Direct terrestrial test of Lorentz symmetry in electrodynamics to 10(-18).
Lorentz symmetry is a foundational property of modern physics, underlying the standard model of particles and general relativity. It is anticipated that these two theories are low-energy approximations of a single theory that is unified and consistent at the Planck scale. Many unifying proposals allow Lorentz symmetry to be broken, with observable effects appearing at Planck-suppressed levels; thus, precision tests of Lorentz invariance are needed to assess and guide theoretical efforts. Here we use ultrastable oscillator frequency sources to perform a modern Michelson-Morley experiment and make the most precise direct terrestrial test to date of Lorentz symmetry for the photon, constraining Lorentz violating orientation-dependent relative frequency changes Δν/ν to 9.2±10.7 × 10(-19) (95% confidence interval). This order of magnitude improvement over previous Michelson-Morley experiments allows us to set comprehensive simultaneous bounds on nine boost and rotation anisotropies of the speed of light, finding no significant violations of Lorentz symmetry.
Institut für Physik, Humboldt-Universität zu Berlin, Newtonstrasse 15, 12489 Berlin, Germany.
Moritz
M
Nagel
School of Physics, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia.
Stephen R
SR
Parker
Institut für Physik, Humboldt-Universität zu Berlin, Newtonstrasse 15, 12489 Berlin, Germany.
Evgeny V
EV
Kovalchuk
School of Physics, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia.
Paul L
PL
Stanwix
School of Physics, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia.|Institute for Photonics and Advanced Sensing, School of Physical Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia.
John G
JG
Hartnett
School of Physics, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia.
Eugene N
EN
Ivanov
Institut für Physik, Humboldt-Universität zu Berlin, Newtonstrasse 15, 12489 Berlin, Germany.
Achim
A
Peters
School of Physics, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia.
Michael E
ME
Tobar