolo GM. 2123 - le dislocazioni pausali di Theo. Monday, February 26, 2007

http://inkpi.blogspot.it/2007/02/2123-le-dislocazioni-pausali-di-theo.html