> s.a. constants and variation;
fermions; history of physics;
* History: 1892, H A Lorentz, proposal of the electron and use to explain properties of matter; 1897, J J Thomson, discovery of the electron as cathode rays; 1924, W Pauli, proposal of an inner degree of freedom, later associated by Kronig and by Goudsmit and Uhlenbeck with an inner rotational motion; 1927, C J Davisson & L H Germer, observation of electron diffraction by a crystal.
* Charge: Its absolute value is e = 1.60217733(49) × 10−19 C.
* Mass: me = 9.109 3826(16) × 10−31 kg ≈ 10−27 g or 511 keV/c2, with variation |μ·/μ0| < 3 × 10−14 yr−1, μ0 = mp / me.
* Electric dipole moment: Since 1950, experimenters have been trying to measure the electron's electric dipole moment pe and getting increasingly stringent upper limits, but no clear signal; Initially, the quest seemed dubious because a non-zero pe would break symmetries that were then thought to be inviolate; By the mid 1960s it was clear that those symmetries are in fact broken, but the standard model, which incorporates the known symmetry violations, predicts a value pe = 10−39 e · m, far too small to measure; However, beyond-the-standard-model theories predict much higher values, that should be measurable with molecular-beam techniques; 1996, Experimental bound pe ≤ 10−27 e · m; 2011, Experimental bound pe ≤ 1.05 × 10−28 e · m with 90% c.l.; 2012, Bounds from studies of electrons in solids are not yet as sensitive, but have been improving; 2013, pe ≤ 8.7 × 10−29 e · m with 90% c.l.; 2018, pe ≤ 1.1 × 10−29 e · m.
* Magnetic dipole moment: As of 2006, g/2 = 1.001 159 652 180 85 (76); As of 2008, 1.001 159 652 180 73 (28); For an electron bound to an atom g deviates from a value close to 2 by terms that depend on the ion's nuclear charge and the fine structure constant; The most successful prediction in phsyics.
@ General references: Majorana NC(37) [and positron]; Feynman PR(49) [positron]; issue PT(97)oct; Mac Gregor 92; Wilczek SA(12)jun [120th birthday]; Knuth a1511-in [current understanding]; Lincoln TPT(16)apr.
@ Internal structure: Robinson PLA(95); Hofer qp/96, PhyA(98)qp [and photons]; Pavšič et al HJ(95)qp/98.
@ Mass: Levshakov et al MNRAS(02)ap/01 [variation of mp/me]; Beier et al PRL(02); Cardone et al ht/05-ch; Jantzen & Ruffini GRG(12) [Fermi's analysis of the contribution of the electromagnetic field]; > s.a. energy [self-energy].
@ Magnetic dipole moment: Welton PR(48) [and electromagnetic field fluctuations]; Aspden IJTP(77) [heuristic model]; Vázquez IJTP(79) [corrections to g due to a Coulomb field]; Jáuregui & de la Peña PLB(81), Rivas phy/01 [and spin]; Awobode NCB(02); Steinmann CMP(03) [careful definition]; Brodsky et al NPB(04) [non-perturbative]; McCartor ht/04; Rosencwaig ht/06 [and self-energy, Casimir approach]; Awobode NCB(06); Aoyama et al PRL(07) [theory, 8th-order contribution]; Hanneke et al PRL(08); Giulini SHPMP(08) [spin]; Lush a0905 ["hidden momentum"]; Masood & Haseeb IJMPA(12)-a1204 [corrections at finite temperature]; de Rafael NPPS(12)-a1210 [update, standard model]; Mandache a1307 [physical origin]; Jung JHEP(13) [theoretical bound]; Davies cosmos(18)jul [the most successful prediction in phsyics]; Gabrielse et al a1904 [towards an improved measurement]; > s.a. Gyromagnetic Ratio; modified QED.
@ Electric dipole moment: Bernreuther & Suzuki RMP(91); Hudson et al Nat(11)may + news nat(11)may, bbc(11)may, pw(11)may, pt(11)jun; Eckel et al PRL(12) [in solids]; ACME Collaboration Sci(14)jan-a1310 + news SA(13)nov, pw(13)nov, news sn(18)oct, Nakai & Reece pt(18)nov [new experimental upper bounds].
Models and Related Topics > s.a. particle models [including description
as black holes]; particle nature and description; spinning particles.
* Positron: 2002, evidence that in a gas it can form bound states with molecules [@ Gilbert et al PRL(02)].
* Decay: The electron is the lightest known charged particle, so its decay (for example into a neutrino and a photon) would imply that charge is not always conserved; There are tight bounds on this process, and the electron lifetime is at least 6.6 × 1028 yr.
* Fractionalization: The phenomenon by which the electron splits into separate quasiparticles which carry its spin and its charge, and into real Majorana fermions which carry its Fermi statistics.
* Speculative: 2000, H Maris proposed that electrons can break up into smaller "electrinos" [@ news pn(00)sep].
@ Extended electron models: Dirac PRS(62) [charged conducting surface]; Yaghjian 06 [Lorentz-Abraham charged sphere model]; Likhtman ht/06 [string model]; Rahaman et al ASS(11)-a0904 [charged perfect fluid]; Hofer FP(11)-a1002 [geometric-algebra model]; Burinskii AIP(12)-a1104-GRF; Hofer JPCS(12) [and experiment]; Damour CRP-a1710 [Poincaré's 1905 model].
@ Geometrical models: Visser PLA(89) [electromagnetism + Newtonian gravity]; Pavšič et al PLB(93)qp/02 [Dirac equation from Clifford algebras]; Hofer qp/99-in; Ray & Bhadra IJMPD(04)gq/02 [Einstein-Cartan theory]; Giulini HSPMP(08)-a0710 [spin and special relativity]; Gsponer JMP(08) [pointlike, in Colombeau's theory]; Atiyah et al JHEP(15)-a1412 [5D Ricci-flat, evolving Taub-NUT geometry]; > s.a. gauge transformations [Maxwell theory].
@ Other models: Rosen IJTP(78) [theoretical approach to mass];
Fryberger PRD(81); Caldirola LNC(83); Burinskii JPCS(12)-a1109 [closed heterotic string]; Burinskii a1112-proc; Kazakov & Nikitin AP(12) [electron freely evolving in a photon bath, and effective infrared non-divergence].
@ Positron: Farmelo CP(10) [and Dirac]; Leone & Robotti EJP(10), AJP(12)jun [early history]; Cretu SHPMP-a1910 [history].
@ Fractionalization: Xu & Sachdev PRL(10) + news physorg(10)aug; news nat(12)apr.
@ Decay: Pradhan ht/03; Klapdor-Kleingrothaus et al PLB(06), Agostini et al PRL(15) [lower bounds on lifetime].
@ Angular momentum: Stewart CJP(09)qp/07; O'Connell JPA(16)-a1603 [interaction with the angular momentum of the electromagnetic field]; Białynicki-Birula & Białynicka-Birula PRL(17)-a1611 [relativistic wave packets carrying angular momentum]; Bliokh et al PRA(17)-a1706 [position, spin and orbital angular momentum operators]; Damski a1908 [spin angular momentum], a1908 [electromagnetic angular momentum].
@ Related topics: Matteucci AJP(90)dec [wave behavior]; Rivas JPA(03)phy/01 [dynamical equations]; Matteucci et al EJP(09) [wave behavior]; Cetto et al QS:MF(17)-a1707 [origin of electron spin and related wave function antisymmetry]; > s.a. locality; lorentz-symmetry violation; Stochastic Electrodynamics.
Applications and Experiments > s.a. bose-einstein condensates;
condensed-matter physics; Density Functional
Method; Luttinger Liquid.
@ Gas of free electrons: Verzegnassi et al a1706 [effect of a magnetic field, qft treatment].
@ Electrons in materials / lattices: Alloul 11 [in solids]; news pw(12)oct [nanocloaking devices for electrons inside materials]; Bach & Delle Site ch(14)-a1406 [open problems in many-electron theory]; Klopp & Veniaminov a1408 [interacting, in a random background]; news brown(14)oct [electron bubbles in ultracold liquid helium]; news upi(16)feb [electrons in graphene behaving as fluid]; Martin et al 16; Quinn a1706 [strongly correlated regime]; > s.a. Hofstadter's Butterfly.
@ Experiments and techniques: Richter Phy(12)feb [controlling electron spin and geometric phase]; Sancho a1601 [charge distribution, via Kapitza-Dirac diffraction]; Rashidi et al PRL(18) [mechanical control of single electrons].
@ Magnetic moment, measurements: Odom et al PRL(06) + pn(06)jul [best measurement]; Gabrielse pw(07)feb [implications]; Vogel CP(09) [and test of QED]; Sturm et al PRL(11) [in a bound state, stringent test to date of QED].
@ Magnetic moment, effects: Mera et al PRB(13)-a1206 [in a ferromagnet, interaction with conduction band electrons and with phonons].
> Related topics: see aharonov-bohm effect; diffraction; scattering; Wigner Crystal.
You know, it would be sufficient to really understand the electron – Albert Einstein
– journals – comments
– other sites – acknowledgements
send feedback and suggestions to bombelli at olemiss.edu – modified 15 oct 2019