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    Finite-time singularities in f(R, T) gravity and the effect of conformal anomaly

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    We investigate f(R,T)f(R,T) gravity models (RR is the curvature scalar and TT is the trace of the stress-energy tensor of ordinary matter) that are able to reproduce the four known types of future finite-time singularities. We choose a suitable expression for the Hubble parameter in order to realise the cosmic acceleration and we introduce two parameters, α\alpha and HsH_s, which characterise each type of singularity. We address conformal anomaly and we observe that it cannot remove the sudden singularity or the type IV one, but, for some values of α\alpha, the big rip and the type III singularity may be avoided. We also find that, even without taking into account conformal anomaly, the big rip and the type III singularity may be removed thanks to the presence of the TT contribution of the f(R,T)f(R,T) theory.Comment: 18 pages; Accepted for publication in Canadian Journal of Physics (CJP
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