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

lunedì 16 ottobre 2017

# gst: more on the three-body problem (695 families of collisionless orbits)

<< The famous three-body problem can be traced back to Isaac Newton in the 1680s >>

In a recent paper AA << numerically obtain 695 families of Newtonian periodic planar collisionless orbits of three-body system >>

Li, X. & Liao, S. More than six hundred new families of Newtonian periodic planar collisionless three-body orbits. Sci. China Phys. Mech. Astron. (2017) 60: 129511. doi: 10.1007/s11433-017-9078-5

https://link.springer.com/article/10.1007%2Fs11433-017-9078-5

the movies:

http://numericaltank.sjtu.edu.cn/three-body/three-body-unequal-mass-movies.htm

http://numericaltank.sjtu.edu.cn/three-body/three-body-unequal-mass.htm

http://numericaltank.sjtu.edu.cn/three-body/three-body.htm

Scientists discover more than 600 new periodic orbits of the famous three-body problem. Oct 12, 2017

https://m.phys.org/news/2017-10-scientists-periodic-orbits-famous-three-body.html

domenica 29 luglio 2018

# 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

martedì 22 febbraio 2022

# gst: apropos of a immaginary transition (with a tipping point), which simulates the chaotic interactions of three black holes.


<< The interactions between three bodies such as stars or planets or black holes cannot be predicted with an elegant formula. Moerman (Arend Moerman) therefore used a computer that calculates what happens for a short period of time and then uses the result for the next period of time. >>

AA << varied the masses of the three interacting black holes. They started with one solar mass and went up to a billion times the mass of the sun. >>

<< Around ten million solar masses, there appeared to be a tipping point. In the simulations, black holes that are lighter than about ten million solar masses mostly eject each other through a gravitational slingshot. Black holes heavier than about ten million solar masses start to merge. First, two black holes merge. The third black hole will follow later. The black holes merge because they lose kinetic energy and that is because they emit gravitational waves. >>

<< Arend's work (..) has led to a new understanding of how black holes become supermassive. In the simulations, we see that heavy black holes no longer endlessly move around each other, but that, if they are heavy enough, they collide pretty much instantly. >> Simon Portegies Zwart. 

Simulating chaotic interactions of three black holes. Netherlands Research School for Astronomy. Oct 20, 2021. 


Tjarda C. N. Boekholt, Arend Moerman, Simon F. Portegies Zwart. Relativistic Pythagorean three-body problem. Phys. Rev. D 104, 083020. 14 Oct 14,  2021. 


Also

more on the three-body problem (695 families of collisionless orbits). FonT. Oct 16, 2017. 


keyword 'black hole' | 'astro' in FonT



keyword 'transition' | 'transitional' in FonT



keyword 'transition' | 'transizion*' in Notes (quasi-stochastic poetry)




keywords: gst, black hole, three-body problem, transition, chaos, chaotic interaction, tipping point.



mercoledì 30 ottobre 2019

# gst: the three-body problem approach using deep neural networks

AA << show that an ensemble of solutions obtained using an arbitrarily precise numerical integrator can be used to train a deep artificial neural network (..) that, over a bounded time interval, provides accurate solutions at fixed computational cost and up to 100 million times faster than a state-of-the-art solver. >>

Philip G. Breen, Christopher N. Foley,  et al. Newton vs the machine: solving the chaotic three-body problem using deep neural networks. arXiv: 1910.07291v1 [astro-ph.GA] Oct 16, 2019

https://arxiv.org/abs/1910.07291

A neural net solves the three-body problem 100 million times faster. By Emerging Technology from the arXiv. 
Oct 26, 2019. 

https://www.technologyreview.com/s/614597/a-neural-net-solves-the-three-body-problem-100-million-times-faster/

Also

keyword "three" in FonT    

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

keyword "three" in Notes      

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


sabato 11 giugno 2022

# gst: switch to three players within the Parrondo game

<< Parrondo's paradox indicates a paradoxical situation in which a winning expectation may occur in sequences of losing games. There are many versions of the original Parrondo's games in the literature, but the games are played by two players in all of them. (AA) introduce a new extended version of games played by three players and a three-sided biased dice instead of two players and a biased coin in this work.  >>️

<< Figure 11 shows the result of combination switches A and B for the fair probabilities in set S_5. The simulation results are performed so on until 100 steps were done, and each step is averaged over 10000 repeats. This strategy, different from the others and even the original Parrondo's paradox, produces a fair expectation from two noisy switches in which the combination of two fair switches is fair. >>
Atiyeh Fotoohinasab. A new generalization of Parrondo's games to three players and its application in genetic switches.  arXiv: 2101.11401v2 [q-bio.PE]. Feb 2, 2021. 


Also

keyword 'parrondo' in FonT


keyword 'parrondo' in Notes  (quasi-stochastic poetry)


keyword 'three-body' in FonT


Keywords: gst, games, parrondo, three-body




lunedì 21 agosto 2017

# gene: 99 loci to drive general cognitive function

AA << combined cognitive and genetic data from the CHARGE and COGENT consortia, and UK Biobank (total N=280,360; age range = 16 to 102) >>

AA << found 9,714 genome-wide significant SNPs  [Single Nucleotide Polymorphism] (P<5 x 10-8) in 99 independent loci >>

<< Among many novel genes associated with general cognitive function were SGCZ, ATXN1, MAPT, AUTS2, and P2RY6 >>

Gail Davies, Max Lam, et al. Ninety-nine independent genetic loci influencing general cognitive function include genes associated with brain health and structure (N = 280,360). biorxiv. doi: 10.1101/176511 Aug18, 2017.

http://www.biorxiv.org/content/early/2017/08/18/176511

FonT

il sistema a 3 palle in fisica (three-body problem) qui genericamente estensibile a 99 ...

three-body problem:

Jon Cartwright. Physicists  Discover a Whopping 13 New  Solutions to Three-Body  Problem. Mar. 8, 2013

http://www.sciencemag.org/news/2013/03/physicists-discover-whopping-13-new-solutions-three-body-problem

Institute  of  Physics  Belgrade. Three-body gallery

http://suki.ipb.ac.rs/3body/

domenica 4 marzo 2018

# qubit: three-qubit operation with the Toffoli gate for scalable semiconductor quantum processors

<< The Toffoli gate is a three-qubit operation that changed the state of a target qubit conditioned on the state of two control qubits. It can be used for universal reversible classical computation, (..) >>

<< As a result, a single-step Toffoli gate can reduce the number of quantum operations dramatically, which can break the limit of coherence time and improve the efficiency of quantum computing >>

University of Science and Technology of China. Experimentally demonstrated a Toffoli gate in a semiconductor three-qubit system. March 1, 2018

https://m.phys.org/news/2018-03-experimentally-toffoli-gate-semiconductor-three-qubit.html

Hai-Ou Li, Gang Cao, et al. Controlled Quantum Operations of a Semiconductor Three-Qubit System. Phys. Rev. Applied 2018; 9.024015. doi: 10.1103/ PhysRevApplied.9.024015. Feb 15, 2018.

https://journals.aps.org/prapplied/abstract/10.1103/PhysRevApplied.9.024015

venerdì 2 giugno 2023

# gst: apropos of coexistence of coherent and incoherent oscillators, chaotic chimera attractors in a triangular network.

<< A prominent type of collective dynamics in networks of coupled oscillators is the coexistence of coherently and incoherently oscillating domains known as chimera states. >>️

<< In a three-population network of identical Kuramoto-Sakaguchi phase oscillators, stationary and periodic symmetric chimeras were previously studied on a reduced manifold in which two populations behaved identically. >>

<< In this paper, (AA) study the full phase space dynamics of such three-population networks. (They) demonstrate the existence of macroscopic chaotic chimera attractors that exhibit aperiodic antiphase dynamics of the order parameters. >>

<< The chaotic chimera states coexist with a stable chimera solution on the Ott-Antonsen manifold that displays periodic antiphase oscillation of the two incoherent populations and with a symmetric stationary chimera solution, resulting in tristability of chimera states. Of these three coexisting chimera states, only the symmetric stationary chimera solution exists in the symmetry-reduced manifold. >>️

Seungjae Lee, Katharina Krischer. Chaotic chimera attractors in a triangular network of identical oscillators. Phys. Rev. E 107, 054205. May 8, 2023.

Also: chimera, chaos, three balls, in https://www.inkgmr.net/kwrds.html

Keywwords: gst, chimera, bifurcations, chaos, synchronization


lunedì 27 dicembre 2021

# gst: reshaping Kuramoto model, when a collective dynamics becomes chaotic, with a surprisingly weak coupling.

<< The emergence of collective synchrony from an incoherent state is a phenomenon essentially described by the Kuramoto model (..) Collective synchronization is a phenomenon in which an ensemble of heterogeneous, self-sustained oscillatory units (commonly known as oscillators) spontaneously entrain their rhythms. This is a pervasive phenomenon observed in natural systems and man-made devices, covering a wide range of spatio-temporal scales, from cell aggregates to swarms of fireflies >>

<< However, this is only partly true, (..) Kuramoto’s perturbative phase-reduction approach is valid for weak coupling. Specifically, oscillator heterogeneity and interactions appear at zeroth and linear orders in the coupling constant, respectively. >> 

AA << have introduced the ‘enlarged Kuramoto model’; a population of phase oscillators in which three-body interactions enter in a perturbative way. Remarkably, this makes a world of difference, drastically reshaping the traditional Kuramoto scenario. The ‘enlarged Kuramoto model’ exhibits a variety of unsteady states, including collective chaos and hyperchaos. >>

Ivan Leon, Diego Pazo. Enlarged Kuramoto Model: Secondary Instability and Transition to Collective Chaos. arXiv: 2112.00176v1 [nlin.AO]. Nov 30, 2021.


Also

More on the three-body problem (695 families of collisionless orbits). FonT. Oct 16, 2017. 


Keywords: gst, behav, instability, Kuramoto model, three-body interactions, chaos, collective chaos, hyperchaos.

mercoledì 11 settembre 2019

# gst: apropos to try numerically to discover states with desired response properties in chaotic (i.e. normal - ab.normal) systems, by Hridesh, Deng, Jean-Jacques, Jeremy.

  <<
Systems with many stable configurations abound in nature, both in living and inanimate matter. Their inherent nonlinearity and sensitivity to small perturbations make them challenging to study, particularly in the presence of external driving, which can alter the relative stability of different attractors. Under such circumstances, one may ask whether any clear relationship holds between the specific pattern of external driving and the particular attractor states selected by a driven multistable system. To gain insight into this question, (AA)  numerically study driven disordered mechanical networks of bistable springs which possess a vast number of stable configurations arising from the two stable rest lengths of each spring, thereby capturing the essential physical properties of a broad class of multistable systems.  (AA) find that the attractor states of driven disordered multistable mechanical networks are fine-tuned with respect to the pattern of external forcing to have low work absorption from it. Furthermore,  (AA)  find that these drive-specific attractor states are even more stable than expected for a given level of work absorption.  (AA)  results suggest that the driven exploration of the vast configuration space of these systems is biased towards states with exceptional relationship to the driving environment, and could therefore be used to 'discover' states with desired response properties in systems with a vast landscape of diverse configurations.
  >>

Hridesh Kedia, Deng Pan, et al. Drive-specific adaptation in disordered mechanical networks of bistable springs. arXiv:1908.09332v1 [nlin.AO] Aug 25, 2019.    https://arxiv.org/abs/1908.09332 

Also

keyword "three" in: FonT    https://flashontrack.blogspot.com/search?q=three

keyword "three" in: Notes      https://inkpi.blogspot.com/search?q=three

giovedì 14 luglio 2016

# s-acad: imparare bene due accordi ...

<< impara bene due accordi; prima di imparare il terzo procurati un buon avvocato >>

Anonymous. Virgin Radio, http://www.virginradio.it. 2016.06.06 16:27

more (three body problem):

Jon Cartwright. Physicists  Discover  a  Whopping  13  New  Solutions  to  Three-Body  Problem. Mar. 8, 2013 , 4:30  PM

http://www.sciencemag.org/news/2013/03/physicists-discover-whopping-13-new-solutions-three-body-problem

Institute  of  Physics  Belgrade. Three-body gallery

http://suki.ipb.ac.rs/3body/

sabato 23 luglio 2022

# zoo: apropos of extreme dwarf entities, three new species of nano-hawk moths (Cautethia Grote, Sphingidae)

<< Hawk moths are known for being some of the largest night fliers in the insect world (..) three new species from The Bahamas are breaking records at the opposite end of the size spectrum. At about the length of a vitamin pill, they are among the smallest discovered. >>️

<< Hawk moths are a diverse group of insects, with some 1,700 species worldwide. In addition to their remarkable wingspans, they also have incredibly long proboscises, the straw-like tongues they use to siphon nectar.  The title for the world's longest proboscis is held by a hawk moth endemic to Madagascar, which comes in at just under 12 inches when fully unfurled. >>️

Brian V. Smith. New hawk moth species are among the smallest ever discovered. Florida Museum of Natural History. Jul 11, 2022. 


Jacqueline Y. Miller, Deborah L. Matthews, Riley J. Gott. Three new species of Cautethia Grote (Lepidoptera: Sphingidae) from the Lucayan Archipelago and keys to West Indies species. Insecta Mundi. 0937,  1-28. Jun 24, 2022 (pdf).


Also

Apropos of extreme dwarf entities, the nano-chameleon (Brookesia nana). FonT.  Feb 9, 2021.


keyword 'nano' in FonT


keyword 'nano' in Notes 
(quasi-stochastic poetry)


keywords: life, zoo, evol, dwarf, nano





sabato 23 luglio 2016

# n-socsci: a three-level social network among Hunter-Gatherer Societies

<< The new work reveals surprising similarities between the Agta of the Philippines and Mbendjele of the Republic of Congo. >>

<< In both places, individuals maintain a three-tiered social network that appears to buffer them against day-to-day shortfalls in foraging returns. >>

<< First is their immediate household, most often consisting of five or six individuals, second is a cluster of three to four closely related households who share food frequently, and third is the wider camp. >>

http://www.eurekalert.org/pub_releases/2016-07/cp-whc071316.php

Mark Dyble, James Thompson, et al.
Networks of Food Sharing Reveal the Functional Significance of Multilevel Sociality in Two Hunter-Gatherer Groups. Current Biology, 2016 DOI: 10.1016/j.cub.2016.05.064 Published: July 21, 2016

http://dx.doi.org/10.1016/j.cub.2016.05.064

lunedì 17 ottobre 2022

# life: a proposito di bizzarri scenari, qui un ipotetico scenario22 dipinto dal reale ...

img: Congo Square, New Orleans, Louisiana (wikipedia.org)

In definitiva qui si configurerebbe un - intrigante assai - scenario che, grosso modo, si potrebbe sinteticamente 'dipingere' in questi termini: 

(i) entità tre palle destrogire, animate aciclicamente da interazioni attrattive- repulsive a causa di già a suo tempo disvelate pulsioni neuro cognitive arcaiche, riconducibili a visioni neuro predatorie CTZ estreme, perciò ipoteticamente (si fa per dire) a-priori ad esiti immediati e in prospettiva drammaticamente lesivi- autolesivi; 

(ii) entità tre palle levogire, animate da analoghe pulsività, purtuttavia in.forme  tenui, in modalità sottotraccia, frenate da feed-back a modalità allosterica, ombreggiate, stemperate, diluite, discrete, timidamente celate, talvolta fantasmatiche perfino, quasi ma non del tutto mai silenti, perciò anch'esse a tutti gli effetti operative, sebbene a dinamiche più fluide, lente, meno dirompenti rispetto alle destrogire; 

(iii) entrambe l'Entità destrogire e levogire animat(t)rici,  generat(t)rici di dinamiche bi-multi-forcate, transeunti, con picchi di improvvisi aciclici burst ad effetti RAG-time diretti e inversi;

(iv) lo scenario al contorno e forse anche all'interno, nei vari specifici contesti, riconducibile grosso modo alla formazione aciclica di ipotetici buchi neri non inerti, caratterizzati da aciclicità in compressione e dilatazione - come fossero fisarmoniche - animati (in perpetuo?) da multi vortici in ingresso e in uscita;

Non so se basti compulsare un manuale delle funzioni speciali per formalizzare in qualche adatto topo-modo questo pulsatile multi scenario, purtuttavia assolutamente intrigante ... 

Qui una AI operativa nella formalizzazione di analogie potrebbe modellizzare, forse ... (e.g. https://flashontrack.blogspot.com/2021/08/aibot-mechanism-of-analogy-could-be.html )

Quello che appare evidente è la complessità d'insieme, un bizzarro dipinto, uno scenario dinamico che, al confronto, le storiche danze in Congo Square potrebbero sembrare semplici, ordinate coreografie ... queste, rispetto a quelle, delle topo-forme  'primitive', per dire ed anzicheforse.

In sintesi, i riferimenti (ovviamente generici) del bizzarro scenario: 

(:) buco nero con vortici 

(:) scenari generati da 3 palle 
(a)
(b)

(:) effetti RAG-time (RAG: Ralph, Al, George) 
(a) (quasi-stochastic poetry)
(b)

(:) pulsioni predatorie supportate / giustificate da visioni neuro- post- CTZ nelle modalità arcaiche oppure friendly 

(:) Congo Square, jazz 
(a)
(b)
(c) (quasi-stochastic poetry)

(:) approccio Bertalanffy 

(:) un bizzarro tracciatore 

Anche

"Amico, qualunque cosa suonerai ... "
(a) (quasi-stochastic poetry)
(b)

Keywords: life, gst, Congo Square, jazz, Jelly Roll, transition, three-body, RAG, CTZ, black hole, bizarre tracker




mercoledì 17 marzo 2021

# phys: trace the birth and evolution of a quasiparticle entity

<< The idea of quasiparticles was first introduced in the 1930s by physicist Lev Landau, who was trying to gain a better understanding of complex quantum systems. >>

<< Over the past decades, physicists worldwide have been trying to gain a better understanding of non-equilibrium dynamics in quantum many-body systems. Some studies investigated what are known as quasiparticles, disturbances or entities in physical systems that exhibit behavior similar to that of particles. >>

In this study AA << observed three distinct regimes of impurity evolution marked by dynamic transitions. These regimes then link initial few-body and later many-body physical dynamics. >>

Ingrid Fadelli. Observing the birth of a quasiparticle. Mar 11, 2021.


<<  These results offer a systematic picture of polaron formation from weak to strong impurity interactions. They reveal three distinct regimes of evolution with dynamical transitions that provide a link between few-body processes and many-body dynamics. Our measurements reveal universal dynamical behaviour in interacting many-body systems and demonstrate new pathways to study non-equilibrium quantum phenomena. >>

Magnus G. Skou, Thomas G. Skov, et al. Non-equilibrium quantum dynamics and formation of the Bose polaron. 
Nat. Phys. (2021). doi: 10.1038/ s41567-021-01184-5. Feb 25, 2021.


"three distinct regimes"  




lunedì 28 dicembre 2015

# s-ecol-food: lettuce three times worse ?

<< Contrary to recent headlines (..) eating a vegetarian diet could contribute to climate change >>

<< Eating lettuce is over three times worse in greenhouse gas emissions than eating bacon >>

http://www.cmu.edu/news/stories/archives/2015/december/diet-and-environment.html

<< This article measures the changes in energy use, blue water footprint, and greenhouse gas (GHG) emissions associated with shifting from current US food consumption patterns to three dietary scenarios >>

Michelle S. Tom, Paul S. Fischbeck, Chris T. Hendrickson. Energy use, blue water footprint, and greenhouse gas emissions for current food consumption patterns and dietary recommendations in the US. Environment Systems and Decisions, 2015; DOI: 10.1007/s10669-015-9577-y

http://link.springer.com/article/10.1007%2Fs10669-015-9577-y

venerdì 30 aprile 2021

# gst: immediate 'shot', the three second time window in art, music, poems and language processing

<< Is there a universal time constant for poetic lines when people read them aloud or recite them by heart? Turner and Pöppel (1988) collected over 20 types of poetry, varying from East to West and from modern societies to indigenous cultures, and found a constant of ~3 s for the duration of poetic lines. >>️

<< This observation indicates a production– perception synchrony of ~3 s, which means that we not only tend to recite poems  (and speech in a more general sense; discussed later) with a 3-s pattern but also appreciate poems aesthetically within the same temporal frame. This temporal preference for a 3-s pattern and not a 1-s or a 10-s pattern, which linguistically would be possible, indicates presumably a profound evolutionary basis. The temporal modulation effect of the 3-s window on aesthetic appreciation may also motivate to look for other concepts and phenomena of the cognitive and neural basis of aesthetic perception in general and in detail, as has been partly already done for decision processes, the visual arts, and music (Avram et al., 2013; Bao et al., 2016; Bao et al., 2017; Park et al., 2014; Park et al., 2015; Pöppel, 1989a). >>

Xinchi Yu, Yan Bao. The three second time window in poems and language processing in general: Complementarity of discrete timing and temporal continuity.  PsyCh Journal. Vol 9, Issue 4 p. 429-443. doi: 10.1002/ pchj.390. Aug 26, 2020. 


<< the composer Peter Michael Hamel  (..) decided to compose a string quartet, which he called The Time Frame. This time window (the three second time window), which is an anthropological universal, provides an operative basis for effortless communication, empathic relationships to others, and it is the brain's way to integrate continuity and simultaneity of what is experienced in a complementary mode. >>️

Peter Michael Hamel. Through the self to music: The self as the creative origin for composing in time frames. Psych J. 10(2):249-253. doi: 10.1002/ pchj.446. Apr 12, 2021


Also 

Ramificata tinnula (di carmina fluitantia). Notes (quasi-stochastic poetry). Jun 09, 2005.


Elettrico Charlie (Seven come eleven). 
Notes (quasi-stochastic poetry). Feb 01, 2007. 


Il pseudomotore di Shostakovich. Notes (quasi-stochastic poetry). Nov 15, 2006. 


keyword 'jazz' in Notes (quasi-stochastic poetry)


FonT 

Queste considerazioni di Xinchi Yu e  Yan Bao potrebbero anche indicare una sorta di predisposizione neurofisiologica individuale all' 'immediato Satori' ... 









venerdì 24 giugno 2022

# gst: non-trivial behaviors of a rotating (physical) double pendulum

<< The double pendulum, a simple system of classical mechanics, is widely studied as an example of, and testbed for, chaotic dynamics. In 2016, Maiti et al. studied a generalization of the simple double pendulum with equal point-masses at equal lengths, to a rotating double pendulum, fixed to a coordinate system uniformly rotating about the vertical. In this paper, (AA) study a considerable generalization of the double pendulum, constructed from physical pendula, and ask what equilibrium configurations exist for the system across a comparatively large parameter space, as well as what bifurcations occur in those equilibria. >>️

<< the non-trivial bifurcation (AA) have found (..), may actually be rightly understood as three additional bifurcations: there is a narrow region, approximately the ‘crease’ of the surface in Fig. 5, within which a vertical line (..) intersects the surface three times; (..). Thus three non-trival bifurcations would be expected in the corresponding bifurcations plots. >>️

Jonathan Tot, Robert H. Lewis. On the Equilibria and Bifurcations of a Rotating Double Pendulum. arXiv:2204.12437v2 [math.DS]. May 7, 2022. 


Also

keyword 'pendulum' in FonT


keyword 'pendolo' | 'pendola' in Notes
(quasi-stochastic poetry)



Keywords: gst, pendulum, double pendulum, behavior, chaos 








venerdì 27 dicembre 2019

# phys: three forms of ambiguity in the definition of entanglement


<< A more general definition (of entanglement) was published by Thaller, (B. Thaller, Advanced Visual Quantum Mechanics, (Springer 2005) p218) "A state of a compound system is called entangled if it cannot be written as a single tensor product of subsystem states. A state in the product form is called unentangled or separable."  >>

The paper << discusses experiments with single-particle systems, some of whose states appear to be entangled. (..) Three forms of ambiguity are discussed. The choice of state-space and its dimensions is a matter of taste. There is not an a-priori natural partitioning of the state-space. The observables are not necessarily experimentally accessible and only determined by theory-laden extrapolation from experimental results. >>

Robert Shaw. Single-particle entanglement and three forms of ambiguity. arXiv:1912.11349v1 [physics.hist-ph]. Dec 22, 2019

https://arxiv.org/abs/1912.11349

giovedì 11 giugno 2020

# life: apropos of widespread racism, three in four people (probably even more than three) hold unconscious negative view of world: study

<< Most Australians tested for unconscious bias hold a negative view of Indigenous Australians which can lead to widespread racism, new analysis from The Australian National University (ANU) shows. >>

<< The ANU researchers say 75 per cent of Australians tested using the Implicit Association Test by a joint initiative of universities including Harvard, Yale and the University of Sydney hold a negative implicit or unconscious bias against Indigenous Australians. >>

Three in four people hold negative view of Indigenous people: study. Australian National University. June 9, 2020.


Siddharth Shirodkar. Bias against Indigenous Australians: Implicit association test results for Australia. Journal of Australian Indigenous Issues. Vol 22 Issue 3-4.  Dec 2019.


Also

# brain: immagini #CTZ, cicliche fantasmatiche pervasive visioni ricorrenti. FonT. Jun 29, 2019.