history'' ''the catholic historical review'' ''church history'' ''history religions'' ''journal american academy religion'' ''journal ecclesiastical history'' ''journal religion'' ''journal religious history'' ''journal religion society'' ''journal scientific study religion'' ''methodist history journal'' ''mormon historical studies'' ''numen international review history religions'' ''revue d'histoire eccl siastique'' published english french german ''social compass'' ''sociology religion'' notes bibliography reading eaton mark e religious studies encyclopedism recent history ''the reference librarian'' eliade mircea ioan p couliano ''the harpercollins concise guide world religion


z encyclopedia major religious traditions'' eliade mircea ed ''encyclopedia religion'' vol nd ed vol online gale virtual reference library articles pages experts elliott scott ed ''reinventing religious studies key writings history discipline'' acumen pp fitzgerald timothy ''the ideology religious studies'' oxford university press hart darryl g ''the university gets religion religious studies american higher education'' johns hopkins university press hafner johann relating theology religious studies reflections german academic landscape ''toronto journal


theology'' mccutcheon russell ''the discipline religion structure meaning rhetoric'' routledge martin luther h donald wiebe religious studies scientific discipline persistence delusion ''journal american academy religion'' http digilibphilmunicz bitstream handle digilib religio pdf online miles jack ''god biography'' new york vintage olson carl ''the allure decadent thinking religious studies challenge postmodernism'' oxford university press pals daniel l ''nine theories religion'' rd edition new york oxford university press sharpe eric j ''comparative religion history'' london duckworth


nd revised edition sloan wilson david ''darwin 's cathedral evolution religion nature society'' chicago university chicago press stark rodney ''discovering god origins great religions evolution belief'' new york harpercollins torre ren e de la elo sa mart n religious studies latin america ''annual review sociology'' witte john study law religion united states interim report ''ecclesiastical law journal'' pp external links http ibcsrorg indexphp institute biocultural study religion ibcsr http ibcsrorg indexphpoption com content view category layout blog id itemid ibcsr research review


briefly annotates furnishes online information scholarly articles books related brain behavior culture religion https webarchiveorg web http rrahartsemedu religious research association http wwwsssrweborg society scientific study religion sssr http wwwamericanreligionorg institute study american religion academic societies http wwwaasrorgau australian association study religions aasr http wwwaarweborg american academy religion aar https basracuk british association study religions basr http ccsrca canadian corporation studies religion ccsr http wwweasreu european association study religions easr http wwwiacsrcom international association cognitive science religion iacsr http wwwiahrdk international association


history religions iahr http wwwcsueduau research ipra international philosophy religion association ipra https isasrwordpresscom irish society academic study religions isasr http wwwnzasracnz new zealand association study religions nzasr http wwwnaasrcom north american association study religion naasr https sssreligionorg society scientific study religion sssr http wwweasaonlineorg networks religion indexshtml european association social anthropologists easa anthropology religion online works sources http wwwasuaedu rel introductionhtml studying religion culture university alabama http peopleucalgaryca lipton journalshtml religious studies web guide online journals


mathematics specifically abstract algebra ring theory '''noncommutative ring''' ring whose multiplication commutative exists ''a'' ''b'' ''r'' ''a''''' '''''b'' ''b''''' '''''a'' many authors use term ''noncommutative rings'' refer rings necessarily commutative hence include commutative rings definition '''noncommutative algebra''' study results applying rings required commutative many important results field noncommutative algebra apply commutative rings special cases although authors assume rings

Formal science
Mathematics
Pure mathematics
Algebra
Noncommutative algebra


math ideal corresponds commutator quotient ring math mathbb c langle x ldotsx n rangle x ix j q ij x jx math math q ij mathbb c math called quantum plane clifford algebra described explicitly using algebra presentation given math mathbb f math vector space math v math dimension quadratic form math q v otimes v mathbb f math associated clifford algebra presentation math mathbb f langle e ldots e n rangle e ie j e je q e ie j math basis math e ldotse n math math v math superalgebras another example noncommutative rings presented math mathbb c x ldotsx n langle theta ldots theta rangle theta theta j theta j theta math


history beginning division rings arising geometry study noncommutative rings grown major area modern algebra theory exposition noncommutative rings expanded refined th th centuries numerous authors incomplete list contributors includes e artin richard brauer p cohn w r hamilton n herstein n jacobson k morita e noether ore others differences commutative noncommutative algebra noncommutative rings much larger class rings commutative rings structure behavior


less well understood great deal work done successfully generalizing results commutative rings noncommutative rings major difference rings commutative necessity separately consider right ideals left ideals common noncommutative ring theorists enforce condition one types ideals requiring hold opposite side commutative rings left right distinction exist important classes division rings division ring also called skew field ring


necessarily commutative ring unity said semisimple completely reducible direct sum simple irreducible submodules ring said left semisimple semisimple left module surprisingly left semisimple ring also right semisimple vice versa left right distinction therefore unnecessary semiprimitive rings semiprimitive ring jacobson semisimple ring j semisimple ring ring whose jacobson radical zero type ring general semisimple ring simple modules still provide enough information ring


rings ring integers semiprimitive artinian semiprimitive ring semisimple ring semiprimitive rings understood subdirect products primitive rings described jacobson density theorem simple rings simple ring non zero ring two sided ideal besides zero ideal simple ring always considered simple algebra rings simple rings modules exist full matrix ring field nontrivial ideals since ideal


''n''''r'' form ''n''''i'' ''i'' ideal ''r'' nontrivial left ideals namely sets matrices fixed zero columns according artin wedderburn theorem every simple ring left right artinian matrix ring division ring particular simple rings finite dimensional vector space real numbers rings matrices either real numbers complex numbers quaternions quotient ring maximal ideal simple ring particular field


simple ring ring ''r'' simple opposite ring ''r'' sup sup simple example simple ring matrix ring division ring weyl algebra important theorems wedderburn 's little theorem wedderburn 's little theorem states every finite domain field words finite rings distinction domains division rings fields artin zorn theorem generalizes theorem alternative rings every finite simple alternative ring field artin wedderburn theorem artin wedderburn theorem classification theorem semisimple rings


semisimple algebras theorem states artinian semisimple ring ''r'' isomorphic product finitely many ''n sub sub '' ''n sub sub '' matrix rings division rings ''d sub sub '' integers ''n sub sub '' uniquely determined permutation index ''i'' particular simple left right artinian ring isomorphic ''n'' ''n'' matrix ring division ring ''d'' ''n'' ''d'' uniquely determined ref name beachy ref direct corollary artin wedderburn theorem implies every simple ring finite dimensional division ring simple algebra


matrix ring joseph wedderburn 's original result emil artin later generalized case artinian rings jacobson density theorem '''jacobson density theorem''' theorem concerning simple modules ring theorem applied show primitive ring viewed dense subring ring linear transformations vector space ref name isaacs isaacs corollary p ref theorem first appeared literature famous paper structure theory simple rings without finiteness assumptions nathan jacobson viewed


kind generalization artin wedderburn theorem 's conclusion structure simple artinian rings formally theorem stated follows '''the jacobson density theorem''' let simple right module end ''u sub r sub '' finite linearly independent set linear transformation exists ''x'' ''r'' nakayama 's lemma let j ''r'' jacobson radical ''r'' ''u'' right module ring ''r'' ''i'' right ideal ''r'' define ''u''''' '''''i''


set finite sums elements form ''u''''' '''''i'' ''' ''' simply action ''r'' ''u'' necessarily ''u''''' '''''i'' submodule ''u'' ''v'' maximal submodule ''u'' ''u'' ''v'' simple ''u''''' '''j ''r'' necessarily subset ''v'' definition j ''r'' fact ''u'' ''v'' simple thus ''u'' contains least one proper maximal submodule ''u''''' '''j ''r'' proper submodule ''u'' however need hold arbitrary modules ''u'' ''r'' ''u'' need contain maximal submodules


naturally ''u'' noetherian module holds ''r'' noetherian ''u'' finitely generated ''u'' noetherian module ''r'' conclusion satisfied somewhat remarkable weaker assumption namely ''u'' finitely generated ''r'' module finiteness assumption ''r'' sufficient guarantee conclusion essentially statement nakayama 's lemma ref name isaacs ref precisely one following '''nakayama 's lemma''' let ''u'' finitely generated right module ring ''r'' ''u'' non zero module ''u''''' '''j ''r'' proper submodule


''u'' ref name isaacs version lemma holds right modules non commutative unitary rings ''r'' resulting theorem sometimes known '''jacobson azumaya theorem''' noncommutative localization localization systematic method adding multiplicative inverses ring usually applied commutative rings given ring ''r'' subset ''s'' one wants construct ring ''r'' ring homomorphism ''r'' ''r'' image ''s'' consists ''units'' invertible elements ''r'' one wants ''r'' 'best possible' 'most general' way


ndash usual fashion expressed universal property localization ''r'' ''s'' usually denoted ''s'' sup nbsp minus sup ''r'' however notations used important special cases ''s'' set non zero elements integral domain localization field fractions thus usually denoted frac ''r'' localizing non commutative rings difficult localization exist every set ''s'' prospective units one condition ensures localization exists ore condition one case non commutative rings localization


two rings ''r'' ''s'' associative said '''morita''' '''equivalent''' equivalence category left modules ''r'' ''r mod'' category left modules ''s'' ''s mod'' shown left module categories ''r mod'' ''s mod'' equivalent right module categories ''mod r'' ''mod s'' equivalent shown functor ''r mod'' ''s mod'' yields equivalence automatically additive brauer group brauer group field ''k'' abelian group whose elements morita


equivalence classes central simple algebras finite rank ''k'' addition induced tensor product algebras arose attempts classify division algebras field named algebraist richard brauer group may also defined terms galois cohomology generally brauer group scheme defined terms azumaya algebras ore conditions ore condition condition introduced ystein ore connection question extending beyond commutative rings construction field fractions


generally localization ring ''right ore condition'' multiplicative subset ''s'' ring ''r'' intersection domain satisfies right ore condition called '''right ore domain''' left case defined similarly goldie 's theorem mathematics '''goldie 's theorem''' basic structural result ring theory proved alfred goldie termed right '''goldie ring''' ring ''r'' finite uniform dimension also called finite rank right module satisfies ascending chain


every commutative integral domain consequence goldie 's theorem due goldie every semiprime principal right ideal ring isomorphic finite direct sum prime principal right ideal rings every prime principal right ideal ring isomorphic matrix ring right ore domain see also derived algebraic geometry noncommutative algebraic geometry noncommutative harmonic analysis representation theory group theory notes references reading ring theory


science policy overlapping field science technology society practitioners study relationship science technology interaction expert lay knowledge public realm scope field started tendency toward navel gazing extremely self conscious genesis applications ref name vulc early concerns scientific discourse practitioners soon started deal relation scientific expertise politics lay people ref name vulc practical examples include bioethics bovine spongiform encephalopathy bse pollution global warming biomedical sciences physical sciences natural hazard predictions alleged impact chernobyl disaster

Social science
Sociology
Science studies


uk generation review science policy risk governance historical geographic contexts ref name vulc staying discipline multiple metanarratives fundamental concern role perceived expert providing governments local authorities information make decisions ref name vulc approach poses various important questions makes expert experts authority distinguished lay population interacts values policy making process liberal democratic societies ref name vulc practitioners examine forces within scientists


investigate specific phenomena technological milieus epistemic instruments cultures laboratory life compare karin knorr cetina bruno latour hans j rg rheinberger science technology eg wiebe bijker trevor pinch thomas p hughes science technology society eg peter weingart ulrike felt helga nowotny reiner grundmann language rhetoric science eg charles bazerman alan g gross greg myers aesthetics science visual culture science ua peter geimer role aesthetic criteria scientific practice compare mathematical beauty relation emotion cognition rationality development science semiotic studies creative processes


discovery conceptualization realization new ideas interaction management different forms knowledge cooperative research large scale research research institutions eg particle colliders sharon traweek research ethics science policy role university history field maria ossowska stanislaw ossowski started introduce concept thomas kuhn 's ''structure scientific revolutions'' led increased interest history science also philosophical underpinnings kuhn 's work established history science less linear succession


discoveries rather concept paradigms philosophy science paradigms broader socio intellectual constructs determine types truth claims permissible science studies try identify crucial dichotomies science technology nature culture theories experiments science fine art leading separation various science fields practices sociology scientific knowledge developed university edinburgh david bloor colleagues developed termed 'strong programme' strong programme proposed 'true' 'false' scientific theories treated way


scrutinized public interaction people things concepts science studies scholars trevor pinch steve woolgar started already involve technology called field science technology society turn technology brought science studies communication academics science technology society programs recently novel approach known mapping controversies gaining momentum among science studies practitioners introduced course students engineering architecture schools harry collins robert evans asked third wave science studies pun


''the third wave'' namely studies ''expertise'' ''experience'' answering recent tendencies dissolve boundary experts public application natural man made hazards sheepfarming chernobyl herdwicks grazing cumbria showcase rather complex problems scientific information interaction lay persons brian wynne 's study sheepfarming cumbria chernobyl disaster ref name vulc ref name mah wynne b sheepfarming chernobyl case study communicating scientific information ''environment'' ref elaborated responses sheep farmers cumbria subjected


administrative restrictions radioactive contamination allegedly caused nuclear accident chernobyl ref name mah sheep farmers suffered economic losses resistance regulation imposed deemed irrational adequate ref name mah turned source radioactivity actually sellafield nuclear reprocessing complex thus experts responsible duration restrictions completely mistaken ref name mah example lead various attempts better involve local knowledge experience lay people assess often highly geographically historically defined background science


studies volcanology aftermath soufri hills eruption montserrat donovan et al used social studies volcanology investigate generation knowledge expert advice various active volcanoes ref name vulc amy donovan clive oppenheimer michael bravo social studies volcanology knowledge generation expert advice active volcanoes bulletin volcanology springer verlag germany pp doi z insu ref contains survey volcanologists carried interviews scientists uk montserrat italy iceland fieldwork seasons donovan et al asked experts


felt purpose volcanology considered important eruptions historical time survey tries identify eruptions influence volcanology science assess role scientists policymaking ref name vulc main focus impact montserrat eruption eruption classical example black swan theory directly killed persons however outbreak major impacts local society destroyed important infrastructure island 's airport people two thirds population left montserrat united


kingdom montserrat case put immense pressure volcanologists expertise suddenly became primary driver various public policy approaches ref name vulc science studies approach provided valuable insights situation ref name vulc various miscommunications among scientists matching scientific uncertainty typical volcanic unrest request single unified voice political advice challenge ref name vulc montserrat volcanologists began use statistical elicitation models estimate probabilities particular events rather subjective method allowing synthesizing consensus experience based expertise step step ref name vulc involved well local knowledge


experience ref name vulc volcanology science currently faces shift epistemological foundations volcanology science started involve research risk assessment risk management requires new integrated methodologies knowledge collection transcend scientific disciplinary boundaries combine qualitative quantitative outcomes structured whole experts democracy science become major force western democratic societies depend innovation technology compare risk society address risks ref name ulrich beck german die risikogesellschaft ref beliefs science different scientists


fuller steve ''the philosophy science technology studies'' new york routledge hess david j ''science studies advanced introduction'' new york nyu press jasanoff sheila ed ''handbook science technology studies'' thousand oaks calif sage publications latour bruno last critique ''harper 's magazine'' april latour bruno ''science action'' cambridge latour bruno believe reality news trenches science wars ''pandora 's hope'' cambridge harvard university press vinck dominique ''the sociology scientific work fundamental relationship science society'' cheltenham edward elgar wyer


mary donna cookmeyer mary barbercheck eds ''women science technology reader feminist science studies'' routledge haraway donna j situated knowledges science question feminism privilege partial perspective ''simians cyborgs women reinvention nature'' new york routledge originally published ''feminist studies'' vol autumn pp nbsp http wwwstaffamuedupl ewa haraway situated knowledgespdf available online foucault michel truth power ''power knowledge'' new york pantheon books porter theodore ''trust numbers pursuit objectivity science public life'' princeton princeton university press restivo sal science society


values toward sociology objectivity lehigh pa lehigh university press medicine biology media culture society technology hancock jeff '' http portalacmorg citationcfmid coll guide dl acm cfid cftoken ret fulltext deception design impact communication technology lying behavior '' lessig lawrence ''free culture'' penguin usa mackenzie donald ''the social shaping technology'' open university press nd ed mitchell william j '' http mitpressmitedu catalog item defaultasptid ttype rethinking media change '' thorburn jennings eds cambridge massachusetts mit press postman neil ''amusing death public discourse age show business'' penguin usa rheingold howard ''smart mobs next social revolution'' cambridge mass perseus


publishing external links https wwwsciencedirectcom topics social sciences science studies '''science studies''' sciencedirect webpage hosting relevant academic articles http wwwcompilerpressca competitiveness anno anno ben david sullivan sociology science ars htm sociology science introductory article joseph ben david teresa sullivan annual review sociology http wwwoikosorg vgknowlhtm incommensurability scientific poetic knowledge http deptswashingtonedu ssnet university washington science studies network historiography science philosophy science pedagogy science technology studies


chemical composition astrophysics broad subject ''astrophysicists'' apply concepts methods many disciplines physics chemistry including classical mechanics electromagnetism statistical mechanics thermodynamics quantum mechanics relativity nuclear particle physics atomic molecular physics practice modern astronomical research often involves substantial amount work realms theoretical observational physics areas study astrophysicists include attempts determine properties dark matter dark energy black holes celestial bodies origin ultimate fate universe ref name nasagov topics also studied theoretical

Natural science
Space science
Astrophysics


astrophysicists include solar system formation evolution stellar dynamics evolution galaxy formation evolution magnetohydrodynamics large scale structure matter universe origin cosmic rays general relativity special relativity quantum physical cosmology including string cosmology astroparticle physics history early comparison elemental solar stellar spectra astronomy ancient science long separated study terrestrial physics aristotelian worldview bodies sky appeared unchanging spheres whose motion uniform motion circle earthly world realm underwent growth decay


natural motion straight line ended moving object reached goal consequently held celestial region made fundamentally different kind matter found terrestrial sphere either fire maintained plato aether maintained aristotle th century natural philosophers galileo descartes newton began maintain celestial terrestrial regions made similar kinds material subject natural laws ref name burtt challenge tools


yet invented prove assertions much nineteenth century astronomical research focused routine work measuring positions computing motions astronomical objects new astronomy soon called astrophysics began emerge william hyde wollaston joseph von fraunhofer independently discovered decomposing light sun multitude dark lines regions less light observed spectrum physicist gustav kirchhoff chemist robert bunsen demonstrated dark


types following pickering 's vision cannon expanded catalog nine volumes quarter million stars developing harvard classification scheme accepted worldwide use george ellery hale james e keeler along group ten associate editors europe united states ref name hale ref established ''the astrophysical journal international review spectroscopy astronomical physics'' intended journal would fill gap journals astronomy physics providing venue publication articles astronomical applications


spectroscope laboratory research closely allied astronomical physics including wavelength determinations metallic gaseous spectra experiments radiation absorption theories sun moon planets comets meteors nebulae instrumentation telescopes laboratories ref name hale around following discovery hertzsprung russell diagram still used basis classifying stars evolution arthur eddington anticipated discovery mechanism nuclear fusion processes stars paper ''the internal constitution stars'' ref name eddington ref ref name eddington ref time source stellar energy


complete mystery eddington correctly speculated source fusion hydrogen helium liberating enormous energy according einstein 's equation ''e mc sup sup '' particularly remarkable development since time fusion thermonuclear energy even stars largely composed hydrogen see metallicity yet discovered cecilia helena payne later cecilia payne gaposchkin wrote influential doctoral dissertation radcliffe college applied ionization theory stellar atmospheres relate spectral classes temperature stars significantly discovered hydrogen helium


principal components stars despite eddington 's suggestion discovery unexpected dissertation readers convinced modify conclusion publication however later research confirmed discovery end th century studies astronomical spectra expanded cover wavelengths extending radio waves optical x ray gamma wavelengths st century expanded include observations based gravitational waves observational astrophysics supernova remnant lmc n imaged x ray blue optical green radio red wavelengths x ray glow material heated ten million degrees


celsius shock wave generated supernova explosion observational astronomy division astronomical science concerned recording interpreting data contrast theoretical astrophysics mainly concerned finding measurable implications physical models practice observing celestial objects using telescopes astronomical apparatus majority astrophysical observations made using electromagnetic spectrum radio astronomy studies radiation wavelength greater millimeters example areas study radio waves usually emitted cold objects interstellar gas


dust clouds cosmic microwave background radiation redshifted light big bang pulsars first detected microwave frequencies study waves requires large radio telescopes infrared astronomy studies radiation wavelength long visible naked eye shorter radio waves infrared observations usually made telescopes similar familiar optical telescopes objects colder stars planets normally studied infrared frequencies optical astronomy earliest kind astronomy telescopes paired charge coupled device


spectroscopes common instruments used earth 's atmosphere interferes somewhat optical observations adaptive optics space telescopes used obtain highest possible image quality wavelength range stars highly visible many chemical spectra observed study chemical composition stars galaxies nebulae ultraviolet x ray gamma ray astronomy study energetic processes binary pulsars black holes magnetars many others kinds radiation penetrate earth 's atmosphere well two methods use observe part electromagnetic spectrum space based


also vary time scale optical observations take minutes hours phenomena change faster cannot readily observed however historical data objects available spanning centuries millennia hand radio observations may look events millisecond timescale millisecond pulsars combine years data pulsar deceleration studies information obtained different timescales different study sun special place observational astrophysics due tremendous distance stars sun observed


kind detail unparalleled star understanding sun serves guide understanding stars topic stars change stellar evolution often modeled placing varieties star types respective positions hertzsprung russell diagram viewed representing state stellar object birth destruction theoretical astrophysics theoretical astrophysicists use wide variety tools include analytical models example polytropes approximate behaviors star computational numerical simulations advantages


analytical models process generally better giving insight heart going numerical models reveal existence phenomena effects would otherwise seen theorists astrophysics endeavor create theoretical models figure observational consequences models helps allow observers look data refute model help choosing several alternate conflicting models theorists also try generate modify models take account new data case inconsistency general tendency


try make minimal modifications model fit data cases large amount inconsistent data time may lead total abandonment model topics studied theoretical astrophysicists include stellar dynamics evolution galaxy formation evolution magnetohydrodynamics large scale structure matter universe origin cosmic rays general relativity physical cosmology including string cosmology astroparticle physics astrophysical relativity serves tool gauge properties large scale structures gravitation plays significant role physical phenomena investigated basis black hole ''astro'' physics


study gravitational waves widely accepted studied theories models astrophysics included lambda cdm model big bang cosmic inflation dark matter dark energy fundamental theories physics popularization roots astrophysics found seventeenth century emergence unified physics laws applied celestial terrestrial realms ref name burtt ref scientists qualified physics astronomy laid firm foundation current science astrophysics modern times students continue


galaxies large scale structure timeline white dwarfs neutron stars supernovae references reading http wwwscholarpediaorg article encyclopedia astrophysics astrophysics scholarpedia expert articles external links http wwwworldscinetcom ijmpd ijmpdshtml ''international journal modern physics d'' world scientific http wwwaiporg history cosmology indexhtm cosmic journey history scientific cosmology american institute physics http wwwvegaorguk video subseries prof sir harry kroto nl astrophysical chemistry lecture series freeview lectures provided vega science trust https webarchiveorg web http homeslacstanfordedu ppaphtml stanford linear accelerator center stanford california http wwwiasfboinafit institute space astrophysics cosmic physics http iopscienceioporg x ''astrophysical journal'' http wwwaandaorg ''astronomy astrophysics'' european journal http wwwscienceresourceworldcom publications journals astronomy journalshtml list directory peer reviewed astronomy


photochemical immersion well reactor ml mercury vapor lamp '''photochemistry''' branch chemistry concerned chemical effects light generally term used describe chemical reaction caused absorption ultraviolet wavelength nbsp nm visible light nbsp nm infrared radiation nbsp nm nature photochemistry immense importance basis photosynthesis vision formation vitamin sunlight photochemical reactions proceed differently temperature driven reactions photochemical paths access high energy intermediates cannot generated thermally thereby overcoming large activation barriers

Natural science
Chemistry
Photochemistry


short period time allowing reactions otherwise inaccessible thermal processes photochemistry also destructive illustrated photodegradation plastics concept grotthuss draper law stark einstein law photoexcitation first step photochemical process reactant elevated state higher energy excited state first law photochemistry known grotthuss draper law chemists theodor grotthuss john w draper states light must absorbed chemical substance order photochemical reaction take place according second law photochemistry known


stark einstein law physicists johannes stark albert einstein photon light absorbed chemical system one molecule activated photochemical reaction defined quantum yield fluorescence phosphorescence molecule atom ground state sub sub absorbs light one electron excited higher orbital level electron maintains spin according spin selection rule transitions would violate law conservation angular momentum excitation higher singlet state homo lumo higher orbital


singlet excitation states sub sub sub sub sub sub different energies possible kasha 's rule stipulates higher singlet states would quickly relax radiationless decay internal conversion ic sub sub thus sub sub usually always relevant singlet excited state excited state sub sub relax sub sub ic also allowed radiative transition sub sub sub sub emits photon process called fluorescence jablonski diagram radiative paths represented straight arrows non radiative paths curly lines alternatively possible excited state sub sub


undergo spin inversion generate triplet excited state sub sub two unpaired electrons spin violation spin selection rule possible intersystem crossing isc vibrational electronic levels sub sub sub sub according hund 's rule maximum multiplicity sub sub state would somewhat stable sub sub triplet state relax ground state sub sub radiationless ic radiation pathway called phosphorescence process implies change electronic spin forbidden spin selection rules making phosphorescence sub sub


sub sub much slower fluorescence sub sub sub sub thus triplet states generally longer lifetimes singlet states transitions usually summarized state energy diagram jablonski diagram paradigm molecular photochemistry excited species either sub sub sub sub half empty low energy orbital consequently oxidizing ground state time electron high energy orbital thus reducing general excited species prone participate electron transfer processes experimental set photochemical immersion well reactor ml


beams schlenk tube containing slurry orange crystals fe sub sub co sub sub acetic acid photochemical synthesis fe co sub sub mercury lamp connected white power cords seen left set inside water jacketed quartz tube emitted light must course reach targeted functional group without blocked reactor medium functional groups present many applications quartz used reactors well contain lamp pyrex absorbs wavelengths shorter nbsp nm solvent important experimental parameter solvents potential reactants reason


chlorinated solvents avoided c cl bond lead chlorination substrate strongly absorbing solvents prevent photons reaching substrate hydrocarbon solvents absorb short wavelengths thus preferred photochemical experiments requiring high energy photons solvents containing unsaturation absorb longer wavelengths usefully filter short wavelengths example cyclohexane acetone cut absorb strongly wavelengths shorter nbsp nm respectively photochemistry combination flow chemistry continuous flow photochemistry offers multiple advantages batch photochemistry photochemical reactions driven number photons able


activate molecules causing desired reaction large surface area volume ratio microreactor maximizes illumination time allows efficient cooling decreases thermal side products principles case photochemical reactions light provides activation energy simplistically light one mechanism providing activation energy required many reactions laser light employed possible selectively excite molecule produce desired electronic vibrational state ref name wavelength dependence ref equally emission particular state may selectively monitored providing measure


population state chemical system low pressure enables scientists observe energy distribution products chemical reaction differences energy smeared averaged repeated collisions absorption photon light reactant molecule may also permit reaction occur bringing molecule necessary activation energy also changing symmetry molecule 's electronic configuration enabling otherwise inaccessible reaction path described woodward hoffmann selection rules cycloaddition reaction


photodegradation '''photodynamic therapy''' light used destroy tumors action singlet oxygen generated photosensitized reactions triplet oxygen typical photosensitizers include tetraphenylporphyrin methylene blue resulting singlet oxygen aggressive oxidant capable converting c h bonds c oh groups diazo printing process photoresist technology used production microelectronic components vision initiated photochemical reaction rhodopsin ref name rh ref toray photochemical production caprolactame photochemical production artemisinin anti malaria drug photoalkylation used light induced addition alkyl groups molecules organic photochemistry examples photochemical organic reactions electrocyclic reactions


radical reactions photoisomerization norrish reactions norrish type ii reaction alkenes undergo many important reactions proceed via photon induced transition first electronic excited state alkene lack bond rotation c c bond rapid molecule engages reactions observed thermally reactions include cis trans isomerization cycloaddition ground state alkene give cyclobutane derivatives cis trans isomerization poly alkene involved retinal component machinery vision dimerization alkenes relevant photodamage dna thymine dimers


observed upon illuminating dna uv radiation dimers interfere transcription beneficial effects sunlight associated photochemically induced retro cyclization decyclization reaction ergosterol give vitamin demayo reaction alkene reacts diketone reacts via enol yield diketone still another common photochemical reaction zimmerman 's di pi methane rearrangement industrial application tonnes benzyl chloride prepared annually gas phase photochemical reaction toluene chlorine ref name ullmann ref light absorbed chlorine molecule low energy transition indicated yellowish


color gas photon induces homolysis cl cl bond resulting chlorine radical converts toluene benzyl radical cl sub sub h cl c sub sub h sub sub ch sub sub cl c sub sub h sub sub ch sub sub hcl c sub sub h sub sub ch sub sub cl c sub sub h sub sub ch sub sub cl mercaptans produced photochemical addition hydrogen sulfide h sub sub alpha olefins inorganic organometallic photochemistry coordination complexes organometallic compounds also photoreactive reactions entail cis trans isomerization commonly photoreactions result dissociation ligands since photon excites electron metal orbital antibonding respect


ligands thus metal carbonyls resist thermal substitution undergo decarbonylation upon irradiation uv light uv irradiation thf solution molybdenum hexacarbonyl gives thf complex synthetically useful mo co sub sub thf mo co sub sub thf co related reaction photolysis iron pentacarbonyl affords diiron nonacarbonyl see figure fe co sub sub fe sub sub co sub sub co select photoreactive coordination complexes undergo oxidation reduction processes via single electron transfer electron transfer occur within inner outer coordination sphere metal historical although bleaching long practiced first photochemical reaction described trommsdorff


observed crystals compound santonin exposed sunlight turned yellow burst study reaction described succession three steps taking place within single crystal santonin photochemical reaction first step rearrangement reaction cyclopentadienone intermediate ''' ''' second one dimerization diels alder reaction ''' ''' third one intramolecular cycloaddition ''' ''' bursting effect attributed large change crystal volume dimerization see also photonic molecule photoelectrochemical cell photochemical logic gate photosynthesis light dependent reactions list photochemists single


photon sources photogeochemistry photoelectric effect photolysis references reading bowen e j '' https archiveorg details chemicalaspectso mbpthe chemical aspects light '' oxford clarendon press https openlibraryorg books ol chemical aspects light nd edition https www chemistrymsuedu faculty reusch virttxtjml photchemhtm photochemistry chemistry


founded first psychology laboratory leipzig germany ref name khaleefa ref experimental psychologists including hermann ebbinghaus edward titchener included introspection among experimental methods charles bell charles bell british physiologist whose main contribution research involving nervous system wrote pamphlet summarizing research rabbits research concluded sensory nerves enter posterior dorsal roots spinal cord motor nerves emerge anterior ventral roots spinal cord eleven years later french physiologist francois magendie published findings without aware bell 's research due

Social science
Psychology
Experimental psychology


bell publishing research discovery called bell magendie law bell 's discovery disproved belief nerves transmitted either vibrations spirits ernst heinrich weber weber german physician credited one founders experimental psychology weber 's main interests sense touch kinesthesis memorable contribution field experimental psychology suggestion judgments sensory differences relative absolute relativity expressed weber 's law suggests noticeable difference '''jnd''' constant proportion


ongoing stimulus level weber 's law stated equation math frac delta k math math math original intensity stimulation math delta math addition required difference perceived '''jnd''' ''k'' constant thus k remain constant math delta math must rise '''i''' increases weber 's law considered first quantitative law history psychology gustav fechner fechner published considered first work experimental psychology elemente der psychophysik ref name fraisse fraisse


p piaget j reuchlin experimental psychology scope method history method new york basic books ref historians date beginning experimental psychology publication elemente weber psychologist fechner realized importance weber 's research psychology fechner profoundly interested establishing scientific study mind body relationship became known psychophysics much fechner 's research focused measurement psychophysical thresholds noticeable differences invented psychophysical method limits method


constant stimuli method adjustment still use oswald k lpe oswald k lpe main founder w rzburg school germany pupil wilhelm wundt twelve years unlike wundt k lpe believed experiments possible test higher mental processes wrote grundriss der psychologie strictly scientific facts mention thought ref name fraisse lack thought book odd w rzburg school put lot emphasis mental set imageless thought w rzburg


school work w rzburg school milestone development experimental psychology school founded group psychologists led oswald k lpe provided alternative structuralism edward titchener wilhelm wundt school focused mainly mental operations mental set ''einstellung'' imageless thought mental set affects perception problem solving without awareness individual triggered instructions experience similarly according k lpe imageless thought consists pure mental acts


involve mental images example mental set provided william bryan american student working k lpe 's laboratory bryan presented subjects cards nonsense syllables written various colors subjects told attend syllables consequence remember colors nonsense syllables results made people question validity introspection research tool led decline voluntarism structuralism work w rzburg school later influenced many gestalt psychologists including max wertheimer george


trumbull ladd experimental psychology introduced united states george trumbull ladd founded yale university 's psychological laboratory ladd published ''elements physiological psychology'' first american textbook extensively discussed experimental psychology ladd 's founding yale laboratory textbook center experimental psychology us shifted johns hopkins university george hall charles sanders peirce extending qualifying wundt 's work charles sanders peirce charles sanders peirce joseph jastrow student joseph jastrow charles peirce randomly assigned volunteers blinded


repeated measures design evaluate ability discriminate weights ref name smalldiff ref ref name telepathy ref ref name stigler ref ref name dehue ref peirce 's experiment inspired researchers psychology education developed research tradition randomized experiments laboratories specialized textbooks ref name smalldiff ref name telepathy ref name stigler ref name dehue peirce jastrow experiments conducted part peirce 's pragmatic program understand human perception studies considered perception light etc peirce making advances experimental psychology psychophysics also developing theory statistical inference published illustrations logic science theory probable inference


publications emphasized importance randomization based inference statistics peirce experimental psychology belongs honor invented randomized experiments decades innovations jerzy neyman ronald fisher agriculture ref name smalldiff ref name telepathy ref name stigler ref name dehue peirce 's pragmaticist philosophy also included extensive theory mental representations cognition studied name semiotics peirce 's student joseph jastrow continued conduct randomized experiments throughout distinguished career experimental psychology much would later recognized cognitive psychology resurgence interest peirce 's work


cognitive psychology another student peirce john dewey conducted experiments human cognition particularly schools part experimental logic public philosophy th century middle th century behaviorism became dominant paradigm within psychology especially united states led neglect mental phenomena within experimental psychology europe less case european psychology influenced psychologists sir frederic bartlett kenneth craik hick donald broadbent focused topics thinking memory attention laid foundations


subsequent development cognitive psychology latter half th century phrase experimental psychology shifted meaning due expansion psychology discipline growth size number sub disciplines experimental psychologists use range methods confine strictly experimental approach partly developments philosophy science affected exclusive prestige experimentation contrast experimental method widely used fields developmental social psychology previously part experimental psychology


phrase continues use however titles number well established high prestige learned societies scientific journals well university courses study psychology methodology sound methodology essential study complex behavioral mental processes implies especially careful definition control experimental variables assumptions empiricism perhaps basic assumption science factual statements world must ultimately based observations world notion empiricism requires hypotheses theories tested


observations natural world rather priori reasoning intuition revelation testability closely related empiricism idea useful scientific law theory must testable available research methods theory cannot tested conceivable way many scientists consider theory meaningless testability implies falsifiability idea set observations could prove theory incorrect testability emphasized psychology influential well known theories like freud difficult test


determinism experimental psychologists like scientists accept notion determinism assumption state object event determined prior states words behavioral mental phenomena typically stated terms cause effect phenomenon sufficiently general widely confirmed may called law psychological theories serve organize integrate laws parsimony another guiding idea science parsimony search simplicity example scientists agree two theories handle set empirical observations equally


well prefer simpler parsimonious two notable early argument parsimony stated medieval english philosopher william occam reason principle parsimony often referred occam 's razor operational definition well known behaviorists edward c tolman clark hull popularized idea operationism operational definition operational definition implies concept defined terms concrete observable procedures experimental psychologists attempt define currently unobservable phenomena mental events connecting observations chains


reasoning experiments experiments human participants often respond visual auditory stimuli following instructions given experimenter animals may similarly instructed rewarding appropriate responses since computers commonly used automate stimulus presentation behavioral measurement laboratory behavioral experiments humans animals typically measure reaction time choices among two alternatives response rate strength may also record movements facial expressions behaviors experiments humans may also obtain written responses experimental procedures psychophysiological experiments


hand measure brain mostly animals single cell activation presentation stimulus using methods fmri eeg pet similar control extraneous variables minimizing potential experimenter bias counterbalancing order experimental tasks adequate sample size use operational definitions emphasis reliability validity results proper statistical analysis central experimental methods psychology understanding matters important interpretation data almost fields psychology undergraduate programs psychology usually include mandatory courses research methods


self reports '''field experiment''' participants observed naturalistic setting outside laboratory field experiments differ field ' 'studies'' part environment ''field'' manipulated controlled way example researchers give different kinds toys two different groups children nursery school control typically lax would laboratory setting methods research case study interview opinion polls naturalistic observation often used psychologists experimental methods lack aspects well defined controlled variables


measured comparing test results groups important note reliable measure need yield valid conclusion validity validity measures relative accuracy correctness conclusions drawn study determine validity measurement quantitatively must compared criterion example determine validity test academic ability test might given group students results correlated grade point averages individuals group example suggests often


external validity refers extent outcome experiment generalized apply situations experiment example people physical social environments even cultures construct validity construct validity refers extent independent dependent variables study represent abstract hypothetical variables interest words whether manipulated measured variables study accurately reflect variables researcher hoped manipulate construct validity also reflects


quality one 's operational definitions researcher done good job converting abstract observable construct validity high conceptual validity conceptual validity refers well specific research maps onto broader theory designed test conceptual construct validity lot common conceptual validity relates study broad theoretical issues whereas construct validity specific manipulations measures scales measurement measurement defined assignment numerals objects events according rules ref name


measurement nominal scale numbers used simply labels letter name would well examples numbers shirts football baseball players labels useful label given one thing meaning things equal way classified together ordinal measurement ordinal scale arises ordering ranking objects greater b b greater c many psychological experiments yield numbers


sort example participant might able rank odors pleasant b b pleasant c rankings would tell much odor differed another statistics computed ordinal measures example median percentile order correlation others standard deviation cannot properly used interval measurement interval scale constructed determining equality differences things measured numbers form interval scale


differences numbers correspond differences properties measured instance one say difference degrees fahrenheit thermometer equals difference meaningless say something temperature degrees fahrenheit twice hot something temperature degrees ratios meaningful absolute temperature scale kelvin scale see next section standard scores achievement test said measurements interval scale difficult


prove ref name stevens ratio measurement ratio scale constructed determining equality ratios example balance instrument object balances two identical objects b one say twice heavy b give appropriate numbers example weighs grams b weighs gram key idea ratios remain regardless scale units used example ratio b remains whether grams ounces used length resistance kelvin


temperature things measured ratio scales psychological properties loudness sound measured ratio scale ref name stevens research design one way designs simplest experimental design one way design one independent variable simplest kind one way design involves two groups receives one value independent variable two group design typically consists experimental group group receives treatment control group group receive


treatment one way design may expanded one way multiple groups design single independent variable takes three levels type design particularly useful help outline functional relationship independent dependent variables factorial designs one way designs limited allow researchers look one independent variable time whereas many phenomena interest dependent multiple variables ra fisher popularized use factorial designs factorial designs contain two independent variables


completely crossed means every level independent variable appears combination every level independent variables factorial designs carry labels specify number independent variables number levels independent variable design example x factorial design two independent variables two numbers description first variable two levels second three main effects interactions effects independent variables factorial studies taken singly referred main effects refers


overall effect independent variable averaging across levels independent variables main effect effect detectable one way design often important main effects interactions occur effect one independent variable dependent variable depends level second independent variable example ability catch ball dependent variable might depend interaction visual acuity independent variable size ball caught independent variable person good eyesight might catch


small ball easily person poor eyesight might better large ball two variables said interact within subjects designs two basic approaches research design within subjects design subjects design within subjects repeated measures designs participant serves one perhaps conditions study subjects designs participant serves one condition experiment within subjects designs significant advantages subjects designs especially comes complex factorial designs many conditions


particular within subjects designs eliminate person confounds get rid effects caused differences among subjects irrelevant phenomenon study however within subject design serious disadvantage possible sequence effects participant serves one condition passage time performance earlier task may affect performance later task example participant might learn something first task affects second experimental instruments instruments used experimental psychology evolved along technical advances shifting


demands experiments earliest instruments hipp chronoscope kymograph originally used purposes list exemplifies different instruments used years hipp chronoscope chronograph instrument invented matth us hipp around uses vibrating reed tick time ths second originally designed experiments physics later adapted study speed bullets introduced physiology finally used psychology measure reaction time duration mental processes


measurement function time kymograph similar polygraph strip paper moving one pens kymograph originally used measure blood pressure later used measure muscle contractions speech sounds psychology often used record response times photokymographs device photographic recorder used mirrors light record photos inside small box slit light two drive rollers film connecting two


light enters slit record film photokymographs lens appropriate speed film reached galvanometer galvanometer early instrument used measure strength electric current hermann von helmholtz used detect electrical signals generated nerve impulses thus measure time taken impulses travel two points nerve audiometer apparatus designed produce several fixed frequencies different levels intensity could either deliver


tone subject 's ear transmit sound oscillations skull experimenter would generally use audiometer find auditory threshold subject data received audiometer called audiogram colorimeters determine color composition measuring tricolor characteristics matching color sample type device would used visual experiments ref name stevens algesiometers algometers mechanical stimulations pain sharp needle like stimulus point give sensation pressure


experimenters use experiment analgesia olfactometer olfactometer device used measure sense smell basic type early studies placing subject room containing specific measured amount odorous substance intricate devices involve form sniffing device neck bottle common olfactometer found psychology laboratories one point zwaardemker olfactometer two glass nasal tubes projecting screen one end would inserted


maze meant test spatial learning uses large round pool water made opaque rat must swim around finds escape platform hidden view surface water electroencephalograph eeg eeg instrument reflect summed electrical activity neural cell assemblies brain originally used attempt improve medical diagnoses later became key instrument psychologists examining brain activity remains key instrument used


field today functional magnetic resonance imaging fmri fmri instrument detect changes blood oxygen levels time increase blood oxygen levels shows brain activity occurs rather bulky expensive instruments generally found hospitals commonly used cognitive experiments positron emission tomography pet pet also used look brain activity detect drugs binding neurotransmitter receptors brain side pet requires radioisotopes injected


body brain activity mapped radioisotopes decay quickly accumulate body research areas employ experimental methods use experimental methods perhaps main characteristic psychology became distinguishable philosophy late th century ever since experiments integral part psychological research following sample major areas use experimental methods cognitive psychology major topics studied cognitive psychologists memory learning problem solving


research field often focuses matters similar interest cognitive psychologists using human participants cognitive studies using animals often control conditions closely use methods open research humans addition processes conditioning appear simpler form animals certain animals display unique capacities echo location bats clarify important cognitive functions animal studies often important implications survival evolution species sensation perception experiments sensation perception long history experimental


psychology see history experimenters typically manipulate stimuli affecting vision hearing touch smell taste proprioception sensory measurement plays large role field covering many aspects sensory performance example minimum discriminable differences brightness detection odors measurement involves use instruments oscillator attenuator stroboscope many others listed earlier article experiments also probe subtle phenomena visual illusions emotions aroused stimuli different sorts behavioral psychology behavioristic approach psychology reached peak popularity


mid twentieth century still underlies much experimental research clinical application founders include figures ivan pavlov john b watson bf skinner pavlov 's experimental study digestive system dogs led extensive experiments established basic principles classical conditioning watson popularized behaviorist approach human behavior experiments little albert particularly well known skinner distinguished operant conditioning classical conditioning established experimental analysis behavior major component subsequent development experimental psychology social psychology social


psychologists use experimental methods within outside laboratory attempt understand human social interaction two widely cited experiments social psychology experiment stanford prison experiment conducted philip zimbardo milgram obedience experiment stanley milgram experiments ordinary individuals induced engage remarkably cruel behavior suggesting behavior strongly influenced social pressure possible negative effects participants neither experiments could legally performed united states today institutional review board irb


united states institutional review boards irbs play important role monitoring conduct psychological experiments presence required law institutions universities psychological research occurs purpose make sure experiments violate ethical codes legal requirements thus protect human subjects physical psychological harm assure humane treatment animal subjects irb must review procedure used experiment experiment may begin irb also assures human participants give informed consent advance


participants told general nature experiment required three types review may undertaken irb exempt expedited full review information available main irb page criticism frankfurt school one school opposed experimental psychology associated frankfurt school calls ideas critical theory critical psychologists claim experimental psychology approaches humans entities independent cultural economic historical context exist contexts human mental processes behavior


neglected according critical psychologists like herbert marcuse experimental psychologists paint inaccurate portrait human nature lending tacit support prevailing social order according critical theorists like theodor adorno j rgen habermas essays ''the positivist debate german sociology'' see also empirical psychology outline psychology psychonomic society sackett self selection circus society experimental psychologists notes references mathematical quantitative methods economics


sweeny english language introduced ireland thirteenth century following norman invasion ireland irish language however remained dominant language irish literature nineteenth century despite slow decline began seventeenth century expansion english power latter part nineteenth century saw rapid replacement irish english greater part country largely due great famine subsequent decimation irish population starvation emigration end century however cultural nationalism displayed

Humanities
Languages and literature
Irish Literature


th century irish literature saw unprecedented sequence globally successful works especially oscar wilde bram stoker james joyce w b yeats samuel beckett elizabeth bowen c lewis kate o'brien george bernard shaw left ireland make life european countries england spain france switzerland meantime descendants scottish settlers ulster formed ulster scots writing tradition especially strong tradition rhyming poetry though english dominant irish literary language twentieth century much work high quality appeared irish


pioneering modernist writer irish p draic conaire traditional life given vigorous expression series autobiographies native irish speakers west coast exemplified work tom criomhthain peig sayers ir ad n ghr da wrote numerous successful plays often influenced bertolt brecht well first translation peter pan ''t r na deo'' ''manann n'' first irish language science fiction book outstanding modernist prose writer irish irt n cadhain prominent poets included caitl n maude irt n dire se n r ord ire mhac


tsaoi prominent bilingual writers included brendan behan wrote poetry play irish flann o'brien two novels o'brien ''at swim two birds'' ''the third policeman'' considered early examples postmodern fiction also wrote satirical novel irish called ''an b al bocht'' translated ''the poor mouth'' liam o'flaherty gained fame writer english also published book short stories irish ''d il'' irish language literature continues flourish modern day il n dhuibhne nuala n dhomhnaill prolific poetry prose attention


friel novelists edna o'brien john mcgahern late twentieth century irish poets especially northern ireland came prominence including derek mahon medbh mcguckian john montague seamus heaney paul muldoon influential works writing continue emerge northern ireland huge success anna burns sin ad morrissey lisa mcgee well known irish writers english twenty first century include edna o'brien colum mccann anne enright roddy doyle moya cannon john boyne sebastian barry colm toib n john banville major awards younger writers include sin ad gleeson paul


murray anna burns billy o'callaghan kevin barry emma donoghue donal ryan sally rooney dramatists marina carr martin mcdonagh writing irish also continued flourish middle ages irish writing th century irish one oldest vernacular literatures western europe greek latin irish became fully literate arrival christianity fifth century time simple writing system known ogham used inscriptions inscriptions mostly simple x son statements introduction latin led adaptation


latin alphabet irish language rise small literate class clerical lay earliest works literature produced ireland saint patrick ''confessio'' ''epistola'' latin earliest literature irish consisted original lyric poetry prose sagas set distant past earliest poetry composed th century illustrates vivid religious faith describes world nature sometimes written margins illuminated manuscripts blackbird belfast lough fragment syllabic verse probably dating th


century inspired reinterpretations translations modern times john montague john hewitt seamus heaney ciaran carson thomas kinsella well version modern irish tom floinn ''book armagh'' th century illuminated manuscript written mainly latin containing early texts relating st patrick oldest surviving specimens old irish one earliest manuscripts produced insular church contain near complete copy new testament manuscript work scribe named ferdomnach armagh died


ferdomnach wrote first part book patrick 's heir ''comarba'' torbach one symbols office archbishop armagh annals ulster cover years ad ad compiled territory northern ireland entries ad compiled late th century scribe ruaidhr luin n patron cathal g mac maghnusa island belle isle lough erne ulster cycle written th century


body medieval irish heroic legends sagas traditional heroes ulaid eastern ulster northern leinster particularly counties armagh louth stories written old middle irish mostly prose interspersed occasional verse passages language earliest stories dateable th century events characters referred poems dating th old irish period vast range poetry mediaeval renaissance times degrees irish created classical tradition


language verse remained main vehicle literary expression th century questions form style essentially settled little change th century medieval irish writers also created extensive literature latin hiberno latin literature notable learned vocabulary including greater use loanwords greek hebrew common medieval latin elsewhere europe literary irish language known english classical irish sophisticated medium elaborate verse forms taught bardic schools ie academies higher learning


ireland scotland produced historians lawyers professional literary class depended aristocracy patronage much writing produced period conventional character praise patrons families best exceptionally high quality included poetry personal nature gofraidh fionn laigh th century tadhg g huiginn th century eochaidh heoghusa th century among distinguished poets every noble family possessed body manuscripts containing genealogical material work best


poets used teaching purposes bardic schools hierarchical society fully trained poets belonged highest stratum court officials thought still possess ancient magical powers women largely excluded official literature though female aristocrats could patrons right example th century noblewoman mairgr ag n cearbhaill praised learned hospitality level certain number women literate contributors unofficial corpus courtly love poetry known ' 'd nta gr dha'' prose continued


cultivated medieval period form tales norman invasion th century introduced new body stories influenced irish tradition time translations made english irish poets also composed ''dindsenchas'' lore places class onomastic texts recounting origins place names traditions concerning events characters associated places question since many legends related concern acts mythic legendary figures ' 'dindsenchas'' important source study irish mythology irish mythological legendary saga cycles navan


fort identified ancient emain macha setting many tales ulster cycle early irish literature usually arranged four epic cycles cycles considered contain series recurring characters locations first mythological cycle concerns irish pagan pantheon tuatha danann recurring characters stories lug dagda engus many tales set around br na b inne principle tale mythological cycle ''cath maige tuired'' ''the battle moytura'' shows tuatha


danann defeated fomorians later synthetic histories ireland placed battle occurring time trojan war second ulster cycle mentioned also known red branch cycle heroic cycle cycle contains tales conflicts ulster connacht legendary reigns king conchobar mac nessa ulster medb ailill connacht chief saga ulster cycle ''t b c ailnge'' called iliad gael recurring characters include c chulainn figure comparable greek hero achilles known


terrifying battle frenzy ''r astrad'' fergus conall cernach emain macha cruachan chief locations cycle set around end st century bc beginning st century ad death conchobar set day crucifixion third body romance woven round fionn mac cumhaill son oisin grandson oscar reigns high king ireland cormac mac airt second third centuries ad cycle romance usually called fenian cycle


span thousand years though many stories feature conn c tchathach niall g allach hill tara common location unusually among european epic cycles irish sagas written prosimetrum ie prose verse interpolations expressing heightened emotion although usually found manuscripts later periods many works feature language older time manuscripts contained poetry embedded tales often significantly older tale contained unusual see poetry old


irish period tale written principally middle irish four cycles common readers today invention modern scholars several tales fit neatly one category category early irish writers though tales terms genre 's ''aided'' death tales ''aislinge'' visions ''cath'' battle tales ''echtra'' adventures ''immram'' voyages ''t b '' cattle raids ''tochmarc'' wooings ''togail'' destructions well irish mythology also adaptations middle irish classical mythological tales ''togail tro '' destruction


troy adapted ''daretis phrygii de excidio trojae historia'' purportedly dares phrygius ''togail na tebe'' destruction thebes statius' ''thebaid '' ''imtheachta niasa'' virgil 's ''aeneid'' early modern period th century saw tightening english control ireland suppression traditional aristocracy meant literary class lost patrons since new nobility english speakers little sympathy older culture elaborate classical metres lost dominance largely replaced popular forms age social political tension


expressed poet ibh bruadair anonymous authors ''pairliment chloinne tom is'' prose satire aspirations lower classes prose another sort represented historical works geoffrey keating seathr n c itinn compilation known ''annals four masters'' consequences changes seen th century poetry still dominant literary medium practitioners often poor scholars educated classics local schools schoolmasters trade writers produced polished work popular metres local audience


copied recopied might include material several centuries old access confined literate since contents read aloud local gatherings still case late th century irish speaking districts manuscripts often taken abroad particularly america th century many collected individuals cultural institutions anglo irish tradition th century jonathan swift powerful versatile satirist ireland 's first earliest notable writer english swift held positions authority england ireland different times


performed edmund burke born dublin came serve house commons great britain behalf whig party establish reputation oratory published works great philosophical clarity well lucid literary style literature ulster scots th century scots mainly gaelic speaking settling ulster since th century large numbers scots speaking lowlanders arrived th century following plantation peak reached ref name montgomery gregg montgomery


gregg ref core areas scots settlement scots outnumbered english settlers five six one ulster scots speaking areas work scottish poets allan ramsay robert burns popular often locally printed editions complemented poetry revival nascent prose genre ulster started around ref name robinson ''the historical presence ulster scots ireland'' robinson ''the languages ireland'' ed cronin cuillean dublin ref tradition poetry prose ulster scots began around ref name robinson


prominent ''''rhyming weaver'''' poetry publication began though broadsheet published strabane ref name rhyming weavers hewitt ''rhyming weavers'' hewitt ref weaver poets looked scotland cultural literary models simple imitators inheritors literary tradition followed poetic orthographic practices always immediately possible distinguish traditional scots writing scotland ulster among ''rhyming weavers'' james campbell james orr thomas beggs modern period


th century english well way becoming dominant vernacular great famine however even later irish still used large areas south west west north west famous long poem beginning century ''c irt mhe n che'' midnight court vigorous inventive satire brian merriman county clare copying manuscripts continued unabated one collection possession amhlaoibh illeabh teacher linen draper county kilkenny kept unique diary


vernacular irish covering local international events wealth information daily life great famine hastened retreat irish language many speakers died hunger fever many emigrated hedge schools earlier decades helped maintain native culture supplanted system national schools english given primacy literacy irish restricted vigorous english speaking middle class dominant cultural force number members influenced


live young closely identified ireland pioneer realist novel irish novelists emerge th century include john banim gerald griffin charles kickham william carleton works tended reflect views middle class gentry wrote came termed novels big house carleton exception ''traits stories irish peasantry'' showed life side social divide bram stoker author ''dracula'' outside traditions early


work lord dunsany one premier ghost story writers nineteenth century sheridan le fanu whose works include ''uncle silas'' ''carmilla'' novels stories mostly humorous edith somerville violet florence martin wrote together martin ross among accomplished products anglo irish literature though written exclusively viewpoint big house published ''the real charlotte'' george moore spent much early career paris one first writers use techniques french realist novelists english oscar


wilde born educated ireland spent latter half life england plays distinguished wit also poet growth irish cultural nationalism towards end th century culminating gaelic revival marked influence irish writing english contributed irish literary revival clearly seen plays jm synge spent time irish speaking aran islands early poetry william butler yeats irish mythology used


barrister revolutionary pioneer modernist literature irish followed among others p draic conaire individualist strongly european bent one finest writers emerge irish time seosamh mac grianna writer powerful autobiography accomplished novels though creative period cut short illness brother amus grianna prolific period also saw remarkable autobiographies remote irish speaking areas south west tom criomhthain peig sayers muiris illeabh


irt n cadhain language activist generally acknowledged doyen difficult modern writers irish compared james joyce produced short stories two novels journalism irt n dire ire mhac tsaoi b se n r ord three finest poets generation eoghan tuairisc wrote irish english noted readiness experiment prose verse flann o'brien northern ireland published irish language novel ''an b al bocht''


name myles na gcopaleen caitl n maude nuala n dhomhnaill b may seen representatives new generation poets conscious tradition modernist outlook best known generation possibly michael hartnett wrote irish english abandoning latter altogether time writing irish encompasses broad range subjects genres attention directed younger readers traditional irish speaking areas gaeltacht less important source authors themes urban irish speakers ascendancy


likely determine nature literature literature ulster scots ulster scots speaking areas traditionally considerable demand work scottish poets allan ramsay robert burns often locally printed editions complemented locally written work prominent rhyming weaver poetry volumes published peak decades ref name rhyming weavers hewitt weaver poets looked scotland cultural literary models


simple imitators clearly inheritors literary tradition following poetic orthographic practices always immediately possible distinguish traditional scots writing scotland ulster ref name robinson among ''rhyming weavers'' james campbell james orr thomas beggs david herbison hugh porter andrew mckenzie scots also used narrative novelists w g lyttle archibald mcilroy middle th century ''kailyard school'' prose become dominant literary genre overtaking poetry


tradition shared scotland continued early th century ref name robinson somewhat diminished tradition vernacular poetry survived th century work poets adam lynn author collection ''random rhymes frae cullybackey'' john stevenson died writing pat m'carty ref name ferguson p ferguson ed ''ulster scots writing'' dublin p ref john clifford east antrim ref name ferguson p prolific writer poet w f marshall may january known bard tyrone marshall composed poems


''hi uncle sam'' ''me an' da'' subtitled ''livin' drumlister'' ''sarah ann'' ''our son'' leading authority mid ulster english predominant dialect ulster polarising effects politics use english irish language traditions limited academic public interest studies john hewitt onwards impetus given generalised exploration non irish non english cultural identities latter decades th century late th century ulster scots poetic tradition revived albeit often replacing traditional


modern scots orthographic practice series contradictory idiolects ref name abdnacuk http wwwabdnacuk riiss reviews falconer frank fergusonshtml gavin falconer review frank ferguson ulster scots writing anthology ref james fenton 's poetry times lively contented wistful written contemporary ulster scots ref name robinson mostly using blank verse form also occasionally habbie stanza ref name robinson employs orthography presents reader difficult combination eye dialect dense scots greater variety verse forms employed hitherto ref name abdnacuk michael longley another poet made use ulster scots work philip robinson 's


writing described verging post modern kailyard ref name ferguson ''ulster scots writing'' ed ferguson dublin ref produced trilogy novels ''wake tribe dan'' ''the back streets claw'' ''the man frae ministry'' well story books children ''esther quaen tha ulidian pechts'' ''fergus tha stane destinie'' two volumes poetry ''alang shore'' ''oul licht new licht'' team belfast begun translating portions bible ulster scots gospel luke published


irish literature english th century james joyce poet w b yeats initially influenced pre raphaelites made use irish peasant folk traditions ancient celtic myth early poetry subsequently drawn intellectually vigorous poetry john donne along ezra pound eliot became one greatest th century modernist poets though yeats anglo irish protestant deeply affected easter rising supported independence ireland received nobel prize literature


member irish senate group early th century irish poets worth noting associated easter rising three republican leadership patrick pearse joseph mary plunkett thomas macdonagh noted poets yeats' earlier celtic mode influential amongst prominent followers early yeats padraic colum f r higgins austin clarke irish poetic modernism took lead yeats joyce saw emergence


generation writers engaged experimental writing matter course best known samuel beckett nobel prize literature beckett 's poetry inconsiderable best known significant second generation modernist irish poets first published include brian coffey denis devlin thomas macgreevy blanaid salkeld mary devenport o'neill yeats followers wrote essentially aristocratic gaelic ireland reality actual


ireland society small farmers shopkeepers inevitably generation poets rebelled example yeats modernist inclination emerged environment patrick kavanagh came small farm wrote narrowness frustrations rural life new generation poets emerged late onward included anthony cronin pearse hutchinson john jordan thomas kinsella based dublin dublin number new literary magazines founded


''poetry ireland'' ''arena'' ''the lace curtain'' ''cyphers'' though novels forrest reid necessarily well known today labelled 'the first ulster novelist european stature' comparisons drawn coming age novel protestant belfast ''following darkness'' james joyce 's seminal novel growing catholic dublin ''a portrait artist young man'' reid 's fiction often uses submerged narratives explore male beauty love placed within historical context emergence


explicit expression homosexuality english literature th century ref name ue ref james joyce one significant novelists first half th century major pioneer use stream consciousness technique famous novel ''ulysses'' ''ulysses'' described demonstration summation entire modernist movement joyce also wrote ''finnegans wake'' ''dubliners'' semi autobiographical ''a portrait artist young man'' ''ulysses'' often considered greatest novel th century


fiction clearly shows mark native tradition particularly imaginative quality storytelling biting edge satire works ''an b al bocht'' samuel beckett nobel prize literature one great figures th century world literature perhaps best known plays also wrote works fiction including ''watt'' trilogy ''molloy'' ''malone dies'' ''the unnamable'' three first written published french big house novel prospered th


century aidan higgins' first novel ''langrishe go down'' experimental example ''genre'' conventional exponents include elizabeth bowen molly keane writing mj farrell rise irish free state republic ireland novelists lower social classes began emerge frequently authors wrote narrow circumscribed lives lower middle classes small farmers exponents style range brinsley macnamara john mcgahern notable novelists late th early st century include john banville sebastian


barry seamus deane dermot healy jennifer johnston patrick mccabe edna o'brien colm ib n william trevor irish short story proved popular genre well known practitioners including frank o'connor se n faol william trevor total four irish writers nobel prize literature wb yeats george bernard shaw samuel beckett seamus heaney literature northern ireland ireland partitioned independent irish free state northern ireland retained constitutional connection united kingdom northern ireland several centuries consisted two distinct communities protestant


ulster scots irish catholics protestants majority emphasise constitutional ties united kingdom catholics would prefer united ireland long standing cultural political division led sectarian violence late known troubles officially ended though sporadic violence continued cultural division created long two distinct literary cultures c lewis louis macneice two writers born raised northern ireland whose careers took england c lewis poet novelist academic medievalist literary critic


included w h auden stephen spender cecil day lewis nicknamed macspaunday group name invented roy campbell ''talking bronco'' body work widely appreciated public lifetime never overtly simplistically political contemporaries work shows humane opposition totalitarianism well acute awareness irish roots macneice felt estranged presbyterian northern ireland voodoo orange bands felt caught british irish identities ref name nonmetropolitan ref derek mahon northern ireland also produced


number significant poets since including john hewitt john montague seamus heaney derek mahon paul muldoon james fenton michael longley frank ormsby ciar n carson medbh mcguckian john hewitt many consider founding father northern irish poetry born belfast began publishing hewitt appointed first writer residence queen 's university belfast collections include ''the day corncrake'' ''out time poems '' ''collected poems'' john montague born new york


brought county tyrone published number volumes poetry two collections short stories two volumes memoir montague published first collection second became first occupant ireland chair poetry ref name ireland chair poetry john montague ref virtually ireland 's poet laureate seamus heaney famous poets came prominence nobel prize heaney longley muldoon others belonged called belfast group heaney


verse translation ''beowulf'' uses words ulster speech catholic northern ireland heaney rejected british identity lived republic ireland much later life james fenton 's poetry written contemporary ulster scots michael longley experimented ulster scots translation classical verse collection ''the ghost orchid'' longley spoken identity northern irish poet time feel british time feel irish time feel


neither marvellous thing good friday agreement allowed feel wanted awarded queen 's gold medal poetry medbh mcguckian 's born maeve mccaughan first published poems appeared two pamphlets year received eric gregory award medbh mcguckian 's first major collection ''the flower master'' awarded rooney prize irish literature ireland arts council award alice hunt bartlett prize also winner cheltenham


prize collection ''on ballycastle beach'' translated english eil n chuillean ''the water horse'' selection poems irish nuala n dhomhnaill among recent collections ''the currach requires harbours'' ''my love fared inland'' paul muldoon published thirty collections pulitzer prize poetry eliot prize held post oxford professor poetry derek mahon 's first collection ''twelve poems'' appeared poetry influenced


louis macneice w h auden often bleak uncompromising though mahon active member belfast group associated two members heaney longley ciar n carson 's poem ''belfast confetti'' aftermath ira bomb ''the irish times'' irish literature prize poetry significant dramatist northern ireland brian friel omagh county tyrone ref name times friel letters exile nightingale benedict http entertainmenttimesonlinecouk tol arts entertainment stage theatre article ece brian friel 's letters internal exile ''the times'' february fuses warmth humour melancholy seamlessly


make worthy birthday gift friel turned justify status one ireland 's seven saoi aosd na meaning wear golden torc round neck officially fans know wise man people art maybe greatest living english language dramatist ref ref name londonderry sentinel bidding http wwwlondonderrysentinelcouk news local londonderry beats norwich sheffield birmingham bidding punch londonderry beats norwich sheffield birmingham bidding punch ''londonderry sentinel'' may ref ref name seeing brian friel 's ballybeg canby vincent http theaternytimescom mem theater treviewhtmlres e db f ba c seeing brian friel 's ballybeg ''the new york times'' january brian


friel recognized ireland 's greatest living playwright almost since first production philadelphia come dublin succeeding years dazzled us plays speak language unequaled poetic beauty intensity dramas translations dancing lughnasa wonderful tennessee among others given privileged place theater ref hailed english speaking world irish chekhov ref name three flavors emotion aristocrats winer linda https pqasbpqarchivercom newsday access htmldids fmt abs fmts abs ft type current date jul c author linda winer staff writer pub newsday combined editions desc three flavors emotion friel 's old ballybeg pqatl google three flavors emotion friel 's old ballybeg ''newsday'' july us never quite understood brian friel called


irish chekhov aristocrats explain actually justify compliment ref universally accented voice ireland ref name friel furrow heart o'kelly emer http wwwindependentie incoming friels deep furrow cuts heart html friel 's deep furrow cuts heart ''sunday independent'' september ref friel best known plays ''philadelphia come '' ''dancing lughnasa'' written thirty plays six decade spanning career seen elected saoi aosd na plays regular feature broadway among important novelists northern ireland flann o'brien brian moore bernard


maclaverty flann o'brien brian o'nolan novelist playwright satirist considered major figure twentieth century irish literature born strabane county tyrone also regarded key figure postmodern literature english language novels ''at swim two birds'' ''the third policeman'' written ''nom de plume'' flann o'brien many satirical columns ''the irish times'' irish language novel ''an b al bocht'' written name myles na gcopaleen o'nolan 's novels attracted wide following bizarre humour modernist metafiction


explorations inter communal divisions troubles awarded james tait black memorial prize inaugural sunday express book year award shortlisted booker prize three times novel ''judith hearne'' set belfast bernard maclaverty belfast written novels ''cal'' ''lamb'' describes experiences young irish catholic involved ira ''grace notes'' shortlisted booker prize ''the anatomy school'' also written five acclaimed collections


short stories recent ''matters life death'' lived scotland since noteworthy writers northern ireland include poet robert greacen novelist bob shaw ref name shaw ref science fiction novelist ian mcdonald robert greacen along valentin iremonger edited important anthology ''contemporary irish poetry'' robert greacen born derry lived belfast youth london irish times prize poetry ''collected poems'' subsequently moved


dublin elected member ''aosdana'' shaw science fiction author noted originality wit hugo award best fan writer short story light days hugo award nominee novel ''the ragged astronauts'' theatre george bernard shaw first well documented instance theatrical production ireland staging ''gorboduc'' presented lord mountjoy lord deputy ireland great hall dublin castle mountjoy started fashion private performances became


''she stoops conquer'' richard brinsley sheridan known ''the rivals'' ''the school scandal'' goldsmith sheridan two successful playwrights london stage th century th century dion boucicault famed melodramas later part th century boucicault become known sides atlantic one successful actor playwright managers english speaking theatre ''the new york times'' heralded obituary conspicuous english dramatist th century


last decade century irish theatre came age establishment dublin irish literary theatre emergence dramatists george bernard shaw oscar wilde though wrote london theatre shaw 's career began last decade nineteenth century wrote plays george bernard shaw turned edwardian theatre arena debate important political social issues like marriage class morality armaments war rights women number


playwrights actors staff several companies went form irish national theatre society later become abbey theatre performed plays wb yeats lady gregory john millington synge se n o'casey equally importantly introduction yeats via ezra pound elements noh theatre japan tendency mythologise quotidian situations particularly strong focus writings dialects hiberno english abbey create style held strong fascination future irish dramatists synge 's famous play ''the playboy


western world'' caused outrage riots first performed dublin o'casey committed socialist first irish playwright note write dublin working classes o'casey 's first accepted play ''the shadow gunman'' set irish war independence performed abbey theatre followed ''juno paycock'' ''the plough stars'' former deals effect irish civil war working class poor city latter set


dublin around easter rising gate theatre founded miche l macliamm ir introduced irish audiences many classics irish european stage twentieth century saw number irish playwrights come prominence included denis johnston samuel beckett brendan behan hugh leonard john b keane brian friel thomas kilroy tom murphy frank mcguinness denis johnston 's famous plays ''the old lady says '' ''the moon yellow river''


doubt samuel beckett irishman lived much life france wrote several works first french famous plays ''waiting godot'' originally ''en attendant godot'' ''endgame'' originally ''fin de partie'' ''happy days'' written english profoundly affected british drama samuel beckett painted reginald gray life paris behan 's first play ''the quare fellow'' produced dublin well received however production joan littlewood 's theatre workshop stratford london


gained behan wider reputation helped famous drunken interview bbc television behan 's play ''the hostage'' english language adaptation play irish ''an giall'' met great success internationally hugh leonard first major irish writer establish reputation television writing extensively television including original plays comedies thrillers adaptations classic novels british television ref name fintan o'toole writing death hugh leonard ref commissioned rt write insurrection th anniversary dramatic reconstruction irish uprising


easter leonard 's ''silent song'' adapted bbc short story frank o'connor prix italia ref name prix italia winners ref three leonard 's plays presented broadway ''the au pair man'' starred charles durning julie harris ''da'' ''a life'' ''da'' originated broadway hudson guild theatre transferring morosco theatre successful running months performances touring united states ten months earned leonard tony award drama desk award


best play made film brian friel northern ireland recognised major irish english language playwright almost since first production philadelphia come dublin tom murphy major contemporary playwright honoured abbey theatre retrospective season six plays plays include historical epic ''famine'' deals great famine spring ''the sanctuary lamp'' ''the gigli concert'' ''bailegangaire'' frank mcguinness first


came prominence play ''the factory girls'' established reputation play world war ''observe sons ulster marching towards somme'' staged dublin 's abbey theatre internationally play made name performed hampstead theatre numerous awards including london evening standard award promising playwright mcguinness since number companies emerged challenge abbey 's dominance introduce different styles approaches include focus theatre children 's company project


theatre company druid theatre rough magic team charabanc field day companies nurtured number writers actors directors since gone successful london broadway hollywood irish language theatre conventional drama exist irish th century gaelic revival stimulated writing plays aided founding taibhdhearc theatre dedicated irish language abbey theatre reconstituted bilingual national theatre ernest blythe irish language element declined importance


behan 's play irish language ''an giall'' debut dublin 's damer theatre later english language adaptation ''an giall'' ''the hostage'' met great success internationally drama irish since encountered grave difficulties despite existence interesting playwrights ir ad n ghr da taidhbhearc declined importance difficult maintain professional standards absence strong lively audience tradition persists however thanks troupes like aisling gh ar see also footnotes references brady anne cleeve brian ''biographical dictionary irish writers'' lilliput educational media solutions


p draig ''foras feasa ar irinn athnua '' foilseach n isi nta teoranta baile tha cliath two volume version keating 's history modernised spelling crosson se n 'the given note' traditional music modern irish poetry cambridge scholars publishing dublin overview historical relationship poetry music ireland de bhaldraithe tom ed third printing ''c n lae amhlaoibh'' cl chomhar tta baile tha cliath shortened version diaries amhlaoibh illeabh english translation edited de bhaldraithe ''diary irish countryman


'' mercier press de br n p draig buachalla breand n concheanainn tom second printing ''nua dhuanaire cuid '' institi id ardl inn bhaile tha cliath dillon myles chadwick nora ''the celtic realms'' cardinal london pp nbsp williams ja ed ''pairlement chloinne tom is'' dublin institute advanced studies dublin knott eleanor second printing ''an introduction irish syllabic poetry period '' dublin institute advanced studies dublin merriman brian huaithne ith ed fourth printing ''c irt mhe n che'' preas dolmen baile tha cliath mac aonghusa proinsias 'an ghaeilge


meirice ' ''go meirice siar'' stiof n hannrach ed cl chomhar tta mac h il se n '' liad h im ar'' ficina typofographica gaillimh nicholls kenneth ''gaelic gaelicised ireland middle ages'' gill macmillan dublin conluain proinsias c ileachair donncha second printing ''an duinn neach'' irs al agus dill driscoll robert ''an ascendancy heart ferguson beginnings modern irish literature english'' dolmen press dublin h g ith ''an file'' oifig tsol thair baile tha cliath madag breand n second edition ''an ghaeilge luimneach '' cl chomhar


basrelief sculpture research holding torch knowledge ''olin levi warner'' library congress thomas jefferson building washington dc '''research''' creative systematic work undertaken increase stock knowledge involves collection organization analysis information increase understanding topic issue research project may expansion past work field test validity instruments procedures experiments research may replicate elements prior projects project whole primary purposes basic research opposed applied research

Applied science
Library and museum studies
Research methods


documentation discovery interpretation research development r methods systems advancement human knowledge approaches research depend epistemologies vary considerably within humanities sciences several forms research scientific humanities artistic economic social business marketing practitioner research life technological etc scientific study research practices known meta research etymology aristotle bc one early figures development scientific method word ' 'research'' derived middle french ' 'recherche'' means go seeking term


derived old french term ' 'recerchier'' compound word cerchier sercher meaning 'search' ref name merriam webster ref earliest recorded use term ref name merriam webster definitions research defined number different ways similarities appear single encompassing definition embraced engage one definition research used oecd creative systematic activity undertaken order increase stock knowledge including knowledge man culture society use