# gst: disorder can induce and modulate topological structures

 << One of the boons of topological insulators is that their conducting edge states are protected from disorder in the material’s structure. Turn up the disorder too much, however, and these topological features are usually lost. In 2018, experiments demonstrated the opposite behavior: in so-called topological Anderson insulators (TAIs), the addition of disorder can generate protected edge states, turning a trivial insulator into a topological one. Now, a team (..) reports a new type of TAI realized in a photonic crystal. Their experiments show that the crystal exhibits a wealth of topological phenomena that hadn’t been seen previously. >> 

Matteo Rini. Let Disorder Dictate Topology. Physics 13, s123. Sep 24, 2020. 

https://physics.aps.org/articles/v13/s123    

 AA << directly observe the disorder-induced topological phase transition from a trivial insulator to a TAI with robust chiral edge states. (They) also demonstrate topological heterostructures that host edge states at interfaces between domains with different disorder parameters. >> 

Gui-Geng Liu, Yihao Yang, et al. Topological Anderson Insulator in Disordered Photonic Crystals. Phys. Rev. Lett. 125, 133603. Sep 24, 2020.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.125.133603

# gst: structured amorphous with enforced fragmentation

<< Many substances with different chemical and physical properties, from diamonds to graphite, are made up of carbon atoms. Amorphous forms of solid carbon do not have a fixed crystal structure and consist of structural units—nanosized graphene particles. >>

(AA) << studied the structure of amorphous carbon and suggested classifying it as a separate type of amorphous solid bodies: a molecular amorphic with enforced fragmentation. (..) sp2 amorphous carbon is a fractal structure based on nanosized graphene domains that are surrounded by atoms of other elements (hydrogen, oxygen, nitrogen, sulfur, and so on). >> 

<< The discovery and experimental confirmation of the graphene nature of the 'black gold' will completely change the theory, modeling, and interpretation of experiments with this class of substances. However, some questions remain unanswered. What does solid-state physics make of this amorphous state of solid carbon? What role does amorphous carbon with sp2-hybridization play in the bigger picture?  >>  Elena Sheka.

Physicists describe a new type of amorphous solid bodies. RUDN University. Dec 03, 2020. 

https://phys.org/news/2020-12-physicists-amorphous-solid-bodies.html 

E. F. Sheka ,Ye. A. Golubev, N. A. Popova. Amorphous state of sp2 solid carbon. Fullerenes, Nanotubes and Carbon Nanostructures. doi: 10.1080/ 1536383X.2020.1815713. Sep 03, 2020.

https://www.tandfonline.com/doi/full/10.1080/1536383X.2020.1815713 

Also 

word 'allotropy' in Cambridge Dictionary

https://dictionary.cambridge.org/dictionary/english/allotropy

# gst: apropos of poetry, poetry inside science ... and vice versa

<< Poetry is a great tool for interrogating and questioning the world,  (..) There are so many amazing science stories out there that people don't know about because they are hidden in the jargon of scientific papers, (..) Poetry levels hierarchies of intellect, >> Sam Illingworth

<< A good science poem is one that calls upon a scientific idea but then tweaks it and elevates it in a way that a simple description can’t, >> Sunayana Bhargava

Katherine Wright. Scientists Take on Poetry. Physics 13, 150. Sep 22, 2020. 

https://physics.aps.org/articles/v13/150   

Also

Notes (quasi-stochastic poetry)

https://inkpi.blogspot.com/

# brain: the drug ISRIB reverses age-related cognitive decline within days (in mice) and even enhance cognition in healthy animals

<< Just a few doses of an experimental drug can reverse age-related declines in memory and mental flexibility in mice, (..)  The drug, called ISRIB (ISR InhiBitor), has already been shown in laboratory studies to restore memory function months after traumatic brain injury (TBI), reverse cognitive impairments in Down Syndrome , prevent noise-related hearing loss, fight certain types of prostate cancer , and even enhance cognition in healthy animals. >>

<< In the new study, researchers showed rapid restoration of youthful cognitive abilities in aged mice, accompanied by a rejuvenation of brain and immune cells that could help explain improvements in brain function. >>

<< ISRIB's extremely rapid effects show for the first time that a significant component of age-related cognitive losses may be caused by a kind of reversible physiological "blockage" rather than more permanent degradation, >> Susanna Rosi.

<< The data suggest that the aged brain has not permanently lost essential cognitive capacities, as was commonly assumed, but rather that these cognitive resources are still there but have been somehow blocked, trapped by a vicious cycle of cellular stress, (..)  Our work with ISRIB demonstrates a way to break that cycle and restore cognitive abilities that had become walled off over time. >> Peter Walter.

Drug reverses age-related cognitive decline within days. University of California, San Francisco. Dec 01, 2020.

https://medicalxpress.com/news/2020-12-drug-reverses-age-related-cognitive-decline.html

Karen Krukowski, Amber Nolan, et al. 

Small molecule cognitive enhancer reverses age-related memory decline in mice. eLife. doi: 10.7554/ eLife.62048. Dec 1, 2020.

https://elifesciences.org/articles/62048  

# phys: stable vortex loops intersected by point singularities (in magnets)

<< Vortex rings are remarkably stable structures that occur in a large variety of systems (..) Although vortex rings have also been predicted to exist in ferromagnets, they have not yet been observed. >>

AA << imaged three-dimensional structures forming closed vortex loops in a bulk micromagnet. The cross-section of these loops consists of a vortex–antivortex pair and, on the basis of magnetic vorticity (they) identify these configurations as magnetic vortex rings. >>

<< In addition, (they) observe stable vortex loops intersected by point singularities at which the magnetization within the vortex and antivortex cores reverses. >>

Claire Donnelly, Konstantin L. Metlov, et al. Experimental observation of vortex rings in a bulk magnet. Nature Physics. doi: 10.1038/ s41567-020-01057-3. Nov 30,  2020.

https://www.nature.com/articles/s41567-020-01057-3

Magnetic vortices come full circle. 

Paul Scherrer Institute. Nov 30, 2020.

https://phys.org/news/2020-11-magnetic-vortices-full-circle.html

# life: apropos of ghosts, a bizarre answer to my previous post, the 'cosmic ghost' ...

<<  They were on a mission to count sheep when they found something they had not counted on. >>

Peter Szekely. Reuters: Space oddity? Monolith in Utah desert mystifies helicopter crew. Nov 25, 2020.

https://www.reuters.com/article/us-usa-monolith/space-oddity-monolith-in-utah-desert-mystifies-helicopter-crew-idUSKBN28501O

Also

apropos of unsubstantiated belief (e.g. paranormal belief, anomalistic psychology, ...) why so many people believe in 'ghosts'. FonT.  19 Nov 19, 2020.

https://flashontrack.blogspot.com/2020/11/life-apropos-of-unsubstantiated-belief.html

# life: apropos of unsubstantiated belief (e.g. paranormal belief, anomalistic psychology, ...) why so many people believe in 'ghosts'.

<< Unlikely as it might seem in the cold light of day, ghosts and hauntings are a mainstream area of belief. Recent studies by YouGov in the UK and the USA show that between 30% and 50% of the population says they believe in ghosts. Belief in ghosts also appears to be global, with most (if not all) cultures around the world having some widely accepted kind of ghosts. >> 

<< The existence of a ghost as an incorporeal (bodyless) soul or spirit of a dead person or animal is contrary to the laws of nature as we understand them, so it seems there is something here that calls for explanation. We can look at the worlds of literature, philosophy and anthropology for some of the reasons why people are so keen to believe. >> 

<< Looking at how the brain works, the experience of hallucinations is a lot more common than many people realise. The SPR (Society for Psychical Research), founded in 1882, collected thousands of verified first-hand reports of visual or auditory hallucinations (..)   https://psi-encyclopedia.spr.ac.uk/articles/ghosts-and-apparitions-psi-research-overview#footnote52_nux8rmw   (..) Another source of hallucinations is the phenomenon of sleep paralysis, (..) >> 

<< According to the Dutch philosopher Baruch Spinoza, belief comes quickly and naturally, whereas scepticism is slow and unnatural. In a study of neural activity, Harris and colleagues discovered that believing a statement requires less effort than disbelieving it. >>

<<  Given these multiple reasons for us to believe in ghosts, it seems that the belief is likely to be with us for many years to come. >> 

Anna Stone. ‘I see dead people’: why so many of us believe in ghosts. 

Oct 30, 2020. 

https://theconversation.com/i-see-dead-people-why-so-many-of-us-believe-in-ghosts-148886

Also

keyword 'paranormal belief' in PubMed

https://pubmed.ncbi.nlm.nih.gov/?term=paranormal+belief

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

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