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martedì 31 ottobre 2023

# gst: how to create a helix from a straight rod, “twist” or “bend” approaches.

<< There are two independent ways of creating a helix from a straight rod: curl the rod into a circle and then twist the rod all along its length to convert the ring into a helix (“twist” method), or deform the rod into a sine wave and then bend it with a sinusoidal distortion that curls at right angles to the first sine wave (“bend” method). Both procedures produce the same shape, but they generate different internal stresses within the rod, and their implementations require different amounts of energy. >>️

AA << say that their experiments could serve as a model for many physical systems that undergo handedness transitions, including the tendrils of plants, the flagella of microorganisms, and the strands of DNA molecules.  >>
David Ehrenstein. Two Experimental Observations of Helix Reversals. Physics 16, s158. Oct 24, 2023.  

Paul M. Ryan, Joshua W. Shaevitz,  Charles W. Wolgemuth. Bend or Twist? What Plectonemes Reveal about the Mysterious Motility of Spiroplasma. Phys. Rev. Lett. 131, 178401. Oct 24, 2023. 

Emilien Dilly, Sebastien Neukirch, Julien Derr, Drazen Zanchi. Traveling Perversion as Constant Torque Actuator. Phys. Rev. Lett. 131, 177201. Oct 24, 2023. 

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

Keywords: gst, elastic, elastic deformation, swimming



sabato 21 ottobre 2023

# gst: local elastic properties of strongly disordered matter

<< The local elastic properties of strongly disordered material are investigated using the theory of correlated random matrices. A significant increase in stiffness is shown in the interfacial region, the thickness of which depends on the strength of disorder. It is shown that this effect plays a crucial role in nanocomposites, in which interfacial regions are formed around each nanoparticle. >>️

D. A. Conyuh, A. A. Semenov, Y. M. Beltukov. Effective elastic moduli of composites with a strongly disordered host material. Phys. Rev. E 108, 045004. Oct 20, 2023. 

Also: elastic, noise, particle, nano, in https://www.inkgmr.net/kwrds.html

Keywords: gst, elastic, noise, particle, nano


venerdì 20 ottobre 2023

# life: call for four Parrondo's paradox peacekeeper players

<< US President Joe Biden has said world history is at "an inflection point" as he made the case for a "smart investment" of ... >> Ukraine, Israel, Taiwan.
Holly Honderich, Sarah Smith. Biden seeks 'vital' (..) aid for Israel and Ukraine. BBC News, Oct 20, 2023. 

Also: Switch to three players within the Parrondo game. FonT. Jun 11, 2022.


Also: "Parrondo"[TIAB], in https://pubmed.ncbi.nlm.nih.gov/


Keywords: life, game, Parrondo, Potus, war, nfulaw


martedì 17 ottobre 2023

# 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.

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

Keywords: games, parrondo, walk, noise




sabato 14 ottobre 2023

# gst: emergence of chimeras driven by non-normality


<< The emergence of order in nature manifests in different phenomena, with synchronization being one of the most representative examples. >>️

<< Particular attention has been paid to the emergence of chimera states, where subsets of synchronized oscillations coexist with asynchronous ones. Such coexistence of coherence and incoherence is a perfect example where order and disorder can persist in a long-lasting regime. >>

<< Based on a symmetry-breaking mechanism, in this paper, (AA) shed light on the role that non-normality, a ubiquitous structural property of real networks, has in the emergence of several diverse dynamical phenomena, e.g., amplitude chimeras or oscillon patterns. >>️

<< Specifically, (they) demonstrate that the prevalence of source or leader nodes in networks leads to the manifestation of phase chimera states. >>️

Riccardo Muolo, Joseph D. O'Brien, et al. Persistence of chimera states and the challenge for synchronization in real-world networks. arXiv: 2306.00237v1 [nlin.PS]. May 31, 2023.

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

Keywords: gst, chimera, network, synchronization, swarm, noise, order, disorder, normal


mercoledì 11 ottobre 2023

# phys: a quantum gravity hypothesis on infalling matter (hunting for extreme Kerr black holes)

 << Quantum gravity refers to a group of theories—string theory, for example—that aims to reconcile the microscopic world of quantum physics with the macroscopic world of general relativity. >> 

 << Now theoretical work by Grant N.  Remmen (et al) shows that celestial objects called extremal Kerr black holes are highly sensitive to quantum gravity. >> 
 
  << A Kerr black hole is a rotating, electrically neutral black hole. It is said to be extremal if it has the highest possible angular momentum that is compatible with its mass.  Extremal Kerr black holes have yet to be detected, but many theories predict their existence. >> 
 
 They << point out that quantum corrections to general relativity would provide specific contributions to a quantity called the effective action, which describes the dynamics of a gravitational field. (..) under quantum gravity, the event horizon would develop curvature singularities—regions where the gravitational field is infinitely strong. >> 
 
 << the next step is to hunt for extremal Kerr black holes and to try to detect these curvature singularities through their effect on infalling matter. >> 

Ryan Wilkinson. New Physics Magnified in Spinning Black Holes. Physics 16, s117. Aug 31, 2023.

Gary T. Horowitz, Maciej Kolanowski, Grant N. Remmen, Jorge E. Santos. Extremal Kerr Black Holes as Amplifiers of New Physics. Phys. Rev. Lett. 131, 091402. Aug 31, 2023.

Also: Ingrid Fadelli. Theoretical study shows that Kerr black holes could amplify new physics. Phys.org. Sep 22, 2023. 

Also: astrophysics, black hole, in: https://www.inkgmr.net/kwrds.html

Keywords: astrophysics, black holes



mercoledì 4 ottobre 2023

# life: a proposito di '1or2achoos' (da Wuhan (?)), qui la cronologia

a proposito di '1or2achoos' (da Wuhan (?)), qui la cronologia di inizio dei 6 flu|covid che ho contratto dal gen2020 ad oggi con i relativi tempi di 'smorzamento' dell'infezione, trattati nebulizzando una miscela di alcool e H2O2 ( https://flashontrack.blogspot.com/2022/07/life-aproposito-di-1or2achoos-da-wuhan.html )

(1) 2020.04.11-16:04 ~12h (non vaccinato)
(2) 2021.09.01-07:40 ~12h (non vaccinato)
(3) 2022.06.11-08:26 18-36h (+1mese post vaccino, 3dosi)
(4) 2022.12.24-07:52 ~24h 
(5) 2023.02.28-12:09 ~24h 
(6) 2023.04.08-09:32 24-36h 

I tempi necessari per 'spegnere' questi  flu|covid sono tutti notevolmente inferiori (~80%) rispetto alle pregresse forme di flu che ho contratto delle quali ho memoria.

Invece non ho altre parole da aggiungere per commentare i diversi argomenti associabili a '1or2achoos' dal febbraio 2020 ad oggi.

Potrei (e.g. expectedepidemic, lockdown, greenpass, indicatori, statistiche, accademieacucciabili, sadichepredazioni, bucodibilancio, pastroky, ...) nelle bizzarre forme della poetica quasistocastica ( https://inkpi.blogspot.com/ ), ma mi astengo.

Anche: "Ricordo che quando si era ragazzi". in: "il pino di takata matsubara". Notes. Apr 1, 2011. https://inkpi.blogspot.com/2011/04/2157-il-pino-di-takata-matsubara.html

Anche: "e Da-Li' si sparse pell'aere". in: "cracker tendenziali". Notes. Apr 4, 2008. https://inkpi.blogspot.com/2008/04/cracker-tendenziali-around-matter.html

Anche: "in attesa del beffardo tsunami". in: "onda di carambola". Notes. Nov 29, 2004. 

Anche: "aproposito di '1or2achoos' (da Wuhan (?)) ...". FonT. Jul 13, 2022. https://flashontrack.blogspot.com/2022/07/life-aproposito-di-1or2achoos-da-wuhan.html

Anche: 1or2achoos, sars, covid, virus, pastroky, in: 

Keywords: life, virus, flu, coronavirus,  sarscov2, covid19, 1or2achoos, mask



lunedì 2 ottobre 2023

# gst: anisotropic active depletion around a self-propelled non-interactive colloids; three characteristic states could be identified.

<< Active colloids in a bath of inert particles of smaller size cause anisotropic depletion. >>️

Here AA << combine mesoscale hydrodynamic simulation as well as theoretical analysis to examine the physical origin for the active depletion around a self-propelled noninteractive colloid. >>️

Their << results elucidate that the variable hydrodynamic effect critically governs the microstructure of the depletion zone. Three characteristic states of anisotropic depletion are identified, depending on the strength and stress of activity. >>️

<< Furthermore, (AA) demonstrate that such depletion in nonequilibrium results in various clusters with ordered organization of squirmers, which follows a distinct principle contrary to that of the entropy scenario of depletion in equilibrium. >>
Lijun Dai, Haixiao Wan, et al. Hydrodynamic Anisotropy of Depletion in Nonequilibrium. Phys. Rev. Lett. 131, 134002. Sep 27, 2023. 

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

Keywords: gst, particles, colloids, depletion, squirmers, self-propulsion systems