Time |

**In General**

* __History of the concept__:
The oldest known concepts of time are cyclic; Only with the Zoroastrian Persians,
and Abraham's idea of a universal God (between 2100 and 1500 BC?) and later Judaism,
was there a deity intimately related to the fate of one's children, and the idea
of a future; This introduced in the Judaeo-Christian tradition and Western thought
the philosophical view of a linear, irreversible time; Aymara of the Andean highlands
view the past as in front of us (see can see it), and the future as behind us.

* __Re absolute time__:
In classical physics, with special relativity time and time translation invariance
have lost their independent identity from the rest of spacetime coordinate
transformations (Einstein: time is an illusion), but not so in common sense and
in quantum mechanics; It has been claimed that the contradiction can be solved
by the path-integral approach.

* __Possible positions__: Presentism, possibilism,
eternalism or block universe (and its variant evolving/growing block universe).

* __Block universe__: The view that considers
spacetime as a timelessly existing four-dimensional world, as opposed to an evolving
three-dimensional space.

* __Evolving block universe__: (Ellis) Spacetime
is a four-dimensional block and not an evolving space, but while the past is real and can
have had an effect on us today, the future does not yet exist; At the leading edge of
spacetime decoherence turns the uncertainty of the future into the certainty of the past.

@ __General__: Flood & Lockwood ed-86;
Griffin ed-86;
Costa de Beauregard 87;
Levich ed-95,
ed-96;
Rovelli NCB(95);
Svozil in(96)-a0904 [and intrinsic observers];
Parr 97;
Butterfield ed-99;
Foschini qp/99;
Tuisku et al PRS(09) [and thermodynamics, flow of energy];
Callender SA(10)jun;
Balasubramanian FP(13)-a1107 [what we don't understand];
Smolin 13;
Lachièze-Rey SHPMP-a1312 [no general concept of relativistic time];
Ashtekar SHPMP(15)-a1312 [in fundamental physics];
Kulikov InDeCS(15)-a1407 [nature of time];
Tavakol & Anderson a1506 [arguments against the non-existence of time];
Anderson a1906 [the problem of time];
Gisin nPhys(20)-a2002
[physics based on intuitionist mathematics, built on time-evolving processes];
Foti et al a2006 [there is only one time].

@ __Collections__: Feld ed-NYAS(67)#138 [*];
Baert ed-00;
Buccheri et al ed-03, ed-03.

@ __Books, I__: Gold ed-67;
Landsberg 82;
Fraser 87;
Coveney & Highfield 90;
Fraser ed-90;
Friedman 90;
Lockwood 05 [and time travel];
't Hooft & Vandoren 14 [scales];
Muller 16;
McCarthy & Seidelmann 18;
Rovelli 18.

@ __History__: Whitrow 89;
Szamosi HS(90) [Newtonian];
Borst 93 [Middle Ages];
Novikov 98;
Narayan a0708 [Indian cosmology, cycles].

@ __Philosophical / conceptual__: Whitrow 81;
Horwich 87;
Smith 93 [and language];
Smith & Oaklander 95 [metaphysics];
Caticha AIP(01)mp/00;
Weiskopf BJPS(04) [and cognition];
Oaklander 04 [ontology];
Lobo in(08)-a0710;
Callender 11;
Evans a1011;
Roemer a1202-conf [inner vs outer time];
Romero a1205-conf [nature of the present];
Smolin a1310 [temporal naturalism];
García Sucre a1404 [rev];
Radovan a1405,
a1509;
Butterfield EJAP-a1406 [re Dummett's writings about time];
Anderson a1409 [facets];
Huggett NYAS(14)-a1508 [physics of passage];
Simeonov PBMB(15)-a1505 [reflections];
Kulikov a1612 [and modern philosophy of physics];
Unnikrishnan a2001
[Bergson's philosophy of duration and simultaneity and Einstein's 1922 visit to Paris];
Rovelli a2105.

> __Related topics__:
see arrow of time; causality;
Evolution; time in physical theories.

> __Online resources__:
see International Society for the Study of Time;
FQXi essay contest.

**Different Views / Aspects**

* __Eternalism__: The view that all times are equally real.

@ __Being vs becoming__:
Savitt in(01);
Markosian in(02);
Davies SA(02)sep [flow];
Greene NYT(03);
Le Poidevin in(04) [perception];
Hartle AJP(05)feb-gq/04 [emergence of past, present and future];
Ellis GRG(06)gq,
a0812-essay [block universe vs evolution];
Miller qp/06-conf [quantum mechanics as a consistency condition];
Christian in(07)gq/06 [new generalized theory];
Maxwell in(07);
Peacock in(07);
Sorkin gq/07-ch [causal set sequential growth models as examples];
Romero FS-a1106 [Parmenidean conception of the universe];
Ellis & Goswami a1208-ch;
Gisin a1602-conf [time really passes].

@ __Presentism, possibilism and eternalism__: Petkov in(07) [argument for block universe view];
Besnard a1104;
Bacelar a1302-wd [and the relativity of simultaneity];
Romero FS-a1403
[presentism is in conflict with relativistic cosmology and advances in neurosciences];
Stoica a1903-conf [retrocausal block universe];
Rovelli FP(19)-a1910 [reality has a more complex temporal structure];
Le Bihan EJPS(20)-a2005 [and quantum gravity];
Slavov FP-a2009 [and the concept of 'now'];
> s.a. Presentism.

@ __Evolving block universe__: Ellis NYAS(14)-a1408 [and time at different scales];
Merali disc(15)jun [on Ellis' ideas];
Aerts a1511 [time and space
as creations rather than discoveries and underlying non-temporal, non-spatial reality];
Vaccaro a1804 [and human experience];
Correia & Rosenkranz 18.

@ __Relationalist view__: Barbour 99;
Barbour a0903-FQXi;
Rovelli FP(11)-a0903-FQXi;
Girelli et al a0903-FQXi [emergence model];
Anderson a1501
[Temporal Relationalism incorporating Principles of Dynamics];
Moreva et al JPCS(15)-a1502 [experiment with polarization entangled photons];
> s.a. parametrized theories.

@ __Emergence of time__: Briggs PRA(15)-a1503 [in classical and quantum mechanics];
Longo a1910 [in a non-commutative space];
Fujimoto a2001 [in algebraic quantum field theory];
Dias a2007 [from quantum events].

@ __The future__:
Harrington SHPMP(08) [point-present theories];
Torretti FP(11) [links between past and future];
Morita a2101 [the future cannot be open].

@ __Possibilities__: Tokuo IJTP(09) [time intervals as basic objects, and orthologic];
Boyarsky & Góra IJTP(09) [based on a particle's interaction with the Higgs field];
Musser SA(10)sep [the end of time?];
Anderson a1209;
Gryb & Mercati in(15)-a1301-FQXi [flow of time and the measurement process];
Dolce EPJW(13)-a1306 [elementary cycles of time];
Dowker NYAS(14)-a1405 [birth of spacetime atoms];
Sels & Wouters a1501 [time and thermodynamics];
Coumbe PRD(15)-a1502 [scaling of time and imaginary time at small scales].

@ __Related topics__: McKenzie a1603 [argument for the block universe?].

> __Related topics__: see
Advanced Time; clocks [measurement and timekeeping];
measurements in quantum theory; Simultaneity.

> __Online resources__: see Wikipedia page
on Eternalism.

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send feedback and suggestions to bombelli at olemiss.edu – modified 3 may 2021