Late-Time Background Expansion and Cosmographic Signatures of Finsler-Randers-Sasaki Cosmology
Abstract
In this work, we investigate the late-time expansion history and geometric diagnostics of logarithmic and exponential Finsler--Randers--Sasaki (FRS) cosmological models. We constrain both scenarios using cosmic chronometers, Baryon acoustic oscillations, and Pantheon+ Type~Ia supernovae, considering baseline fits as well as configurations calibrated with the local SH0ES distance-ladder prior. In the uncalibrated case, both profiles provide consistent descriptions of the late-time expansion history. Incorporating the SH0ES prior increases the inferred Hubble constant and modifies the inferred acoustic scale, reflecting the interplay between the local distance-ladder calibration and the BAO distance scale. Cosmographic reconstructions reveal a smooth transition from deceleration to acceleration at intermediate redshifts. Over the observationally relevant redshift range, both models exhibit a non-phantom, quintessence-like effective dark-energy sector. Finally, statefinder diagnostics distinguish the two FRS geometries: the logarithmic model remains relatively close to the canonical flat ΛCDM fixed point, whereas the exponential model follows a distinct dynamical trajectory. These results demonstrate that, despite their similar background expansion histories, the two FRS constructions can exhibit substantially different higher-order kinematic signatures.
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BibTeX
@misc{thunga2026latetime,
title = {{Late-Time Background Expansion and Cosmographic Signatures of Finsler-Randers-Sasaki Cosmology}},
author = {Thunga S and Devaraja Mallesha Naik and Manaswini B S and V Venkatesha},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.11269},
eprint = {2610.11269},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.11269},
}
RIS
TY - UNPB
TI - Late-Time Background Expansion and Cosmographic Signatures of Finsler-Randers-Sasaki Cosmology
AU - Thunga S
AU - Devaraja Mallesha Naik
AU - Manaswini B S
AU - V Venkatesha
PY - 2026
DA - 2026/10/08
PB - arXiv
DO - 10.48550/arxiv.2610.11269
UR - https://arxiv.org/abs/2610.11269
AB - In this work, we investigate the late-time expansion history and geometric diagnostics of logarithmic and exponential Finsler--Randers--Sasaki (FRS) cosmological models. We constrain both scenarios using cosmic chronometers, Baryon acoustic oscillations, and Pantheon+ Type~Ia supernovae, considering baseline fits as well as configurations calibrated with the local SH0ES distance-ladder prior. In the uncalibrated case, both profiles provide consistent descriptions of the late-time expansion history. Incorporating the SH0ES prior increases the inferred Hubble constant and modifies the inferred acoustic scale, reflecting the interplay between the local distance-ladder calibration and the BAO distance scale. Cosmographic reconstructions reveal a smooth transition from deceleration to acceleration at intermediate redshifts. Over the observationally relevant redshift range, both models exhibit a non-phantom, quintessence-like effective dark-energy sector. Finally, statefinder diagnostics distinguish the two FRS geometries: the logarithmic model remains relatively close to the canonical flat ΛCDM fixed point, whereas the exponential model follows a distinct dynamical trajectory. These results demonstrate that, despite their similar background expansion histories, the two FRS constructions can exhibit substantially different higher-order kinematic signatures.
ER -