Dark Matter and Energy-Momentum Squared Gravity

In this study, we examine the energy-momentum squared modified theory of gravity, where the squared term $T_{\mu\nu}T^{\mu\nu}$ is incorporated into the conventional gravitational Lagrangian. This modification aims to account for dark matter effects on galactic scales. Specifically, we analyze the model near general relativity solutions for spherically symmetric and static metrics. By fixing the components using the rotational velocities of galaxies, the model demonstrates the emergence of a flat rotation curve in the galactic halo. Additionally, we investigate the proposed model's predictions for the light deflection angle and radar echo delay.