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arXiv · 2608.17058

Wormhole Reconstruction in Non-Conservative Unimodular Gravity: Ricci Scalar as an Independently Prescribed Curvature Profile

Marcelo H. Alvarenga·Rodrigo Santos Bufalo·Júlio C. Fabris
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Abstract

The absence of an algebraic relation between the Ricci scalar and the trace of the energy-momentum tensor in Non-Conservative Unimodular Gravity ($\mathrm{NUG}$) opens new possibilities for constructing spacetime geometries from prescribed curvature profiles. Exploiting this property, we develop a curvature reconstruction framework in which traversable wormhole geometries are generated directly from a prescribed curvature profile rather than from the matter sector or the metric functions. The reconstruction procedure is implemented for a power-law Ricci scalar combined with three different redshift functions, leading to distinct classes of static and spherically symmetric wormhole solutions. We investigate their geometrical properties, asymptotic behavior and null energy condition. Although the radial null energy condition remains necessarily violated at the throat, we show that the dimensionless curvature parameter controls the intensity of the exotic matter supporting the wormhole, while the curvature exponent determines the global asymptotic structure of the reconstructed spacetime. In particular, the critical configuration separating asymptotically flat solutions from geometries with residual asymptotic deformation naturally emerges from the reconstruction scheme. These results establish curvature reconstruction from prescribed Ricci scalar profiles as a viable geometrical framework for generating compact-object spacetimes within non-conservative unimodular gravity.

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Marcelo H. Alvarenga, Rodrigo Santos Bufalo, Júlio C. Fabris. 2026-08-17. Wormhole Reconstruction in Non-Conservative Unimodular Gravity: Ricci Scalar as an Independently Prescribed Curvature Profile. https://arxiv.org/abs/2608.17058

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