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arXiv · 1306.4202

COW test of the weak equivalence principle: A low-energy window to look into the noncommutative structure of space-time?

Anirban Saha
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Abstract

We construct the quantum mechanical model of the COW experiment assuming that the underlying space time has a granular structure, described by a canonical noncommutative algebra of coordinates $x^{\mu}$. The time-space sector of the algebra is shown to add a mass-dependent contribution to the gravitational acceleration felt by neutron deBrogli waves measured in a COW experiment. This makes time-space noncommutativity a potential candidate for an apparent violation of WEP even if the ratio of the inertial mass $m_{i}$ and gravitational mass $m_{g}$ is a universal constant. The latest experimental result based on COW principle is shown to place an upper-bound several orders of magnitude stronger than the existing one on the time-space noncommutative parameter. We argue that the evidence of NC structure of space-time may be found if the COW-type experiment can be repeated with several particle species.

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Anirban Saha. 2013-06-18. COW test of the weak equivalence principle: A low-energy window to look into the noncommutative structure of space-time?. https://doi.org/10.1103/physrevd.89.025010

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