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arXiv · 2004.02934

Response to Comment on "Reexamining $f(R,T)$ Gravity''

Sarah B. Fisher·Eric D. Carlson
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Abstract

Harko and Moraes claim that in $f(R,T)$ gravity with $f(R,T)=f_1(R)+f_2(T)$, the term $f_2(T)$ cannot be incorporated in the matter Lagrangian ${\cal L}_m$. A careful examination of their Comment finds that they have made several dubious assumptions without indicating any errors in our work. Most notably, they have unjustifiably claimed that the two terms ${\cal L}_m$ and $f_2(T)$ are of ``different origin,'' and their inference that only the first contributes to the energy momentum tensor is arbitrary. Also significant, their derivation of equations of motion from a Lagrangian formulation, imposing conservation constraints {\it ad hoc} rather than via Lagrange multipliers, leads to inconsistent conclusions.

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Sarah B. Fisher, Eric D. Carlson. 2020-04-06. Response to Comment on "Reexamining $f(R,T)$ Gravity''. https://doi.org/10.1103/physrevd.101.108502

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