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arXiv · 2508.19912

Chaplygin and Polytropic gases Teleparallel Robertson-Walker $F(T)$ gravity solutions

Alexandre Landry
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Abstract

This paper investigates the Teleparallel Robertson-Walker (TRW) $F(T)$ gravity solutions for a Chaplygin gas, and then for any polytropic gas cosmological source. We use the TRW $F(T)$ gravity field equations (FEs) for each $k$-parameter value case and the relevant gas equation of state (EoS) to find the new teleparallel $F(T)$ solutions. For flat $k=0$ cosmological case, we find analytical solutions valid for any cosmological scale factor. For curved $k=\pm 1$ cosmological cases, we find new approximated teleparallel $F(T)$ solutions for slow, linear, fast and very fast universe expansion cases summarizing by a double power-law function. All the new solutions will be relevant for future cosmological applications on dark matter, dark energy (DE) quintessence, phantom energy, Anti-deSitter (AdS) spacetimes and several other cosmological processes.

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Alexandre Landry. 2025-08-27. Chaplygin and Polytropic gases Teleparallel Robertson-Walker $F(T)$ gravity solutions. https://doi.org/10.3390/math13193143

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