Noether Symmetries / Theorem  

In General > s.a. hamiltonian and lagrangian symmetries / symmetries.
* Idea: Exploit a symmetry of a theory so as to reduce the number of variables needed to treat a problem.
* History: Soon after Hilbert's discovery of the variational principle for general relativity, people including Hilbert, Klein, and Einstein were concerned about the failure of local energy conservation in the theory; Noether's theorems solved the problem.
$ Def: To every continuous symmetry Δxa = Xab δωb, Δφ = Φa δωa of the Lagrangian for a field theory there corresponds a conserved current J ab with ∂a J ab = 0, and a conserved quantity, the charge Qb:

J ab:= (∂/∂(∂aφ)) Φbθ ac X cb ,   Qb:= Σ dSa J ab.

@ General references: Noether NKGG(18) [translation TTSP(71)phy/05]; Govinder & Leach PLA(95) [integrals]; Byers phy/98 [historical]; Fatibene et al a1001 [and covariant conservation laws, rev]; Neuenschwander 11; Tsamparlis & Paliathanasis GRG(11) [geometric nature]; Francaviglia et al a1309-conf [epistemological implications]; Neuenschwander AJP(14)mar [in the undergraduate curriculum].
@ Second theorem: Gogilidze & Surovtsev ht/96 [and constraints]; Bashkirov et al JPA(05)m.DG/04 [generalized setting], JMP(05)mp/04 [BRST symmetries]; Cariñena et al m.DG/05 [gauge symmetries in classical mechanics].
@ And Killing vectors: Bokhari & Kara GRG(07); Hussain GRG(10).
@ Quantum version: Brown & Holland AJP(04)jan [first theorem, and electromagnetism]; Albeverio et al JMP(06); Lima et al AP(12)-a0912 [for gauge theories with anomalies].
@ Related topics: García & Pons IJMPA(01)ht/00 [canonical realization]; Sanyal & Modak CQG(01)gq [and field couplings]; Butterfield phy/05-fs; Bokhari et al IJTP(06) [and spacetime isometries]; Bering a0911-proc [proof, for a fixed integration region]; Dallen & Neuenschwander AJP(11)mar [in a rotating frame]; Pons JMP(11) [energy-momentum tensors and conformal symmetry]; Struckmeier JPCS-a1206 [generalization to Hamiltonian dynamics].

In Specific Theories > s.a. energy-momentum tensor; quantum theory in curved spaces.
@ Classical mechanics: Desloge & Karch AJP(77)apr; Sardanashvily mp/03; Marinho EJP(07), comment Rejmer EJP(09); > s.a. classical particles.
@ Gauge theories / quantum field theories: Buchholz et al AP(86); Karatas & Kowalski AJP(90)feb; Danos FP(97)ht; Fatibene et al JMP(97); Julia & Silva CQG(98)gq; Gràcia & Pons JMP(00)mp; Bashkirov JPA(05) [reducible gauge symmetries]; Darvas a0811 [new conserved current].
@ In gravitation: Sorkin PRS(91) [Noether operator, and electromagnetism]; Majhi & Padmanabhan PRD(12), Majhi AHEP(13)-a1210 [Noether charge from Einstein-Hilbert action, and Bekenstein-Hawking entropy]; Petrov & Lompay GRG(13)-a1211 [metric theories of gravity].
@ In cosmological models: Vakili PLB(08)-a0804; Paliathanasis et al PRD(14) [scalar-tensor cosmology]; > s.a. minisuperspace models.
@ Other applications: García & Pons IJMPA(00)ht/99 [constrained systems]; Hanc et al AJP(04)apr [examples and teaching].

Generalizations
@ General references: Rosen AP(72), AP(74), AP(74); Torres m.OC/03-conf [non-smooth solutions]; Fassò & Sansonetto IJGMP(09) [non-holonomic]; Hydon & Mansfield PRS(11)-a1103 [simple local proof and extension to finite-difference systems]; Marvian & Spekkens Nat-a1404 [quantifying the asymmetry of quantum states].
@ More general type of symmetries: Lunev TMP(90) [non-local symmetries]; Govinder et al PLA(98) [approximate symmetries]; Paal in(09)mp/06, CzJP(06)mp-conf [from Moufang transformations]; Agostini et al MPLA(07)ht/06, Arzano & Marcianò PRD(07)ht, Amelino-Camelia et al PTPS(07)-a0710-conf [for Hopf-algebra spacetime symmetries]; Cicogna & Gaeta JPA(07) [for μ-symmetries]; Alamino a1305 [symmetry on average, and Noether's theorem with dissipative currents]; Webb & Mace a1403 [fluid relabelling symmetries].
@ More general types of theories: Cariñena & Rañada LMP(88) [singular Lagrangians]; Gràcia & Pons JPA(95) [higher-order Lagrangians]; Magro et al AP(02)ht/01 [superfields]; Holman a1009 [for field theories formulated in Minkowski spacetime]; Baez & Fong JMP(13)-a1203 [for Markov Processes].
@ Non-Lagrangian theories: Kaparulin et al JMP(10)-a1001; Delphenich a1109 [based on the virtual work functional].
@ More general settings: Agostini IJMPA(09)-a0711 [in κ-Minkowski]; Muslih a1003 [for fractional classical fields].


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