Remarks on Null Geodesics of Born-Infeld Black Holes

Figure 1

The function 𝑓(𝑟) for various values of 𝑀 for fixed values of 𝑄 and 𝛽. In the top graph (a), 𝑄=1 and 𝛽=1. In the bottom graph (b), 𝑄=0.3 and 𝛽=1.

(a)

(b)