delta2
/ˈdɛltə/
noun: delta; plural noun: deltas
a triangular tract of sediment deposited at the mouth of a river, typically where it diverges into several outlets.

"the Nile delta"

noun: delta; plural noun: deltas
1.
the fourth letter of the Greek alphabet ( Δ, δ ), transliterated as ‘d’.

BRITISH
a fourth-class mark given for an essay, examination paper, or other piece of work.
the fourth in a series of items, categories, etc.
modifier noun: delta

"delta hepatitis"

D
E
F
EN
D
IN
G

deafening (comparative more deafening, superlative most deafening)

Loud enough to cause temporary or permanent hearing loss.

(hyperbolic) Very loud.

Derived terms
deafening silence

AS HEARING LOSS

A man asked, "What of wisdom? Has this not been plentiful in the world since the days of the Great Enlighteners, of whom Solomon was deemed the greatest?

Even before him, there was much wisdom, yet is Earth a better place for this?

What has it contributed to progress?"

Jesus replied, "Alas, never has there been a shortage of wisdom in the world, but always there has been too little in the hearts of men.

Wisdom is not something written in books, but that, which is conveyed from the book of the heart.

It is a way of life."

A N U M E R O L O G I E N

gien (verbal noun gientyn, past participle giennit)

to generate

Derived terms
aaghien (“to regenerate”)

gien

to declare

to admit, to acknowledge

Etymology

From Late Latin topologia, from Ancient Greek τόπος (tópos, “place, locality”) + -(o)logy (“study of, a branch of knowledge”).

topology (countable and uncountable, plural topologies)

(mathematics, uncountable) The branch of mathematics dealing with those properties of a geometrical object (of arbitrary dimensionality) that are unchanged by continuous deformations (such as stretching, bending, etc., without tearing or gluing).

From Old French géométrie, from Latin geometria, from Ancient Greek γεωμετρία (geōmetría, “geometry, land-survey”), from γεωμέτρης (geōmétrēs, “land measurer”), from γῆ (gê, “earth, land, country”) + -μετρία (-metría, “measurement”), from μέτρον (métron, “a measure”).

Doublet of gematria.

gematria (countable and uncountable, plural gematrias or gematriot)

A cabalistic method of interpreting Hebrew words, based on numerical values of letters.

lettering (countable and uncountable, plural letterings)

Written text, especially when printed.

This use of add up comes from the mid 1900s. It developed from the adding that is done in arithmetic. If numbers add up, they come to the total that is expected; they make sense. If the numbers don't add up, it means the total number doesn't make sense in relation to the separate amounts.

amount
/əˈmaʊnt/

verb
gerund or present participle: amounting
come to be (the total) when added together.

gather
/ˈɡaðə/
verb
gerund or present participle: gathering
1.
come together; assemble or accumulate.

to bring forth

Q4

the 4th quarter of the year...

going full circle

echoed

simple past tense and past participle of echo

encode
/ɪnˈkəʊd,ɛnˈkəʊd/
verb
past tense: encoded; past participle: encoded
convert into a coded form.

an encoding

a message

Middle English: from Old French, based on Latin missus, past participle of mittere ‘send’.

late 15th century (as a verb): alteration of send1 or descend. The noun dates from the early 18th century.

climb to the summit of (a mountain or hill).

"the first traveller to ascend the mountain"

The continental divide passes through the southern end of the range. The Chihuahuan Desert has its northwest extension into the foothills regions of the Pyramid Mountains.

The ascension of The Great Pyramid of Giza

re- +‎ energise

Verb

reenergise (third-person singular simple present reenergises, present participle reenergising, simple past and past participle reenergised)

Alternative form of reenergize

disguise
/dɪsˈɡʌɪz/
verb
give (someone or oneself) a different appearance in order to conceal one's identity.

😎

Etymology
From Middle French invisibilité, from Latin invisibilitas

Noun
invisibility (countable and uncountable, plural invisibilities)

The state of being invisible.
That which is invisible.

invisibilité f (plural invisibilités)

invisibility

Introduction Magnetic levitation or maglev is based on the repulsion of the magnetic field from the dia-magnetic and found its application in various areas such as levitating trains [1], electromagnetic guns [2], medicine, and many others [3]. The superconductors exhibit an example of a perfect diamagnet with 0=μ due to the Meissner effect, and are currently used as building blocks in maglev technology [4].

The ubiquitous problem with the application of the superconductors, however, is the require-ment for low temperatures. While there are no natural materials, exhibiting strong diamagnetic response at room temperature, it has been recently shown that certain metamaterials can be character-ized by effective magnetic permeability eff 0ªμ in a con-siderably wide frequency range [5, 6], and the effect of the magnetic levitation of macroscopic objects over the surface of such metamaterials has been predicted [9]. Generally, the study of electromagnetic forces both at macro- and micro level has become a rapidly growing research area in recent years [7, 8] Metamaterials also allow the realization of the electric counterpart of the super diamagnets, so-called Epsilon-Near-Zero (ENZ) metamaterials, the structures which, analogously to the superconductor, repel the electric field. And it has been shown recently, that an electric dipole can levitate over a surface of such a metamaterial

Acoustic levitation is a method for suspending matter in air against gravity using acoustic radiation pressure from high intensity sound waves. It works on the same principles as acoustic tweezers by harnessing acoustic radiation forces.

noun: elevation
1.
the action or fact of raising or being raised to a higher or more important level, state, or position.

verb: elevate; 3rd person present: elevates; past tense: elevated; past participle: elevated; gerund or present participle: elevating
1.
raise or lift (something) to a higher position

late Middle English: from Latin elevat- ‘raised’, from the verb elevare, from e- (variant of ex- ) ‘out, away’ + levare ‘lighten’ (from levis ‘light’).

🕯

light beam or beam of light is a directional projection of light energy radiating from a light source. Sunlight forms a light beam (a sunbeam) when filtered through media such as clouds, foliage, or windows. To artificially produce a light beam, a lamp and a parabolic reflector is used in many lighting devices such as spotlights, car headlights, PAR Cans, and LED housings. Light from certain types of laser has the smallest possible beam divergence.

In electromagnetics, especially in optics, beam divergence is an angular measure of the increase in beam diameter or radius with distance from the optical aperture or antenna aperture from which the beam emerges. The term is relevant only in the "far field", away from any focus of the beam. Practically speaking, however, the far field can commence physically close to the radiating aperture, depending on aperture diameter and the operating wavelength.

In electromagnetics, especially in optics, beam divergence is an angular measure of the increase in beam diameter or radius with distance from the optical aperture or antenna aperture from which the beam emerges. The term is relevant only in the "far field", away from any focus of the beam. Practically speaking, however, the far field can commence physically close to the radiating aperture, depending on aperture diameter and the operating wavelength.

Like all electromagnetic beams, lasers are subject to divergence, which is measured in milliradians (mrad) or degrees. For many applications, a lower-divergence beam is preferable. Neglecting divergence due to poor beam quality, the divergence of a laser beam is proportional to its wavelength and inversely proportional to the diameter of the beam at its narrowest point. For example, an ultraviolet laser that emits at a wavelength of 308 nm will have a lower divergence than an infrared laser at 808 nm, if both have the same minimum beam diameter. The divergence of good-quality laser beams is modeled using the mathematics of Gaussian beams.

Quantum mechanics was first applied to optics, and interference in particular, by Paul Dirac.[1] Richard Feynman, in his Lectures on Physics, uses Dirac's notation to describe thought experiments on double-slit interference of electrons.[2] Feynman's approach was extended to N-slit interferometers for either single-photon illumination, or narrow-linewidth laser illumination, that is, illumination by indistinguishable photons, by Frank Duarte.[3][4] The N-slit interferometer was first applied in the generation and measurement of complex interference patterns.[3][4]

In this article the generalized N-slit interferometric equation, derived via Dirac's notation, is described. Although originally derived to reproduce and predict N-slit interferograms,[3][4] this equation also has applications to other areas of optics.

Multiple-prism grating laser oscillators,[1] or MPG laser oscillators, use multiple-prism beam expansion to illuminate a diffraction grating mounted either in Littrow configuration or grazing-incidence configuration. Originally, these narrow-linewidth tunable dispersive oscillators were introduced as multiple-prism Littrow (MPL) grating oscillators,[2] or hybrid multiple-prism near-grazing-incidence (HMPGI) grating cavities,[3][4] in organic dye lasers. However, these designs were quickly adopted for other types of lasers such as gas lasers,[5][6] diode lasers,[7][8] and more recently fiber lasers.[9]

The active laser medium (also called gain medium or lasing medium) is the source of optical gain within a laser. The gain results from the stimulated emission of photons through electronic or molecular transitions to a lower energy state from a higher energy state previously populated by a pump source.

Examples of active laser media include:

Certain crystals, typically doped with rare-earth ions (e.g. neodymium, ytterbium, or erbium) or transition metal ions (titanium or chromium); most often yttrium aluminium garnet (Y3Al5O12), yttrium orthovanadate (YVO4), or sapphire (Al2O3);[1] and not often Caesium cadmium bromide (CsCdBr3)
Glasses, e.g. silicate or phosphate glasses, doped with laser-active ions;[2]
Gases, e.g. mixtures of helium and neon (HeNe), nitrogen, argon, carbon monoxide, carbon dioxide, or metal vapors;[3]
Semiconductors, e.g. gallium arsenide (GaAs), indium gallium arsenide (InGaAs), or gallium nitride (GaN).[4]
Liquids, in the form of dye solutions as used in dye lasers.[5][6]

In order to fire a laser, the active gain medium must be in a nonthermal energy distribution known as a population inversion. The preparation of this state requires an external energy source and is known as laser pumping. Pumping may be achieved with electrical currents (e.g. semiconductors, or gases via high-voltage discharges) or with light, generated by discharge lamps or by other lasers (semiconductor lasers). More exotic gain media can be pumped by chemical reactions, nuclear fission,[7] or with high-energy electron beams.[8]