EinsteinRosenBrücke

EinsteinRosenBrücke, commonly referred to as the Einstein–Rosen bridge or wormhole, is a hypothetical feature of spacetime that connects two distant regions via a throat. In general relativity, it is a solution to the Einstein field equations representing a tunnel-like geometry through spacetime.

Origin and geometry: The concept originates from a 1935 paper by Albert Einstein and Nathan Rosen, who interpreted part of the Schwarzschild solution as a bridge between two mirror universes. In the traditional Schwarzschild coordinates, the bridge appears at the Schwarzschild radius; in the maximally extended Kruskal–Szekeres representation, the solution includes two asymptotically flat regions connected by a throat. However, this Einstein-Rosen bridge is non-traversable: the throat collapses too quickly, and any object attempting to cross would encounter a singularity.

Traversability and energy conditions: A stable, traversable wormhole would require exotic matter with negative energy density to keep the throat open, violating standard energy conditions. The 1988 Morris-Thorne framework shows how a traversable wormhole could in principle exist, but such objects remain hypothetical and have not been observed.

Status and implications: Wormholes are a topic of theoretical interest in general relativity, quantum gravity, and cosmology, often used in discussions of causality and speculative time travel. Some modern ideas, such as the ER=EPR conjecture, posit deep connections between wormholes and quantum entanglement, but these remain conjectural.