While it is true that, according to our current understanding of physics, it is impossible for an observer outside a black hole to directly observe or interact with anything inside the event horizon, studying what happens inside a black hole's event horizon is still of great interest to physicists. Here are a few reasons why:
Theoretical Understanding: Black holes are fascinating objects that challenge our understanding of the laws of physics, particularly when it comes to extreme conditions like those found inside the event horizon. Studying black holes allows scientists to explore the limits of our current theories, such as general relativity, and potentially uncover new physics.
Event Horizon Dynamics: The behavior of matter and energy as they approach the event horizon is important for understanding the dynamics of black holes. Observing the effects of tidal forces, extreme gravitational redshift, and the distortion of space-time near the event horizon provides valuable insights into the nature of black holes and their interactions with surrounding matter.
Testing Theories: Investigating the properties of black holes can help test alternative theories of gravity and explore the potential connections between general relativity and quantum mechanics. Black holes are thought to be relevant in understanding the interplay between these two fundamental theories.
Astrophysical Significance: Black holes have a significant impact on the evolution of galaxies, the formation of structures in the universe, and the distribution of matter and energy. Understanding black holes' internal dynamics allows us to gain insights into the broader astrophysical processes in which they are involved.
Information Paradox: The study of black holes and their interiors is closely tied to the long-standing problem of the information paradox. It is still an open question how information can escape a black hole or be preserved despite the intense gravitational effects. Research in this area seeks to reconcile the principles of quantum mechanics with the behavior of black holes.
In summary, while direct observations or interactions within a black hole's event horizon may not be possible, studying the physics and dynamics of black holes and their interiors provides valuable insights into the fundamental nature of space, time, and gravity, and helps deepen our understanding of the universe as a whole.