StephenWilliamHawking,CH,CBE,FRS,FRSA(born8January1942)isaBritishtheoreticalphysicist.Heisknownforhiscontributionstothefieldsofcosmologyandquantumgravity,especiallyinthecontextofblackholes.Hehasalsoachievedsuccesswithworksofpopularscienceinwhichhediscusseshisowntheoriesandcosmologyingeneral;theseincludetherunawaybestsellerABriefHistoryofTime,whichstayedontheBritishSundayTimesbestsellerslistforarecord-breaking237weeks. 　　Hawking'skeyscientificworkstodatehaveincludedproviding,withRogerPenrose,theoremsregardingsingularitiesintheframeworkofgeneralrelativity,andthetheoreticalpredictionthatblackholesshouldemitradiation,whichistodayknownasHawkingradiation(orsometimesasBekenstein-Hawkingradiation).Heisaworld-renownedtheoreticalphysicistwhosescientificcareerspansover40years.Hisbooksandpublicappearanceshavemadehimanacademiccelebrity.HeisanHonoraryFellowoftheRoyalSocietyofArts,andalifetimememberofthePontificalAcademyofScience.OnAugust12,2009,hewasawardedthePresidentialMedalofFreedom,thehighestcivilianawardintheUnitedStates. 　　HawkingistheLucasianProfessorofMathematicsattheUniversityofCambridge(butintendstoretirefromthispostin2009),aFellowofGonvilleandCaiusCollege,CambridgeandthedistinguishedresearchchairatWaterloo'sPerimeterInstituteforTheoreticalPhysics. 　　Hawkinghasaneuromusculardystrophythatisrelatedtoamyotrophiclateralsclerosis(ALS),aconditionthathasprogressedovertheyearsandhaslefthimalmostcompletelyparalysed.