Why does a black hole cast a shadow we can see, yet hide its event horizon?
rₛ = 2GM/c² is the point of no return. The bright ring is lensed accretion flow; approaching side brighter by beaming. Dark center is the shadow.
T_H = ℏc³/(8πGM k_B) means black holes radiate.
S_BH = k_B c³ A/(4Gℏ) ties entropy to area.
These predicted the EHT photon ring of M87*. Spacetime geometry makes the invisible measurable.
Which equation changed your view of gravity?