# Resolving the gravitational redshift across a millimetre-scale atomic sample.

@article{Bothwell2022ResolvingTG, title={Resolving the gravitational redshift across a millimetre-scale atomic sample.}, author={Tobias Bothwell and Colin J. Kennedy and Alexander Aeppli and Dhruv Kedar and John M. Robinson and Eric Oelker and Alexander Staron and Jun Ye}, journal={Nature}, year={2022}, volume={602 7897}, pages={ 420-424 } }

Einstein's theory of general relativity states that clocks at different gravitational potentials tick at different rates relative to lab coordinates-an effect known as the gravitational redshift1. As fundamental probes of space and time, atomic clocks have long served to test this prediction at distance scales from 30 centimetres to thousands of kilometres2-4. Ultimately, clocks will enable the study of the union of general relativity and quantum mechanics once they become sensitive to the…

## 25 Citations

A lab-based test of the gravitational redshift with a miniature clock network

- Physics
- 2022

Einstein’s theory of general relativity predicts that when two clocks are compared using light, a clock at a higher gravitational potential will tick faster than an otherwise identical clock at a…

UGR tests with atomic clocks and atom interferometers

- Physics
- 2022

Atomic interference experiments test the universality of the coupling between matter-energy and gravity at diﬀerent spacetime points, thus being in principle able to probe possible violations of the…

Quantumness of gravity in harmonically trapped particles

- Physics
- 2022

This study investigates the quantumness of gravity under the setup of the atomic interferometry. We evaluated interference visibility considering a particle with internal energy levels in a harmonic…

Differential clock comparisons with a multiplexed optical lattice clock.

- PhysicsNature
- 2022

Rapid progress in optical atomic clock performance has advanced the frontiers of timekeeping, metrology and quantum science1-3. Despite considerable efforts, the instabilities of most optical clocks…

Light propagation and atom interferometry in gravity and dilaton fields

- PhysicsPhysical Review D
- 2022

Dark matter or violations of the Einstein equivalence principle inﬂuence the motion of atoms, their internal states as well as electromagnetic ﬁelds, thus causing a signature in the signal of atomic…

Spurious Radial Migration from Relativistic Effects in the Milky Way Disk

- PhysicsResearch Notes of the AAS
- 2022

The gradient of the gravitational redshift in the potential of the Milky Way induces an apparent spurious radial migration. I show that this effect is simply related to the local acceleration, which…

Hamiltonian engineering of spin-orbit coupled fermions in a Wannier-Stark optical lattice clock

- Physics
- 2022

Engineering a Hamiltonian system with tunable interactions provides opportunities to optimize performance for quantum sensing and explore emerging phenomena of many-body systems. An optical lattice…

Determining the atom number from detection noise in a one-dimensional optical
lattice clock

- PhysicsApplied Physics Letters
- 2022

In this paper, we demonstrate in situ synchronous frequency comparison between distinct regions in a one-dimensional optical lattice. The synchronous comparison instability is well below the Dick…

Pauli blocking of stimulated emission in a degenerate Fermi gas

- Physics
- 2022

The Pauli exclusion principle in quantum mechanics has a profound inﬂuence on the structure of matter and on interactions between fermions. Almost 30 years ago it was predicted that the Pauli…

Spin-squeezing swapping for differential measurements with atom interferometers and clocks

- Physics
- 2022

Thanks to common-mode noise rejection, di ﬀ erential conﬁgurations are crucial for realistic applications of phase and frequency estimation with atom interferometers. Di ﬀ erential interferometry can…

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