Author(s)

Wenxuan Tao

Corresponding Author

Wenxuan Tao

ABSTRACT

In this paper, we investigate a portion of events around a black hole in the view of General Relativity. These events are briefly classified as the “darkness” of black hole and the “danger” around black hole. In other words, we explain why light cannot escape from black holes and why black holes would tear up everything nearby. In the literature review section, we review the history of general relativity, from Maxwell equations to special relativity. In the introduction section, we briefly introduce the basic concept of Riemannian geometry and derive the Einstein equations for gravitation which are the basic of general relativity. The Schwarzschild metric, an explicit solution to Einstein equations under certain assumption, is also discussed. We elaborate in the third and fourth section some cosmological consequences of this solution to answer previous questions. In the third section, we introduce the “darkness” of black hole in various aspects, like exchanging time and radius coordinates, photon sphere and Penrose diagram, etc. In the fourth section, we discuss why black hole is so dangerous to astronauts and celestial bodies in the universes by deriving geodesic deviation equation and tidal force. In the last section, we conclude and summarize our discussions.

KEYWORDS

Black hole, General relativity, Event horizon, Light cone, Penrose diagram, Spaghettification