In General > s.a. electromagnetism / causality [light cone]; physical constants [speed].
* History: Early ideas – Emission theory (light from our eyes shines upon the objects we see), believed by Plato, Euclid and Ptolemy, and experimentally proved wrong by al-Hassan Ibn al-Haytham; 1637 – Descartes, particles; 1678 – Huygens, waves, that slow down in refraction; 1704 – Newton, particles that speed up in refraction (it was assumed that light waves would be longitudinal, and did not explain polarization); 1801 – Young, waves, from interference (and introduced idea of transverse waves); 1850 – Foucault, waves, from slowdown in refraction; 1905 – Planck/Einstein, photons; {# Grimaldi, Herschel}.
@ General references, I: in Lightman 86, p137 ff; Sobel 87; Perkowitz ThSc(93)mar [beyond the blue]; Lynch & Livingston 95; Silverman 98; García-Matos & Torner 15; Wiseman a1510-PS [fundamental features that distinguish laser light from thermal light].
@ General references, II/III: Breslin & Montwill 13; Pathak & Ghatak a1705 [rev, classical and non-classical, and applications].
@ History: Zajonc 93; Perkowitz 96 [and art]; Park 97; Shea AJP(98)jul [Rømer's experiment]; Potter a0811 [Lorenz's model]; Al-Khalili bbc(09)jan [al-Hassan Ibn al-Haytham]; Sparavigna IJS-a1302 [reflection and refraction in Robert Grosseteste's treatise]; Bermudez et al FMO(16)-a1506-proc; news APS(16)jul [Fresnel's work]; Yajnik BIPA-a1905 [Sudarshan's diagonal representation]; > s.a. history of physics [electromagnetism].
@ Nature: Newton PTRS(1672), reprinted AJP(93)feb [colors]; Young PTRS(1802) [wave theory]; > s.a. spin models.

Classical Effects and Properties > s.a. aharonov-bohm effect; diffraction; interference; optics; phase; polarization; radiation.
* Talbot effect: The repeated self-imaging of a diffraction grating, reported in 1836 by Henry Fox Talbot, rediscovered by Lord Rayleigh in 1881; Explained by near-field interference [@ news pw(01)jun].
@ Orbital angular momentum: Allen et al PRA(92); Leach et al PRL(02); Padgett et al PT(04)may; Tiwari qp/06; Vitullo et al PRL(17)-a1607; > s.a. doppler effect.
@ Related topics: NS(90)sep1, 40-44 [rainbows]; Harris CP(95) [interference and fluctuations, speckle]; Sanz & Miret-Artés JChemP(07)qp [Talbot effect in quantum mechanics, in terms of Bohmian mechanics]; Götte et al PRS(07) [dragging by a rotating medium].
> Related topics: see Caustics; Coherence; energy-momentum tensor; Rabi Model [coupling to matter]; Rainbow; thermodynamic systems [thermal light].

Anomalous Propagation > s.a. dispersion; photon; wave phenomena.
* Scharnhorst effect: Superluminal propagation in matter obtained by suppressing vacuum modes (> see casimir effect).
* Slowdown: 1997, 17 m/s in BEC; 2000, 1 mph in BEC; 2001, Light effectively slowed down to vg = 0, its information stored in collective spin states of a dilute Rb gas, with the possibility of reading it out later; However, most light packets lose their shape when their speed is decreased, which limits their applicability in telecommunications; 2004, optical solitons made to move at 10−6 c.
* Standstill: 2002, Achieved in crystals, can be useful for high-density information storage for quantum computing.
@ Superluminal: Valentini PLA(89); news Nat(90)mar; Scharnhorst PLB(90); Barton PLB(90); Wang et al Nat(00)jul; Jackson et al PRA(01)phy/00; Shore gq/03-proc, NPB(07)ht [from quantum field theory effects]; Chen et al PRA(08)-a0807 [control]; Cialdi et al NJP(09)-a0904 [single photon]; news(11)jul, sci(11)aug; Weinstein a1203 [discussion between Einstein and Wien]; > s.a. Superluminal Propagation.
@ Slowdown: Vestergaard Hau et al Nat(99)feb [17 m/s in BEC]; Fiurasek et al PRA(02)qp/00; Phillips et al PRL(01) + pn(01)jan; news pn(07)may.
@ Standstill, storage: Vestergaard Hau SA(01)jul; Bajcsy et al Nat(03)qp [pulses in Rb]; Tanji et al PRL(09) + Laurat Phy(09)jul [and quantum information networks]; Havey CP(09) [in ultracold and high-density atomic gases]; de Riedmatten Phy(13), Heinze et al PRL(13) + news ns(13)jul [long-term storage]; Wiersma Phy(15)jun [trapping in Lieb lattices]; > s.a. photon.
@ Accelerating beams: news pw(12)nov [light following curved trajectories in free space]; Bekenstein et al PRX(14) [accelerating wave packets in curved space].

Other Propagation Effects > s.a. black-hole analogs [optical]; gravitational phenomenology; photon phenomenology; Reflection; refraction.
* Speed: Notice that the invariance of the speed of light only applies to plane waves; Spatial structure in a beam can reduce the speed even in vacuum.
@ Various materials: Neutze & Stedman PRA(98) [accelerating media]; Ward CP(99) [photonic materials]; Novello & Salim PRD(01) [non-linear dielectric, effective metric]; Michinel et al PRE(02) + pn(02)jul ["light droplets"]; Ramakrishna & Armour AJP(03)jun-cm/02 [absorbing media]; Li & Sun CTP(06)qp/05 [3+1-level atoms]; Garanovich et al PRP(12) [in modulated photonic lattices]; Popoff et al PRL(14) [control of light transmission through disordered media].
@ Inhomogeneous: Piwnicki IJMPA(02) [geometrical].
@ Scattering: Lagendijk & van Tiggelen PRP(96) [multiple]; Berman CP(08) [by atoms and vapors]; Bini et al EPL(13)-a1408 [by radiation fields]; Liu Phy(19) [superscattering, with metamaterial].
@ Interaction with matter: Baragiola PhD-a1408; López Carreño & Laussy PRA(16)-a1601 [quantum light and harmonic oscillators].
@ In curved spacetime: Batic et al PRD(15)-a1412 [deflection angle, lensing, bound states]; Mannheim a2105 [light rays do not always follow null geodesics]; > s.a. electromagnetism in curved spacetimes; lensing; matter and radiation near black holes; perturbed FLRW.
@ Gravitational interactions: Faraoni & Dumse GRG(99)gq/98; Kopeikin & Korobkov in(14)gq/05 [propagation in the field of radiative gravitational multipoles]; Vilasi et al CQG(11)-a1009 [with gravity as a wave and as a particle]; Rätzel et al NJP(16)-a1511 [gravitational field of a laser pulse].
@ In cosmology: Ellis et al CQG(98) [lensing and caustic effects]; Mustapha et al CQG(98) [distance-redshift]; More et al ApJ(09)-a0810 [transparency]; Räsänen JCAP(09)-a0812, JCAP(10)-a0912 [clumping and distance-redshift]; Maziashvili PRD(12)-a1206 [stochastic background, and light incoherence rate]; Fleury a1511-PhD [inhomogeneous and anisotropic cosmologies]; > s.a. averaging in cosmology.
@ Related topics: Punzi et al CQG(09)-a0711 [in area-metric background]; Giovannini et al Sci(15)feb-a1411 [speed v < c in free space].
> Gravity-related topics: see doubly special relativity; observational cosmology [birefringence]; tests of general relativity with light.

Quantum Aspects > s.a. photons; QED.
* History: The theoretical basis for the full quantum characterization of light was introduced by Glauber in 1963.
* Description: As shown by Białynicki-Birula, optics also admits a hydrodynamical formulation in terms of photon trajectories when the existence of a wave function for photons is assumed, analogous to the pilot-wave description of the behavior of massive particles.
@ General references: Glauber PR(63); Brańczyk et al JOSA(17)-a1605 [thermal light as a mixture of sets of pulses]; Kedia et al a1706 [knotted states]; Bradler et al a1810 [quantum states and graph isomorphism]; Tsang CP(19)-a1906 [tackling the diffraction limit and photon shot noise].
@ Coupling to matter: Sørensen & Sørensen PRA(08)-a0711, Hammerer et al RMP(10)-a0807 [ensemble of identical atoms]; Picón et al NJP(10)-a1005 [and atoms, angular momentum exchange]; De Liberato PRL(14)-a1308 [strong-coupling regime with matter]; Lachman et al SRep-a1605 [from many independent emitters]; Salasnich 17 [and matter]; Obšil et al a1705 [from a large number of trapped ions]; Zubizarreta et al LPR(20)-a1901 [photon statistics]; Karnieli et al a2011 [light emission and quantum electrodynamics].
@ Non-classical nature: Steudle et al PRA(12)-a1107 [experiment]; Dodel et al Quant(17)-a1611 [witnessing with the human eye].
@ Degree of non-classicality: Mraz et al PRA(14); Kühn & Vogel PRA(14); Lee et al PRA(16)-a1606; > s.a. Coherence.
> Specific aspects: see localization; photon phenomenology [including entanglement]; quantum-gravity effects; radiation.
> Related topics: see Chemical Potential; Hanbury Brown-Twiss Effect; quantum chaos; Solid Light; Superfluids; Wave-Particle Duality.

Applications > s.a. earth [atmospheric optics]; optical technology [including lasers]; Spectroscopy.
@ Colors: Weinberg GRG(76); Pease AJP(80)nov [RL]; Rossotti 88; Perkowitz ThSc(91)may; Gage 93, 99; Nassau 01; Kentsis phy/05 [Goethe's theory]; Sparavigna IJS(14)-a1212 [Robert Grosseteste on the nature of colors]; Mota & Lopes dos Santos PhysEd(14) [additive and subtractive mixtures]; Woolfson 16 [popularization].
@ Art: Rossing & Chiaverina 99 [II, introductory physics for visual arts]; Taft & Mayer 00 [painting].
@ Other practical aspects: Woolfson 11 [imaging].
> Online resources: see website.

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