Apparent and emergent dark matter around a Schwarzschild black hole

Understand

Inspired by the two different dark matter frameworks that were studied recently: one that arises from the non-local effects of entanglement entropy as emergent gravity (characterized by the parameter $\xi(M)$, and zero-point scale length $l$), and one from dark energy viewed as a superconducting medium (characterized by $\eta(M)$, and screening length parameter $\lambda_{\rm G}$), two black hole solutions spherically surrounded with these dark matter models were derived.

• The effect of these two frameworks on SMBH was analyzed through the resulting deviations in the null regions and the black hole shadow.
• In addition, constraints to the parameters $\xi$ and $\eta$ (at $3\sigma$ level) were found using the available EHT data for Sgr.
• A* and M87*.