Causality |

**In General** > s.a. causality in
quantum theory [including information causality and indefinite causal structures]; causality
violation; Determinism; locality.

* __Idea__: Explanations
are given in terms of efficient/physical cause, as opposed to final cause
(teleology); Often associated with predictability; The
dominant paradigm is the "machine", a deterministically predictive
one, despite setbacks from thermodynamics, special relativity, and quantum
mechanics (Prigogine); Should be modified, according to him, to allow for
self-organization and creation of order in non-linear
dissipative systems and non-equilibrium thermodynamics.

* __Rem__: Causality implies conservation of identity, a far from simple notion; It imposes strong demands on the universalizing power of theories concerned, often met by the introduction of a metalevel which encompasses the notions of 'system' and 'lawful behaviour'; In classical mechanics, the division between universal and particular leaves its traces in the separate treatment of kinematics and dynamics; > s.a. Dynamics [synthesis between kinematics and dynamics].

* __History__: Francis Bacon
considered causality as a mechanical relationship, as opposed to an abstract one.

@ __General references__: Fermi RMP(32);
Margenau PhSc(34)apr;
Bohm 57; Svechnikov 71; Jones AJP(96)mar [RL];
Hunter et al ed-98; Dowe & Noordhof 04; Hájíček phy/06 [and
liberty]; Ross & Spurrett BJPS(07)
[notions of cause and Russell]; Butterfield BJPS-a0708 [stochastic
Einstein locality]; Janzing a0708 [asymmetry
between cause and effect, Occam's razor, and thermodynamics]; Hájíček GRG(09)-a0803 [and
freedom of choice]; Pearl 09; Coecke & Lal a1010-wd [time asymmetry, quantum information processing]; Ellis a1212-FQXi [top-down causation]; Coecke et al a1711 [the time-reverse of any causal theory is eternal noise].

@ __Causation__: Ma FdP(00)qp/99-proc;
Dowe PhSc(04)dec
[conserved quantity theory]; Corry PhSc(06)jul
[revision avoiding Bertrand Russell's arguments]; Kistler 06.

@ __Other conceptual, philosophical__: Mehlberg IJTP(69)
[vs determinism]; Salmon PhSc(94)jun,
PhSc(97)sep;
Eckhardt SHPMP(06)
[and irreversibility]; Cat PhSc(06)jan
[fuzzy]; Smith BJPS(07)
[relationship between causal dependence and causal laws]; Frisch BJPS(09)
[role
of causality]; Norton BJPS(09),
reply
Frisch BJPS(09);
Verelst a1203 [analysis, application to theories of Newton and Leibniz]; Rédei & San Pedro SHPMP(12)-a1204 [inequivalent causality principles]; Vidunas a1707 [delegated causality in complex systems]; > s.a. Explanation; paradigms in physics.

> __Four causes__: see Efficient (Moving) Cause; Final Cause; Formal Cause; Material Cause; Marc Cohen's page.

> __Online resources__: see Wikipedia page.

**In Classical Theories** > s.a. causal
structures; causality conditions; dispersion [Kramers-Kronig relations]; geometry; spacetime
subsets.

* __Classical field theory__:
Expressed by the support of Green functions or the Kramers-Kronig dispersion
relations,
or *v*_{f}.

* __General relativity__:
For matter propagation, built in by the requirement that spacetime satisfy
a causality
condition.

@ __General references__: de Souza ht/97,
BJP(02)ht/00,
Bergqvist & Senovilla
CQG(99)gq [field
theory]; Patricot ht/04 [and
symmetries]; Triacca PLA(07)
[Granger causality for stochastic processes]; Yuffa & Scales EJP(12) [electrodynamics, and linear response]; Ajaib a1302 [physical vs numerical causality, and the Courant-Friedrichs-Lewy condition]; Baumeler & Wolf NJP(16)-a1507 [classical processes without causal order]; > s.a. field
theory.

@ __k-essence__:
Bruneton PRD(07)
[and MOND and other modified theories]; Babichev et al JHEP(08)-a0708.

@ __In relativity and gravity__: Jacobson in(91)
[general relativity]; Rohrlich AJP(02)apr
[and electromagnetism]; Bertolami & Lobo NQ-a0902;
Kochiras SHPSA(09) [Newton's causal and substance counting problems].

@ __And dispersion relations__: Wigner ed-64; Nussenzveig 71; Fearn & Gibb qp/03.

@ __Wave propagation__: Bonilla & Senovilla PRL(97)
[gravity in vacuum];
Mitchell & Chiao AJP(98)jan
[*v*_{g} < 0]; Smolyaninov JO(13)-a1210 [metamaterial model of causality]; > s.a. electromagnetism.

> __Related topics__: see gauge
choice [causality and gauge in electromagnetism]; gravitating
matter [and the speed of sound].

**Related Topics** > s.a. Retrocausation; tachyons; time; velocity.

* __Principle
of common cause__: The idea that simultaneous correlated events must have prior common causes, first made precise by Hans Reichenbach in 1956; It can be used to infer the existence of unobserved and unobservable events, and to infer causal relations from statistical relations; It does not appear to be universally valid, in particular its validity is questionable in quantum mechanics, nor is there agreement as to the circumstances in which it is valid; > s.a. Stanford Encyclopedia of Philosophy page.

* __ Emergent causality__: In one proposal, information is seen as a more fundamental concept than the laws of physics, which leads to a different understanding of spacetime where causality emerges from correlations between random variables representing physical quantities.

* __Other related concepts__: Arguments
by design (> see cosmology).

@ __Principle
of common cause__: Reichenbach 56; Henson SHPMP(05)qp/04, reply to comment SHPMP(13) [quantum mechanics]; Mazzola FP(12); Hofer-Szabó et al 13 [r CP(14)#3]; Cavalcanti & Lal JPA(14)-a1311 [modifications in light of Bell's theorem]; Mazzola & Evans a1703 [existence of Reichenbachian common cause systems].

@ __Emergent causality__: Baumeler & Wolf ISIT(14)-a1312, a1602 [intrinsic definition of randomness, and complexity].

@ __Causality vs correlations__: news pt(14)nov [information flow, and application].

@ __Probabilistic causality__: Price BJPS(91);
Twardy & Korb PhSc(04)jul; Dzhafarov & Kujala JMPsy-a1110; Zaopo a1209 [causal relations as observer-dependent]; Zhang BJPS(13) [connection between causality and probability].

@ __Other generalizations__: Choudhury & Mondal TMP(13) [almost causality, reflecting and distinguishing spacetimes]; Minguzzi a1709 [causality with non-round cones]; > s.a. causality conditions.

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17 nov 2017