Quantum gyroscopes and Gödel's universe: entanglement opens a new testing ground for cosmology

New Frontiers at the Interface of General Relativity and Quantum Optics

“…This rotation gives rise to the Sagnac effect of Gödel's Universe, see Delgado et al (2002) and Kajari et al (2004). We conclude by emphasizing that the metric (7) is by no means a realistic model of our universe, since it cannot explain the red-shift observed for the distant stars.…”

Proof-of-concept experiments for quantum physics in space

“…Since rotating masses are involved, the experimental scheme is naturally equivalent to the one used for the test of the Lense-Thirring effect (see above). Taking into account the overall mass density distribution (Delgado et al assume ρ = 2 · 10 −31 g cm −3 ) one can predict the rotation-rate for the universe to be Ω U ∼ = 4 × 10 −19 rad s −1 , which is still small compared to the rotation rate corresponding to, for example, the Earth's Lense-Thirring effect Ω T L ∼ = 10 −14 rad s −1 [34]. Currently, without using entanglement, the best achievable accuracy is approx.…”

On the gravitomagnetic time delay

“…The relative time delay for a signal from the observer (R 1 = 0) to a local distance R compared to R/c is thus given by (Ω × R) 2 /c 2 , which is negligibly small on the basis of the current upper limit of Ω ≤ 10 −24 sec −1 on the possible rate of rotation of the universe [2], [24]- [27].…”