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Electromagnetic Radiation

In physics, electromagnetic radiation (EM radiation or EMR) refers to the waves (or their quanta, photons) of the electromagnetic field, propagating (radiating) through space, carrying electromagnetic radiant energy.[1] It includes radio waves, microwaves, infrared, (visible) light, ultraviolet, X-rays, and gamma rays.[2] Classically, electromagnetic radiation consists of electromagnetic waves, which are synchronized oscillations of electric and magnetic fields. In a vacuum, electromagnetic waves travel at the speed of light, commonly denoted c. In homogeneous, isotropic media, the oscillations of the two fields are perpendicular to each other and perpendicular to the direction of energy and wave propagation, forming a transverse wave. The wavefront of electromagnetic waves emitted from a point source (such as a light bulb) is a sphere
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Apollonius Of Perga
Apollonius of Perga (Greek: Ἀπολλώνιος ὁ Περγαῖος; Latin: Apollonius Pergaeus; c.240 BC – c.190 BC) was an Ancient Greek geometer and astronomer known for his work on conic sections. Beginning from the contributions of Euclid and Archimedes on the topic, he brought them to the state prior to the invention of analytic geometry. His definitions of the terms ellipse, parabola, and hyperbola are the ones in use today. Apollonius worked on numerous other topics, including astronomy. Most of this work has not survived, where exceptions are typically fragments referenced by other authors
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Pappus Of Alexandria

Pappus of Alexandria (/ˈpæpəs/; Greek: Πάππος ὁ Ἀλεξανδρεύς; c.  290 – c.  350 AD) was one of the last great Greek mathematicians of antiquity, known for his Synagoge (Συναγωγή) or Collection (c.  340), and for Pappus's hexagon theorem in projective geometry. Nothing is known of his life, other than what can be found in his own writings: that he had a son named Hermodorus, and was a teacher in Alexandria.[1] Collection, his best-known work, is a compendium of mathematics in eight volumes, the bulk of which survives
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Isaac Vossius

He was the son of the humanist Gerhard Johann Vossius. Isaak formed what was accounted the best private library in the world (Massil 2003). He had a contemporary reputation for eccentricity, refusing the sacrament on his deathbed, it was reported, until reminded that to do so would reflect unfavorably on the canons of St George's Chapel, Windsor Castle, to which chapter he belonged. He was raised in the atmosphere of a scholarly household, familiar with Greek, ancient geography, and Arabic from an early age
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French Language

The majority of French words derive from Vulgar Latin or were constructed from Latin or Greek roots. In many cases, a single etymological root appears in French in a "popular" or native form, inherited from Vulgar Latin, and a learned form, borrowed later from Classical Latin. The following pairs consist of a native noun and a learned adjective:



Traité De La Lumière
Treatise on Light (French: Traité de la Lumière) is a 1690 book written by the Dutch polymath Christiaan Huygens on his wave theory of light. Huygens' starting point was Descartes' theory, as presented in the Dioptrique, which Huygens aimed to supplant. Huygens' theory is also seen as the historical rival of Newton's theory, which was presented in the Opticks.[1][2][3]

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Huygens–Fresnel Principle
The Huygens–Fresnel principle (named after Dutch physicist Christiaan Huygens and French physicist Augustin-Jean Fresnel) is a method of analysis applied to problems of wave propagation both in the far-field limit and in near-field diffraction and also reflection. It states that every point on a wavefront is itself the source of spherical wavelets, and the secondary wavelets emanating from different points mutually interfere.[1] The sum of these spherical wavelets forms the wavefront. This clarifies the fact that in this context the generalized principle reflects the linearity of quantum mechanics and the fact that the quantum mechanics equations are first order in time. Finally only in this case the superposition principle fully apply, i.e. the wave functThis clarifies the fact that in this context the generalized principle reflects the linearity of quantum mechanics and the fact that the quantum mechanics equations are first order in time
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Anisotropic

Anisotropy (/ˌæn.ə-, ˌæn.ˈsɒtr.əp.i/) is the property of a material which allows it to change or assume different properties in different directions as opposed to isotropy. It can be defined as a difference, when measured along different axes, in a material's physical or mechanical properties (absorbance, refractive index, conductivity, tensile strength, etc.) An example of anisotropy is light coming through a polarizer
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Birefringence
Birefringence is the optical property of a material having a refractive index that depends on the polarization and propagation direction of light.[1] These optically anisotropic materials are said to be birefringent (or birefractive). The birefringence is often quantified as the maximum difference between refractive indices exhibited by the material. Crystals with non-cubic crystal structures are often birefringent, as are plastics under mechanical stress. Birefringence is responsible for the phenomenon of double refraction whereby a ray of light, when incident upon a birefringent material, is split by polarization into two rays taking slightly different paths. This effect was first described by the Danish scientist Rasmus Bartholin in 1669, who observed it[2] in calcite, a crystal having one of the strongest birefringences
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Adequality
Adequality is a technique developed by
Pierre de Fermat in his treatise Methodus ad disquirendam maximam et minimam[1] (a Latin treatise circulated in France c. 1636) to calculate maxima and minima of functions, tangents to curves, area, center of mass, least action, and other problems in calculus. According to André Weil, Fermat "introduces the technical term adaequalitas, adaequare, etc., which he says he has borrowed from Diophantus. As Diophantus V.11 shows, it means an approximate equality, and this is indeed how Fermat explains the word in one of his later writings." (Weil 1973).[2] Diophantus coined the word παρισότης (parisotēs) to refer to an approximate equality.[3] Claude Gaspard Bachet de Méziriac translated Diophantus's Greek word into Latin as adaequalitas.[
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