AlbertEinsteinAlbertEinsteinwasbornatUlm,inWürttemberg,Germany,onMarch14,1879.SixweekslaterthefamilymovedtoMunichandhebeganhisschoolingthereattheLuitpoldGymnasium.Later,theymovedtoItalyandAlbertcontinuedhiseducationatAarau,Switzerlandandin1896heenteredtheSwissFederalPolytechnicSchoolinZurichtobetrainedasateacherinphysicsandmathematics.In1901,theyearhegainedhisdiploma,heacquiredSwisscitizenshipand,ashewasunabletofindateachingpost,heacceptedapositionastechnicalassistantintheSwissPatentOffice.In1905heobtainedhisdoctor'sdegree.DuringhisstayatthePatentOffice,andinhissparetime,heproducedmuchofhisremarkableworkandin1908hewasappointedPrivatdozentinBerne.In1909hebecameProfessorExtraordinaryatZurich,in1911ProfessorofTheoreticalPhysicsatPrague,returningtoZurichinthefollowingyeartofillasimilarpost.In1914hewasappointedDirectoroftheKaiserWilhelmPhysicalInstituteandProfessorintheUniversityofBerlin.HebecameaGermancitizenin1914andremainedinBerlinuntil1933whenherenouncedhiscitizenshipforpoliticalreasonsandemigratedtoAmericatotakethepositionofProfessorofTheoreticalPhysicsatPrinceton*.HebecameaUnitedStatescitizenin1940andretiredfromhispostin1945.AfterWorldWarII,EinsteinwasaleadingfigureintheWorldGovernmentMovement,hewasofferedthePresidencyoftheStateofIsrael,whichhedeclined,andhecollaboratedwithDr.ChaimWeizmanninestablishingtheHebrewUniversityofJerusalem.Einsteinalwaysappearedtohaveaclearviewoftheproblemsofphysicsandthedeterminationtosolvethem.Hehadastrategyofhisownandwasabletovisualizethemainstagesonthewaytohisgoal.Heregardedhismajorachievementsasmerestepping-stonesforthenextadvance.Atthestartofhisscientificwork,EinsteinrealizedtheinadequaciesofNewtonianmechanicsandhisspecialtheoryofrelativitystemmedfromanattempttoreconcilethelawsofmechanicswiththelawsoftheelectromagneticfield.Hedealtwithclassicalproblemsofstatisticalmechanicsandproblemsinwhichtheyweremergedwithquantumtheory:thisledtoanexplanationoftheBrownianmovementofmolecules.Heinvestigatedthethermalpropertiesoflightwithalowradiationdensityandhisobservationslaidthefoundationofthephotontheoryoflight.InhisearlydaysinBerlin,Einsteinpostulatedthatthecorrectinterpretationofthespecialtheoryofrelativitymustalsofurnishatheoryofgravitationandin1916hepublishedhispaperonthegeneraltheoryofrelativity.Duringthistimehealsocontributedtotheproblemsofthetheoryofradiationandstatisticalmechanics.Inthe1920's,Einsteinembarkedontheconstructionofunifiedfieldtheories,althoughhecontinuedtoworkontheprobabilisticinterpretationofquantumtheory,andheperseveredwiththisworkinAmerica.Hecontributedtostatisticalmechanicsbyhisdevelopmentofthequantumtheoryofamonatomicgasandhehasalsoaccomplishedvaluableworkinconnectionwithatomictransitionprobabilitiesandrelativisticcosmology.Afterhisretirementhecontinuedtoworktowardstheunificationofthebasicconceptsofphysics,takingtheoppositeapproach,geometrisation,tothemajorityofphysicists.