Probing Planck-scale spacetime by cavity opto-atomic $^{87}$Rb interferometry

Abstract

The project of "quantum spacetime phenomenology" focuses on searching pragmatically for the Planck scale quantum features of spacetime. Among these features is the existence of a characteristic length scale addressed commonly by effective approaches to quantum gravity (QG). This characteristic length scale could be realized, for instance and simply, by generalizing the standard Heisenberg uncertainty principle (HUP) to a "generalized uncertainty principle" (GUP). While usually it is expected that phenomena belonging to the realm of QG are essentially probable solely at the so-called Planck energy, here we show how a GUP proposal containing the most general modification of coordinate representation of the momentum operator could be probed by a "cold atomic ensemble recoil experiment" (CARE) as a low energy quantum system. This proposed atomic interferometer setup has advantages over the conventional architectures owing to the enclosure in a high finesse optical cavity which is supported by a new class of low power consumption integrated devices known as "micro-electro-opto-mechanical systems" (MEOMS). In the framework of a top-down inspired bottom-up QG phenomenological viewpoint and by taking into account the measurement accuracy realized for the fine structure constant (FSC) from the Rubidium ( 87 Rb) CARE, we set some constraints as upper bounds on the characteristic parameters of the underlying GUP. In the case of superposition of the possible GUP modification terms, we managed to set a tight constraint as 0.999978 < λ0 < 1.00002 for the dimensionless characteristic parameter. Our study shows that the best playground to test QG approaches is not merely the high energy physics, but a table-top nanosystem assembly, as well.

Generalized uncertainty principle and white dwarfs redux: How the cosmological constant protects the Chandrasekhar limit

“…From phenomenological point of view, the GUP parameter can be treated as a free parameter a priori, which can be constrained from experiments [9][10][11][12]; α as large as 10 34 is consistent with the Standard Model of particle physics up to 100 GeV [9], while a tunneling current measurement gives α 10 21 [13]. See also [14][15][16].It turns out that GUP has a rather drastic effect on white dwarfs. This is somewhat of a surprise, since we do not usually expect GUP correction to be important for scale much above the Planck scale.…”

Squeezed coherent states for gravitational well in noncommutative space

“…Instead of building a larger collider, the energy limitation problem can be overcome with the help of performing passive experiments using interferometry. Numerous proposals are there in this regime [19,20,21,22,23,24,25,26,27,28]. However, to the best of knowledge of present authors, none of them had yet been carried out.…”

A Possible Solution of the Cosmological Constant Problem based on Minimal Length Uncertainty and GW170817 and PLANCK Observations

“…Several approaches to the quantum gravity, such as GUP, predict a minimal length uncertainties that could be related to the Planck scale [20,21]. There were various laboratory experiments conducted to examine the GUP effects [47][48][49][50]. In this section, we focus the discussion on GUP with a quadratic momentum uncertainty [20,21].…”