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《Physics Reports 1991 59-108Dynamical symmetry breaking in four-fermion interaction models1》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。
1、SLAC-PUB-5349September1990T/EDynamicalSymmetryBreakinginFour-FermiInteractionModels*B.ROSENSTEINUniversityofBritishColumbiaVancouver,CanadaV6T2A6andBRIANJ.WARRStanfordLinearAcceleratorCenterStanfordUniversity,Stanford,California94309andS.H.PARKInternatio
2、nalCentreforTheoreticalPhysicsTrieste,ItalyABSTRACTDynamicalsymmetrybreakingin4-fermionmodelsin2+1dimensionsisquan-titativelystudied.Weusethel/Nexpansionandshowthatthesemodelsarerenormalizableinthisframework,inspiteoftheirnon-renormalizabilityinweakcoupl
3、ingexpansion.Theparticulartopicsdiscussedincludeinteractionsofcom-positeGoldstonebosonswithotherparticlesandamongthemselves,low-energytheorems,chirallagrangians,theeffectsofexplicitsymmetrybreaking,andthethermodynamicsofthedynamicalsymmetryrestoringphase
4、transition.SubmittedtoPhysicsReports*WorksupportedbytheDepartmentofEnergy,contractDE-AC03-76SF00515.1.IntroductionThebreakingofcontinuoussymmetriesinQuantumFieldTheoryisoneofthemostimportantbasicphenomenainmodernphysics.Thisideaoriginatedinthetheoryofcon
5、densedmatter[l]b-utiswidelyusedintherealmofelementaryparticles.Heresymmetrybreakingprovidesthebasisforourunderstandingoftwoconcreteareasofphenomenology:theunificationofweakandelectromagneticforcesintheStandardModel[24],andthelow-energyscatteringofpionsan
6、dnucleons[5,6].SymmetrybreakingalsoplaysacrucialroleinattemptstogobeyondtheStandardModel,suchasGrandUnifiedTheories[7]and“Technicolor”PI.Thesymmetrybreakingphenomenonisexhibitedbyanon-zeroexpectationvalueforsomenon-singletfieldoperatorknownasthe“orderpar
7、ameter.”Inthecaseswherethisorderparameterislinearintheelementaryfieldsthe“classicalapproximation”totheactionisanappropriateone,andtheweakcoupling(smalltL)expansioncanyieldareliablecalculationalscheme.Thisiswhatobtainsintheelectro-weaktheory:theclassicalp
8、otentialforthescalarHiggsfieldshasamaximumattheorigin,and(inagauge-fixedformalism)oneshiftsthefieldstooneoftheminima.Crucially,theHiggs-Kibblemechanism[9]canbeseenalreadyatthislevelofanalysis,providingmassesfortheWand2’bos
