Modified gravity: A unified approach

Starting from the original Einstein action, sometimes called Gamma squared we propose a new setup to formulate modified theories of gravity. This can yield theory with second order field equations similar those found in other popular gravity models. Using more general setting gives fourth equations. model is based on metric alone and does not require geometries. It possible show that our recently proposed $f(Q)$ models are equivalent at level action equations, provided appropriate boundary terms taken into account. Our also match up $f(R)$ which an expected result. Perhaps surprisingly, this equivalence extends $f(T)$ its While these three conceptually different geometrical settings, establish necessary conditions under their indistinguishable. The final part requires matter couple minimally Through work emphasise importance played by heart approach.