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arXiv · 2309.11536

Signature of Einstein-Cartan theory

Bruno Arderucio Costa·Yuri Bonder
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Abstract

We study the physical effects of torsion as predicted by the Einstein-Cartan theory in the test particle approximation and the non-relativist limit. We first present the corresponding non-relativistic Hamiltonian for a 2-spinor. Then, we solve an idealized reflection and transmission problem for a non-relativistic spin-$\frac{1}{2}$ beam travelling across a spin-polarized target. We identify deviations in the spin polarizations of the reflected and transmitted as observables capable of distinguishing Einstein-Cartan from standard general relativity. If measured, this effect would constitute compelling evidence for the presence of spacetime torsion.

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Bruno Arderucio Costa, Yuri Bonder. 2023-09-20. Signature of Einstein-Cartan theory. https://doi.org/10.1016/j.physletb.2023.138431

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