简介:TheextendedcanonicalNoetheridentitiesandcanonicalfirstNoethertheoremderivedfromanextendedactioninphasespaceforasystemwithasingularLagrangianareformulated.UsingthesecanonicalNoetheridentities,itcanbeshownthattheconstraintmultipliersconnectedwiththefirst-classconstraintsmaynotbeindependent,soaquerytoaconjectureofDiracispresented.BasedonthesymmetrypropertiesoftheconstrainedHamiltoniansysteminphasespace,acounterexampletoaconjectureofDiracisgiventoshowthatDirac'sconjecturefailsinsuchasystem.WepresenthereadifferentwayratherthanCawley'sexamplesandother'sonesinthatthereisnolinearizationofconstraintsintheproblem.Thisexamplehasafeaturethatneithertheprimaryfirst-classconstraintsnorsecondaryfirst-classconstraintsaregeneratorsofthegaugetransformation.
简介:Anexplicitlysolvablemodelfortunnellingofrelativisticspinlessparticlesthroughasphereissuggested.ThemodeloperatorisconstructedbyanoperatorextensionstheorymethodfromtheorthogonalsumoftheDiracoperatorsonasemiaxisandonthesphere.Thetransmissioncoefficientisobtained.Thedependenceofthetransmissioncoefficientontheparticleenergyhasaresonantcharacter.OneobservespairsoftheBreit–WignerandtheFanoresonances.Itcorrelateswiththecorrespondingresultsforanon-relativisticparticle.
简介:明确的Bargmann对称限制被计算,它宽松的对的联系二进制nonlinearization为超级迪拉克系统被执行。在获得的对称限制下面,超级迪拉克层次的第n流动被分解成二个超级有限维的integrableHamiltonian系统,定义在上超级对称歧管有相应动态变量的R4N|2Nx和tn。运动的积分为Liouville要求integrability明确地被给。关键词对称限制-二进制nonlinearization-超级迪拉克系统-超级有限维的integrableHamiltonian系统2000苏布杰克特先生分类35Q51-37J35-37K10-37K40工程由Hangdian基础支持了(没有。KYS075608072),中国的国家自然科学基础(Nos.10671187,10971109)并且为中国的大学里的新世纪优秀才能的程序(没有。NCET-08-0515)。
简介:TheneuralnetworkrealtimeeventselectionfortheDIRACewperimentatCERNispresented.Itcomprisesoftwoindependentparts.OneusesplasticscintillatorsandtheothertheverticalScintillatingFibres,Theglobaleventdecisionistakeninlessthan250ns.Signaleventsareselectedwithanefficiencyosmorethan0.99withabackgroundratereductionofabout2.
简介:Asamanifestationoftheunderlyingphysicalnature,quailtumoscillationswiththeappliedmagneticfield(B)areoneofthemostimportanttopicsincondensedmatterphysics.Theresearchhistorycanbetrackedto1930whenLevShubnikovandW.J.deHaasobservedShubnikov-deHaas(SdH)oscillationsinthemagnetoresistance(MR)ofbismuthcrystals.Sincethen,researchershaveobservedquantumoscillationsindiversematerials,includingmetals,metalliccompounds,semimetals,semiconductorsandeveninsulators,aswellasinartificialmesoscopicmicrostructures.Nowadays,quantumoscillationdetectedbymagnetotransportinvestigationhasbeenapowerfultooltodetectthephysicalpropertiesinsolid-statesystems.
简介:Inthispaper,westudysymmetryreductionforabinaryasteroidsystemmodeledbyarigidbodyandaparticle.Inparticular,wedemonstratehowtranslationalandrotationalsymmetryreductionappearedinthebinaryasteroidsystemcanbecarriedoutinthecontextofDiracreductionbystagesandwiththeassociatedreductionofimplicitHamiltoniansystems.Thenweinvestigatestabilityofrelativeequilibriaoftheasteroidpairandshowstabilityregionsbyusingtheenergy-momentummethod.Lastly,weillustratesomenumericalsimulationsforstableandunstableorbitsnearfromrelativeequilibriaoftheCollinearandTconfigurations.
简介:分离香农熵被使用在multiconfigurationDiracFockwavefunction描述信息。香农熵的依赖作为扩大配置空间被显示出,它能到达浸透什么时候有足够的配置状态wavefunctions获得会聚的精力层次;也就是说,在multiconfigurationDiracFock方法的计算过程是一个熵浸透过程。在一样的精确性水平,为最小的熵的基础集合是能描述精力状态的最好。另外,在与等电子的顺序一起的香农信息熵和精力水平十字路口的突然的变化之间的一个连接能被建立,它是有用的发现精力对为X光激光解释并且预见精力层次的倒置计划的兴趣的水平十字路口。
简介:Ingraphene,conductanceelectronsbehaveasmasslessrelativisticparticlesandobeyananalogueoftheDiracequationintwodimensionswithachiralnature.Forthisreason,theboundingofelectronsingrapheneintheformofgeometriesofquantumdotsisimpossible.Ingaplessgraphene,duetoitsuniqueelectronicbandstructure,thereisaminimalconductivityatDiracpoints,thatis,inthelimitofzerodoping.Thiscreatesaproblemforusingsuchahighlymotivatednewmaterialinelectronicdevices.Oneofthewaystoovercomethisproblemisthecreationofabandgapinthegraphenebandstructure,whichismadebyinversionsymmetrybreaking(symmetryofsublattices).WeinvestigatetheconfinedstatesofthemasslessDiracfermionsinanimpuredgraphenebytheshort-rangeperturbationsfor"localchemicalpotential"and"localgap".Thecalculatedenergyspectrumexhibitsquitedifferentfeatureswithandwithouttheperturbations.Acharacteristicequationforboundstates(BSs)hasbeenobtained.Itissurprisinglyfoundthattherelationbetweentheradialfunctionsofsublatticeswavefunctions,i.e.,f_m~+(r),g_m~+(r),andf_m~-(r),g_m~-(r),canbeestablishedbySO(2)group.
简介:<正>AneffectiverelativisticcontinuummassiveProcaLagrangianactionisusedtoaccountfortheLorentzvectorcondensationeffectsontheequationofstateofthestronglyinteractingfermionssystem.TheinteriorquantumfluctuationeffectsareincorporatedasanexternalfieldapproximationindirectlythroughafictivegeneralizedThomsonProblemcountertermbackground.Thegeneralanalyticalformulasforthed-dimensionalthermodynamicsaregivenneartheunitarylimitregion,Inthenon-relativisticlimitford=3,theuniversaldimensionlesscoefficientε=4/9andenergygap△/ε_f=5/18arereasonablyconsistentwiththeexistingtheoreticalandexperimentalresults.Intheunitarylimitford=2andT=0,theuniversalcoefficientcanevenapproachtheextremeoccasionξ=0correspondingtotheinfiniteeffectivefermionmassm~*=∞,whichcanbemappedtothestronglycoupledtwo-dimensionalelectronsandisquitesimilartothethree-dimensionalBose-Einsteincondensationofidealbosongas.Instead,ford=1,theuniversalcoefficientξisnegative,implyingthenon-existenceofphasetransitionfromsuperfluiditytonormalstate.ThesolutionsmanifestthequantumIsinguniversalclasscharacteristicofthestronglycoupledunitaryfermionsgas.
简介:本文引入了偶数维欧氏空间的复结构及Witt基,在此基础上讨论了偶数维复Clifford代数中的Dirac旋量空间.由Fock空间的结果我们得到了Dirac旋量空间视为复Clifford代数中极小左理想,最后我们研究了Dirac旋量空间的对偶空间.
简介:Adoptingthecharge-dependentArgonneV_(18)plusmicroscopicthree-bodyforces,theequationofstate(EOS)andsingleparticlepropertiesofsymmetricnuclearmatterhavebeeninvestigatedinBrueckner-Hartree-Fock(BHF)framework~[1].Themicroscopicthree-bodyforcemodel