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Indirect searches of Dark Matter (DM), in conjugation with `missing tracksearches' at the collider seem to confine SU(2)$_L$ fermion triplet DM (FTDM)mass within a narrow range around 1 TeV. The canonical picture of the pure FTDMis in tension since it is under-abundant for the said mass range. Severalpreceding studies have reported that an extra species ($\phi$), redshiftsfaster than the radiation ($\sim a^{-(4+n)}$ where $n>0$), leads to a fasterexpanding early Universe by dominating in the energy density with an enhancedHubble parameter. This has the potential to revive the under-abundant FTDM($\mathbb{Z}_2$ odd, lightest generation) by causing freeze-out earlier withoutmodifying the interaction strength between DM and thermal bath. On the otherhand, although the CP asymmetry produced due to the decay of $\mathbb{Z}_2$even heavier generations of the triplet remains unaffected, its evolution isgreatly affected by the non-standard cosmology. It has been observed throughnumerical estimations that the minimum mass of the triplet, required to producesufficient baryon asymmetry of the Universe (BAU), can be lowered up to twoorders (compared to the standard cosmology) in this fast expansion scenario.The non-standard parameters $n$ and $T_r$ (a reference temperature below whichradiation dominance prevails), which simultaneously control DM abundance aswell as the frozen value of BAU, are tightly constrained from the observedexperimental values. We have found that $n$ is strictly bounded within theinterval $0.4\lesssim n \lesssim 1.8$ where the upper bound is imposed by theBAU constraint whereas the lower bound arises to satisfy the correct DMabundance. It has been noticed that the restriction on $T_r$ is not sostringent as it can vary from sub-GeV to a few tens of GeV.

Reviewing the prospect of fermion triplets as dark matter and source of baryon asymmetry in non-standard cosmology