User:Lumos3/sandbox

Author Haroon Rashid
Author Haroon Rashid is the artist's name of Indian poet Haroon Rashid.

He has received worldwide recognition, for his poem about the Covid pandemic called 'We Fell Asleep In One World' aka 'The Earth Poem'.

He comes from Jammu and Kashmir, region of India. He has a Bachelor in Commerce and Double Post Graduation degrees in English Literature and Public Administration.

Works
Among his writings are ; 'We Fell Asleep In One World' aka 'The Earth Poem', 'Suicide Poem', 'Come Back From The Heaven', ‘Skin’, 'Will Meet Again', 'Human Trafficking', 'Humanity Poem', 'Faith', 'Mother', 'Spiritual Love', 'The World', 'Media', 'Human In Uniform', 'Get Up', 'Kashmir', 'Meet A Person' so on along with Endless Quotes.

Weighted blanket
Weighted blankets are therapeutic blankets that have weights added within the fabric. They weigh between 5 to 30 pounds. The extra weight on the body simulates the hands-on pressure of being hugged or held and can help calm a nervous individual. They are commonly used in psychiatric units and occupational therapy to help comfort restless people.

Weighted blankets are usually made of cotton, or a soft material, with  glass  plastic beads stitched inside to give them added weight.

Use of the weighted blanket has been found to benefit people with autism, ADHD, anxiety, insomnia, osteoarthritis and  chronic pain. They have also been used in stressful medical procedures like teeth extractions.

https://www.healthline.com/health/anxiety/do-weighted-blankets-work#who-may-benefit https://www.cosmopolitan.com/uk/worklife/a31927993/weighted-blanket-uk/ https://www.forbes.com/sites/forbes-personal-shopper/2020/12/02/best-weighted-blankets-2020/ https://www.pennmedicine.org/updates/blogs/health-and-wellness/2019/february/weighted-blankets

Siobhan Wall
Siobhan Wall (born - 1961) is a British author, journalist artist and academic. She is noted for her series of guides about tranquil places in busy cities, including Quiet New York, Quiet Amsterdam, Quiet Paris, Quiet Barcelona and Quiet London. She is the author of numerous articles on contemporary art.

She studied at Cambridge University, followed by a degree in Fine Art at Central St Martin's College of Art and Design, and an MA in Visual Culture at Middlesex University, London.

She has worked as a senior lecturer, teaching photography, cultural studies, video production and fine art for over ten years at universities in London ,Oxford and Amsterdam.

https://siobhanwall.com/?page_id=6

https://siobhanwall.com/ Personal home page

https://www.theguardian.com/travel/2012/jul/27/peace-quiet-art-london-days-out Crowd-free places: My perfect London day out by the author of Quiet London

https://www.ft.com/content/3e1fde32-12c1-11e4-93a5-00144feabdc0 Five of the best quiet London eateries JULY 25 2014

References

Gap surface plasmon
A Gap surface plasmon (GSP) can arise when electromagnetic radiation of the right wavelength meets  a solid metasurface built up from  a subwavelength thin dielectric spacer sandwiched between an optically thick metal film and arrays of metal sub-wavelength elements arranged in a strictly or quasi-periodic fashion. 1 2

Metasurfaces are two-dimensional arranged metamaterials with unique engineered properties in the spectral and spatial manipulation of electromagnetic waves. They are ultra-thin planar structures and offer extraordinary phase shift, amplitude modulation or polarization transition by patterning nanoscale dense antenna arrays or slits. 3 4

A plasmon is a quasiparticle which arises from the quantization of plasma oscillations and these are confined in the geometry of the materiel in the carefully engineered gaps.

4 https://ui.adsabs.harvard.edu/abs/2016SPIE.9883E..0RP/abstract

3

https://www.nature.com/articles/s41598-017-14583-7

2

https://www.researchgate.net/publication/325182879_A_review_of_gap-surface_plasmon_metasurfaces_Fundamentals_and_applications

metasurfaces have attracted progressively increasing attention due to their planar configurations, ease of fabrication, and unprecedented capabilities in manipulating the reflected fields that enable integrating diverse bulk-optic-based optical components into a single ultrathin flat element.

1

https://www.osapublishing.org/prj/fulltext.cfm?uri=prj-8-5-707&id=431232

Surface magnon polaritons
Surface magnon polaritons (SMPs) are a type of quasiparticle  in condensed matter physics. They arise from the coupling of incident electromagnetic radiations to the magnetic dipole polarization in the surface layers of a solid. They are analogous to other forms of polaritons such as, plasmons and  phonons but represent an oscillation of the magnetic field in the solid rather than its electric field or mechanical structure.

They are sometimes referred to as magnetic surface polaritons (MSPs).

By employing, artificially constructed metamaterials, whose properties mainly stem from their engineered  internal  fine  structures rather than their bulk physical make up, it is possible to more easily achieve useful SMPs.

Magnons offer a way to  control light to matter interactions at Terahertz frequencies.

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Yttrium iron garnet (YIG, Y3Fe5O12) is a magnetic insulator

Chladni figures
Chladnian figures are patterns that arise on a thin plate (preferentially made of metal ) sprinkled with fine powder when it is set in vibrating motion. This can be done by brushing one edge of the plate with a violin bow, touching it with the base of a vibrating tuning fork or using an electric actuator powered by an electronic oscillator..

As a result of natural resonance, the plate begins to vibrate in one of its modes. The powder is literally thrown away by the vibrating parts when the plate is rung and moves to the places where no or weaker vibration occurs. In this way, the nodal lines of the standing waves that form on the plate become visible. The nodal lines are regions where the plate is not vibrating because the wavelength of the vibrating waves in the plate cancel each other out. A plate possesses several patterns of lines and shapes  based on its many modes of vibration, each with their own frequency. The pattern that forms is determined by the plates shape and dimensions, its thickness, the material from which it is made, as well as the frequency at which the vibration is being forced and the location of the plate's supports.

Origin of the name
Chladnian sound figures are named after French scientist Ernst Florens Friedrich Chladni, who in 1787 published his text Discoveries on the theory of sound , in which he depicted sound figures and describes how they can be produced.

People were so fascinated by the patterns that Chladni was able to earn his living by acting as a teacher and speaker about his characters and even Napoleon said: "This man lets the tones see."

History
Pioneering experiments were performed by Robert Hooke who, on July 8, 1680, had observed the nodal patterns associated with the vibrations of glass plates. Hooke ran a violin bow along the edge of a plate covered with flour and saw the nodal patterns emerge.

Chladni's technique, was first published in 1787 in his book Entdeckungen über die Theorie des Klanges ("Discoveries in the Theory of Sound"). It consisted of drawing a bow over a piece of metal whose surface was lightly covered with sand. The plate was bowed until it reached resonance, when the vibration causes the sand to move and concentrate along the nodal lines where the surface is still, outlining the nodal lines. The patterns formed by these lines are what are now called Chladni figures. Similar nodal patterns can also be found by assembling microscale materials on Faraday waves.

After his discovery Chladni made the sound figures widely known while traveling and lecturing around Europe around 1800. Mathematicians then tried to describe the vibrations of elastic thin plates. Mathematical modelling began around 1811 and 1815 by Sophie Germain with incorrect boundary conditions, Charles Wheatstone in 1833, Gustav Kirchhoff in 1850, Woldemar Voigt in 1893, Lord Rayleigh in 1894, Walter Ritz in 1909 , among others, took part in the development of a theory.

Tonograph
Building on these findings, the American scholar Henry Holbrook Curtis constructed the tonograph with which these sound patterns could be recorded photographically. The apparatus consisted of a metal tube that was bent upwards like a horn and carried a bell at the top on which a membrane was stretched. A fine mixture of salt and emery was applied to this and spread out evenly in the size of a piece of crown. When sounds were sung into the tube, the powdery mixture formed the chladnian figures, which were captured using photographic technology.

In a broadcast from the J. Fischer patent office in Vienna in 1897, it was stated: "The pictures can serve as models for singing exercises which the student who sings into a similarly designed apparatus must strive to achieve by bringing the same tone."

Application
Musical instrument makers have used this method to design the shape of an instrument. For example, a plate in the shape of a guitar or violin top is excited by a loudspeaker that is connected to a frequency generator. The plate must swing freely.

Resonant oscillation of structures is of interest in many branches of engineering. Uncontrolled resonance can make machines very noisy and structures may become unsafe.

Mathematical model
Vibrating plates can be described according to Kirchhoff's plate theory with a biharmonic oscillation equation. In contrast to the d'Alembert operator, the Laplace operator is used twice. The natural vibrations or modes of the plate can be calculated by reducing the time. The following shows the partial differential equation of free oscillation, i.e. without excitation:

Here is the material density the thickness of the plate the flexural strength of the plate. Since this differential equation is not yet sufficient in relation to a physical solution, the boundary conditions must be chosen correctly. Sophie Germain had also presented an equation of this form, but failed to establish the right boundary conditions.

Literatur zur Theorie

 * Martin Gander, Gerhard Wanner: From Euler, Ritz and Galerkin to modern computing. SIAM Review, Vol 54 (4), 2012
 * Karl-Eugen Kurrer: The History of the Theory of Structures. Searching for Equilibrium. Berlin: Ernst & Sohn 2018, S. 703ff., ISBN 978-3-433-03229-9.

Weblinks

 * From Euler, Ritz, and Galerkinto Modern Computing
 * Töne für's Auge...? oder die Klangfiguren des E.F.F. Chladni
 * Chladni Figures and Vibrating Plates - engl. -Java-Applet
 * Eigenschwingungsformen von runden Platten
 * Größere Bilder von Klangfiguren und Versuchsaufbau der Universität Ulm
 * Beitrag zu den Versuchen über die Klangfiguren schwingender Fläche.
 * Entdeckungen über die Theorie des Klanges, MPIWG Library Collection
 * Entdeckungen über die Theorie des Klanges, MPIWG Library Collection

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Extropy
The term extropy is a proposed measure of a system's intelligence, sentience, knowledge, adaptability, power, aliveness, vitality, diversity, complexity and capacity for growth. The more a system possesses these attributes the higher its extropy.

Extropy measures information rich order, that is the order in a system which is structured by embedded information about conditions outside the system. The similar term entropy also measures order and takes on a lower value as a system becomes more ordered, however if has difficulty in representing the nature of the order. Thus a crystal structure is highly ordered but contains no embedded information. A DNA molecule has structure and also information coded within it.

Extropy is also loosely used as the antonym of entropy, because it increases as things become more ordered and decreases as they become chaotic which is the inverse of  entropy. Systems with a high extropy have a low entropy because they are highly ordered. But conversely systems with a low entropy may not have a very high extropy because although they are ordered, that order does not contain information about the systems surroundings.

For example nucleic acid s in solution have less extropy than those stored separately in test tubes and less still than those that form part of a DNA molecule that describes a viable organism.

The word was coined by Tom Bell (T.O. Morrow) and defined by Max More in January 1988 as:-

"'the extent of a living or organizational system's intelligence, functional order, vitality, energy, life,experience, and capacity and drive for improvement and growth.'"""

It is a measure of intelligence, its knowledge, power, life, vitality, diversity, complexity and capacity for growth. It is the opposite of entropy. This concept was developed TO Morrow (real name Tom Bell) in January 1988. The concept was elaborated extropista Max More. Extropisti claim to spontaneous order, which in their opinion is promoting decentralized and voluntary processes of governance, the promotion of tolerance, free market, diversity of thinking long-term view, personal responsibility and freedom.

Extropy expresses a metaphor, rather than serving as a technical term, and so is not simply the opposite of entropy, although it is also considered the appropriate antonym

Extropy is donated an uppercase Greek letter Pi thus Π. The change in extropy is more interesting than its absolute value.

From Fossils to Astrobiology : Records of Life on Earth and the Search for Extraterrestrial Biosignatures. edited by Joseph Seckbach, Maud Walsh, 2009, page 376

Extropy has its law, too. It was first formulated by Edward Harrison:“Hydrogen is a light, odorless gas, which, given enough time, turns into people.”Just make it a tiny bit more general and update the terminology, and you get:“Large enough systems tend to form subsystems in which extropy grows.”

Extropianism
One who seeks to overcome human limits, live indefinitely long, become more intelligence, and more self-creating. A transhumanist who affirms the values and attitudes codified and expressed in The Extropian Principles. [Max More, 1988] http://www.extropy.org/neologo.htm#e

Use in Popular culture
The rock band CHAOTROPE titled a song Extropy/Entropy.