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Analysis
Economics
Economics Agroecosystem analysis Input–output model if applied to a region, is called Regional Impact Multiplier System
Analysis
Government
Government
Analysis
Intelligence
Intelligence The field of intelligence employs analysts to break down and understand a wide array of questions. Intelligence agencies may use heuristics, inductive and deductive reasoning, social network analysis, dynamic network analysis, link analysis, and brainstorming to sort through problems they face. Military i...
Analysis
Policy
Policy Policy analysis – The use of statistical data to predict the effects of policy decisions made by governments and agencies Policy analysis includes a systematic process to find the most efficient and effective option to address the current situation. Qualitative analysis – The use of anecdotal evidence to pre...
Analysis
Humanities and social sciences
Humanities and social sciences
Analysis
Linguistics
Linguistics Linguistics explores individual languages and language in general. It breaks language down and analyses its component parts: theory, sounds and their meaning, utterance usage, word origins, the history of words, the meaning of words and word combinations, sentence construction, basic construction beyond th...
Analysis
Literature
Literature Literary criticism is the analysis of literature. The focus can be as diverse as the analysis of Homer or Freud. While not all literary-critical methods are primarily analytical in nature, the main approach to the teaching of literature in the west since the mid-twentieth century, literary formal analysis or...
Analysis
Music
Music Musical analysis – a process attempting to answer the question "How does this music work?" Musical Analysis is a study of how the composers use the notes together to compose music. Those studying music will find differences with each composer's musical analysis, which differs depending on the culture and history...
Analysis
Philosophy
Philosophy Philosophical analysis – a general term for the techniques used by philosophers Philosophical analysis refers to the clarification and composition of words put together and the entailed meaning behind them. Philosophical analysis dives deeper into the meaning of words and seeks to clarify that meaning by co...
Analysis
Other
Other Aura analysis – a pseudoscientific technique in which supporters of the method claim that the body's aura, or energy field is analysed Bowling analysis – Analysis of the performance of cricket players Lithic analysis – the analysis of stone tools using basic scientific techniques Lithic analysis is most ofte...
Analysis
See also
See also Formal analysis Metabolism in biology Methodology Scientific method Synthesis (disambiguation) – list of terms related to synthesis, the converse of analysis
Analysis
References
References
Analysis
External links
External links Category:Abstraction Category:Critical thinking skills Category:Emergence Category:Empiricism Category:Epistemological theories Category:Intelligence Category:Mathematical modeling Category:Metaphysics of mind Category:Methodology Category:Ontology Category:Philosophy of logic Category:Rationalism Cat...
Analysis
Table of Content
Short description, Science and technology, Chemistry, Types of Analysis, Isotopes, Computer science, Engineering, Mathematics, Psychotherapy, Signal processing, Statistics, Business, Economics, Government, Intelligence, Policy, Humanities and social sciences, Linguistics, Literature, Music, Philosophy, Other, See also,...
Abner Doubleday
short description
Abner Doubleday (June 26, 1819 – January 26, 1893) was a career United States Army officer and Union major general in the American Civil War. He fired the first shot in defense of Fort Sumter, the opening battle of the war, and had a pivotal role in the early fighting at the Battle of Gettysburg. Gettysburg was his fin...
Abner Doubleday
Early years
Early years Doubleday, the son of Ulysses F. Doubleday and Hester Donnelly, was born in Ballston Spa, New York, in a small house on the corner of Washington and Fenwick streets. As a child, Abner was very short. The family all slept in the attic loft of the one-room house. His paternal grandfather, also named Abner, ha...
Abner Doubleday
Early commands and Fort Sumter
Early commands and Fort Sumter thumb|Major Robert Anderson and his officers at Fort Sumter, South Carolina 200px|right|thumb|Doubleday photo displayed at Fort Sumter National Monument in Charleston harbor thumb|200px|Fort Sumter Medal bearing the likeness of Major Robert Anderson which was presented to Abner Doubleday...
Abner Doubleday
Brigade and division command in Virginia
Brigade and division command in Virginia Doubleday was promoted to major on May 14, 1861, and commanded the Artillery Department in the Shenandoah Valley from June to August, and then the artillery for Major General Nathaniel Banks's division of the Army of the Potomac. He was appointed brigadier general of volunteers ...
Abner Doubleday
Gettysburg
Gettysburg thumb|Birthplace in Ballston Spa thumb|right|Doubleday and his wife, Mary At the start of the Battle of Gettysburg, July 1, 1863, Doubleday's division was the second infantry division on the field to reinforce the cavalry division of Brigadier General John Buford. When his corps commander, Major General John...
Abner Doubleday
Washington
Washington Doubleday assumed administrative duties in the defenses of Washington, D.C., where he was in charge of courts martial, which gave him legal experience that he used after the war. His only return to combat was directing a portion of the defenses against the attack by Confederate Lieutenant General Jubal A. Ea...
Abner Doubleday
Postbellum career
Postbellum career After the Civil War, Doubleday mustered out of the volunteer service on August 24, 1865, reverted to the rank of lieutenant colonel, and became the colonel of the 35th U.S. Infantry in September 1867. He was stationed in San Francisco from 1869 through 1871 and he took out a patent for the cable car r...
Abner Doubleday
Theosophy
Theosophy In the summer of 1878, Doubleday lived in Mendham Township, New Jersey, and became a prominent member of the Theosophical Society. When two of the founders of that society, Helena Blavatsky and Henry Steel Olcott, moved to India at the end of that year, he was constituted as the president of the American body...
Abner Doubleday
Death
Death thumb|right|Doubleday's tombstone in Arlington National Cemetery Doubleday died of heart disease in Mendham Township on January 26, 1893. Doubleday's body was laid in state in New York's City Hall and then was taken to Washington by train from Mendham, and was buried in Arlington National Cemetery in Arlington Co...
Abner Doubleday
Baseball
Baseball Although Doubleday achieved minor fame as a competent combat general with experience in many important Civil War battles, he is more widely known as the supposed inventor of the game of baseball, in Elihu Phinney's cow pasture in Cooperstown, New York, in 1839. The Mills Commission, chaired by Abraham G. Mil...
Abner Doubleday
Namesakes and honors
Namesakes and honors thumb|right|Abner Doubleday monument in Ballston Spa Doubleday's men, admirers, and the state of New York erected a monument to him at Gettysburg. There is a obelisk monument at Arlington National Cemetery where he is buried. Doubleday Field is a 9,791-seat baseball stadium named for Abner Double...
Abner Doubleday
See also
See also List of American Civil War generals (Union) William Webb Ellis, sometimes apocryphally credited with inventing rugby football
Abner Doubleday
Notes
Notes
Abner Doubleday
References
References Gomes, Michael. "Abner Doubleday and Theosophy in America: 1879–1884". Sunrise, April/May 1991. "Doubleday, Abner" in The Handbook of Texas.
Abner Doubleday
Further reading
Further reading Silkenat, David. Raising the White Flag: How Surrender Defined the American Civil War. Chapel Hill: University of North Carolina Press, 2019. .
Abner Doubleday
External links
External links Defense of Madame Blavatsky Baseball Hall of Fame Photo of Abner Doubleday and wife Mary, taken by Mathew Brady, owned by University of Michigan Museum of Art Ulysses Freeman Doubleday – McLean County Museum of History Category:1819 births Category:1893 deaths Category:American military perso...
Abner Doubleday
Table of Content
short description, Early years, Early commands and Fort Sumter, Brigade and division command in Virginia, Gettysburg, Washington, Postbellum career, Theosophy, Death, Baseball, Namesakes and honors, See also, Notes, References, Further reading, External links
America's National Game
short description
right|thumb America's National Game is a book by Albert Spalding, published in 1911, that details the early history of the sport of baseball. It is one of the defining books in the early formative years of modern baseball. Much of the story is told first-hand; since the 1850s, Spalding had been involved in the game, f...
America's National Game
See also
See also History of baseball
America's National Game
References
References Category:1911 non-fiction books Category:Baseball books
America's National Game
Table of Content
short description, See also, References
Amplitude modulation
short description
thumb|right|250px|An audio signal (top) carried by a carrier signal using amplitude modulation (middle) and frequency modulation (bottom).|alt=Animation of audio, AM and FM modulated carriers. Amplitude modulation (AM) is a modulation technique used in electronic communication, most commonly for transmitting messages...
Amplitude modulation
Foundation
Foundation In electronics, telecommunications and mechanics, modulation means varying some aspect of a continuous wave carrier signal with an information-bearing modulation waveform, such as an audio signal which represents sound, or a video signal which represents images. In this sense, the carrier wave, which has a...
Amplitude modulation
Shift keying
Shift keying A simple form of digital amplitude modulation which can be used for transmitting binary data is on–off keying, the simplest form of amplitude-shift keying, in which ones and zeros are represented by the presence or absence of a carrier. On–off keying is likewise used by radio amateurs to transmit Morse c...
Amplitude modulation
Analog telephony
Analog telephony A simple form of amplitude modulation is the transmission of speech signals from a traditional analog telephone set using a common battery local loop.AT&T, Engineering and Operations in the Bell System (1984) p.211 The direct current provided by the central office battery is a carrier with a frequenc...
Amplitude modulation
Amplitude reference
Amplitude reference An additional function provided by the carrier in standard AM, but which is lost in either single or double-sideband suppressed-carrier transmission, is that it provides an amplitude reference. In the receiver, the automatic gain control (AGC) responds to the carrier so that the reproduced audio l...
Amplitude modulation
ITU type designations
ITU type designations In 1982, the International Telecommunication Union (ITU) designated the types of amplitude modulation: DesignationDescriptionA3Edouble-sideband a full-carrier – the basic amplitude modulation schemeR3Esingle-sideband reduced-carrierH3Esingle-sideband full-carrierJ3Esingle-sideband suppressed-carri...
Amplitude modulation
History
History thumb|One of the crude pre-vacuum tube AM transmitters, a Telefunken arc transmitter from 1906. The carrier wave is generated by 6 electric arcs in the vertical tubes, connected to a tuned circuit. Modulation is done by the large carbon microphone (cone shape) in the antenna lead. thumb|One of the first vacuum...
Amplitude modulation
Continuous waves
Continuous waves The first AM transmission was made by Canadian-born American researcher Reginald Fessenden on December 23, 1900 using a spark gap transmitter with a specially designed high frequency 10 kHz interrupter, over a distance of at Cobb Island, Maryland, US. His first transmitted words were, "Hello. One, two...
Amplitude modulation
Early technologies
Early technologies Early experiments in AM radio transmission, conducted by Fessenden, Valdemar Poulsen, Ernst Ruhmer, Quirino Majorana, Charles Herrold, and Lee de Forest, were hampered by the lack of a technology for amplification. The first practical continuous wave AM transmitters were based on either the huge, exp...
Amplitude modulation
Vacuum tubes
Vacuum tubes The 1912 discovery of the amplifying ability of the Audion tube, invented in 1906 by Lee de Forest, solved these problems. The vacuum tube feedback oscillator, invented in 1912 by Edwin Armstrong and Alexander Meissner, was a cheap source of continuous waves and could be easily modulated to make an AM tran...
Amplitude modulation
Single-sideband
Single-sideband In 1915, John Renshaw Carson formulated the first mathematical description of amplitude modulation, showing that a signal and carrier frequency combined in a nonlinear device creates a sideband on both sides of the carrier frequency. Passing the modulated signal through another nonlinear device can extr...
Amplitude modulation
Analysis
Analysis thumb|391x391px|Illustration of amplitude modulation The carrier wave (sine wave) of frequency fc and amplitude A is expressed by . The message signal, such as an audio signal that is used for modulating the carrier, is m(t), and has a frequency fm, much lower than fc: , where m is the amplitude sensitivit...
Amplitude modulation
Spectrum
Spectrum thumb|400px|Figure 2: Double-sided spectra of baseband and AM signals.|alt=Diagrams of an AM signal, with formulas A useful modulation signal m(t) is usually more complex than a single sine wave, as treated above. However, by the principle of Fourier decomposition, m(t) can be expressed as the sum of a set of ...
Amplitude modulation
Power and spectrum efficiency
Power and spectrum efficiency The RF bandwidth of an AM transmission (refer to figure 2, but only considering positive frequencies) is twice the bandwidth of the modulating (or "baseband") signal, since the upper and lower sidebands around the carrier frequency each have a bandwidth as wide as the highest modulating fr...
Amplitude modulation
Modulation index
Modulation index The AM modulation index is a measure based on the ratio of the modulation excursions of the RF signal to the level of the unmodulated carrier. It is thus defined as: where and are the modulation amplitude and carrier amplitude, respectively; the modulation amplitude is the peak (positive or negative...
Amplitude modulation
{{anchor
Modulation methods 300px|right|thumb|Anode (plate) modulation. A tetrode's plate and screen grid voltage is modulated via an audio transformer. The resistor R1 sets the grid bias; both the input and output are tuned circuits with inductive coupling. Modulation circuit designs may be classified as low- or high-level (d...
Amplitude modulation
Low-level generation
Low-level generation In modern radio systems, modulated signals are generated via digital signal processing (DSP). With DSP many types of AM are possible with software control (including DSB with carrier, SSB suppressed-carrier and independent sideband, or ISB). Calculated digital samples are converted to voltages with...
Amplitude modulation
High-level generation
High-level generation High-power AM transmitters (such as those used for AM broadcasting) are based on high-efficiency class-D and class-E power amplifier stages, modulated by varying the supply voltage. Older designs (for broadcast and amateur radio) also generate AM by controlling the gain of the transmitter's final...
Amplitude modulation
{{anchor
Demodulation methods The simplest form of AM demodulator consists of a diode which is configured to act as envelope detector. Another type of demodulator, the product detector, can provide better-quality demodulation with additional circuit complexity.
Amplitude modulation
See also
See also Airband AM stereo Amplitude modulation signalling system (AMSS) Double-sideband suppressed-carrier transmission (DSB-SC) Modulation sphere Shortwave radio Types of radio emissions
Amplitude modulation
References
References
Amplitude modulation
Bibliography
Bibliography Newkirk, David and Karlquist, Rick (2004). Mixers, modulators and demodulators. In D. G. Reed (ed.), The ARRL Handbook for Radio Communications (81st ed.), pp. 15.1–15.36. Newington: ARRL. .
Amplitude modulation
External links
External links Amplitude Modulation by Jakub Serych, Wolfram Demonstrations Project. Amplitude Modulation, by S Sastry. Amplitude Modulation, an introduction by Federation of American Scientists. Amplitude Modulation tutorial including related topics of modulators, demodulators, etc... Analog Modulation online int...
Amplitude modulation
Table of Content
short description, Foundation, Shift keying, Analog telephony, Amplitude reference, ITU type designations, History, Continuous waves, Early technologies, Vacuum tubes, Single-sideband, Analysis, Spectrum, Power and spectrum efficiency, Modulation index, {{anchor, Low-level generation, High-level generation, {{anchor, S...
Augustin-Jean Fresnel
Short description
Augustin-Jean Fresnel (10 May 1788 – 14 July 1827) was a French civil engineer and physicist whose research in optics led to the almost unanimous acceptance of the wave theory of light, excluding any remnant of Newton's corpuscular theory, from the late 1830sDarrigol, 2012, pp. 220–223. until the end of the 19th centur...
Augustin-Jean Fresnel
Early life
Early life thumb|Monument to Augustin Fresnel on the facade of his birthplace at 2 Rue Augustin Fresnel, Broglie (facing Rue Jean François Mérimée), inaugurated on 14 September 1884. The inscription, when translated, says:"Augustin Fresnel, engineer of Bridges and Roads, member of the Academy of Sciences, creator of...
Augustin-Jean Fresnel
Family
Family Augustin-Jean Fresnel (also called Augustin Jean or simply Augustin), born in Broglie, Normandy, on 10 May 1788, was the second of four sons of the architect Jacques Fresnel and his wife Augustine, née Mérimée. The family moved twice—in 1789/90 to Cherbourg,Levitt (2013, p. 23) says "in 1790". Silliman (1967,...
Augustin-Jean Fresnel
Education
Education The Fresnel brothers were initially home-schooled by their mother. The sickly Augustin was considered the slow one, not inclined to memorization;Levitt, 2013, pp. 24–25; Buchwald, 1989, p. 111. but the popular story that he hardly began to read until the age of eight is disputed.That age was given by Arago...
Augustin-Jean Fresnel
Religious formation
Religious formation Fresnel's parents were Roman Catholics of the Jansenist sect, characterized by an extreme Augustinian view of original sin. Religion took first place in the boys' home-schooling. In 1802, his mother said: Augustin remained a Jansenist.Levitt, 2013, p. 24. He regarded his intellectual talents as g...
Augustin-Jean Fresnel
Engineering assignments
Engineering assignments Fresnel was initially posted to the western département of Vendée. There, in 1811, he anticipated what became known as the Solvay process for producing soda ash, except that recycling of the ammonia was not considered. That difference may explain why leading chemists, who learned of his disco...
Augustin-Jean Fresnel
Contributions to physical optics
Contributions to physical optics
Augustin-Jean Fresnel
Historical context: From Newton to Biot
Historical context: From Newton to Biot The appreciation of Fresnel's reconstruction of physical optics might be assisted by an overview of the fragmented state in which he found the subject. In this subsection, optical phenomena that were unexplained or whose explanations were disputed are named in bold type. thum...
Augustin-Jean Fresnel
Rêveries
Rêveries thumb|Bas-relief of Fresnel's uncle Léonor Mérimée (1757–1836), on the same wall as the Fresnel monument in Broglie Fresnel's letters from later in 1814 reveal his interest in the wave theory, including his awareness that it explained the constancy of the speed of light and was at least compatible with stel...
Augustin-Jean Fresnel
Diffraction
Diffraction
Augustin-Jean Fresnel
First attempt (1815)
First attempt (1815) On 12 July 1815, as Fresnel was about to leave Paris, Arago left him a note on a new topic: Fresnel would not have ready access to these works outside Paris, and could not read English.Fresnel, 1866–70, vol. 1, pp. 6–7. But, in Mathieu—with a point-source of light made by focusing sunlight with...
Augustin-Jean Fresnel
"Efficacious ray", double-mirror experiment (1816)
"Efficacious ray", double-mirror experiment (1816) thumb|307px|Replica of Young's two-source interference diagram (1807), with sources A and B producing minima at C, D, E, and FCf. Young, 1807, vol. 1, p. 777 & Fig. 267. thumb|307px|Fresnel's double mirror (1816). The mirror segments M1 and M2 produce virtual image...
Augustin-Jean Fresnel
Prize memoir (1818) and sequel
Prize memoir (1818) and sequel On 17 March 1817, the Académie des Sciences announced that diffraction would be the topic for the biannual physics Grand Prix to be awarded in 1819.Kipnis, 1991, p. 218; Buchwald, 2013, p. 453; Levitt, 2013, p. 44.  Frankel (1976, pp. 160–161) and Grattan-Guinness (1990, p. 867) note t...
Augustin-Jean Fresnel
Polarization
Polarization
Augustin-Jean Fresnel
Background: Emissionism and selectionism
Background: Emissionism and selectionism An emission theory of light was one that regarded the propagation of light as the transport of some kind of matter. While the corpuscular theory was obviously an emission theory, the converse did not follow: in principle, one could be an emissionist without being a corpuscula...
Augustin-Jean Fresnel
Interference of polarized light, chromatic polarization (1816–21)
Interference of polarized light, chromatic polarization (1816–21) In July or August 1816, Fresnel discovered that when a birefringent crystal produced two images of a single slit, he could not obtain the usual two-slit interference pattern, even if he compensated for the different propagation times. A more general e...
Augustin-Jean Fresnel
Breakthrough: Pure transverse waves (1821)
Breakthrough: Pure transverse waves (1821) thumb|André-Marie Ampère (1775–1836) In the draft memoir of 30 August 1816, Fresnel mentioned two hypotheses—one of which he attributed to Ampère—by which the non-interference of orthogonally-polarized beams could be explained if polarized light waves were partly transvers...
Augustin-Jean Fresnel
Partial reflection (1821)
Partial reflection (1821) In the second installment of "Calcul des teintes" (June 1821), Fresnel supposed, by analogy with sound waves, that the density of the aether in a refractive medium was inversely proportional to the square of the wave velocity, and therefore directly proportional to the square of the refract...
Augustin-Jean Fresnel
Circular and elliptical polarization, optical rotation (1822)
Circular and elliptical polarization, optical rotation (1822) thumb|305px|A right-handed/clockwise circularly polarized wave as defined from the point of view of the source. It would be considered left-handed/anti-clockwise circularly polarized if defined from the point of view of the receiver. If the rotating vecto...
Augustin-Jean Fresnel
Total internal reflection (1817–23)
Total internal reflection (1817–23) thumb|305px|Cross-section of a Fresnel rhomb (blue) with graphs showing the p component of vibration (parallel to the plane of incidence) on the vertical axis, vs. the s component (square to the plane of incidence and parallel to the surface) on the horizontal axis. If the incomin...
Augustin-Jean Fresnel
Double refraction
Double refraction
Augustin-Jean Fresnel
Background: Uniaxial and biaxial crystals; Biot's laws
Background: Uniaxial and biaxial crystals; Biot's laws When light passes through a slice of calcite cut perpendicular to its optic axis, the difference between the propagation times of the ordinary and extraordinary waves has a second-order dependence on the angle of incidence. If the slice is observed in a highly c...
Augustin-Jean Fresnel
First memoir and supplements (1821–22)
First memoir and supplements (1821–22) Until Fresnel turned his attention to biaxial birefringence, it was assumed that one of the two refractions was ordinary, even in biaxial crystals.Buchwald, 1989, p. 260. But, in a memoir submittedIn Fresnel's collected works (1866–70), a paper is said to have been "presented" ...
Augustin-Jean Fresnel
Second memoir (1822–26)
Second memoir (1822–26) Having presented the pieces of his theory in roughly the order of discovery, Fresnel needed to rearrange the material so as to emphasize the mechanical foundations;Grattan-Guinness, 1990, pp. 896–897.  Silliman, 1967, pp. 262–263; 2008, p.170 and he still needed a rigorous treatment of Biot's...
Augustin-Jean Fresnel
Photoelasticity, multiple-prism experiments (1822)
Photoelasticity, multiple-prism experiments (1822) thumb|Chromatic polarization in a plastic protractor, caused by stress-induced birefringence. In 1815, Brewster reported that colors appear when a slice of isotropic material, placed between crossed polarizers, is mechanically stressed. Brewster himself immediately...
Augustin-Jean Fresnel
Reception
Reception For the supplement to Riffault's translation of Thomson's System of Chemistry, Fresnel was chosen to contribute the article on light. The resulting 137-page essay, titled De la Lumière (On Light),Fresnel, 1822a. was apparently finished in June 1821 and published by February 1822.Grattan-Guinness, 1990, p. ...
Augustin-Jean Fresnel
Lighthouses and the Fresnel lens
Lighthouses and the Fresnel lens Fresnel was not the first person to focus a lighthouse beam using a lens. That distinction apparently belongs to the London glass-cutter Thomas Rogers, whose first lenses, 53cm in diameter and 14cm thick at the center, were installed at the Old Lower Lighthouse at Portland Bill in 17...
Augustin-Jean Fresnel
Honors
Honors thumb|Bust of Augustin Fresnel by David d'Angers (1854), formerly at the lighthouse of Hourtin, Gironde, and now exhibited at the Fresnel was elected to the Société Philomathique de Paris in April 1819,Kipnis, 1991, p. 217. and in 1822 became one of the editors of the Société's Bulletin des Sciences.Frankel...
Augustin-Jean Fresnel
Decline and death
Decline and death thumb|upright|Fresnel's grave at Père Lachaise Cemetery, Paris, photographed in 2018 Fresnel's health, which had always been poor, deteriorated in the winter of 1822–1823, increasing the urgency of his original research, and (in part) preventing him from contributing an article on polarization and ...
Augustin-Jean Fresnel
Posthumous publications
Posthumous publications thumb|upright|Émile Verdet (1824–1866) Fresnel's "second memoir" on double refraction was not printed until late 1827, a few months after his death.Fresnel, 1866–70, vol. 2, p. 800n. Until then, the best published source on his work on double refraction was an extract of that memoir, printed...
Augustin-Jean Fresnel
Lost works
Lost works Fresnel's essay Rêveries of 1814 has not survived.Buchwald, 1989, p. 116. The article "Sur les Différents Systèmes relatifs à la Théorie de la Lumière" ("On the Different Systems relating to the Theory of Light"), which Fresnel wrote for the newly launched English journal European Review,Fresnel, 1866–70,...
Augustin-Jean Fresnel
Unfinished work
Unfinished work
Augustin-Jean Fresnel
Aether drag and aether density
Aether drag and aether density In 1810, Arago found experimentally that the degree of refraction of starlight does not depend on the direction of the earth's motion relative to the line of sight. In 1818, Fresnel showed that this result could be explained by the wave theory,Cf. Darrigol, 2012, pp. 258–260. on the hy...
Augustin-Jean Fresnel
Dispersion
Dispersion The analogy between light waves and transverse waves in elastic solids does not predict dispersion—that is, the frequency-dependence of the speed of propagation, which enables prisms to produce spectra and causes lenses to suffer from chromatic aberration. Fresnel, in De la Lumière and in the second suppl...
Augustin-Jean Fresnel
Conical refraction
Conical refraction The analytical complexity of Fresnel's derivation of the ray-velocity surface was an implicit challenge to find a shorter path to the result. This was answered by MacCullagh in 1830, and by William Rowan Hamilton in 1832.Lloyd, 1834, pp. 387–388.
Augustin-Jean Fresnel
Legacy
Legacy thumb|The lantern room of the Cordouan Lighthouse, in which the first Fresnel lens entered service in 1823. The current fixed catadioptric "beehive" lens replaced Fresnel's original rotating lens in 1854. Within a century of Fresnel's initial stepped-lens proposal, more than 10,000 lights with Fresnel lenses...
Augustin-Jean Fresnel
See also
See also
Augustin-Jean Fresnel
Explanatory notes
Explanatory notes
Augustin-Jean Fresnel
References
References
Augustin-Jean Fresnel
Citations
Citations
Augustin-Jean Fresnel
General and cited references
General and cited references D.F.J. Arago (tr. B. Powell), 1857, "Fresnel" (elegy read at the Public Meeting of the Academy of Sciences, 26 July 1830), in D.F.J. Arago (tr.  W.H. Smyth, B. Powell, and R. Grant), Biographies of Distinguished Scientific Men (single-volume edition), London: Longman, Brown, Green, Long...