Abstract In our paper, ‘Matter waves and clocks do not observe uniform gravitational fields’ (Asenbaum et al 2024 Phys. Scr. 99 046103), we analyze how measurements with matter waves and clocks depend on non-gravitational forces and on a UGF. The comment on our paper rests primarily on a misreading of the paper’s central physical setup. We do not consider the simplification that the redshift apparatus is fixed. Rather, our description remains general and keeps the non-gravitational forces independent of the UGF, which covers all configurations: the redshift setup being fixed, in free fall, or arbitrary upward or downward acceleration. This allows us to establish that the redshift measurement follows the non-gravitational forces rather than the UGF.Abstract In our paper, ‘Matter waves and clocks do not observe uniform gravitational fields’ (Asenbaum et al 2024 Phys. Scr. 99 046103), we analyze how measurements with matter waves and clocks depend on non-gravitational forces and on a UGF. The comment on our paper rests primarily on a misreading of the paper’s central physical setup. We do not consider the simplification that the redshift apparatus is fixed. Rather, our description remains general and keeps the non-gravitational forces independent of the UGF, which covers all configurations: the redshift setup being fixed, in free fall, or arbitrary upward or downward acceleration. This allows us to establish that the redshift measurement follows the non-gravitational forces rather than the UGF.

Physica ScriptaOct 22, 20260 citations

Matter and light wave interferometry in gravitational fields

Leo Stodolsky

General Relativity and GravitationDec 1, 1979181 citations

Velocimetry of cold atoms by matter-wave interferometry

Max Carey, Jack Saywell, David Elcock +2 more

We present an elegant application of matter-wave interferometry to the velocimetry of cold atoms whereby, in analogy to Fourier transform spectroscopy, the one-dimensional velocity distribution is manifest in the frequency domain of the interferometer output. By using stimulated Raman transitions between hyperfine ground states to perform a three-pulse interferometer sequence, we have measured the velocity distributions of clouds of freely expanding $^{85}\mathrm{Rb}$ atoms with temperatures of 34 and $18\phantom{\rule{4pt}{0ex}}\ensuremath{\mu}\mathrm{K}$. Quadrature measurement of the interferometer output as a function of the temporal asymmetry yields velocity distributions with excellent fidelity. Our technique, which is particularly suited to ultracold samples, compares favorably with conventional Doppler and time-of-flight techniques, and it reveals artefacts in standard Raman Doppler methods. The technique is related to, and provides a conceptual foundation of, interferometric matter-wave accelerometry, gravimetry, and rotation sensing.We present an elegant application of matter-wave interferometry to the velocimetry of cold atoms whereby, in analogy to Fourier transform spectroscopy, the one-dimensional velocity distribution is manifest in the frequency domain of the interferometer output. By using stimulated Raman transitions between hyperfine ground states to perform a three-pulse interferometer sequence, we have measured the velocity distributions of clouds of freely expanding $^{85}\mathrm{Rb}$ atoms with temperatures of 34 and $18\phantom{\rule{4pt}{0ex}}\ensuremath{\mu}\mathrm{K}$. Quadrature measurement of the interferometer output as a function of the temporal asymmetry yields velocity distributions with excellent fidelity. Our technique, which is particularly suited to ultracold samples, compares favorably with conventional Doppler and time-of-flight techniques, and it reveals artefacts in standard Raman Doppler methods. The technique is related to, and provides a conceptual foundation of, interferometric matter-wave accelerometry, gravimetry, and rotation sensing.

arXiv:1802.02190Physical Review AFeb 28, 20199 citations

^{85}\mathrm{Rb}

atoms with temperatures of 34 and $18\phantom{\rule{4pt}{0ex}}\ensuremath{\mu}\mathrm{K}$. Quadrature measurement of the interferometer output as a function of the temporal asymmetry yields velocity distributions with excellent fidelity. Our technique, which is particularly suited to ultracold samples, compares favorably with conventional Doppler and time-of-flight techniques, and it reveals artefacts in standard Raman Doppler methods. The technique is related to, and provides a conceptual foundation of, interferometric matter-wave accelerometry, gravimetry, and rotation sensing.