Weak Deflection Angle and Shadow by Tidal Charged Black Hole
This presentation explores how tidal charge—a signature of extra-dimensional physics—alters the way black holes bend light and cast shadows. Using the Gauss-Bonnet theorem and optical geometry, the authors calculate the weak deflection angle for tidal charged black holes and investigate how plasma further modifies gravitational lensing. The results offer a path to distinguish these exotic objects from standard black holes through observable shadow properties.Script
Black holes don't just swallow light—they twist its path in ways that encode the geometry of spacetime itself. When you add tidal charge, a signature from extra dimensions, the deflection changes in measurable ways that could let us distinguish exotic black holes from ordinary ones.
Tidal charge arises when you take seriously the idea that extra dimensions might exist beyond our familiar four. These charges alter the black hole metric, and the authors set out to measure exactly how much the path of light changes in response.
To tackle this problem, the researchers turned to elegant geometry rather than brute-force calculation.
The Gauss-Bonnet theorem elegantly connects the deflection angle to the curvature of an optical surface wrapped around the black hole. When plasma fills the space, it acts like a refractive medium, tweaking the angle by modifying how photons propagate through the curved geometry.
The results are striking: more tidal charge means less bending. This inverse relationship gives observers a handle to constrain the tidal charge parameter by measuring how sharply light deflects or how large the shadow appears against the cosmic background.
The authors focused on weak gravitational fields, leaving the strong field behavior as open territory. Testing these predictions against real black hole shadows—like those captured for M87 star—will determine whether tidal charge is a real feature of our universe or remains a theoretical curiosity.
If extra dimensions shape the black holes we observe, their shadows will tell the story. Visit EmergentMind.com to explore more research and create your own video presentations.
