Measurement in Quantum Theory  

In General > s.a. Born Rule; Measurement; observables; experiments in physics.
* Measurement problem: Understanding the reduction of the wave packet of a microsystem and the specification of its quantum state (wave-function collapse) by a macroscopic measuring instrument; The incompatibility of wave function collapse and unitarity.
* Approaches: Some types of approaches are (a) The collapse of the wave function, as [i] a non-linear physical process by which at the time of measurement the wave-function collapses into one of the possible alternatives, which requires that quantum mechanics be modified from its present form or [ii] as an effective process due to decoherence; (b) The many-worlds interpretation, which asserts that at the time of measurement the Universe splits into many branches, one for every possible alternative, and does not require any modification of quantum mechanics; The various branches do not interfere with each other because of decoherence; (c) Quantum Bayesianism (QBism), according to which the change in the quantum state is not in the physical system.
* Formalism: In simple cases probabilities of various results are obtained using the Born rule, but in realistic experiments must berepresented by positive operator-valued measures (POVMs).
* History: V Fock and S Ludwig thought that apparata should be treated classically, but then the probabilistic outcome of experiments cannot be described; J Bell advocated using the word "experiment" instead of "measurement".
* Landau-Lifshitz conjecture: Relationship with second law of thermodynamics.
* Issues: Which measurements can be consistently performed? Some lead to acausal properties [@ Sorkin in(90)].

And Relativity > s.a. causality; collapse of the wave function; relativistic quantum mechanics; spacetime; spacetime topology.
@ Lorentz invariance: Bloch PR(67); Pitowsky PLA(91) [observer dependence of predictions]; Droz-Vincent FP(95); Mensky & von Borzeszkowski PLA(95)qp/00 [measurement of electromagnetic field]; Marolf & Rovelli PRD(02)gq [detector and localization].
@ And causality: Zanchini & Barletta NCB(91); Moffat gq/97; Svetlichny FP(03) [detectors and collapse]; Gambini & Porto NJP(03)qp/02; Gillis FP(11)-a1007.
@ Quantum gravity: Menskii in(85); Ahluwalia PLB(94)gq/93; González-Díaz IJTP(98)qp/97; Anandan FP(99)gq/98; Percival PRS(00)qp/98 [cosmic "measurement field"]; Hadley IJTP(99) [effect of geons]; Nomura a1110 [and cosmological dynamics].

In Quantum Field Theory > s.a. QED; quantum field theory phenomenology.
@ General references: in Heitler 54; Aharonov et al PRD(86); Danos & Kieu IJMPE(99)qp/97; Gambini & Porto NJP(02)qp [realistic interpretation]; Rubin FP(11)-a0909 [in many-worlds interpretation]; Dressel et al PRL(14)-a1308 [quantum weak measurement protocol]; Anastopoulos & Savvidou a1509, a1509.
@ Electromagnetic field: Bohr & Rosenfeld KDVS(33), PR(50); Menskii TMP(89); von Borzeszkowski & Mensky PLA(94)qp/00.
@ In curved spacetime: Fewster & Verch a1810; Fewster a1904-proc [generally covariant].
@ And quantum gravity: Gadiyar ht/01 [and volume quantization]; von Borzeszkowski et al FP(02); Oeckl CQG(03).
@ Related topics: Sorkin gq/93-proc [impossible measurements]; Álvarez-Estrada & Sánchez-Gómez PLA(99)qp/98 [decay, no Zeno effect]; Bostelmann et al PRD(21)-a2003 [impossible measurements]; > s.a. Machine Learning.

Related Topics > s.a. quantum states; realism; time in quantum mechanics; types of quantum measurement; Wigner-Araki-Yanase Theorem.
@ Intrinsic measurement theory: Zurek PRD(81), PRD(82); Deutsch IJTP(85); Allahverdyan et al PhyE(05)qp/04-conf [full hamiltonian model].
@ Role of entanglement: D'Ariano et al qp/01; Busch IJTP(03); Macdonald IJTP(03); Maccone PRA(13)-a1304 [quantum-enhanced precision measurements].
@ And observers: Singh & Whitaker AJP(82)oct [and decays]; Albert PLA(83) [self-description]; Mould FP(95) ["inside" observers]; Squires qp/96, d'Espagnat FP(05)qp/04 [consciousness]; Rosenblum & Kuttner FP(02); Thaheld qp/07; Reason a1707, Broka a1911 [consciousness].
@ And algebras / logic: Pulmannová JMP(94); Lehmann et al IJTP(06)qp/05.
@ Phase-space formulation: Dragoman PS(05)qp/04; Carmeli et al JPA(04)qp; Mello & Revzen PRA(14)-a1307 [Wigner function and successive measurements].
@ Post-measurement state: Audretsch et al PRA(03)qp/02; Laura & Vanni IJTP(08) [using conditional probabilities].
@ Reversibility / undoing: Peres AJP(74)oct; Peres FP(88); Svozil in(98)-a0904 [reversible automata]; van Enk & Raymer a0901/AJP [and reliability]; Schindler et al PRL(13)-a1211; Garner & Vedral a1604 [ultimate physical limits].
@ And thermodynamics: Erez a1011; Hormoz PRE(13)-a1203 [quantum collapse and the second law]; Jacobs PRE(12) [intrinsic energy cost of measurement]; Kastner Ent(17)-a1612 [in the transactional interpretation]; Bera & Bera a1910 [almost without collapse].
@ Models: Peres & Rosen AP(64) [classical test-body model]; Busch & Lahti FP(96)qp [and history]; Allahverdyan et al cm/03-conf; Allahverdyan et al AIP(05)cm/04 [exactly solvable]; Doplicher CMP(18)-a0908 [in local quantum theory]; Allahverdyan et al PRP(13) [understanding quantum measurement]; Burić et al PRA(13) [hybrid quantum-classical model]; Budiyono JSM(13)-a1310 [stochastic model]; La Cour FP(14)-a2104 [detector-based]; Johansen et al a1405/JPA [vs non-ideal classical measurements]; Herbut a1412 [theory of quantum premeasurement dynamics]; Brody & Hughston JPCS(15)-a1505 [universal quantum measurements]; Merlin IJMPB(15)-a1507 [types of particle detectors, and their Hamiltonians]; Weinberg PRA(16)-a1603 [density matrix evolution from Lindblad equation]; Eriksson et al a1708; Eriksson & Lindgren Entr(19)-a1901 [two-level system]; Auffèves & Grangier a1907-conf; Calzetta a1909; > s.a. Cluster Separability.
@ Noise and disturbance: Busch et al PLA(04), Buscemi et al PRL(14)-a1310; Rastegin QIC-a1406 [Rényi and Tsallis formulations].
@ Other topics: Landsman IJMPA(91) [and superselection sectors]; Mallah qp/02 [and conservation laws]; Lahti et al PLA(05)qp/04 [full observable from first and second moments]; Gudder RPMP(05) [additive and product structure]; Ji et al PRL(06) [distance measures]; Janssens qp/06 [inequalities]; Mermin QIP(06)qp, comment Ghirardi FP(08)-a0806, reply Mermin a0808 [and quantum computing]; Svozil NComp(11)-a1001-in [indefiniteness of quantum values]; Sych & Leuchs a1003-conf [quantum uniqueness]; Brasil et al FP(13)-a1109 [time duration]; Giovannetti et al PRL(12)-a1109 [bounds on parameter estimation]; Welper IJTP(13) [and quasiclassicality]; Kak a1404 [quantum measurement complexity]; Dall'Arno et al AIP(14)-a1502 [informational power]; Miyadera et al a1510 [relational vs absolute quantities]; > s.a. arrow of time; Beable; quantum information; quantum probabilities.

References > s.a. decoherence; foundations [including objectivity]; histories formulations; modified quantum mechanics; quantum entropy; wave-function collapse.
@ Non-technical: Dirac SA(63)may; Bell PW(90)aug; Gottfried PW(91)oct; Christian MR(96)qp/97; Clarke EJP(14) [in various interpretations of quantum mechanics]; Witas a1403 [heuristic explanation of the distinguished role of measurement]; Andreta de Castro et al a1908 [intro, historical].
@ Early papers: Furry PR(36), PR(36).
@ General: London & Bauer 39; Feyerabend ZP(57); Durand PhSc(60)apr; Daneri et al NP(62); Margenau AP(63); Shimony AJP(63)oct, comment Hack AJP(64)nov; Wigner AJP(63)jan, in(71); Rosenfeld PTPS(65); d'Espagnat ed-71; Prosperi in(71); Maxwell AJP(72)oct, AJP(73)aug; Margenau & Park FP(73); Reece IJTP(73); Peres PRD(80); Wheeler & Zurek ed-83; Walls et al PRD(85) [analysis]; Peres AJP(86)aug; Greenberger ed-87; Home & Whitaker PLA(88); Leggett FP(88); Maki PTP(88), PTP(89); Dicke FP(89); Peres PLA(90) [incompatible results]; Nakazato & Pascazio PLA(91); Busch et al 91; Schulman AP(91), 92; Braginsky et al 92; Mensky 93; Belavkin FP(94)qp/05 [without projection postulate]; Gurvitz QIP(03)qp/02 [classical apparatus]; Rajeev MPLA(03)qp-fs [errors]; Griffiths qp/06 [quantum mechanics without measurements]; Singh JPCS(09)-a0711 [quantum gravity favors wave-function-collapse interpretation]; Lundeen et al NatP(09)-a0807 [observables and detectors]; Amri a1001 [measurement apparatus]; Svensson Quanta(13)-a1202 [density-matrix formalism, pedagogical]; Eisert et al PRL(12) [undecidability of occurrence]; Vanni & Laura IJTP(13); Hájíček a1307; Griffiths PRA(17)-a1704 [what quantum measurements measure]; Neumaier a1912 [Born's rule and POVMs, intro]; Rizzi a2003 [II, ensemble interpretation].
@ The problem: Fine PRD(70), PRD(72), Brown FP(86) [insolubility]; Moldauer PRD(72); Bassi & Ghirardi PLA(00); Grübl PLA(03)qp/02 [impure states]; Wallace a0712-ch [rev]; Bub & Pitowsky in(09)-a0712 [as pseudo-problem]; Hobson a1206 [proposed resolution], criticism Kastner a1308; Boughn & Reginatto EPJH(13)-a1309 [pedestrian approach]; Bacciagaluppi IJTP(14) [insolubility from no-signalling]; Brukner a1407-proc; Nii et al a1603 [measurement outcomes and physical properties]; Baumann et al a1611 [incompatibility of collapse and unitarity]; Gisin a1701-ch [as a serious physics problem]; Mackintosh a1903; Boughn a2005 [the problem is artificial]; > s.a. Wigner's Friend.
@ And decoherence: Adler SHPMP(03); Dass qp/05-ln [intro]; Cornelio et al PRL(12)-a1203.
@ Measurement vs state preparation: Margenau PhSc(58)jan; Jauch HPA(64); Park & Band FP(92).
@ Measurement vs dynamics: Aharonov & Reznik qp/97; Nielsen PRL(97)qp.
@ Mathematical, algebraic approach: Maki PTP(90); Ozawa in(01)qp [axioms]; Sewell RPMP(05); Slavnov PPN(09)-a0810; Kishimoto a1304; Resende a2005.
@ Approaches: Albertson PR(6) [measurement operator]; Bohm & Hiley FP(84) [quantum potential]; d'Espagnat PLA(87) [and consistent histories]; Steane JPA(90); Hofer qp/00-conf; Marsh PRA(01) [system-apparatus density matrix]; Balduz qp/01 [theory of observers]; Loubenets JPA(01)qp [quantum stochastic approach]; Dumitru qp/02; Sokolovski & Sala Mayato PRA(05) [sum-over-histories view]; Sewell RPMP(05)mp; Allahverdyan et al qp/05 [as phase transition]; Belavkin qp/05-conf [dynamical solution]; Sewell AIP(07)-a0710 [solution within standard formalism]; Jaroszkiewicz PRS-a0812 [dynamical theory]; Gambini et al FP(10)-a0905, IJMPD(11)-a1009 [quantum gravity and undecidability]; Healey a1207 [pragmatist view]; de Ronde a1310 [in terms of causality]; Aerts & Sassoli de Bianchi AP(14)-a1404 [generalized Poincaré-Bloch sphere]; Nieuwenhuizen et al IJMPB(14)-a1406-ln [dynamical models]; Zwirn FP(16)-a1505 ["Convivial Solipsism"]; van Heugten & Wolters a1610 [on the Landsman-Reuvers proposal]; Brooks a1710 [quantum field theory]; Ydry a1811 [and black hole information loss]; Stoica a1903-conf [unitary evolution, and the block universe]; Foreman a1907 [weakly objective]; Hobson a1910; Hossenfelder & Palmer FrPh(20)-a1912 [Superdeterminism]; Gao Syn(19)-a2001 [the psychophysical connection].
@ And interpretations: McKnight PhSc(58)jul; Zeh FP(70); Elby FPL(93), Bene & Dieks qp/01 [modal]; Mittelstaedt 98; Genovese ASL-a1002; Jaeger a1707-in [overcoming conceptual imprecision]; Neumaier a1902 [in the thermal interpretation]; > s.a. pilot-wave interpretation.
@ More conceptual / philosophical: McKnight PhSc(57)oct; Bitbol PhSc(88)sep; Mohrhoff qp/01 [and weak objectivity]; French SHPMP(02) [history]; Bondoni a1006-wd [holistic point of view]; Echenique-Robba a1402 [quantum measurements as physical processes].

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