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1、SHEP–96–33DEVELOPMENTINLATTICEQCDJONATHANMFLYNNDepartmentofPhysics,UniversityofSouthampton,High?eld,Southampton,SO171BJ,UKAfterabriefdiscussionofthepromiseandlimitationsofthelatticetechnique,IreviewlatticeQCDresultsforseveralquantitiesofphenomenologicalinterest.Theseare:matri
2、xelementsforheavy-to-lightmesondecays,leptonicdecayconstantsfBandfD,theparametersBBandBKforneutralBandKmesonmixingrespectively,thestrongcouplingconstant,lightquarkmassesandthelightestscalarglueballmass.1Introductiondynamics.Continuumresultsshouldbeobtainedinthelimita→0:thisco
3、ntinuumextrapolationisnowInthisreviewIconcentrateonlatticeQCDresultsfeasibleformanyquantities.Latticesshouldbelargeforaselectionofquantitiesdirectlyrelevantforphe-enoughthathadronswillcomfortably?tonthem.nomenology,someofwhichwerenototherwisere-Currentspatialsizesareoforder2f
4、morso,thoughportedatthisconference.Iapologisetopresenterssomepractitionersadvocateatleast2.5fm.1oflatticestudieswhichIdonothavespacetoreportBecausetheQCDactionisquadraticinthequarkonhereandrefertheinterestedreaderdirectlytothe?elds,matrixelementsofquarkscanbeevaluatedus-paral
5、lelsessionreports.ingquarkpropagatorsinthegluonbackgroundto-LatticeQCDisanimportanttoolforthenon-getherwiththegluon-?eld-dependentdeterminantofperturbativeevaluationofstronginteractione?ects,thefermionoperator.Thedeterminantisextremelybutawaryconsumershouldkeepinmindthemainde
6、mandingtocalculatesoitisoftensettoitsaveragesourcesoferror,whichIwillbrie?ymentionbelow,valueinthegauge?eldbackground—thequenchedwhenusinglatticeresults.Onebeautyofthelatticeapproximation—whichcorrespondstoneglectingin-approachisthattheseerrorscanbesystematicallyternalquarklo
7、ops.Inpractice,muchofthee?ectinvestigatedandreduced.ofinternalloopsistochangetherunningofthecou-Thepresentationbeginswithformfactorsforplingconstantandthiscanbecompensatedbychang-Bˉ0→π+l?νˉ,Bˉ0→ρ+l?νˉandBˉ→K?γ.Thesemilep-llingthevalueofβ,thebarecouplingwhichisinput.tonicdecay
8、sareimportantfordetermining
9、Vub
10、;theQuenchingisoneofthesystematice?e
