Teleparallel Gravity Models Face Stringent Constraints from Cosmological and Wave Observations

Astrophysicists evaluating modifications to standard gravitational theory have placed precise constraints on teleparallel gravity models using observational datasets. In a study published in Astrophysics and Space Science, researchers examined the cosmological implications of modified teleparallel gravity formulated within the f(T) framework. The analysis evaluated the framework against current high-precision cosmological data to assess how well modified torsion-based models describe cosmic expansion relative to established cosmological baselines.

The investigation tested two distinct dark energy parametrizations within the teleparallel structure: the Chevallier-Polarski-Linder parametrization and the Barboza-Alcaniz parametrization. By integrating these mathematical descriptions of dark energy into the modified gravity equations, the authors established a systematic framework to probe how dark energy density and cosmic acceleration behave over time under non-standard gravitational dynamics.

To determine empirical bounds on the theoretical parameters, the team employed statistical analysis utilizing recent high-precision observational datasets. The empirical data incorporated baryon acoustic oscillation measurements from the Dark Energy Spectroscopic Instrument Data Release 2 alongside gravitational wave observations. These combined measurements enabled the researchers to constrain essential cosmological metrics, including the Hubble constant, model-specific parameters, and dark energy equation-of-state parameters.

Using the derived constraints, the authors evaluated key cosmological indicators governing the universe’s evolutionary history, focusing on the deceleration parameter, the effective equation of state, and the Om(z) diagnostic metric. These diagnostic tools allowed for a direct quantitative comparison between the dynamical behavior predicted by teleparallel models and the expectations set by the standard cosmological model.

The statistical fitting demonstrated that both modified gravity parametrizations successfully account for the observed late-time accelerated expansion of the universe. Furthermore, both models demonstrated a statistical fit to the observational data that is comparable to the standard flat Lambda Cold Dark Matter paradigm. However, the analysis indicated that the results do not present strong evidence favoring a definitive departure from standard cosmology.

Despite this statistical parity in fitting expansion data, the derived parameter values placed the general relativity limit beyond two standard deviations. This exclusion at more than the 2-sigma confidence level demonstrates that if teleparallel f(T) gravity operates as the underlying mechanism, its parameters exhibit a statistically significant shift away from standard general relativity bounds.

The dynamic properties of the two examined formulations revealed fundamental physical differences regarding stability. The model combining the Chevallier-Polarski-Linder parametrization with f(T) gravity exhibited phantom-crossing behavior and evolving dark energy dynamics, which resulted in a late-time violation of the null energy condition during cosmic progression.

Conversely, the configuration pairing the Barboza-Alcaniz parametrization with f(T) gravity remained strictly within the non-phantom regime throughout its evolution. By preserving all fundamental energy conditions, this formulation maintained greater theoretical stability while remaining fully compatible with current high-precision astronomical measurements as an alternative cosmological framework.

Subject of Research: Constraints on modified teleparallel gravity and dark energy parametrizations

Article Title: Constraints on teleparallel gravity with different dark energy parametrizations from DESI DR2 BAO and gravitational wave data

Article References: Mazumdar, R., Malakar, K., & Bhuyan, K. (2026). Constraints on teleparallel gravity with different dark energy parametrizations from DESI DR2 BAO and gravitational wave data. Astrophysics and Space Science, 371(11), Article 139. https://doi.org/10.1007/s10509-026-04671-4

Image Credits: AI Generated

DOI: 10.1007/s10509-026-04671-4

Keywords: teleparallel gravity, f(T) gravity, dark energy, cosmology, DESI DR2, baryon acoustic oscillations, gravitational waves, CPL parametrization, Barboza-Alcaniz parametrization, cosmic acceleration, Lambda-CDM, equation of state, deceleration parameter, null energy condition, phantom crossing, Om diagnostic, cosmological constraints, modified gravity