English

Non-Affine Extensions of the Raychaudhuri Equation in the K-essence Framework

General Relativity and Quantum Cosmology 2025-06-06 v2 High Energy Physics - Theory

Abstract

We present a new avenue of the Raychaudhuri Equation (RE) by introducing a non-affine parametrization within the k-essence framework. This modification accounts for non-geodesic flow curves, leading to emergent repulsive effects in cosmic evolution. Using a DBI-type k-essence Lagrangian, we derive a modified RE and demonstrate its ability to address the Hubble tension while predicting a natural emergence of a dynamical dark energy equation of state. Our Bayesian analysis, constrained by cosmological data, supports the theoretical scaling relation of the k-essence field (ϕ˙\dot{\phi}) and the cosmic scale factor (aa). Furthermore, we reinterpret the modified RE as an anti-damped harmonic oscillator, we found a caustic avoidance signature, it may reveal classical or quantum-like effects in cosmic expansion. These results suggest a deep connection between scalar field dynamics and modified gravity, offering new perspectives on the nature of the expansion history of the universe.

Keywords

Cite

@article{arxiv.2503.03076,
  title  = {Non-Affine Extensions of the Raychaudhuri Equation in the K-essence Framework},
  author = {Samit Ganguly and Goutam Manna and Debashis Gangopadhyay and Eduardo Guendelman and Abhijit Bhattacharyya},
  journal= {arXiv preprint arXiv:2503.03076},
  year   = {2025}
}

Comments

15 pages, 6 figures, 4 tables, Accepted from Physics Letters B