Tests
of the Equivalence Principle| Tests
of the Equivalence Principle |
In General > s.a. [Detector];
eötvös experiment.
* History: Earliest recorded
test was by Galileo; The best experimental test is to compare the free-fall
acceleration of different materials; Late
1800's,
validated to one part in 108 by the Eötvös
experiment; Eöt-Wash
experiments on the weak principle, the best tests as of 2001, confirm it up
to corrections of order 10–13; 2004,
The most accurate experiment with atoms shows no departure [@ news pw(04)nov].
* Of strong equivalence principle:
2003, the only technique available to test it is Lunar Laser Ranging (> see tests
of general relativity); 2004,
results give 
(mg/mi)SEP =
(–2.0 
2.0) ×
10–13, and 
:=
4
–
–3
= (4.4 4.5) ×
10–4.
* Results
from Nordtvedt effect: Experiments give mg/mi
= 1 + (UG / mc2),
with < 10–12 so
far.
* Results with self-energy:
Satisfied up to 10–3 [@
Baeßler
et al PRL(99),
news PT(99)nov].
* Plans: 2004, NASA-ESA
STEP (Satellite Test of the Equivalence Principle) to be put in orbit in 2005,
aims at 10–18 accuracy;
SEE (Satellite Energy
Exchange); GReAT experiment, involving a free fall by 4 km in the stratosphere,
will test the wep to 1 part in 5 
1015 at
95% cl, 100 times better than ground-based; 2005,
MICROSCOPE (MICRO-Satellite à trainée
Compensée pour l'Observation du Principle d'Équivalence) scheduled
for 2008, will measure differential acceleration of test masses in a rotating
spacecraft.
References > s.a. fine
structure constant; neutrino oscillations; Nordtvedt
Effect; tests of general relativity with
light.
@ Status, reviews: Damour CQG(96)gq, gq/97-in; news
pw(05)jan; news NASA(07)may.
@ General: Gabriel & Haugan PRD(90);
Klein & Mittelstaedt
AJP(97) [demo];
CPLEAR collaboration PLB(99)
[K0's];
Haugan & Lämmerzahl
LNP(01)gq;
Luo et al PRD(02)gq/01 [rotation];
Gundlach NJP(05)
[lab tests]; Silenko & Teryaev PRD(07)gq/06 [spin-gravity
coupling]; Newburgh EJP(08) [simple demonstration].
@ Neutrino oscillations: Halprin et al PRD(96); Fogli et al PRD(99)hp;
Datta PLB(01).
@ Earth satellites: CQG(01)#13
issue; Moffat & Gillies NJP(02)gq [wep];
Iorio GRG(04)gq/03 [wep];
Sumner GRG(04)
[STEP]; Nobili et al GRG(08) [LAGEOS and LAGEOS II, limitations].
@ Solar system: Anderson et al ap/95-in,
ApJ(96)ap/95 [Earth-Mars
ranging]; Overduin PRD(00)gq [and
higher-dimensional gravity].
@ Binary pulsars: Wex gq/95/A&A
[proposal]; Arzoumanian ap/02-in.
@ Cosmology:
Amendola & Quercellini
PRL(04)ap [large-scale
structure]; Boucher et al PRD(04)ap [cmb
constraints]; Kesden & Kamionkowski PRD(06)ap
[galaxy tidal tails and dark matter]; > s.a. cmb.
@ Other proposals: Álvarez & Mann PRD(97)gq/96 [lepton
and meson sectors]; Peters
et al Nat(99)aug
[cooled Cs atoms]; Guzzo et al APP(02)
[supernova 
's]; Nobili
et al
PLA(03)
[GG proposal]; Wesson IJMPD(05)gq/06 [and
higher-dimensional gravity]; Dimopoulos et al PRL(07)gq/06 [atom
interferometry]; Kirch phy/07 [muonium];
Schlamminger et al PRL(08)
[rotating torsion balance].
> Related topics: see radiation [accelerated
charge]; self-force [radiation reaction].
Main page – Abbreviations – Journals – Comments – Other
sites – Acknowledgements
Send feedback and suggestions to bombelli at olemiss.edu – Modified
23 jun 2008